NASASpaceFlight.com Forum
International Space Flight (ESA, Russia, China and others) => Chinese Launchers => Topic started by: Galactic Penguin SST on 04/24/2017 04:56 pm
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Hmm, I can't find a thread for the 2nd flight of the CZ-5 so here it is.
The ships transporting the rocket stages of CZ-5 s/n Y2 (Yuan Wang 21/22) has departed Tianjin port earlier today for Hainan Island (https://twitter.com/cnspaceflight/status/856385750002147328).
SJ-18 will be the 1st Chinese comsat using their big DFH-5 satellite bus - their heaviest ever. With a quoted mass of at least 7 tonnes (one other source says about 8 tonnes and another up to 10 (!)), there's a decent chance that it will break the record for the heaviest geostationary communication satellite.
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LIPS-300 ion engines, too - more powerful versions of the ones on Shijian-13.
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China's CZ-5 (Y2) rocket arrived safely in Hainan, Wenchang
http://www.spaceflightfans.cn/13552.html
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Components of China's 2nd Long March 5 rocket arrived at port at Wenchang today. Will launch heaviest satellite yet, Shijian-18, in June.
https://twitter.com/aj_fi/status/858635271314845696 (https://twitter.com/aj_fi/status/858635271314845696)
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Rumors are currently pointing to a June 30 launch date. ;)
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Rumors are currently pointing to a June 30 launch date. ;)
According to CNSA's Xu Yiansong (speaking at GLEX 2017) (http://sputniknews.cn/china/201706071022803386/), the launch is now scheduled on July 2.
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Looks like they are holding the launch date as the rocket has been rolled out to the launch pad just an hour ago. ;)
Pictures to be posted later.
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"SJ-18" Lonch March 5 begins a transition.
https://twitter.com/cnspaceflight/status/879134302390198274
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LM-5 which will be launched from the WSLC with Shijian-18 next Month completed its transportation to launch site just now.
https://twitter.com/cgwic/status/879341816478392320 (https://twitter.com/cgwic/status/879341816478392320)
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A few more photos of the roll-out from various sources (unfortunately all are low-res):
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Here are some photos and screenshots of the CZ-5 during final assembly and stacking collected by this Chinese forum thread (http://bbs.9ifly.cn/forum.php?mod=viewthread&tid=88828&extra=page%3D1):
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....and what I believe to be the real thing of SJ-18:
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Some nice pictures taken by a Rocket fan
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Some more
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Launch time around 03:20 UTC
A1664/17 - A TEMPORARY RESTRICTED AREA ESTABLISHED WITHIN A CIRCLE CENTERED AT N1937E11057 WITH RADIUS OF 25KM, VERTICAL LIMITS: GND-UNL. GND - UNL, 02 JUL 03:13 2017 UNTIL 02 JUL 08:11 2017. CREATED: 29 JUN 03:03 2017
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Launch time around 03:20 UTC
A1664/17 - A TEMPORARY RESTRICTED AREA ESTABLISHED WITHIN A CIRCLE CENTERED AT N1937E11057 WITH RADIUS OF 25KM, VERTICAL LIMITS: GND-UNL. GND - UNL, 02 JUL 03:13 2017 UNTIL 02 JUL 08:11 2017. CREATED: 29 JUN 03:03 2017
Seems like they get the time zone conversions all wrong. ;)
A1667/17 - A TEMPORARY RESTRICTED AREA ESTABLISHED WITHIN A CIRCLE
CENTERED AT N1937E11057 WITH RADIUS OF 25KM, VERTICAL LIMITS:
GND-UNL. GND - UNL, 02 JUL 11:13 2017 UNTIL 02 JUL 16:11 2017. CREATED: 29 JUN
05:34 2017
11:20 UTC sounds right since previous rumors were for an evening launch. ;)
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Are there any hints about live coverage of the launch?
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Are there any hints about live coverage of the launch?
CCTV's news report during the roll out was fairly extensive so I would expect them to at least provide similar coverage as the last three CZ-5/7 launches, if not even more.
Even if they don't cover it, other media organizations/people visiting Wenchang will be able to do coverage freely, and I am sure plenty of links will appear on launch day.
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NOTAM for CZ-5 resp. boosters and fairing debris
B2279/17 - DUE TO SPACEFLIGHT ACT OF ATM BUREAU OF CAAC, THE FLW RNAV RTE SEGMENTS CLSD:
1. N892 BET KABAM AND MUMOT ALTN RTE: POTIB M646 ABVAR DIRECT MAVRA -FL RESTRICTION : N892 LTD TO FL320, FL360 AND FL400 L625 LTD TO FL310, FL350 AND FL390
2. M501 BET MIKIN AND ALDIS ALTN RTE: NOMAN A461 AVMUP DIRECT LAO AND VISE-VERSA
3. N884 BET DADNU AND LEBIX ALTN RTE: CAB B462 LAO DIRECT LEBIX.
02 JUL 11:22 2017 UNTIL 02 JUL 16:26 2017. CREATED: 30 JUN 03:04 2017
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Fueling of the rocket has already begun at 08:30 UTC today (presumably RP-1 for the boosters): http://www.weibo.com/5386897742/Fao6hfVYo?ref=home&rid=4_0_202_2676189878736606113 (http://www.weibo.com/5386897742/Fao6hfVYo?ref=home&rid=4_0_202_2676189878736606113)
Also it mentions that SJ-18 has some kind of Q-band/V-band communication payload on board for testing.
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https://www.youtube.com/watch?v=-lGRFc6cyXI
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There were quite a few people from the Chinese spaceflight forum that are visiting WSLC for this launch (http://bbs.9ifly.cn/forum.php?mod=viewthread&tid=89359&extra=page%3D1) and they managed to saw the rollout up close:
(I think that mission logo is just someone's own creation and not the official one)
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This thread will be moved to the live section pending the appearance of live coverage links.
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LOX is being loaded
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Seems like SJ-18 will be at just over 7 tonnes: http://news.xinhuanet.com/mil/2017-07/02/c_129645442.htm (http://news.xinhuanet.com/mil/2017-07/02/c_129645442.htm)
SJ-18 also will test a space based laser communication link that (according to SJ-18 chief designer Li Feng) will reach up to 4.8 GB/s downlink speed. It appears that the a quantum communication payload is on board as well (first ever test from geostationary altitude I think?).
(adding news reports screenshots from CCTV which shows the real thing)
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Moved for live coverage.
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There are some rumors indicate T0 is 19:23L
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The service platforms over the boosters are being rotated back to the launch position.
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Have you a link for online video coverage please?
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Have you a link for online video coverage please?
I'm still looking, but the state media explicitly mentioned (http://news.xinhuanet.com/politics/2017-07/01/c_1121247459.htm) that they will do live coverage and they are inviting other media to come so rest assured (?) that they will appear soon. ;)
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Launch time line:
T+0s Liftoff
T+17s Pitch program initiated
T+174s Boosters separation
T+285s Fairing separation
T+465s MECO/1st stage separation/2nd stage ignition
T+753s SECO-1
T+1355s SEI-2
T+1714s SECO-2
T+1810s Spacecraft separation
Source (http://www.newscctv.net/219news/video.html?videoId=CC46619F-6D26-B18F-036B-6114464600AB)
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Upper level opened:
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Have you a link for online video coverage please?
Maybe here:
https://www.youtube.com/watch?v=o2-_-GC9sM4
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CCTV coverage has started here (http://www.newscctv.net/219h5/#/article?videoId=C7CC7C9E-1BEB-D880-2A90-44957E025E7A).
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All service platforms have been swung back.
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Special coverage on CGTN (in english) Start at 11.00 UTC https://m.youtube.com/channel/UCviqjOZN3ZvDEmZfHuUKCIQ
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CCTV coverage has started here (http://www.newscctv.net/219h5/#/article?videoId=C7CC7C9E-1BEB-D880-2A90-44957E025E7A).
There appear to be a lot of buffering problems. Unless it's just my connection, of course.
Does anyone have an idea what the two people in the car are talking about? Are they travelling to the launch?
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CCTV coverage has started here (http://www.newscctv.net/219h5/#/article?videoId=C7CC7C9E-1BEB-D880-2A90-44957E025E7A).
There appear to be a lot of buffering problems. Unless it's just my connection, of course.
Does anyone have an idea what the two people in the car are talking about? Are they travelling to the launch?
Nothing technical. I watched the stream for a few minutes. I believe at one time they were talking about local food such as coconuts and Wenchang chicken. And now they are driving back to the launch complex.
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A nice model...
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The interviewee is one of the Long March 5 lead designers, Mou Yu. A few things he metioned:
1. They improved the engine pre-chill process to address some issues encountered during the maiden launch. And it's working. Today's countdown is very smooth.
2. LH2 loading will stop at T -5 min
3. All ground crews will be evacuated before T-3 hours
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Some cameras in observation point...
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T- minus about one hour....
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Hmm....not sure if they are currently aiming the start of the air/marine space closure window!
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Any idea what happened to the people who were broadcasting as they drove to the launch? Or have I missed them? Do we know who they were?
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Xinhua Video has started webcasting.
We're at T-45 minutes.
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Closeup view.
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Air conditioning duct to the payload fairing has been released:
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What's the URL please Steven?
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T-40 minutes.
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What's the URL please Steven?
It was posted on the previous page, but here it is again.
youtube.com/watch?v=o2-_-GC9sM4
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T-35 minutes. Engineers confident launch will be a success.
