Author Topic: SpaceX Falcon 9 - NROL-76 - May 1, 2017 - DISCUSSION  (Read 219925 times)

Online abaddon

  • Full Member
  • ****
  • Posts: 1443
  • Liked: 888
  • Likes Given: 704
Re: SpaceX Falcon 9 - NROL-76 - May 1, 2017 - DISCUSSION
« Reply #260 on: 04/28/2017 09:01 PM »
Haven't seen anyone on this thread suggesting NRO-76 needs upgraded thrust.  But the point of the RS-68As for NRO-15 proves that the NRO is not adverse to flying on the first mission using upgraded engines/thrust.
The point of the RS-68A is the NRO paid for that development specifically for NRO-15 and subsequent payloads.  They could not fly on Delta IV Heavy without the RS-68A upgrade.  So sure, the NRO isn't adverse to flying on the first mission using upgraded engines/thrust, when the payload couldn't fly on anything else.  That doesn't prove the NRO isn't adverse to flying on the first mission using upgraded engines/thrust, when there is absolutely no need for that.  In other words, using the RS-68A as a point of comparison is not valid.
« Last Edit: 04/28/2017 09:01 PM by abaddon »

Offline LouScheffer

  • Full Member
  • ****
  • Posts: 1533
  • Liked: 1682
  • Likes Given: 195
Re: SpaceX Falcon 9 - NROL-76 - May 1, 2017 - DISCUSSION
« Reply #261 on: 04/28/2017 09:47 PM »
I'm not sure what to think.  The Orbcomm OG2 flight featured RTLS and its first stage burned for 2 minutes 20 seconds (according to the press kit).   The deployed payloads only weighed about 1.9 tonnes, but the orbit was higher than Dragon insertions (620 x 660 km x 47 deg). 

The CRS RTLS missions saw the first stage burn for 2 min 21 sec with a probably 9-ish tonne payload.  Those insertion orbits are typicaly 200 x 360 km  x 51.6 deg.   So, not much of a burn time difference despite the payload mass difference. 

Now we have NROL 76 with a shortest-ever 2 min 17 sec burn.

I'm not prophet, but that seems to suggest uprated engines. They're dumping fuel a lot faster.
I think upgraded engines - nothing else make engineering sense.  You don't want to land with more fuel - it puts more stress on the gear, it's more to remove, it takes longer for the LOX to boil off, etc.  You don't want a longer boostback burn, or you'll overshoot and/or go higher, which you don't want.  A longer entry burn makes little sense as well - especially 12 seconds longer which you would need to burn the extra fuel.  And if the other burns are not longer, the only two possibilities are a partial fuel load, or faster consumption.  .A partial fuel load would screw up procedures and modelling, and leave less margin for engine out or other problems.

So the only sensible reason I can see is faster consumption, meaning uprated engines.

Re: SpaceX Falcon 9 - NROL-76 - May 1, 2017 - DISCUSSION
« Reply #262 on: 04/28/2017 09:54 PM »
Looks like Go Quest is leaving the port: https://www.vesselfinder.com/?imo=1155515

Fairing recovery is a go?

Offline mn

  • Full Member
  • **
  • Posts: 200
  • United States
  • Liked: 93
  • Likes Given: 31
Re: SpaceX Falcon 9 - NROL-76 - May 1, 2017 - DISCUSSION
« Reply #263 on: 04/28/2017 10:55 PM »
Just because they NEEDED the uprated performance doesn't mean they HAD to be FIRST to use it.

Edit: In the case of the RS68A not being first could have meant a long wait, that is certainly not the case here.
« Last Edit: 04/28/2017 11:26 PM by mn »

Online macpacheco

  • Full Member
  • ****
  • Posts: 804
  • Vitoria-ES-Brazil
  • Liked: 315
  • Likes Given: 2329
Re: SpaceX Falcon 9 - NROL-76 - May 1, 2017 - DISCUSSION
« Reply #264 on: 04/29/2017 12:17 AM »
There's also the possibility that F9 Block IV has some mods required by NRO, but the launch doesn't need the extra performance. For all we know, the engine hasn't changed at all for higher thrust, but there are other changes.
It could be the first Block IV launch, but running the engine with Block III limits.
Its also possible the NRO requested SpaceX fly a Block IV on a prior launch but do so 100% silently.
That's the unfortunate world of maximum secrecy that drives us fans MAD !
Looking for companies doing great things for much more than money

