NASASpaceFlight.com Forum
Commercial and US Government Launch Vehicles => ULA - Delta, Atlas, Vulcan => Topic started by: beidou on 10/08/2012 09:49 pm
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This will be the first launch of the three GPS IIF launches in 2013.
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GPS IIF-4 is Atlas V not Delta IV. It will be the first GPS launch on an Atlas.
Thanks for pointing this out.
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From the Boeing website (http://www.boeing.com/defense-space/space/bss/launch/launch_sched.html), there is no GPS IIF-4, which is probably a satellite for internal testing only? Maybe the next GPS satellite launch is GPS IIF-5.
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From the Boeing website (http://www.boeing.com/defense-space/space/bss/launch/launch_sched.html), there is no GPS IIF-4, which is probably a satellite for internal testing only? Maybe the next GPS satellite launch is GPS IIF-5.
It is erroneously listed there as GPS IIF SV-3
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GPS IIF-1 is SV-1, GPS IIF-2 is SV-2 and GPS IIF-3 is SV-4. The satellites were not launched in the order of manufacture.
So the next launch (GPS IIF-4) might very well feature SV-3 which was sidelined for additional work.
--- CHAS
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It will be the first GPS launch on an Atlas.
No, just the first one in a very long time. Eleven Block I GPS satellites were launched by Atlas-E/F rockets between 1978 and 1985.
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Does anyone know the serial number of the Atlas-V?
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AV039
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currently scheduled on May 15 with launch window: 17:39-17:58 UTC
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currently scheduled on May 15 with launch window: 17:39-17:58 UTC
Actually that's EDT. ;) (2139 - 2158Z)
Do we know what satellite it will replace? There are quite a few GPS satellites working well beyond their lifetimes by now....
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any updates on this mission?
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any updates on this mission?
Check out the mission booklet!
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So from http://www.gpsworld.com/gps-block-iif-4-launch-set-may-15/ (http://www.gpsworld.com/gps-block-iif-4-launch-set-may-15/), GPS IIF-4 is SVN66 and will head for slot C-2, replacing GPS IIA-25 (SVN33) launched on March 28, 1996. That one will remain as a reserve satellite.
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That is the launch base processing patch, not the launch vehicle or spacecraft.
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ULA:
Everything is progressing for the Air Force’s Global Positioning System (GPS) IIF-4 launch. The mission is set to liftoff on a ULA Atlas V on Wednesday, May 15 from Space Launch Complex 41 at Cape Canaveral Air Force Station in Florida. The 18-minute launch window opens at 5:38 p.m. EDT. Today’s L-3 forecast shows an 80 percent chance of favorable weather conditions for launch. I have included the mission booklet for information regarding this mission.
Weather Forecast
Overall probability of violating weather constraints: 20%
Primary concern(s): Cumulus Clouds
Overall probability of violating weather constraints for 24 hour delay: 20%
Primary concern(s): Cumulus Clouds
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ULA @ulalaunch 12h
Take 2: The webcast for Wednesday's #GPSIIF-4 launch will start at 5:18 p.m. EDT, launch window opens at 5:38 p.m. http://ow.ly/l00mg
Retweeted 9 times
8:31 PM - 13 May 13
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There is an Atlas at the pad
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There is an Atlas at the pad
Did you get to work on this payload Jim?
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This would make a good mission badge. ;)
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There is an Atlas at the pad
Did you get to work on this payload Jim?
USAF mission, only work NASA
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The ULA Atlas V vehicle was rolled to the launch pad this morning in preparation for tomorrow’s Air Force Global Positioning System (GPS) IIF-4 launch. The mission is set to liftoff on Wednesday, May 15 from Space Launch Complex 41 at Cape Canaveral Air Force Station in Florida. The 18-minute launch window opens at 5:38 p.m. EDT. Today’s L-1 forecast continues to show an 80 percent chance of favorable weather conditions for launch.