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"A little bit windy, here"
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T-30 minutes. Commentator is answering questions from the net.
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T-25 minutes
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According to reports, the target orbit is a 200 x 46000 km super-synchronous transfer orbit.
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Another view.
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What's the URL please Steven?
It was posted on the previous page, but here it is again.
youtube.com/watch?v=o2-_-GC9sM4
This is excellent. Commentator speaking English and taking questions! :)
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CGTN coverage is on.
https://www.youtube.com/watch?v=80Eziy1PGJ0
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They are hoping to still have some light at launch.
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T-20 minutes. Second most powerful launch vehicle in the world (after Delta IV Heavy).
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Special coverage at CGTN
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T-15 minutes.
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CGTN showing rollout video.
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Journalist walked in front of the camera in previous shot.
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Commentator says T0 at 11:30 UTC
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T-10 minutes. This is going by the NOTAM which was for 11:22 UTC. Commentator is saying 11:30 UTC though.
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Talking about recent mishap...
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T-5 minutes.
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T-4 minutes.
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T-3 minutes. Commentator now saying T-5 minutes.
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commentator now says T0 in 5 minutes...
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T-2 minutes.
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T-1 minute.
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1 minute...
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Commentator says it launch launch in 2 to 3 minutes.
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T-40 seconds.
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LIFT OFF !!!!
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Liftoff!
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"Nominal telemetry data" !
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T+1 minute.
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LAUNCH!
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Boosters sep !
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T+2 minutes.
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Booster separation.
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Staging.
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T+5 minutes.
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Payload fairing jettisoned
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T0 was 11:23 UTC
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Rui's article!
https://www.nasaspaceflight.com/2017/07/long-march-5-lofts-shijian-18/
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Fairing separation.
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T+6 minutes.
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T+7 minutes.
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The 2 zones on the schematic are resp for boosters and fairing debris
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T+8 minutes.
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1st stage sep. !
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T+9 minutes.
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Core separation.
T+10 minutes.
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T+11 minutes.
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T+12 minutes.
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Second stage engine cut off !
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Anyone happen to have any timeline for this? The first stage sure burned for a loooooong time. Wikipedia claims 480 secs burn time for the first stage, but I'm fairly sure I saw on screen count (of seconds?) of well over 550 before separation.
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T+13 minutes.
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Engine cutoff.
T+14 minutes.
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This zone is for 1st stage debris
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19:23:23.425 Beijing Time.
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Burn complete.
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T+15 minutes.
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T+16 minutes.
About two minutes to separation.
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T+17 minutes.
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New China has gone off line. Had a brief live view of the satellite then the feed stopped.
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Another nice model ...
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We're still waiting on confirmation of satellite separation.
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S/C sep due in 7 minutes
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Anyone happen to have any timeline for this? The first stage sure burned for a loooooong time. Wikipedia claims 480 secs burn time for the first stage, but I'm fairly sure I saw on screen count (of seconds?) of well over 550 before separation.
Spaceflight 101 says first stage sep was at T+570 s (planned time was T+465 s) and shutdown at T+788 s (planned time was T+753s). Is there a problem?
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Anyone happen to have any timeline for this? The first stage sure burned for a loooooong time. Wikipedia claims 480 secs burn time for the first stage, but I'm fairly sure I saw on screen count (of seconds?) of well over 550 before separation.
Spaceflight 101 says first stage sep was at T+570 s (planned time was T+465 s) and shutdown at T+788 s (planned time was T+753s). Is there a problem?
I meant to say second stage shutdown was at T+788s vs. T+753s as planned.
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Mission isn't over yet.
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S/C sep due in 7 minutes
I misread the launch schedule, thinking it was in minutes and seconds. Separation is at T+30 minutes 10 seconds with launch at 11:23:23.425 UTC. That means separations is at 11:53:33 UTC.
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Separation in about one minute.
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Separation should be occurring now. Still talking about international cooperation.
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Long March-5 Y2 launches Shijian-18
https://www.youtube.com/watch?v=XvuZMQZF8yA
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End of nice (as usual) CGTN "Destination Space" coverage !
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CGTN is wrapping up coverage. Still waiting on confirmation of satellite separation.
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The CGTN news is saying its a successful launch.
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The CGTN news is saying its a successful launch.
Then she corrected it to just "launched", guess something happened.
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It seems that the second stage is malfunctioned.
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No official Announced a successful launch, so......
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It seems that the second stage is malfunctioned.
Source?
bit odd however that there is no official announce yet of a success..
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Great work Steven, centaurinasa and others!
Rui's article:
https://www.nasaspaceflight.com/2017/07/long-march-5-lofts-shijian-18/
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Failed
新华社:长征五号遥二火箭飞行出现异常,发射任务失利。
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Failed
新华社:长征五号遥二火箭飞行出现异常,发射任务失利。
Bing Translation.
"Xinhua News Agency: No. Fifth, two rockets flying in the Long March, the launch mission failed."
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Failed
新华社:长征五号遥二火箭飞行出现异常,发射任务失利。
No info if there as a second stage failure or a satellite separation failure?
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Failed
新华社:长征五号遥二火箭飞行出现异常,发射任务失利。
Bing Translation.
"Xinhua News Agency: No. Fifth, two rockets flying in the Long March, the launch mission failed."
Rather "CZ-5 Y2, lauch mission failure"
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Failed
新华社:长征五号遥二火箭飞行出现异常,发射任务失利。
No info if there as a second stage failure or a satellite separation failure?
No info
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Yep, confirmation launch is a failure, second stage (likely).
It's too early to speculate but would this failure have an impact on the Chang'e 5 launch date to 2018?
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Failed
新华社:长征五号遥二火箭飞行出现异常,发射任务失利。
Google translation: (slightly different than Bing apparently)
Xinhua News Agency: Long March five remote rocket flight anomalies, launch mission failure.
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Failed
新华社:长征五号遥二火箭飞行出现异常,发射任务失利。
No info if there as a second stage failure or a satellite separation failure?
No info
CGTN's guest said second stage failure.
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CGTN reports that the issue appeared at around 20min into the flight
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The last images transmitted live, seems to show that the 2nd stage ignit for only a few seconds before shutting down...
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Not sure but, the last images transmitted live, seems to show that the 2nd stage ignit for a few seconds before shutting down...
Well it was purposed to make a second burn at this mission true?
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Yes, that's commentator say
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Official announcement of failure:
http://news.xinhuanet.com/politics/2017-07/02/c_1121250175.htm (http://news.xinhuanet.com/politics/2017-07/02/c_1121250175.htm)
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Second ignition was to occur at T+1355 seconds (T+22:45 minutes). My last screen shot of the control room was at T+1020 (T+17 minutes). Going back to the YouTube recording, the last shot was at T+1091 seconds (T+18:11 minutes), 264 seconds (4:24 minutes) before second ignition.
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Actually I think the core stage is probably where all the things started. The velocity curve seems to be dropping quickly by the time the 2nd stage was flying free. SEI-1 was almost 2 minutes late and then there was some strange outgassing from the 1st stage that started from T+5 minutes or so. :-X
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I removed my premature congratulations from a couple pages ago :( Although the early flight performance was impressive - still some bugs to iron out, apparently! Better luck next time, China. You'll get there with your potentially excellent rocket, soon, I know it.
Thanks for the good coverage, guys.
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Seems that the curve did not follow the flight profile...
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Well, let's say that at least the gremlins hit on the launch with the smallest stake. At least it isn't Chang'e 5, any of their space station modules or their Mars probe that is down the drink right now.
If it hit on the very 1st launch it might have been somewhat devastating too...
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Burn complete.
(http://forum.nasaspaceflight.com/index.php?action=dlattach;topic=42798.0;attach=1436794;image)
The top-left graph in this screenshot seems wrong to me. Could anyone make sense of it?
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Ouch :( That hurts, China. 2017 is going to be one of the most boring years in space now, as there won't be an interplanetary launch (Long March 5 had to launch Chang'e 5)...
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T+11 minutes.
Seems like the right side engine failed?
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Burn complete.
(http://forum.nasaspaceflight.com/index.php?action=dlattach;topic=42798.0;attach=1436794;image)
The top-left graph in this screenshot seems wrong to me. Could anyone make sense of it?
I believe the yellow line is the current trajectory and the line just above that is the planned trajectory. As you can see, it's way off.
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Actually I think the core stage is probably where all the things started. The velocity curve seems to be dropping quickly by the time the 2nd stage was flying free. SEI-1 was almost 2 minutes late and then there was some strange outgassing from the 1st stage that started from T+5 minutes or so. :-X
I see what you noted. Where normally you seeing the exhaust of the rocket engine there is suddenly a notable plume out of nothing. So far I know there was no MECO at that time so it's something odd, at least.
Hold on I try to capture it. (Edit: got it)
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Ouch :( That hurts, China. 2017 is going to be one of the most boring years in space now, as there won't be an interplanetary launch (Long March 5 had to launch Chang'e 5)...
This is part of the "rocket science"...
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This is part of the "rocket science"...
That's right :( On that count, 2017 is really *that* disappointing. What a horrible year. China's heavy lift carrier suffered a failure (which will probably delay Chang'e 5 to next year). There won't be a manned flight to space as SpaceX had their own delays, Blue Origin is not showing anything significant this year concerning New Shepard, Google Lunar XPrize suffered more delays (SpaceIL is delayed to 2018 at earliest and Team Indus has its own problems), and despite Richard Branson's optimism, we'll see if SpaceShip Two will start at least powered flights...