Offline envy887

  • Senior Member
  • *****
  • Posts: 2581
  • Liked: 1161
  • Likes Given: 731
Re: SpaceX Falcon 9 - NROL-76 - May 1, 2017 - DISCUSSION
« Reply #265 on: 04/29/2017 12:36 AM »
There's also the possibility that F9 Block IV has some mods required by NRO, but the launch doesn't need the extra performance. For all we know, the engine hasn't changed at all for higher thrust, but there are other changes.
It could be the first Block IV launch, but running the engine with Block III limits.
Its also possible the NRO requested SpaceX fly a Block IV on a prior launch but do so 100% silently.
That's the unfortunate world of maximum secrecy that drives us fans MAD !

None of this corresponds with MECO being earlier. If they are running at Block 3 thrust, why is MECO earlier?

If Block 4 has a thrust upgrade, then flying without the thrust upgrade isn't actually flying Block 4, so what's the point?

Offline Galactic Penguin SST

Re: SpaceX Falcon 9 - NROL-76 - May 1, 2017 - DISCUSSION
« Reply #266 on: 04/29/2017 01:13 AM »
Only just tweeted but presumably from earlier this week?

Quote
#NROL76 will carry a classified payload designed, built and operated by @NatReconOfc. @SpaceX @45thSpaceWing

https://twitter.com/natreconofc/status/858007929252974592

Is this the first time the NRO logo can be spotted on any rocket since the declassification of its existence in the 1990s? I certainly can't think of any previous launch where the organization logo is used instead of the mission logo (which first started around the millennium IIRC).
Chinese spaceflight is a cosmic riddle wrapped in a galactic mystery inside an orbital enigma... - (not) Winston Churchill

Offline iamlucky13

  • Full Member
  • ****
  • Posts: 1660
  • Liked: 102
  • Likes Given: 92
Re: SpaceX Falcon 9 - NROL-76 - May 1, 2017 - DISCUSSION
« Reply #267 on: 04/29/2017 01:30 AM »
Would they be using it for polar sub comms?

That seems like reasonable speculation. High dwell time over the poles could aid with that, among other things.

But general sigint over the poles is at least as compelling of a purpose.

Offline Kabloona

  • Senior Member
  • *****
  • Posts: 4025
  • Velocitas Eradico
  • Fortress of Solitude
  • Liked: 2203
  • Likes Given: 445
Re: SpaceX Falcon 9 - NROL-76 - May 1, 2017 - DISCUSSION
« Reply #268 on: 04/29/2017 03:19 AM »
Looks like Go Quest is leaving the port: https://www.vesselfinder.com/?imo=1155515

Fairing recovery is a go?

That was apparently a short round trip down the channel.. She's back in port now.

GO Searcher has been the fairing chase ship on previous missions.

Offline Kabloona

  • Senior Member
  • *****
  • Posts: 4025
  • Velocitas Eradico
  • Fortress of Solitude
  • Liked: 2203
  • Likes Given: 445
Re: SpaceX Falcon 9 - NROL-76 - May 1, 2017 - DISCUSSION
« Reply #269 on: 04/29/2017 03:26 AM »
Would they be using it for polar sub comms?

That seems like reasonable speculation. High dwell time over the poles could aid with that, among other things.

But general sigint over the poles is at least as compelling of a purpose.

The two implements on the patch seem significant. In the foreground is the spyglass, meaning "we're watching you." In the background is the gun, not drawing a bead, but ready if needed. Both messages meant for our friend, Boris the polar Bear, as he sniffs around the arctic?
« Last Edit: 04/29/2017 03:39 AM by Kabloona »

Offline satwatcher

  • Member
  • Posts: 99
  • Liked: 45
  • Likes Given: 41
Re: SpaceX Falcon 9 - NROL-76 - May 1, 2017 - DISCUSSION
« Reply #270 on: 04/29/2017 08:07 AM »
Now we have NROL 76 with a shortest-ever 2 min 17 sec burn.