Cape Canaveral Air Force Station, Fla. (May 14, 2013) - A United Launch Alliance Atlas V rolls out for launch at Space Launch Complex-41 with the Air Force’s Global Positioning System (GPS) IIF-4 spacecraft. Launch is set for Wednesday, May 15 at 5:38 p.m. at the opening of the 18-minute window. GPS IIF-4 is the fourth in a series of next generation GPS satellites and will join a worldwide timing and navigation system utilizing 24 satellites in six different planes, with a minimum of four satellites per plane positioned in orbit approximately 11,000 miles above the earths’ surface.
Photo by Pat Corkery, United Launch Alliance
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Does anybody know why the Centaur is completely unpainted for this launch? Never seen this before!
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Does anybody know why the Centaur is completely unpainted for this launch? Never seen this before!
It is typically done for long duration missions where thermal management of Centaur Cryo is a requirement. NASA typically now just uses white Centaur.
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Moved for live coverage.
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William Graham with the launch preview. Always worth a read:
http://www.nasaspaceflight.com/2013/05/ula-atlas-v-launch-new-gps-satellite/
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Good article.
GPS IIF-4 has Space Vehicle Number (SVN) 66. It will use PRN-27; a signal modulation previously used by USA-84, or GPS IIA-6 (SVN-27), a twenty-year-old satellite which was retired from service last October.
PRN-27 has also been broadcast (albeit not marked healthy or included in the almanacs) by SVN-49 in the meantime. Was that thought just to be confusing the issue?
-Bob
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Good article.
GPS IIF-4 has Space Vehicle Number (SVN) 66. It will use PRN-27; a signal modulation previously used by USA-84, or GPS IIA-6 (SVN-27), a twenty-year-old satellite which was retired from service last October.
PRN-27 has also been broadcast (albeit not marked healthy or included in the almanacs) by SVN-49 in the meantime. Was that thought just to be confusing the issue?
-Bob
Apparently moved to PRN30 last week: http://www.gps-forums.net/notice-advisory-navstar-users-nanu-2013029-nanu-type-general-t44712.html (http://www.gps-forums.net/notice-advisory-navstar-users-nanu-2013029-nanu-type-general-t44712.html)
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Launch site
Spacecraft
Launch Vehicle
patches
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@ JIm,
The spacecraft crew are clearly comic nerds of a considerable scale. I approve. ;D
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InsideKSC@InsideKSC
The Atlas V with #GPSIIF4 at CCAFS SLC-41, moments ago. Launch NET 5:38 p.m. EDT. pic.twitter.com/uDJjXUUkZ2
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ULA@ulalaunch
90% chance of favorable weather for today's #GPSIIF4 #satellite launch on an #AtlasV. Launch window opens at 5:38 p.m. EDT.
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ULA@ulalaunch
The #GPSIIF4 count is now in a planned 30-min hold at T-2 hours. This is the first of two planned holds in the count #AtlasV
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ULA's web video had sound up and a slide just a while ago.
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ULA@ulalaunch
The poll for cryogenic fueling is complete, and the team has the go to begin fueling operations. Count has resumed at T-2 hours. #GPSIIF4
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ULA:
Everything is progressing for the launch at 5:38 p.m. The launch team gave a go to fuel the vehicle and that operation will begin shortly. The forecast now shows a 90 percent chance of favorable weather for launch.
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T-2h
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Anyone know the plan to dispose of the Centaur after releasing the satellite? The planned burns total 14:16 . Combining the fuel mass, the ISP, and the thrust would indicate the Centaur could run for 15:30 if it used every last drop and none evaporated on the way up. So there might be quite a bit of delta-V left over if the Centaur works normally.
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O2 tanking...
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Launch team has received the "go" to begin filling the Centaur upper stage with the supercold fuel.
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Centaur LH2 tanking.
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60 minutes for launch...
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ULA: Just an hour from launch and the team is not currently working any technical issues for the launch at 5:38 p.m. EDT.
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Approximately one hour from the opening of the #GPSIIF4 launch window and the team is not working any technical issues #AtlasV
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Topping in works.
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ULA webcast set to begin in about 25 mins:
http://www.ulalaunch.com/site/pages/Webcast.shtml
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I prefer Jim's patches.
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Getting closer to launch.
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Looks like someone was messing with the camera! :P
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We're getting a little more water view now.
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Entering planned 25 minute hold.