Let's hope that the small launcher industry will start more fluently, at least..
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and then there was some strange outgassing from the 1st stage that started from T+5 minutes or so. :-X
Agreed, I literally said "Hmm, that doesn't look good" aloud when that started up.
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The vertical lines on the graph in that screenshot are at 250-second intervals, so it looks like the deviation began somewhere around the 400-second mark. That would put it before staging.
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and then there was some strange outgassing from the 1st stage that started from T+5 minutes or so. :-X
Agreed, I literally said "Hmm, that doesn't look good" aloud when that started up.
Indeed, also as so far I can look back, the second stage did look normally. Does the LM-5 having an automatically shutdown system if something goes wrong and cannot being compromised anymore?
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Actually I think the core stage is probably where all the things started. The velocity curve seems to be dropping quickly by the time the 2nd stage was flying free. SEI-1 was almost 2 minutes late and then there was some strange outgassing from the 1st stage that started from T+5 minutes or so. :-X
Is the curve that starts to drop velocity or altitude?
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This is part of the "rocket science"...
That's right :( On that count, 2017 is really *that* disappointing. What a horrible year. China's heavy lift carrier suffered a failure (which will probably delay Chang'e 5 to next year). There won't be a manned flight to space as SpaceX had their own delays, Blue Origin is not showing anything significant this year concerning New Shepard, Google Lunar XPrize suffered more delays (SpaceIL is delayed to 2018 at earliest and Team Indus has its own problems), and despite Richard Branson's optimism, we'll see if SpaceShip Two will start at least powered flights...
Let's hope that the small launcher industry will start more fluently, at least..
There *will* be manned flights because the Russians are still launching crews on the Soyuz-MS spacecraft.
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Does anyone have a cleaner feed of the launch (not the New China TV one which used their camera to film the LCC screen instead) through to 2nd stage flying?
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...Is the curve that starts to drop velocity or altitude?
I think it's the altitude...
https://twitter.com/search?src=typd&q=china%20spaceflight
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China says launch of Long March-5 Y2 "unsuccessful" (http://news.xinhuanet.com/english/2017-07/02/c_136411480.htm).
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T+11 minutes.
Stage 2 flame suddenly become asymmetrical here.
Both stage 1 and stage 2 have different fatal problem?
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...Is the curve that starts to drop velocity or altitude?
I think it's the altitude...
https://twitter.com/search?src=typd&q=china%20spaceflight
The correct altitude during stage 2 burning and coasting = GTO perigee = 185~200km
So the stage 2 started reentry over 100km at the moment ?
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It is very likely that Chang'e 4 will be launched before Chang'e 5...
This is part of the "rocket science"...
That's right :( On that count, 2017 is really *that* disappointing. What a horrible year. China's heavy lift carrier suffered a failure (which will probably delay Chang'e 5 to next year). There won't be a manned flight to space as SpaceX had their own delays, Blue Origin is not showing anything significant this year concerning New Shepard, Google Lunar XPrize suffered more delays (SpaceIL is delayed to 2018 at earliest and Team Indus has its own problems), and despite Richard Branson's optimism, we'll see if SpaceShip Two will start at least powered flights...
Let's hope that the small launcher industry will start more fluently, at least..
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https://twitter.com/search?src=typd&q=china%20spaceflight
Seems that's a confirmation on 1st stage malfunction.....
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I suspected that was just turbopump exhaust but after watching again it appears that maybe it does develop into the big plume. Either way, that feature was present before the big outgassing previously mentioned, which starts pretty bad but gets much worse over time. By the time the footage cuts back to the reporters(on the feed I was watching) it almost looks like it's getting into the ballpark of CRS-7 style bad.
The reporters on the feed I was watching didn't really seem to know what they were talking about most of the time, but at one point they mentioned that the ascent camera is on the second stage, just for info.
Edit to add a shot showing the feature is clearly visible at booster separation. Before that I can almost convince myself that I can see where it starts up(a lens flare conveniently moves to highlight it at the time I'm talking about), but it's too obscured to make a conclusion.
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I suspected that was just turbopump exhaust but after watching again it appears that maybe it does develop into the big plume. Either way, that feature was present before the big outgassing previously mentioned, which starts pretty bad but gets much worse over time. By the time the footage cuts back to the reporters(on the feed I was watching) it almost looks like it's getting into the ballpark of CRS-7 style bad.
The reporters on the feed I was watching didn't really seem to know what they were talking about most of the time, but at one point they mentioned that the ascent camera is on the second stage, just for info.
TP exhaust turned into cold plume, TP failure?
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"The second launch of China's heavy-lift carrier rocket, the Long March-5, on Sunday was unsuccessful.
The rocket started to malfunction shortly after take-off, but the abnormality that led to the mission's failure was not immediately clear."
https://twitter.com/search?src=typd&q=china%20spaceflight
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https://www.youtube.com/watch?v=NahRe9rqo1I
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There is rumor that one of YF77s lost its chamber pressure around 350 seconds after launch
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I did a little analysis on the velocity curve from the now-infamous graph from that screenshot. Looks like the velocity curve starts to fall short around 360 seconds into flight, about 2 minutes before scheduled stage 1 cutoff and about 3.5 minutes before actual cutoff.
Edit - this seems basically consistent with the rumor SmallKing posted. If 1 of 2 YF77s failed, the remaining fuel should logically take about twice as long to consume, turning ~2 minutes burn remaining into ~4.
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There is rumor that one of YF77s lost its chamber pressure around 350 seconds after launch
I found a replay of the launch on a Chinese site - it looks like that the timing would fit perfectly with the outgassing event on the rocket's left side, which started at T+348 seconds (T+5:48).
Venting of the cold turbopump exhaust after the turbopump stopped would explain the venting as seen on the rocket cam.
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That is too bad the Long March 5 failed. The folks in China have a on the road space program! Second launches can be hard. Check out the second Saturn 5 launch, it worked but with problems.
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This is part of the "rocket science"...
That's right :( On that count, 2017 is really *that* disappointing. What a horrible year. China's heavy lift carrier suffered a failure (which will probably delay Chang'e 5 to next year). There won't be a manned flight to space as SpaceX had their own delays, Blue Origin is not showing anything significant this year concerning New Shepard, Google Lunar XPrize suffered more delays (SpaceIL is delayed to 2018 at earliest and Team Indus has its own problems), and despite Richard Branson's optimism, we'll see if SpaceShip Two will start at least powered flights...
Let's hope that the small launcher industry will start more fluently, at least..
... yes. I have high hopes for Electron's second flight - some new ideas there.
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Somebody in Wikipedia: "a minor problem occurred during flight and the rocket put the YZ-2 upper stage and satellite into an orbit that was less accurate than expected. However, the trajectory was easily corrected with the YZ-2 upper stage and the payload was inserted into the desired orbit." It cites a site in Chinese.
https://en.wikipedia.org/wiki/Long_March_5
In the introductory text I had changed "succesful" -> "not succesfull", based on the current NSF forum, before I read that description. So, I don't know, what to belive... The Wikipedia article is inconsistent now, because of me...
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Somebody in Wikipedia: "a minor problem occurred during flight and the rocket put the YZ-2 upper stage and satellite into an orbit that was less accurate than expected. However, the trajectory was easily corrected with the YZ-2 upper stage and the payload was inserted into the desired orbit." It cites a site in Chinese.
https://en.wikipedia.org/wiki/Long_March_5
In the introductory text I had changed "succesful" -> "not succesfull", based on the current NSF forum, before I read that description. So, I don't know, what to belive... The Wikipedia article is inconsistent now, because of me...
I believe this refers to the maiden flight last November.
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My mistake. Somebody has corrected it back.
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Big question is where the debris -- large stages with lots of propellant -- fell back to Earth. There might be spectacular videos from sea and air traffic in the impact zone.
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Big question is where the debris -- large stages with lots of propellant -- fell back to Earth. There might be spectacular videos from sea and air traffic in the impact zone.
This didn't fail right off the launch pad. It sounds like an engine failed after fairing separation, so out of the atmosphere. The rocket used most or all of its propellant and anything left should break up when it reenters the atmosphere.
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According to reports, the target orbit is a 200 x 46000 km super-synchronous transfer orbit.
A postmortem remark - apparently according to an interview with one of the program managers before launch on CCTV the target orbit was 200 x 46000 km x 19.5 deg. with the satellite at 7.6 tonnes.
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Does anyone have a cleaner feed of the launch (not the New China TV one which used their camera to film the LCC screen instead) through to 2nd stage flying?
https://www.youtube.com/watch?v=LyKXiXTRAuI
Liftoff at 5:05
Booster separation at 7:59 (T+2:54) (normal)
Starting from 9:19 (T+4:14) the exhaust plume on the right side suddenly got much brighter
<speculation>I wonder if its just the sunset exhaust plume light show (liftoff was about 4 minutes after local sunset) or if it indicates a leak on a propellant feed line? </speculation>
Fairing separation is at 9:48 (T+4:43) (normal)
What is sure is that all went wrong at 10:49 (T+5:44) when the left engine plume catastrophically turned into gas venting - that fits in with the rumored time that the 1st stage engine #1's turbopump went down.
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What is sure is that all went wrong at 10:49 (T+5:44) when the left engine plume catastrophically turned into gas venting - that fits in with the rumored time that the 1st stage engine #1's turbopump went down.
