Author Topic: Ariane 5 VA241 -SES-14 (with NASA GOLD payload) & Al Yah-3 Jan. 25, 2018 UPDATES  (Read 240289 times)

Offline hartspace

  • Full Member
  • ***
  • Posts: 320
  • Liked: 297
  • Likes Given: 149
Since it took so long for the satellite control centers to find the two satellites, they are almost assuredly in the wrong orbit.  How wrong will determine if this is recoverable or not.

Offline Flying Beaver

Hmmm... it sounds like maybe on orbit, but not the correct orbit? What could potentially be the cause of that?

Exactly. Could still be in some kind of unstable LEO for all we know.

They were at 195 km altitude and 7.02 Km/s velocity at TLM cutoff.  If it was a propulsion problem, they could be in a (really) low orbit.

Would need more than a minute or two more of powered flight to loft the descending trajectory and achieve orbit. Good to remember the low T/W ratio of a fully fueled ECA, and the low relative velocity to the suborbital core stage so soon after sep.

Edit: Press release was deleted and formatting updated and then re-posted a couple minutes later.
« Last Edit: 01/26/2018 12:27 am by Flying Beaver »
Watched B1019 land in person 21/12/2015.

Offline pb2000

  • Full Member
  • ****
  • Posts: 671
  • Calgary, AB
  • Liked: 759
  • Likes Given: 237
Hmmm... it sounds like maybe on orbit, but not the correct orbit? What could potentially be the cause of that?

Exactly. Could still be in some kind of unstable LEO for all we know.

If ESC-A was able to release SES-14, then the Sylda, then Al Yah-3 it must have worked to some degree.

If the engine failed right when the telemetry was lost the sats probably would be lost by now.

(Edit: If someone knows better, please correct me!)
The core stage burns for an eternity compared to most launchers, so it might be in an orbit that the payloads could at least stabilize themselves and maybe in a few years get a rescue mission to boost them up. That being said, I'm still hopeing for a faulty datastream and the orbits are good.
« Last Edit: 01/26/2018 12:29 am by pb2000 »
Launches attended: Worldview-4 (Atlas V 401), Iridium NEXT Flight 1 (Falcon 9 FT), PAZ+Starlink (Falcon 9 FT), Arabsat-6A (Falcon Heavy)
Pilgrimaged to: Boca Chica (09/19 & 01/22)

Offline Flying Beaver

Strange that the objects (ECA, sats and adaptor) have not yet been tracked.
Usually happens within two hours of launch.
Watched B1019 land in person 21/12/2015.

Offline hartspace

  • Full Member
  • ***
  • Posts: 320
  • Liked: 297
  • Likes Given: 149
Strange that the objects (ECA, sats and adaptor) have not yet been tracked.
Usually happens within two hours of launch.
If they are in the wrong orbit, it may take a while to figure out what orbit they are in.

Offline Steven Pietrobon

  • Member
  • Senior Member
  • *****
  • Posts: 39218
  • Adelaide, Australia
    • Steven Pietrobon's Space Archive
  • Liked: 32738
  • Likes Given: 8196
Success!

"Stéphane Israël
‏ @arianespaceceo
41m41 minutes ago

VA241 update: lack of telemetry after ignition of the upper stage lasted the rest of powered flight. Both satellites confirmed separated, acquired, on orbit. SES-14 and Al Yah 3 communicating with their respective control centers. Both missions continuing"

https://twitter.com/arianespaceceo/status/956698000004395008
Akin's Laws of Spacecraft Design #1:  Engineering is done with numbers.  Analysis without numbers is only an opinion.

Offline Flying Beaver

Strange that the objects (ECA, sats and adaptor) have not yet been tracked.
Usually happens within two hours of launch.
If they are in the wrong orbit, it may take a while to figure out what orbit they are in.

Yep. With nominal launch, the trajectory is known in advance and tracking assets can be pointed correctly. Could be a symptom of off-nominal performance. 
« Last Edit: 01/26/2018 01:05 am by Flying Beaver »
Watched B1019 land in person 21/12/2015.

Offline DaveS

  • Shuttle program observer
  • Senior Member
  • *****
  • Posts: 8526
  • Sweden
  • Liked: 1199
  • Likes Given: 65
Success!