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L-20 mins.
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On an unrelated note, this guy has a pretty cool tie.
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Sat pics:
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No issues being worked.
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Weather green.
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Fairing:
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Rollout with the cool trains (I know they aren't actually trains).
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I hope this is right! :)
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L-12 mins.
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Does centaur not do an orbit-lowering burn?
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Controllers and management:
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Radiation parameters acceptable.
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Terminal Count status check next.
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Communications check.
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L-8 mins.
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Final polling about to begin.
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Final polling to come out of the hold.
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All go to proceed.
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Go to come out of the hold!
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We're ready to go!
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120 seconds until the hold is released.
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Go Atlas Go Centaur
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T-4 minutes and counting.
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T-4 mins and COUNTING.
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4 minute hold lifted.
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That's a big bird.
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Fly Bird fly....
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How comes this launch is going on a baseline 401 yet the last launch was on an augmented Delta IV?
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Atlas tanks securing.
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FTS Internal.
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T-120 seconds.
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T-120 seconds.
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T-2:00
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Vehicle on internal power.
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Launch sequence start.
Securing the tanks.
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Centaur tanks securing. FTS armed.
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Launch enable. Range Green.
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60 seconds.
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T-60 seconds.
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T-60 seconds.
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Status Check: Go Atlas! Go Centaur!
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20 seconds.
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Launch!!!
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LAUNCH!!!
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LAUNCH!!
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Max Q.
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Always a great shot during first stage.
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Speed 1858 mph.
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And this:
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Closed loop steering.
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Marty does a great job with status without all the "nominal' calls.
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MECO!
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STAGING:
1-2 Sep:
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Faring jettison.
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Fairing Jettison
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Good Centaur performance.
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Where is the Centaur going on this flight once it has delivered the GPS?
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10 mins to MECO-1 on the Centaur.
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Next MECO in less than 10 minutes.
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Interview time.
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Inclination is slowly increasing so a slight yaw maneuver is in work.
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Around 6 minutes til next MECO.
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Back on track.
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Looking good.
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From the trajectory parameters on screen, looks like it's in orbit now.
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inclination is stable at 55 degrees
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From Valkaria Airport
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MECO about a minute away.
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MECO.
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MECO!
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Good work JAFO.
First burn complete.
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Three hours to the second burn.
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Why a three hour coast phase?
That seems exceptionally long.
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Thanks for the super coverage
97.36%
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Lt. Pond comes across as a great guy.
ULA Webcast ending until the end of the coast.
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Launch replay.
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Good coverage everyone. Makes sure you're all back here in three hours ;)
William's article, updated:
http://www.nasaspaceflight.com/2013/05/ula-atlas-v-launch-new-gps-satellite/
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10,980X90 NM orbit at 55 degrees. There were no target parameters for this stage in the mission guide
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Why a three hour coast phase?
That seems exceptionally long.
You are used to missions where MECO-1 leaves you in low LEO,
200 x 200 km or so, and then the second burn is to GTO (with a much later apogee burn to get to final orbit). So the coast phase then is just to get perigee on the equator, doesn't take long to get there.
But on this mission Atlas flew straight from the pad to transfer orbit,
167 x 20200 km x 55 deg. The second burn will circularize at 20200 km for the final target orbit. So the coast phase is just half the transfer orbit period - three hours is not bad to coast from 200 km or so all the way up to 20000 km or so.
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Good coverage everyone. Makes sure you're all back here in three hours ;)
William's article, updated:
http://www.nasaspaceflight.com/2013/05/ula-atlas-v-launch-new-gps-satellite/
I'll try my best to be here.
Looking forward to next weeks launch.
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Lt. Pond comes across as a great guy.
He's an AF Lt ;D
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Why a three hour coast phase?
That seems exceptionally long.
You are used to missions where MECO-1 leaves you in low LEO,
200 x 200 km or so, and then the second burn is to GTO (with a much later apogee burn to get to final orbit). So the coast phase then is just to get perigee on the equator, doesn't take long to get there.