You can see the accompanying attitude disturbance it caused by watching the Earth's horizon.
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I stopped watching just before the failure thinking that at that point nothing could go wrong. >:(
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Wouldn't there be an engine management function that would shut down the engine experiencing the problem but have the good engine continue burning longer to make up the shortfall ??...why wasn't the mission saved with a longer S1 one engine burn and a successful S2 burn ??
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Big question is where the debris -- large stages with lots of propellant -- fell back to Earth. There might be spectacular videos from sea and air traffic in the impact zone.
This didn't fail right off the launch pad. It sounds like an engine failed after fairing separation, so out of the atmosphere. The rocket used most or all of its propellant and anything left should break up when it reenters the atmosphere.
Roger that. A possible approximate visual analogy could be the 2011 Meridian launch failure in mid-3rd-stage, illuminated by the western sun, actual explosion caught by dashcam in Chelyabinsk, expanding cloud observed downrange as it fell into Earth shadow, then fireballs at final reentry [and debris picked up on streets]. Here's my report: Meridian-5 launch failure and subsequent downrange observations. This time, north and northeast of the Philippines, there ought to have been lots of witnesses, some with cameras.
http://satobs.org/seesat_ref/misc/meridian_crash_2011_draft.pdf
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Possible in principle, but it has to be designed that way. The longer burn needs enough stuff to burn to make it happen. If it's not needed it becomes a burden.
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No serendipitous viewing opportunity from ISS, it was heading SW to NE across North America during the launch phase.
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Wouldn't there be an engine management function that would shut down the engine experiencing the problem but have the good engine continue burning longer to make up the shortfall ??...why wasn't the mission saved with a longer S1 one engine burn and a successful S2 burn ??
Further to Phil's point, most expendable LVs run entirely on their on-board logic and have no facility to respond to ground commands. If the IU wasn't programmed to compensate for this contingency, then no mitigating action was possible.
One hardware-based possibility is that the turbopump failure also took out the upstream valves between the prop tanks and the engines so there was no way to stop the vent-to-vacuum of the prop through the remains of the engine. So, the IU was not only trying to compensate for huge cosine losses with the remaining engine but was also trying to compensate from off-axis thrust from the venting that also meant propellent was being wasted at quite a high rate. It looks like the combination left the vehicle both low and slow at stage separation.
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With a 2 engine system, if one engine stops burning, the second engine may not be able to gimbal sufficiently to fire through the stack center of mass. Also, there may not be enough thrust to accelerate. These things are not Boeing 777s, there is not a lot of redundancy in the engines.
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Since stage separation reportedly did occur, the stack should have flown very far downrange. Did the third stage fire?
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Starting to get videos POSSIBLY of the rocket from the Philippines: https://www.youtube.com/watch?v=tYJN6GplSv0
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With a 2 engine system, if one engine stops burning, the second engine may not be able to gimbal sufficiently to fire through the stack center of mass. Also, there may not be enough thrust to accelerate. These things are not Boeing 777s, there is not a lot of redundancy in the engines.
So just out of curiosity, if the Atlas V loses an engine, that's LOM .??...didn't SpaceX lose an engine early on with an F9 but the remaining engines saved the mission...I would have thought that an experienced country like China would develop their launch vehicles with engine out survivability?
Edit: spelling
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Atlas-V has only one core engine (a single set of plumbing feeding two separate chambers) so a turbopump failure would be an instant LOM/LOV yes.
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With a 2 engine system, if one engine stops burning, the second engine may not be able to gimbal sufficiently to fire through the stack center of mass. Also, there may not be enough thrust to accelerate. These things are not Boeing 777s, there is not a lot of redundancy in the engines.
So just out of curiosity, if the Atlas V loses an engine, that's LOM .??...didn't SpaceX lose an engine early on with an F9 but the remaining engines saved the mission...I would have thought that an experienced country like China would develop their launch vehicles with engine out survivability?
Edit: spelling
Atlas V has only one engine, so yes, losing an engine would be LOM. Engine out survivability is dependent on architecture. Also, engine out survibability through multiple small engines together is not necessarily the best choice for rockets, even though it might save you sometimes; thebenefits might not outweigh he cost. Also, think about upper stages - most have only 1 engine, so engine out there is not really possible. Your 'experienced country' does not translate at all to having more engines on stages; look at any number of rockets from ESA, NASA in the past, JAXA, ULA.
My condolances to the Chinese- sad such a huge and interesting satellite and mission was lost.
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With a 2 engine system, if one engine stops burning, the second engine may not be able to gimbal sufficiently to fire through the stack center of mass. Also, there may not be enough thrust to accelerate. These things are not Boeing 777s, there is not a lot of redundancy in the engines.
So just out of curiosity, if the Atlas V loses an engine, that's LOM .??...didn't SpaceX lose an engine early on with an F9 but the remaining engines saved the mission...I would have thought that an experienced country like China would develop their launch vehicles with engine out survivability?
Edit: spelling
Atlas V has only one engine, so yes, losing an engine would be LOM. Engine out survivability is dependent on architecture. Also, engine out survibability through multiple small engines together is not necessarily the best choice for rockets, even though it might save you sometimes; thebenefits might not outweigh he cost. Also, think about upper stages - most have only 1 engine, so engine out there is not really possible. Your 'experienced country' does not translate at all to having more engines on stages; look at any number of rockets from ESA, NASA in the past, JAXA, ULA.
My condolances to the Chinese- sad such a huge and interesting satellite and mission was lost.
F9 did lose an engine on an early flight, but since it has nine first stage engines, the loss only reduced thrust by 1/9 = 11% (more or less). The other eight could more easily make up the shortfall than if a two-engine first stage lost one engine (50% of thrust), or clearly if a solitary engine failed.
That seems to make multiple engines a clearly superior architecture, then again multiple engines means multiple chances at engine failure. A single engine that is 99% reliable but not allowed to fail may (or may not) be more reliable overall than nine engines that are each 99% reliable (or 98%, or 99.3%), but with an allowance for one "free" failure. The optimal design will vary widely for each rocket being designed.
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I'm going to take a step back and note that we can do a post-mortem because we got a live video feed from the Chinese space program. Kudos to them for the openness, it wasn't always this way.
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I'm going to take a step back and note that we can do a post-mortem because we got a live video feed from the Chinese space program. Kudos to them for the openness, it wasn't always this way.
Its kind of different because WSLC is not a military installation and the launcher families that launch from WSLC are not derived from missiles thus everything has been broadcast so far whereas launchers from the CZ-2 and CZ-4 families are orbital versions of active, albeit soon to be retired missiles (ICBM) in China's arsenal. Suborbital launches of the missile configurations DF-5/5A/5B have slowed down in recent years while DF-5C is the latest and likely last DF-5 ICBM version as it is due to be replaced by the solid fueled DF-41 which has greater capabilities than DF-5.
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Sorry to hear about China launch failure today. I know how painful that is to the people who designed & built it.
https://twitter.com/elonmusk/status/881572917586178048 (https://twitter.com/elonmusk/status/881572917586178048)
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This is unfortunate...
https://www.youtube.com/watch?v=LyKXiXTRAuI
This is probably not related to the failure (it seems), but if you look at this video there seems to be some material dangling loose at the base of at least two boosters. It is most clearly seen around 7:07 of the video. Is that normal? And if not, is it metal pieces or some sort of insulation fabric? And could it have swung and and damaged one of the core engines?
(attached image below, but watch the video, it is more obvious there)
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Since stage separation reportedly did occur, the stack should have flown very far downrange. Did the third stage fire?
There is no way the 3rd stage would fire this early in the mission. Stage 2 was meant to enter parking orbit and then
reignite to GTO; stage 3 increases GTO apogee after that, with its first burn at T+31 minutes.
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Since stage separation reportedly did occur, the stack should have flown very far downrange. Did the third stage fire?
There is no way the 3rd stage would fire this early in the mission. Stage 2 was meant to enter parking orbit and then
reignite to GTO; stage 3 increases GTO apogee after that, with its first burn at T+31 minutes.
Have I missed something? I thought that it was two core stages plus four strap-ons - no third stage, unless you call the strap-ons alone stage 1.
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Since stage separation reportedly did occur, the stack should have flown very far downrange. Did the third stage fire?
There is no way the 3rd stage would fire this early in the mission. Stage 2 was meant to enter parking orbit and then
reignite to GTO; stage 3 increases GTO apogee after that, with its first burn at T+31 minutes.
Have I missed something? I thought that it was two core stages plus four strap-ons - no third stage, unless you call the strap-ons alone stage 1.
Long March 5 has an optional third stage called YZ-2, using hypergolic propellants. This had already been used in the first launch (and came in quite handy, as it could compensate for a performance shortfall of the second stage) https://en.wikipedia.org/wiki/Long_March_5
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Since stage separation reportedly did occur, the stack should have flown very far downrange. Did the third stage fire?
There is no way the 3rd stage would fire this early in the mission. Stage 2 was meant to enter parking orbit and then
reignite to GTO; stage 3 increases GTO apogee after that, with its first burn at T+31 minutes.
Have I missed something? I thought that it was two core stages plus four strap-ons - no third stage, unless you call the strap-ons alone stage 1.
Long March 5 has an optional third stage called YZ-2, using hypergolic propellants. This had already been used in the first launch (and came in quite handy, as it could compensate for a performance shortfall of the second stage) https://en.wikipedia.org/wiki/Long_March_5
This launch didn't use it though: http://space.skyrocket.de/doc_lau_det/cz-5.htm (version 1st flight, in Gunter's nomenclature)
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Since stage separation reportedly did occur, the stack should have flown very far downrange. Did the third stage fire?