"Stéphane Israël
‏ @arianespaceceo
41m41 minutes ago

VA241 update: lack of telemetry after ignition of the upper stage lasted the rest of powered flight. Both satellites confirmed separated, acquired, on orbit. SES-14 and Al Yah 3 communicating with their respective control centers. Both missions continuing"

https://twitter.com/arianespaceceo/status/956698000004395008
Too early to say that. It's also just a repost of the Arianespace press-release: http://www.arianespace.com/press-release/va241/

That is what has been discussed right now, what kind of orbit did the ESC-A deploy them in? Nominal planned or lower than expected?
"For Sardines, space is no problem!"
-1996 Astronaut class slogan

"We're rolling in the wrong direction but for the right reasons"
-USA engineer about the rollback of Discovery prior to the STS-114 Return To Flight mission

Online Chris Bergin

My head is spinning. Many thanks to Steven and Zach for the great coverage. Obviously we need to keep following this one up.

Support NSF via L2 -- Help improve NSF -- Site Rules/Feedback/Updates
**Not a L2 member? Whitelist this forum in your adblocker to support the site and ensure full functionality.**

Offline Steven Pietrobon

  • Member
  • Senior Member
  • *****
  • Posts: 39218
  • Adelaide, Australia
    • Steven Pietrobon's Space Archive
  • Liked: 32738
  • Likes Given: 8196
Too early to say that. It's also just a repost of the Arianespace press-release: http://www.arianespace.com/press-release/va241/

Yes, they did not say if they were in the correct orbit. At 7 km/s at 200 km, that is 0.8 km/s short of orbit, so the ESC-A must have continued for at least that amount of delta-V.
Akin's Laws of Spacecraft Design #1:  Engineering is done with numbers.  Analysis without numbers is only an opinion.

Offline Flying Beaver

Yahsat's press release a copy-paste from ArianeSpace.

http://www.journeyofpride.com/ariane-5-launch-va241-for-ses-14-and-al-yah-3-update/

OrbATK (builder of Al Yah-3) then retweeted it.

« Last Edit: 01/26/2018 02:20 am by Flying Beaver »
Watched B1019 land in person 21/12/2015.

Offline Flying Beaver

The BBC's science correspondent Jonathan Amos sums up the current situation very well.

http://www.bbc.com/news/science-environment-42623297
Watched B1019 land in person 21/12/2015.

Offline MATTBLAK

  • Elite Veteran & 'J.A.F.A'
  • Senior Member
  • *****
  • Posts: 5362
  • 'Space Cadets' Let us; UNITE!! (crickets chirping)
  • New Zealand
  • Liked: 2239
  • Likes Given: 3883
So all good then? In the end, I mean :o
« Last Edit: 01/26/2018 02:26 am by MATTBLAK »
"Those who can't, Blog".   'Space Cadets' of the World - Let us UNITE!! (crickets chirping)

Online envy887

  • Senior Member
  • *****
  • Posts: 8144
  • Liked: 6801
  • Likes Given: 2965
So all good then?  :o
Losing telemetry isn't good, and we don't know if the orbits are nominal. But definitely better than the alternatives.

Offline e of pi

  • Full Member
  • ****
  • Posts: 723
  • Pittsburgh, PA
  • Liked: 297
  • Likes Given: 406
Yahsat's press release just a copy-paste from ArianeSpace.

http://www.journeyofpride.com/ariane-5-launch-va241-for-ses-14-and-al-yah-3-update/

OrbATK (builder of SES-14) then retweeted it.
At least they didn't refer all questions to SpaceX.

Offline ww2planes1

  • Member
  • Posts: 16
  • Liked: 1
  • Likes Given: 1
OrbATK (builder of SES-14) then retweeted it.
Correction, OATK build Al Yah 3.  Airbus built SES-14.


I saw further up in the thread that this was the first SSTO mission for Ariane.  Does anyone know why this mission was SSTO?  I didn't hear a technical reason for why on the live stream.  I was under the impression a super synchronous orbit could help reduce the Delta-V if an inclination change was required (like a SpaceX mission from Florida), but that clearly isn't the reason this time.

Offline yokem55

  • Full Member
  • ****
  • Posts: 653
  • Oregon (Ore-uh-gun dammit)
  • Liked: 468
  • Likes Given: 13
OrbATK (builder of SES-14) then retweeted it.
Correction, OATK build Al Yah 3.  Airbus built SES-14.