But on this mission Atlas flew straight from the pad to transfer orbit,
167 x 20200 km x 55 deg. The second burn will circularize at 20200 km for the final target orbit. So the coast phase is just half the transfer orbit period - three hours is not bad to coast from 200 km or so all the way up to 20000 km or so.
Thanks for that clarification. This site is great for learning stuff like this. :)
Was there any particular reason why they used a baseline 401 on this mission, considering the past launchers used for GPS?
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How comes this launch is going on a baseline 401 yet the last launch was on an augmented Delta IV?
The Atlas V 401 has a better performance than the Delta IV Medium. For a GTO with delta-V to GSO = 1800 m/s:
AV 401: 4750 kg
DIVM: 4540 kg
DIVM+4/2: 6270 kg
So the performance required to lift the GPS IIF satellites must be only just beyond the capability of the DIVM.
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How comes this launch is going on a baseline 401 yet the last launch was on an augmented Delta IV?
The Atlas V 401 has a better performance than the Delta IV Medium. For a GTO with delta-V to GSO = 1800 m/s:
AV 401: 4750 kg
DIVM: 4540 kg
DIVM+4/2: 6270 kg
So the performance required to lift the GPS IIF satellites must be only just beyond the capability of the DIVM.
Are more launches planned for the GPS network on the 401?
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I am confused about the SVN number for this GPS bird.
I have:
IIF Flight IIF SV GPS SV
1 1 62
2 2 63
4 3 66 <-- this flight
3 4 65
I would have expected IIF SV-3 to be GPS SV 64, and IIF SV-5 to be GPS SV 66.
The overall and subseries SV numbers ran in tandem in previous subseries.
Are we confident that this bird is IIF SV-3 and SVN 66?
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How comes this launch is going on a baseline 401 yet the last launch was on an augmented Delta IV?
The Atlas V 401 has a better performance than the Delta IV Medium. For a GTO with delta-V to GSO = 1800 m/s:
AV 401: 4750 kg
DIVM: 4540 kg
DIVM+4/2: 6270 kg
So the performance required to lift the GPS IIF satellites must be only just beyond the capability of the DIVM.
Are more launches planned for the GPS network on the 401?
According to the US launch schedule here, http://forum.nasaspaceflight.com/index.php?topic=8184.msg1052295;boardseen#new
I saw at least two next year
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From 8200 ft away and Iphone.
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From 8200 ft away and Iphone.
Could you feel the launch from there ? ;)
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From 8200 ft away and Iphone.
Nice!
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I am confused about the SVN number for this GPS bird.
I have:
IIF Flight IIF SV GPS SV
1 1 62
2 2 63
4 3 66 <-- this flight
3 4 65
I would have expected IIF SV-3 to be GPS SV 64, and IIF SV-5 to be GPS SV 66.
The overall and subseries SV numbers ran in tandem in previous subseries.
Are we confident that this bird is IIF SV-3 and SVN 66?
USAF are calling it SVN-66. It's not unheard of for SVNs to launch out of sequence.
http://www.afspc.af.mil/news/story.asp?id=123348442
I'm not sure about the SV designations; when I saw "GPS IIF SV-1" on the first launch I assumed it was just an alternative way of writing GPS IIF-1, and so I didn't keep track of them beyond that.
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I am confused about the SVN number for this GPS bird.
I have:
IIF Flight IIF SV GPS SV
1 1 62
2 2 63
4 3 66 <-- this flight
3 4 65
I would have expected IIF SV-3 to be GPS SV 64, and IIF SV-5 to be GPS SV 66.
The overall and subseries SV numbers ran in tandem in previous subseries.
Are we confident that this bird is IIF SV-3 and SVN 66?
USAF are calling it SVN-66. It's not unheard of for SVNs to launch out of sequence.
http://www.afspc.af.mil/news/story.asp?id=123348442
I'm not sure about the SV designations; when I saw "GPS IIF SV-1" on the first launch I assumed it was just an alternative way of writing GPS IIF-1, and so I didn't keep track of them beyond that.
Right, I agree that it is SVN-66 and Flight IIF-4 and that the SVNs don't get launched in flight order. It's the IIF SV number I am questioning - I suspect it's SV-5 and not SV-3 since the IIF SV and overall SVN should run in parallel, both represent production/manufacture order. But maybe there is some subtlety I don't understand. (F stands for flight, and SV stands for Space Vehicle).