There is no way the 3rd stage would fire this early in the mission. Stage 2 was meant to enter parking orbit and then
reignite to GTO; stage 3 increases GTO apogee after that, with its first burn at T+31 minutes.
Have I missed something? I thought that it was two core stages plus four strap-ons - no third stage, unless you call the strap-ons alone stage 1.
Long March 5 has an optional third stage called YZ-2, using hypergolic propellants. This had already been used in the first launch (and came in quite handy, as it could compensate for a performance shortfall of the second stage) https://en.wikipedia.org/wiki/Long_March_5
4 stages total for current versions of CZ-5 family:
2 Stage: CZ-5B
3 Stage: CZ-5
4 Stage: CZ-5/YZ-2
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This is probably not related to the failure (it seems), but if you look at this video there seems to be some material dangling loose at the base of at least two boosters. It is most clearly seen around 7:07 of the video. Is that normal? And if not, is it metal pieces or some sort of insulation fabric? And could it have swung and and damaged one of the core engines?
I noticed that. It does not look normal to me. It might be a structural issue, perhaps a cause or an effect of the failure.
- Ed Kyle
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With a 2 engine system, if one engine stops burning, the second engine may not be able to gimbal sufficiently to fire through the stack center of mass. Also, there may not be enough thrust to accelerate. These things are not Boeing 777s, there is not a lot of redundancy in the engines.
So just out of curiosity, if the Atlas V loses an engine, that's LOM .??...didn't SpaceX lose an engine early on with an F9 but the remaining engines saved the mission...I would have thought that an experienced country like China would develop their launch vehicles with engine out survivability?
Edit: spelling
There is a single RD-180 that boosts Atlas V, so if it goes down, that is indeed LOM.
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This is probably not related to the failure (it seems), but if you look at this video there seems to be some material dangling loose at the base of at least two boosters. It is most clearly seen around 7:07 of the video. Is that normal? And if not, is it metal pieces or some sort of insulation fabric? And could it have swung and and damaged one of the core engines?
I noticed that. It does not look normal to me. It might be a structural issue, perhaps a cause or an effect of the failure.
- Ed Kyle
Looking at the booster separation, and footage from the liftoff, this may actually just be insulation covers wrapped around the booster attachment rods that came loose. Or it could be something more.
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You can see something flapping briefly on the booster to the right at the same level. Probably just insulation.
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So what happened to the satellite? Did it reach parking orbit?
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I've also watched the video feed from a camera watching the mission control centre screens which show some different views not shown on other feeds. Here's the You Tube link https://youtu.be/o2-_-GC9sM4
Note the three photos taken from this video. The first shows a nice clean shot down from the second stage to the core at 57:52. The second photo at 58:23 shows the camera getting fogged up by a stream of something coming from the second stage above the camera. The third photo taken at 59:35 shows a heavy stream affecting the camera. If you watch the video you'll see the stream start in another camera angle, it's on a half domed structure that's to the right bottom of that camera angle. Then as you see the stream start as in the pictures it increases slowly and maybe becomes liquid. My guess is it's fuel leaking from the second stage? Check it out and let me know your thoughts.
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So what happened to the satellite? Did it reach parking orbit?
No, It doesn't seem like it. This is basically a situation similar to the Atlas V / Cygnus launch last year, but this time the performance shortfall from the first stage was much more severe, and the 2nd stage could not make up the difference.
My guess is it's fuel leaking from the second stage? Check it out and let me know your thoughts.
No the evidence that exists (much longer first stage burn than expected and video) suggests that the problem was in the first stage, and more specifically one of the two engines.
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Watch the video at 1:03:32 on. The lower stage separates then you see engine(s) fire up and gimballing then within seconds stop firing but you can still see gimballing going on. I'm not saying there wasn't a problem with the first stage I'm saying both stages had problems.
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Watch the video at 1:03:32 on. The lower stage separates then you see engine(s) fire up and gimballing then within seconds stop firing but you can still see gimballing going on. I'm not saying there wasn't a problem with the first stage I'm saying both stages had problems.
The upper stage might have issues as well, but the first stage must contain the root cause. The upper stage does seem to shut down quickly after the first start, but that might be caused by propellant settling issues due to atmospheric friction. Later the engines do seem to start(?) - but that glow is most likely from the re-entry. (The light looks very different than the short engine start at 1:03:38)
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Since stage separation reportedly did occur, the stack should have flown very far downrange. Did the third stage fire?
There is no way the 3rd stage would fire this early in the mission. Stage 2 was meant to enter parking orbit and then
reignite to GTO; stage 3 increases GTO apogee after that, with its first burn at T+31 minutes.
Have I missed something? I thought that it was two core stages plus four strap-ons - no third stage, unless you call the strap-ons alone stage 1.
Long March 5 has an optional third stage called YZ-2, using hypergolic propellants. This had already been used in the first launch (and came in quite handy, as it could compensate for a performance shortfall of the second stage) https://en.wikipedia.org/wiki/Long_March_5
What you say is correct, but on this launch, Y-2, the YZ-2 was not carried therefore it was a two-stage launch vehicle, as I said ..........
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Wouldn't there be an engine management function that would shut down the engine experiencing the problem but have the good engine continue burning longer to make up the shortfall ??...why wasn't the mission saved with a longer S1 one engine burn and a successful S2 burn ??
GNC engine management does happened already, separation delayed 100 seconds and S2 operation continued.
But T/W with S1 only one engine and T/W of S2 is not enough to save the mission.
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This is unfortunate...
This is probably not related to the failure (it seems), but if you look at this video there seems to be some material dangling loose at the base of at least two boosters. It is most clearly seen around 7:07 of the video. Is that normal? And if not, is it metal pieces or some sort of insulation fabric? And could it have swung and and damaged one of the core engines?
(attached image below, but watch the video, it is more obvious there)
The flappy bit is quite normal, or at least there is an identical occurrence on the successful launch of november last year.
See: https://www.youtube.com/watch?v=T1Ysyoud9q0#t=101
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I know that this is academic, but do we know where Shijian 18 was planned to be located?
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It is easy to forget that, despite it size, increasingly cosmopolitan people and economic power, China is not a free society and, in times of great official embarrassment, will not even pretend to be.
It is obvious that this launch failure has metamorphosed into a serious political embarrassment for someone with power and we can officially expect to not hear anything else from official Chinese sources. It will be harder for the Chinese to pretend that the launch never happened as it once was. I suspect that the most we will hear after this is rumblings from anonymous CSA sources of 'foreign-funded saboteurs'.
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Unfortunate the "old guard" still rears its head uglily in a futile exercise of showing how these situations should not be handled, both for integrity and, frankly, because it serves no purpose in today's interconnected societies, especially China's -and is actually detrimental to their assumed objective, only fueling rumors and baseless speculation in underground circles.
Hopefully they will be increasingly substituted with more open-minded personalities. Also hopefully, some recent hermetist Western attitudes won't give them a new justification to their attitude.
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It is easy to forget that, despite it size, increasingly cosmopolitan people and economic power, China is not a free society and, in times of great official embarrassment, will not even pretend to be.
It is obvious that this launch failure has metamorphosed into a serious political embarrassment for someone with power and we can officially expect to not hear anything else from official Chinese sources. It will be harder for the Chinese to pretend that the launch never happened as it once was. I suspect that the most we will hear after this is rumblings from anonymous CSA sources of 'foreign-funded saboteurs'.
Yes, I agree that it was quite the embarrassment - especially that the launch was streamed live and people saw what went wrong in real time.
I am afraid that Chinese bureaucrats will now make the missions even less public and live streams will become even rarer.
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I had been thinking about that strange leak on the right side - could this be the very first case of us seeing the effect of not fully combusted exhaust leaking through the nozzle into outer space (be it a case of leaky valves, burnt through pipelines or such) on rocket cam? With the launch right on the terminator, the lighting effects would enhance any particle streams around the rocket.
This might suggest a gradual leak somewhere instead of a turbopump RUD (chamber burnt through etc.) or pressurization problem I think?
What is strange is that the flow is heading towards the front - I can't think of why (exosphere atmospheric effect?).
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It is easy to forget that, despite it size, increasingly cosmopolitan people and economic power, China is not a free society and, in times of great official embarrassment, will not even pretend to be.
It is obvious that this launch failure has metamorphosed into a serious political embarrassment for someone with power and we can officially expect to not hear anything else from official Chinese sources. It will be harder for the Chinese to pretend that the launch never happened as it once was. I suspect that the most we will hear after this is rumblings from anonymous CSA sources of 'foreign-funded saboteurs'.
Yes, I agree that it was quite the embarrassment - especially that the launch was streamed live and people saw what went wrong in real time.
I am afraid that Chinese bureaucrats will now make the missions even less public and live streams will become even rarer.
I was impressed that this launch was broadcast live, failure or not. If anything, this failure showed the robustness of the design, as the wounded rocket kept fighting to ascend. I hope China's decision makers see it that way and show the world the next attempt live.
- Ed Kyle
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For the record, here is a navigational warning concerning nominal drop zones (boosters, fairing, 1st stage)
(source (http://www.eastpendulum.com/longue-marche-5-echec-du-2eme-vol))
NAVAREA航行警報 NO.17-0427
南シナ海北部及び北太平洋西部、ロケット打ち上げに伴う危険区域設定
NO.17-0427 発表日時:2017年06月30日 20時
SOUTH CHINA SEA, NORTHERN PART AND NORTH
PACIFIC, WESTERN PART.