I saw further up in the thread that this was the first SSTO mission for Ariane.  Does anyone know why this mission was SSTO?  I didn't hear a technical reason for why on the live stream.  I was under the impression a super synchronous orbit could help reduce the Delta-V if an inclination change was required (like a SpaceX mission from Florida), but that clearly isn't the reason this time.
Probably so that SES-14 could get on station faster since it's an all electric bird.

Offline Steven Pietrobon

  • Member
  • Senior Member
  • *****
  • Posts: 39218
  • Adelaide, Australia
    • Steven Pietrobon's Space Archive
  • Liked: 32738
  • Likes Given: 8196
Yahsat update, in arabic I think.

http://www.journeyofpride.com/ar/%D8%AA%D8%AD%D8%AF%D9%8A%D8%AB-%D8%AE%D8%A8%D8%B1%D9%8A-%D9%84%D8%A5%D8%B7%D9%84%D8%A7%D9%82-%D8%A7%D9%84%D8%B5%D8%A7%D8%B1%D9%88%D8%AE-%D8%A3%D8%B1%D9%8A%D8%A7%D9%86-5-%D8%A7%D9%84%D8%AD%D8%A7%D9%85/

"The carrier rocket was launched satellite Eliah 3 on 25 January 2018 at 7:20 pm. After a few seconds of launching the rocket, the upper part of the engine did not receive the second tracking station, located in Natal-Brazil, telemetry data.

Interruption of the missile tracking data for the duration of the flight. Later, he was sure separation of satellites of the rocket to initiate the walk in space orbit control technical group. Right now is controlled by satellites SAS-14 kept him 3 through their respective command centers. We would like to confirm the progress of satellite access campaign happenings to tropical locations."
Akin's Laws of Spacecraft Design #1:  Engineering is done with numbers.  Analysis without numbers is only an opinion.

Offline DaveS

  • Shuttle program observer
  • Senior Member
  • *****
  • Posts: 8526
  • Sweden
  • Liked: 1199
  • Likes Given: 65
Yahsat update, in arabic I think.

http://www.journeyofpride.com/ar/%D8%AA%D8%AD%D8%AF%D9%8A%D8%AB-%D8%AE%D8%A8%D8%B1%D9%8A-%D9%84%D8%A5%D8%B7%D9%84%D8%A7%D9%82-%D8%A7%D9%84%D8%B5%D8%A7%D8%B1%D9%88%D8%AE-%D8%A3%D8%B1%D9%8A%D8%A7%D9%86-5-%D8%A7%D9%84%D8%AD%D8%A7%D9%85/

"The carrier rocket was launched satellite Eliah 3 on 25 January 2018 at 7:20 pm. After a few seconds of launching the rocket, the upper part of the engine did not receive the second tracking station, located in Natal-Brazil, telemetry data.

Interruption of the missile tracking data for the duration of the flight. Later, he was sure separation of satellites of the rocket to initiate the walk in space orbit control technical group. Right now is controlled by satellites SAS-14 kept him 3 through their respective command centers. We would like to confirm the progress of satellite access campaign happenings to tropical locations."
That sounds like the Arianespace press-release. It's just been mangled by having first been translated to Arabic and then run through a machine translator back to English.
"For Sardines, space is no problem!"
-1996 Astronaut class slogan

"We're rolling in the wrong direction but for the right reasons"
-USA engineer about the rollback of Discovery prior to the STS-114 Return To Flight mission

Offline Steven Pietrobon

  • Member
  • Senior Member
  • *****
  • Posts: 39218
  • Adelaide, Australia
    • Steven Pietrobon's Space Archive
  • Liked: 32738
  • Likes Given: 8196
That sounds like the Arianespace press-release. It's just been mangled by having first been translated to Arabic and then run through a machine translator back to English.

The post has "satellite access campaign happenings to tropical locations" which I think is new, but we already know the satellites are in a near equatorial orbit. If the apogee is low, this would mean greater use of ground stations near the equator.
« Last Edit: 01/26/2018 02:58 am by Steven Pietrobon »
Akin's Laws of Spacecraft Design #1:  Engineering is done with numbers.  Analysis without numbers is only an opinion.

Tags:
 

Advertisement NovaTech
Advertisement Northrop Grumman
Advertisement
Advertisement Margaritaville Beach Resort South Padre Island
Advertisement Brady Kenniston
Advertisement NextSpaceflight
Advertisement Nathan Barker Photography
0