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From 8200 ft away and Iphone.
Could you feel the launch from there ? ;)
One of the loudest.
I have seen Delta II from 1 mile, Shuttle from 3 and Titan III and Delta IV Heavy from 2.5
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I am confused about the SVN number for this GPS bird.
I have:
IIF Flight IIF SV GPS SV
1 1 62
2 2 63
4 3 66 <-- this flight
3 4 65
I would have expected IIF SV-3 to be GPS SV 64, and IIF SV-5 to be GPS SV 66.
The overall and subseries SV numbers ran in tandem in previous subseries.
Are we confident that this bird is IIF SV-3 and SVN 66?
USAF are calling it SVN-66. It's not unheard of for SVNs to launch out of sequence.
http://www.afspc.af.mil/news/story.asp?id=123348442
I'm not sure about the SV designations; when I saw "GPS IIF SV-1" on the first launch I assumed it was just an alternative way of writing GPS IIF-1, and so I didn't keep track of them beyond that.
Right, I agree that it is SVN-66 and Flight IIF-4 and that the SVNs don't get launched in flight order. It's the IIF SV number I am questioning - I suspect it's SV-5 and not SV-3 since the IIF SV and overall SVN should run in parallel, both represent production/manufacture order. But maybe there is some subtlety I don't understand. (F stands for flight, and SV stands for Space Vehicle).
Answered my own question: http://www.gpsworld.com/gps-block-iif-4-launch-set-may-15/ points me back to
http://www.spaceflightnow.com/atlas/av039/payload.html#.UZQSGeEcrR4
which says
the GPS 2F-4 mission, which is Boeing's Space Vehicle (SV) #5.
so that makes sense and SV #3 must still be on the ground.
It also says
Each SV is a named for a navigation star and its constellation. SV-5 is named Vega, with constellation Lyra
This is the first I've heard of individual names for the satellites - I assume it's just for the IIF satellites, do we have the list of names?
Who uses them - are they Boeing names or USAF names?
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USAF and they are on the patches
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From 8200 ft away and Iphone.
That's pretty good!
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USAF and they are on the patches
Thanks. I found IIF-2 = Sirius and IIF-3 = Arcturus but I can't find IIF-1
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From 8200 ft away and Iphone.
Very nice Jim!
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USAF and they are on the patches
now that becomes clear thx for the info.
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Oh, and I thought the webcast would have come back up.
But no, ULA say Spacecraft/Sep!
Oh well. Congrats to all involved!
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MECO-2 and spacecraft separation - congrats ULA
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Congrats to ULA. What a beautiful launch.
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Oh, and I thought the webcast would have come back up.
But no, ULA say Spacecraft/Sep!
Oh well. Congrats to all involved!
And here I am continually trying to connect...
Thanks, and congrats to ULA!
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Congrats to all the teams, well done! Flawless launch the ULA way... ;)
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Cape Canaveral Air Force Station, Fla. (May 15, 2013) – A United Launch Alliance Atlas V rocket blasts off from Space Launch Complex-41 carrying the fourth Global Positioning System (GPS) IIF-4 satellite for the U.S. Air Force at 5:38 p.m. EDT today from Space Launch Complex-41. This is the fourth ULA launch this year and marks the 70th launch success in the 77 months since ULA was formed. GPS IIF-4 is the fourth in a series of next generation GPS satellites and will join a worldwide timing and navigation system utilizing 24 satellites in six different planes, with a minimum of four satellites per plane positioned in orbit approximately 11,000 miles above the earths’ surface.
Photo by Pat Corkery, United Launch Alliance
United Launch Alliance Launches 70th Successful Mission in 77 Months with the Launch of the GPS IIF-4 Satellite for the Air Force
Cape Canaveral Air Force Station, Fla., (May 15, 2013) – A United Launch Alliance (ULA) Atlas V rocket successfully launched the fourth Global Positioning System (GPS) IIF-4 satellite for the U.S. Air Force at 5:38 p.m. EDT today from Space Launch Complex-41.