ROCKET LAUNCHING. 021000Z TO 021300Z
JUL. FOLLOWING RANGE CLEARANCE AREAS
ESTABLISHED. AREAS BOUNDED BY
A. 19-07.2N 119-06.1E
19-10.5N 118-03.3E
19-37.4N 118-04.8E
19-34.1N 119-07.7E.
B. 18-45.3N 124-00.2E
18-52.2N 122-35.0E
19-19.0N 122-37.3E
19-12.2N 124-02.7E.
C. 15-22.9N 144-36.9E
15-48.7N 142-25.2E
16-41.6N 142-36.1E
16-15.7N 144-48.4E.
CANCEL THIS MSG 021400Z JUL.
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Do we have a good idea where any debris would have landed?
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Also any information about the 2nd burn of the 2nd stage?
The velocity did not deviate the projection much, but the altitude was way off. If that altitude curve was accurate, the 2nd stage was dipping towards 100 km. It could be reentering before the 2nd burn. That was quite unexpected. One of the core engine lost thrust fairly late into the 1st stage burn, and the remaining engine burned additional 100+ seconds to make up the shortfall. The payload mass was about half of the projected GTO capacity, there should be quite a large margin. So why wouldn't the 2nd stage burn for extra longer time and ended up in the LEO at least?
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What is strange is that the flow is heading towards the front - I can't think of why (exosphere atmospheric effect?).
Recirculating of exhaust at high altitude. Happens on all launch vehicles, there are some good Saturn V images where it almost reaches the top of the first stage.
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I wonder if the second stage and its payload impacted somewhere east of Manlia in the PI?
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I wonder if the second stage and its payload impacted somewhere east of Manlia in the PI?
No, its trajectory was north of the Philippines, it would have to have been way off course.
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The incident is still openly discussed on other Chinese forums. So this may be a more of a Zhihu policy.
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Watch the video at 1:03:32 on. The lower stage separates then you see engine(s) fire up and gimballing then within seconds stop firing but you can still see gimballing going on. I'm not saying there wasn't a problem with the first stage I'm saying both stages had problems.
The upper stage might have issues as well, but the first stage must contain the root cause. The upper stage does seem to shut down quickly after the first start, but that might be caused by propellant settling issues due to atmospheric friction. Later the engines do seem to start(?) - but that glow is most likely from the re-entry. (The light looks very different than the short engine start at 1:03:38)
After reviewing the first CZ-5 launch, I'll have to change my mind. It looks like the upper stage does start and may actually continue running. The upper stage engines produce very little light, and the initial short light is only the startup and perhaps a combination with settling thrusters.
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I wonder if the second stage and its payload impacted somewhere east of Manlia in the PI?
No, its trajectory was north of the Philippines, it would have to have been way off course.
Then how about this video? https://www.youtube.com/watch?v=30RQlXgNgTQ (https://www.youtube.com/watch?v=30RQlXgNgTQ)
As for the Chinese booster being off course, the first stage appears to lose an engine and the second stage did not properly operate. After watching this and another video, wonder if it impacted within the Philipines?
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wonder if it impacted within the Philipines?
Page 5 has a screenshot at T+6:00 showing payload fairing drop zone well passed Philippine. Assuming things went OK until fairing, the 1st stage has no chance impacting Philippine. Page 6 has a screenshot showing the 2nd stage approaching Saipan. Likely the 1st stage reentered somewhere short of the projected range.
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Here are more images from Luzon.
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Those images look quite normal for what people would see for an eastward launch just after sunset. Compare to this video of the SpaceX SES-8 launch, it looked similar:
https://www.youtube.com/watch?v=GZpWIAVPdGo
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Lars-J So amazing with a bit more information and another long look I have to agree that what I thought was streaming down the rocket was actually coming from the core stage damage motor up the rocket and then back down.
Also took a good look at the upper stage ignition and although it looked liked it shut off, it didn't which becomes apparent once the stage orientates with the bright atmosphere behind it.
Although I was wrong I sure did enjoy the excercise and along the way learned a few more things. Thus a successful conclusion. This is why I have a lifetime membership for this site, loving it, thank you!
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That's killed our chances of a hi-res launch pic, I suppose :/
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Here are more images from Luzon.
Well, the picture from https://www.facebook.com/janrey.aquino06/posts/1745992502080840?pnref=story (https://www.facebook.com/janrey.aquino06/posts/1745992502080840?pnref=story) is dated July 2 4:46am (Manila local time) which would be July 1, 20:46 UTC some 15 hours before CZ-5 lift-off time ???
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Here are more images from Luzon.
Well, the picture from https://www.facebook.com/janrey.aquino06/posts/1745992502080840?pnref=story (https://www.facebook.com/janrey.aquino06/posts/1745992502080840?pnref=story) is dated July 2 4:46am (Manila local time) which would be July 1, 20:46 UTC some 15 hours before CZ-5 lift-off time ???
The witnesses report an observation time consistent with the launch. There are any number of reasons why the camera's internal clock might be set incorrectly. But I will ask!
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Here are more images from Luzon.
Well, the picture from https://www.facebook.com/janrey.aquino06/posts/1745992502080840?pnref=story (https://www.facebook.com/janrey.aquino06/posts/1745992502080840?pnref=story) is dated July 2 4:46am (Manila local time) which would be July 1, 20:46 UTC some 15 hours before CZ-5 lift-off time ???
The witnesses report an observation time consistent with the launch. There are any number of reasons why the camera's internal clock might be set incorrectly. But I will ask!
Sorry I wasn't clear enough: 4:46am is the time of the facebook post
Jan Rey Agulay Aquino added 3 new photos — with Cortez Plado Rita and 7 others.
July 2 at 4:46am
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Long March 5 Failure Casts Doubt On Chinese Space Schedule
Long March 5s, China’s largest rockets, are supposed to launch the Chang’e 5 lunar probe this year and the first module of China’s planned space station next year; the timing of both missions cannot now be assured. Furthermore, two other new Chinese launchers plus another soon to enter development share much technology with the Long March 5, notably engine components, raising the possibility that the launch failure has implications for them.
The payload of the failed mission was the Shijian 18 geostationary satellite, built on the DFH-5 bus, which was to go into orbit for the first time. Exploiting the capacity of the big new bus, Shijian 18 had a weight of 7 metric tons. Apart from quantum communications technology, it featured a new type of Hall-effect electric thruster
The unsuccessful mission was the fourth flight of the engine that provides the foundation for China’s new space launcher family, the kerosene-fueled YF-100. Development of the engine was completed years before it first flew on the smallest member of the family, Long March 6, in 2015. Long March 7, which has also flown, uses the same engine; Long March 8, which is almost ready for full-scale development, will use it too.
Long March 5 development was delayed by challenges in fabricating the 5-meter (11-ft.) diameter structure that carries the liquid hydrogen and liquid oxygen propellant of the core. YF-100s power the four boosters.
http://m.aviationweek.com/space/long-march-5-failure-casts-doubt-chinese-space-schedule
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As far as is known, the kerosene-fueled YF-100 engines worked as expected. So this event should not affect CZ-6 and CZ-7 missions.
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Is it possible for CAST to build a spare for Shijian 18? Is there a compelling need to?
Related question: I see from Gunter's Space Page that there MAY BE another DFH-5 bus satellite on order: APStar 6D. http://space.skyrocket.de/doc_sdat/apstar-6d.htm
Could this satellite be shifted to CZ-5 to provide a return to flight payload?
<snip>
Also, speculation question: Would Chang'e-5 remain as the next payload for Long March-5, or would another payload substitute for the CZ-5 return to flight?
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New images from the Philippines....
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Is it possible for CAST to build a spare for Shijian 18? Is there a compelling need to?
Related question: I see from Gunter's Space Page that there MAY BE another DFH-5 bus satellite on order: APStar 6D. http://space.skyrocket.de/doc_sdat/apstar-6d.htm
Could this satellite be shifted to CZ-5 to provide a return to flight payload?
<snip>
Also, speculation question: Would Chang'e-5 remain as the next payload for Long March-5, or would another payload substitute for the CZ-5 return to flight?
It is possibly a DFH-5 - the reports were not unambiguous.
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New images from the Philippines....
https://www.youtube.com/watch?v=GJhXlXb4Tv0
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There are some Chinese forum members who apparently observed that the flame from one of the core stage engines look dim and irregular as early as initalization of roll program a dozen or so seconds after liftoff - which might mean a bad engine (bad mixture ratio etc.).
Can someone check on that? I somehow can't see it. :-\
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More images and witness reports -- in Tagalog.
https://www.youtube.com/watch?v=twmFxKVwBcc
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Those images look quite normal for what people would see for an eastward launch just after sunset. Compare to this video of the SpaceX SES-8 launch, it looked similar:
Stabilized and speed up 2x James Farthing's cool video.
https://youtu.be/v37mBt7eXgc
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I think the curve in the plumes from Luzon is QUITE abnormal. It suggests to me that the rocket is slowly tumbling. Don't forget that the plume ejection speed [about 3 km/sec] may be less than the ground speed of the rocket so the plume could normally 'follow' the rocket with whatever delta-V each particle was given, depending on the changing orientation of the rocket. If the plume is seen expanding backwards it is another clue that the rocket ground speed is much less than planned. It's also possible that the curve is a sign of atmospheric resistance if the rocket is dropping towards the 100-km 'Karman Line'. Over Luzon at the moment the images were taken, Earth's shadow was about 200 km high.