"The ULA team is honored to place another next-generation GPS satellite on orbit for our US Air Force customer,” said Jim Sponnick, ULA vice president, Mission Operations. “Today’s successful delivery of the GPS IIF-4 mission represents the 70th launch success in the 77 months since ULA was formed – an accomplishment made possible by seamless integration of the customer and industry team; reliable production and launch operation processes; and a one-launch-at-a-time focus on mission success for these critical space assets.”
This mission was launched aboard an Atlas V 401 Evolved Expendable Launch Vehicle (EELV), which includes a 4-meter diameter payload fairing. The booster for this mission was powered by the RD AMROSS RD-180 engine and the Centaur upper stage was powered by a single Pratt & Whitney Rocketdyne RL-10A engine.
“The ULA team has launched 51 GPS missions on Delta II and Delta IV vehicles and this mission marks the first operational GPS mission launched on an Atlas V launch vehicle,” said Sponnick. “Successfully and efficiently integrating and launching these satellites on both EELV launch systems provides operational flexibility and in the future, capabilities such as dual launch will provide even greater flexibility and also enable lower launch costs for our customers.”
GPS IIF-4 is the fourth in a series of next generation GPS satellites and will join a worldwide timing and navigation system utilizing 24 satellites in six different planes, with a minimum of four satellites per plane positioned in orbit approximately 11,000 miles above the earths’ surface. The GPS IIF series provides improved accuracy and enhanced performance for GPS users.
The EELV program was established by the United States Air Force to provide assured access to space for Department of Defense and other government payloads. The commercially developed EELV Program supports the full range of government mission requirements, while delivering on schedule and providing significant cost savings over the heritage launch systems.
ULA program management, engineering, test, and mission support functions are headquartered in Denver, Colo. Manufacturing, assembly and integration operations are located at Decatur, Ala., and Harlingen, Texas. Launch operations are located at Cape Canaveral AFS, Fla., and Vandenberg AFB, Calif.
For more information on ULA, visit the ULA Web site at www.ulalaunch.com, or call the ULA Launch Hotline at 1-877-ULA-4321 (852-4321). Join the conversation at www.facebook.com/ulalaunch and twitter.com/ulalaunch.
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And the final revision of William's article now the mission has been completed from the LV side.
http://www.nasaspaceflight.com/2013/05/ula-atlas-v-launch-new-gps-satellite/
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Congrats to ULA!
http://www.youtube.com/watch?v=KlK2xtoxZsI
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Now this is some fast editing :)
http://www.youtube.com/watch?v=HyKnLMQC_Qk
Love the tune, very funky. I'm fits in with the Kenny Chesney I'm listening to right now.
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Objects now cataloged:
39166 23A 20449 x 20471 km x 55.0 deg - must be the GPS
39167 23B 20457 x 22342 km x 55.6 deg - must be the Centaur after depletion, so a modest orbit change only
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ATK Composite and Propulsion Technologies Help Launch GPS IIF-4 Satellite
ATK Supports the Launch of United Launch Alliance's Atlas V
ARLINGTON, Va., May 15, 2013 /PRNewswire/ -- ATK (NYSE: ATK) provided critical hardware for the United Launch Alliance (ULA) Atlas V that launched the U.S. Air Force's Global Positioning System (GPS) IIF-4 satellite today from Cape Canaveral Air Force Station, Fla.
GPS IIF-4 is the fourth satellite delivered by prime contractor Boeing as part of the GPS IIF contract for 12 next-generation GPS space vehicles. GPS IIF satellites continue to modernize the GPS constellation while providing positioning, navigation and timing services to civil and military users worldwide.
"ATK is proud to provide technologies that enabled the launch of the GPS IIF-4 satellite, which will bring enhanced capabilities to our soldiers and allies as well as civil users," said Blake Larson, president of ATK Aerospace Group. "Our support to this mission comes from all corners of ATK and highlights the broad cooperation we have with ULA."
For the ULA Atlas V rocket, ATK produced the 10-foot diameter composite heat shield, which provides essential protection for the first stage of the launch vehicle. The assembly was fabricated using advanced fiber placement manufacturing techniques at ATK's Iuka, Miss., facility. This is the 38th Atlas V launch using ATK-built composite structures.