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Look quite normal to me. It could be curved.
http://www.spacearchive.info/pegasus-xl-trace.htm (http://www.spacearchive.info/pegasus-xl-trace.htm)
Also no significant tumbling was visible in rocketcam as long as what is broadcasted.
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Look quite normal to me. It could be curved.
http://www.spacearchive.info/pegasus-xl-trace.htm (http://www.spacearchive.info/pegasus-xl-trace.htm)
Also no significant tumbling was visible in rocketcam as long as what is broadcasted.
Second point well made -- we need to get a lat/long/alt/time plot to correlate with aspect angles in the Luzon images.
First point -- not so fast, the curves on those images are endoatmospheric, below the Karman line. with wind shear. Once you start generating a plume in vacuum, entirely different rules of motion.
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Anybody working on this? -- we need to get a lat/long/alt/time plot to correlate with aspect angles in the Luzon images.
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more local Philippines sightings reports....
https://www.youtube.com/watch?v=kRsoMSj8fUw
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Is this phenomenon something that Filipino sky-watchers will have future opportunities to see and record, under the right lighting conditions--GTO/GEO launches from Wenchang?
Would those opportunities be predictable?
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Is this phenomenon something that Filipino sky-watchers will have future opportunities to see and record, under the right lighting conditions--GTO/GEO launches from Wenchang?
Would those opportunities be predictable?
Yes. Any launch just after sunset from Wenchang (most GTO launches) could produce a similar effect.
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Is this phenomenon something that Filipino sky-watchers will have future opportunities to see and record, under the right lighting conditions--GTO/GEO launches from Wenchang?
Would those opportunities be predictable?
Yes. Any launch just after sunset from Wenchang (most GTO launches) could produce a similar effect.
Or just before sunrise; and from most any launch site. Plenty of "UFO" sightings from our own proverbial back yard. For example, the MUOS 4 launch.
https://www.youtube.com/watch?v=7fR4g-9Pi0M (https://www.youtube.com/watch?v=7fR4g-9Pi0M)
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Tian: Long March 5 investigation ongoing, hope to have details by the end of the year. Will adjust schedules of Chang’e-5 and 4. #IAC2017
https://twitter.com/jeff_foust/status/912197913995911168 (https://twitter.com/jeff_foust/status/912197913995911168)
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Here’s the related article to the above tweet.
Long March 5 failure to postpone China’s lunar exploration program
A leading official of China’s space program confirmed Sept. 25 that the July failure of the country’s largest launch vehicle will lead to delays to upcoming lunar missions, including one to return samples.
Tian Yulong, secretary general of the China National Space Administration, said at a press conference during the 68th International Astronautical Congress here that the investigation into the July 2 failure of the Long March 5 on its second mission was ongoing, with no updates on the cause of the failure.
“The Long March 5 is a bigger challenge for China’s space agency,” he said. “In the future, maybe the end of the year, we will have a clear understanding of the problem.”
http://spacenews.com/long-march-5-failure-to-postpone-chinas-lunar-exploration-program/
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Interesting. Someone in 9ifly reminded me that the Xiang Yang Hong 09 survey vessel(support ship of the submarine Jiao Long) is just in the position of CZ-5 stage 1 crash. I just checked the satellite AIS, the current position of the ship is 139°34.08'E 16°49.91'N in 2017-10-03 04:28:38(UTC +8)
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Anyone who has subscription to Aviationweek? Came across this article or rather a synopsis of a news that the failure have been identified. The full article requires subscription, so I have not been able to read it in full.
http://aviationweek.com/space/long-march-5-fault-identified-other-launchers-unaffected (http://aviationweek.com/space/long-march-5-fault-identified-other-launchers-unaffected)
"Chinese space engineers have identified the fault that caused the failure of the second flight of their country’s largest space launcher, Long March 5, a problem that appears to be pushing back the mission schedule by about a year. The cause of the failure was simply a manufacturing defect in one of the two YF-77 hydrogen-burning engines of the core first stage, says a source close to the Chinese industry. The fault was quickly pinned down, says that source, who adds there was nothing ..."
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Is there a launch code available for this flight, please?
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Is there a launch code available for this flight, please?
Should be 07-W4
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Is there a launch code available for this flight, please?
Should be 07-W4
Agreed that is what is *should* be, but as far as I know the code for Tianzhou 1 hasn't been confirmed as being 07-W3.
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Sure. I just did some search work, and found nothing...
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It's 07-W3, I saw it with my own eyes
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It's 07-W3, I saw it with my own eyes
Are you sure? I highly doubt it
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It's 07-W3, I saw it with my own eyes
Are you sure? I highly doubt it
Possibly @linxiaoyi means they saw 07-W3 for Tianzhou 1 with their own eyes?
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Came across this article dated 27 Sept 2017:
https://thespacereporter.com/article.php?n=rocket-failure-causes-china-to-postpone-lunar-sample-return-mission&id=131684 (https://thespacereporter.com/article.php?n=rocket-failure-causes-china-to-postpone-lunar-sample-return-mission&id=131684)
There was a mentioned of a second Shijian-18. I assume the author meant a backup for the Shijian-18 that was lost. Scheduled for next month? Using the CZ-5 (Y3) that was initially meant for Chang'e 5? What do you think...just speculation by the author?
"Another Long March 5 launch scheduled for November might carry a second Shijian-18 satellite, replacing the first one, which was destroyed in the failed launch." (paragraph six of the article)
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If there is a launch next month, rocket stages should be transported to Wenchang right now. Could be verified by checking the whereabout of yuangwang21/22.
Edit: found Yuan Wang 21 anchored at Zhangjiagang.
https://www.fleetmon.com/vessels/yuan-wang-21_0_8295142/
Don't known where is Yuan Wang 22 right now.
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Previous information said that that launch was schedule for the second quarter of 2018.
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So if I understand this right, the replacement satellite for ill-fated Shijian-18 launch will be using CZ-5 (Y3) and will launch in the second quarter of 2018 in place of the originally scheduled Chang'e 5???
Came across this article dated 27 Sept 2017:
https://thespacereporter.com/article.php?n=rocket-failure-causes-china-to-postpone-lunar-sample-return-mission&id=131684 (https://thespacereporter.com/article.php?n=rocket-failure-causes-china-to-postpone-lunar-sample-return-mission&id=131684)
There was a mentioned of a second Shijian-18. I assume the author meant a backup for the Shijian-18 that was lost. Scheduled for next month? Using the CZ-5 (Y3) that was initially meant for Chang'e 5? What do you think...just speculation by the author?
"Another Long March 5 launch scheduled for November might carry a second Shijian-18 satellite, replacing the first one, which was destroyed in the failed launch." (paragraph six of the article)
Previous information said that that launch was schedule for the second quarter of 2018.
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So if I understand this right, the replacement satellite for ill-fated Shijian-18 launch will be using CZ-5 (Y3) and will launch in the second quarter of 2018 in place of the originally scheduled Chang'e 5???
Came across this article dated 27 Sept 2017:
https://thespacereporter.com/article.php?n=rocket-failure-causes-china-to-postpone-lunar-sample-return-mission&id=131684 (https://thespacereporter.com/article.php?n=rocket-failure-causes-china-to-postpone-lunar-sample-return-mission&id=131684)
There was a mentioned of a second Shijian-18. I assume the author meant a backup for the Shijian-18 that was lost. Scheduled for next month? Using the CZ-5 (Y3) that was initially meant for Chang'e 5? What do you think...just speculation by the author?
"Another Long March 5 launch scheduled for November might carry a second Shijian-18 satellite, replacing the first one, which was destroyed in the failed launch." (paragraph six of the article)
Previous information said that that launch was schedule for the second quarter of 2018.
i read the article and was wondering whether it is correct (launch in November 2017) because i cannot find other news about this. But it is probably not true as there is no evidence that the CZ-5 (Y3) had already being transported to Wenchang as posted by zhangdmev (thanks). If i am correct Zhangjiagang port is not anywhere near Tianjin. (Nevertheless, the whereabout of the yuangwang 22 is not known...anyone has idea where it is?)
If there is a launch next month, rocket stages should be transported to Wenchang right now. Could be verified by checking the whereabout of yuangwang21/22.
Edit: found Yuan Wang 21 anchored at Zhangjiagang.
https://www.fleetmon.com/vessels/yuan-wang-21_0_8295142/
Don't known where is Yuan Wang 22 right now.
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So if I understand this right, the replacement satellite for ill-fated Shijian-18 launch will be using CZ-5 (Y3) and will launch in the second quarter of 2018 in place of the originally scheduled Chang'e 5???
Came across this article dated 27 Sept 2017:
https://thespacereporter.com/article.php?n=rocket-failure-causes-china-to-postpone-lunar-sample-return-mission&id=131684 (https://thespacereporter.com/article.php?n=rocket-failure-causes-china-to-postpone-lunar-sample-return-mission&id=131684)
There was a mentioned of a second Shijian-18. I assume the author meant a backup for the Shijian-18 that was lost. Scheduled for next month? Using the CZ-5 (Y3) that was initially meant for Chang'e 5? What do you think...just speculation by the author?
"Another Long March 5 launch scheduled for November might carry a second Shijian-18 satellite, replacing the first one, which was destroyed in the failed launch." (paragraph six of the article)
Previous information said that that launch was schedule for the second quarter of 2018.
i read the article and was wondering whether it is correct (launch in November 2017) because i cannot find other news about this. But it is probably not true as there is no evidence that the CZ-5 (Y3) had already being transported to Wenchang as posted by zhangdmev (thanks). If i am correct Zhangjiagang port is not anywhere near Tianjin. (Nevertheless, the whereabout of the yuangwang 22 is not known...anyone has idea where it is?)
If there is a launch next month, rocket stages should be transported to Wenchang right now. Could be verified by checking the whereabout of yuangwang21/22.
Edit: found Yuan Wang 21 anchored at Zhangjiagang.
https://www.fleetmon.com/vessels/yuan-wang-21_0_8295142/
Don't known where is Yuan Wang 22 right now.
could be somewhere in dry dock.
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Both Yuan Wang 21 and 22 anchored at Jiangyin, Jiangsu as of Oct. 12
In addition to the investigation of CZ-5's failure, the manufacture of SJ-18 02 will take a few time. There is no way CZ-5 Y3 will launch in the coming months
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Interesting. Someone in 9ifly reminded me that the Xiang Yang Hong 09 survey vessel(support ship of the submarine Jiao Long) is just in the position of CZ-5 stage 1 crash. I just checked the satellite AIS, the current position of the ship is 139°34.08'E 16°49.91'N in 2017-10-03 04:28:38(UTC +8)
One of my sources confirmed that they were looking for the debris of this launch, but they hadn't made a final decision whether to salvage it or not
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Interesting. Someone in 9ifly reminded me that the Xiang Yang Hong 09 survey vessel(support ship of the submarine Jiao Long) is just in the position of CZ-5 stage 1 crash. I just checked the satellite AIS, the current position of the ship is 139°34.08'E 16°49.91'N in 2017-10-03 04:28:38(UTC +8)
One of my sources confirmed that they were looking for the debris of this launch, but they hadn't made a final decision whether to salvage it or not
Is it normal for the administration to salvage components (in this case the CZ-5 stage 1) after a failed launch?
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Latest news about the CZ-5 (Y2) failure. The article mentioned about an interview with the Exec Vice President of GCWIC,Fu Ziheng in Tokyo on 11 October 2017.
https://www.spaceintelreport.com/china-great-wall-industry-corp-bumpy-year-satellite-launches-returning-flight/ (https://www.spaceintelreport.com/china-great-wall-industry-corp-bumpy-year-satellite-launches-returning-flight/)
"At the APSCC conference here on Oct. 11, China Great Wall Industry Corp. (GCWIC) Executive Vice President Fu Ziheng discussed the status the post-failure investigations." (para 2)
"What was the cause of this underperformance?
...After the failure we suspended all Long March launches, including LEO and GEO. During the past few months all the work has been done and we can say that for Long March 5 it is a problem with first-stage propulsion. Right now all the correction work is ongoing because Long March 5 is going to be used for Chinese government missions including lunar missions." (para 10)
"The Long March 5 first-stage propulsion problem was a design issue or a manufacturing issue?
The inquiry process is still ongoing." (para 13)
Reading the article, i seems to have the impression that the engineers have found the fault and they are making the corrections. But it looks like when pressed to state officially the caused, Mr Fu does not want to say.
This article also confirms that they have resolved the issue with the Long March 3B failure.
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Interesting. Someone in 9ifly reminded me that the Xiang Yang Hong 09 survey vessel(support ship of the submarine Jiao Long) is just in the position of CZ-5 stage 1 crash. I just checked the satellite AIS, the current position of the ship is 139°34.08'E 16°49.91'N in 2017-10-03 04:28:38(UTC +8)
One of my sources confirmed that they were looking for the debris of this launch, but they hadn't made a final decision whether to salvage it or not
Is it normal for the administration to salvage components (in this case the CZ-5 stage 1) after a failed launch?
After the failure of H-II F8, Japanese salvaged the debris of S1s engine for investigation. But for Chinese, it may be the first time to do it
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OK it's "rumors" time on what happened with the YF-77: this rumor (http://bbs.9ifly.cn/forum.php?mod=redirect&goto=findpost&ptid=88828&pid=566649) (actually posted a few weeks ago) points to the problem being one of the engine's turbopump rotor shaft's enclosure cap falling off and blocked the propellant flow after it fell into the propellant feedline.
Also here is someone who claimed to have spoken with CZ-5 program director Li Dong yesterday (http://bbs.9ifly.cn/forum.php?mod=redirect&goto=findpost&ptid=88828&pid=569503):
1. The cause of this failure has been pinpointed and SASTIND will make a public statement soon.
2. Modifications to the engine have been designed. The next step will be to test and certify the modifications.
3. Next flight of the CZ-5 will be (per his personal estimation) before late 2018. (Launching by mid-2018 will be tight due to the need to test the modifications)
4. No upgrades to the CZ-5 (YF-100K, ability of the 2nd stage to make 3+ burns) will be introduced until after the whole launcher is in a mature state.
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For discussion and critiques here's my report on the Philippines observations of the failure and how ultimately disappointing they were.
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Long March 5 update: The fault behind the July failure has been identified & effective measures taken. However, the fault itself has not been disclosed. 3rd flight will be by/near end of 2018 http://news.sina.com.cn/c/nd/2018-01-15/doc-ifyqptqv9660647.shtml … (中文)
https://twitter.com/AJ_FI/status/952866589736611840 (https://twitter.com/AJ_FI/status/952866589736611840)
The new info comes from Tao Gang, general manager of Tianjin Long March Launch Vehicle Manufacturing Co, which produces the CZ-5. Tao adds mass production of active rockets will be one of the main tasks for 2018, together with start of R&D on next-gen launchers.
https://twitter.com/AJ_FI/status/952867745993056256 (https://twitter.com/AJ_FI/status/952867745993056256)
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The Chinese have finally officially reported on the failure cause 9.5 months after the launch. The 1st stage engine no. 1's turbopump exhaust structure was blamed for failing under "complex thermal conditions" which fatally reduced its thrust at T+346 seconds. They also reported that the redesigned YF-77 have already been test fired multiple times by now with satisfactory results.
Chang'e 5 will go up on flight 4 after the RTF later this year.
Source (http://www.xinhuanet.com/2018-04/16/c_129851299.htm)
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http://www.xinhuanet.com/english/2018-04/16/c_137114990.htm
China to launch Long March-5 Y3 rocket in late 2018
BEIJING, April 16 (Xinhua) -- China plans to launch its heavy-lift carrier rocket, the Long March-5 Y3, in late 2018, after finding the cause of the failure of the Long March-5 Y2, according to the State Administration of Science, Technology and Industry for National Defense.
The Long March-5 Y2 rocket was launched from Wenchang Space Launch Center in the southern province of Hainan on July 2, 2017, but a malfunction happened less than six minutes after liftoff.
Analysis based on computer simulations and ground tests showed that a problem occurred in a turbine exhaust device in the engine of the first stage of the rocket, the administration said Monday.
The engine has been improved and has passed many ground tests. The research team is producing the Long March-5 Y3 rocket, according to the administration.
If the Long March-5 Y3 rocket is successful, the Long March-5 Y4 rocket will be used to launch the Chang'e-5 lunar probe, which is expected to bring lunar samples back to Earth.
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China reveals cause of Long March 5 failure; lunar sample mission to follow return-to-flight
Some article highlights.
The State Administration for Science, Technology and Industry for National Defense (SASTIND), which oversees China’s space activities, released a report April 16 attributing the failure to a turbopump on one of two liquid-oxygen and hydrogen YF-77 engines powering the rocket’s first stage.
The turbopump’s exhaust structure, according to SASTIND, failed while under “complex thermal conditions.”
Redesigned YF-77 engines have already been through hot fire testing at a site in a ravine near Xi’an in north China. The tests have verified the effectiveness of the measures taken, according to the report.
The return to flight is to take place late in the year, with previous space industry statements pointing to November.
Instead, the third Long March 5 will carry an experimental telecommunications satellite named Shijian-20, or “Practice-20” in Chinese, based on a new, large DFH-5 satellite platform, similar to the Shijian-18 satellite lost in July.
The SASTIND report states that the fourth Long March 5 will now carry the Chang’e-5 lunar sample return mission, launching in 2019. The mission will be the first of its kind for more than four decades and aims to collect around 2 kilograms of regolith from a site close to Mons Rümker in Oceanus Procellarum in the northwest of the moon’s near side.
A successful return to flight of the Long March 5 would also pave the way for the test launch of the Long March 5B, a variant developed for low Earth orbit launches and tasked with lofting 20 metric ton modules for a planned space station. The 5B is slated to perform its test flight around June 2019, according to a statement in March from theChina Manned Space Engineering Office.
http://spacenews.com/china-reveals-cause-of-long-march-5-failure-lunar-sample-mission-to-follow-return-to-flight/
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The Chinese have finally officially reported on the failure cause 9.5 months after the launch. The 1st stage engine no. 1's turbopump exhaust structure was blamed for failing under "complex thermal conditions" which fatally reduced its thrust at T+346 seconds. ....
Well, you nailed it last year: "What is sure is that all went wrong at 10:49 (T+5:44) when the left engine plume catastrophically turned into gas venting - that fits in with the rumored time that the 1st stage engine #1's turbopump went down." You were off by two whole seconds. Attaboy!!!