The Atlas V rocket flew in the 401 vehicle configuration with a four-meter fairing and a single-engine Centaur upper stage. ATK manufactured the Reaction Control System propellant tank for the Atlas V at its Commerce, Calif., facility.
ATK also recently completed qualification of a new retrorocket, and eight of those solid motors supported separation of the spent first stage. The Atlas retrorocket is built at ATK's Elkton, Md., facility.
The Block IIF series will replace the GPS Block IIA satellites that were launched between 1990 and 1997. The IIF space vehicles provide improved accuracy, enhanced internal atomic clocks, better anti-jam resistance, a civil signal for commercial aviation and a longer design life.
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I am confused about the SVN number for this GPS bird.
I have:
IIF Flight IIF SV GPS SV
1 1 62
2 2 63
4 3 66 <-- this flight
3 4 65
I would have expected IIF SV-3 to be GPS SV 64, and IIF SV-5 to be GPS SV 66.
The overall and subseries SV numbers ran in tandem in previous subseries.
Are we confident that this bird is IIF SV-3 and SVN 66?
Previous flight, IIF-3, was SVN-65. I recall reading somewhere that SVN-64 got delayed in processing, but I don't have a link handy and my google-fu is failing.
-Bob
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Do we know what satellite it will replace? There are quite a few GPS satellites working well beyond their lifetimes by now....
It's being launched into SVN33 / SVN36 orbital slot, those two are very old but far from dead. Likely SVN33 will be paired up with SVN53 and SVN36 with SVN57. The constellation is working with 4 birds over stated requirement (31 vs 27) so they keep moving the older birds around until they start misbehaving seriously and get retired.
Every new launch needs to balance keeping the 24+3 layout while preparing for the next signal event, which now is M-Code / L2C Initial Operations Capability - each orbit with its 3 primary slots with a IIR-M or IIF bird, so those signals can be used without redundancy for basic 3D fixes.
Current status for L2C IOC, including IIF-4:
Orbit A - done
Orbit B - need one more
Orbit C - done
Orbit D - need two more
Orbit E - need two more
Orbit F - need two more
This creates an interesting conundrum, what if the old birds on orbits D,E and F are still fine, the the two IIA birds on orbit A die, each orbit is required to have their 3 primary slots filled plus one backup slot, but it would be down to 3 birds. It might also be possible to bring a retired 'residual' bird back to life, but it was put in residual status because it wasn't keeping up, so it's likely even worse now.
One way that would break the current geometry would be to fill neighboring orbits east and west with 6 birds total and leave the orbits which are ready for IOC with just 3 birds, breaking not only with the 24+3 layout, but with the basic 24 bird layout as well !
After SVN35 was retired, the two worst performing birds left in the constellation are PRN8/SVN38 and PRN9/SVN39 on plane A, but that plane is ready for the upcoming IOC, and they are in a triplet spot with PRN7/SVN48, so they are likely to simply be kept where they are until one die and the other is expected to die inside a year.
What makes 2nd SOPS job easier is birds are being retired due to bad performance, not because they actually died in duty, and bad performance can be detected at least an year ahead.
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GPS System Improved as New Boeing Satellite Enters Service
GPS IIF delivers better position, navigation and timing data
EL SEGUNDO, Calif., July 9, 2013 – The Global Positioning System, which millions of people use every day for precise navigation and timing, recently became more accurate and reliable as the fourth Boeing [NYSE: BA] GPS IIF satellite began operating in the U.S. Air Force network.
Launched May 15, that satellite was handed over to the Air Force after 19 days of post-launch validation to stabilize the vehicle and activate the navigation payload, and set healthy on June 21.
“With each IIF that we add to the network, the Air Force and Boeing give military and civilian users around the world better GPS navigation and timing information,” said Craig Cooning, Boeing vice president and general manager of Space & Intelligence Systems.
SVN-66, the official name of the new satellite, is now part of the active 31-satellite network. The next GPS IIF, the fifth of 12 planned, is slated for launch in October.
The new satellite replaces an earlier Boeing-built model launched in 1996.