Don't forget that main engine cut-off could be early because more fuel is required for the boost-back, reentry and landing burns.

Offline Star One

  • Senior Member
  • *****
  • Posts: 8018
  • UK
  • Liked: 1281
  • Likes Given: 168
Re: SpaceX Falcon 9 - NROL-76 - May 1, 2017 - DISCUSSION
« Reply #271 on: 04/29/2017 08:47 AM »
Would they be using it for polar sub comms?

That seems like reasonable speculation. High dwell time over the poles could aid with that, among other things.

But general sigint over the poles is at least as compelling of a purpose.

It's more likely it's because the KH-11s require that because of their orbits.

Would they be using it for polar sub comms?

That seems like reasonable speculation. High dwell time over the poles could aid with that, among other things.

But general sigint over the poles is at least as compelling of a purpose.

The two implements on the patch seem significant. In the foreground is the spyglass, meaning "we're watching you." In the background is the gun, not drawing a bead, but ready if needed. Both messages meant for our friend, Boris the polar Bear, as he sniffs around the arctic?

The spyglass is probably a reference to the KH-11. Between the KH-11 & commercial imagery that they buy in they do not need any other kind of optical reconnaissance assets.
« Last Edit: 04/29/2017 08:50 AM by Star One »

Online Ronsmytheiii

  • Moderator
  • Global Moderator
  • Senior Member
  • *****
  • Posts: 22307
  • Liked: 580
  • Likes Given: 239
Re: SpaceX Falcon 9 - NROL-76 - May 1, 2017 - DISCUSSION
« Reply #272 on: 04/29/2017 09:20 AM »
Haven't seen anyone on this thread suggesting NRO-76 needs upgraded thrust.  But the point of the RS-68As for NRO-15 proves that the NRO is not adverse to flying on the first mission using upgraded engines/thrust.

From what I understand Jim has said in the past, DoD isn't adverse to flying on the first flight or upgrade as long as the vendor gives them extensive access during the development. SpaceX doesn't seem to like this approach, so DoD came up with the flight certification program to overcome the lack of development insight.
"Every vision is a joke until the first man accomplishes it; once realized, it becomes commonplace." - Robert Goddard

Offline William Graham

  • Senior Member
  • *****
  • Posts: 4049
  • Liked: 79
  • Likes Given: 50
Re: SpaceX Falcon 9 - NROL-76 - May 1, 2017 - DISCUSSION
« Reply #273 on: 04/29/2017 10:13 AM »
Only just tweeted but presumably from earlier this week?

Quote
#NROL76 will carry a classified payload designed, built and operated by @NatReconOfc. @SpaceX @45thSpaceWing

https://twitter.com/natreconofc/status/858007929252974592

Well, so much for it being a BSS702. I think this is looking more and more like a technology demonstrator bound for LEO.

Offline Alter Sachse

  • Full Member
  • ****
  • Posts: 424
  • Germany (near Heidelberg)
  • Liked: 63
  • Likes Given: 101
Re: SpaceX Falcon 9 - NROL-76 - May 1, 2017 - DISCUSSION
« Reply #274 on: 04/29/2017 11:19 AM »
Only just tweeted but presumably from earlier this week?

Quote
#NROL76 will carry a classified payload designed, built and operated by @NatReconOfc. @SpaceX @45thSpaceWing

https://twitter.com/natreconofc/status/858007929252974592

Well, so much for it being a BSS702. I think this is looking more and more like a technology demonstrator bound for LEO.
reply #40 11/04/2016
Or could it be a satellite to test new technology ?
That was also my guess
« Last Edit: 04/29/2017 11:33 AM by Alter Sachse »

Online mikes

  • Full Member
  • ***
  • Posts: 326
  • Norwich, UK
  • Liked: 66
  • Likes Given: 42
Re: SpaceX Falcon 9 - NROL-76 - May 1, 2017 - DISCUSSION
« Reply #275 on: 04/29/2017 11:48 AM »
Fairing recovery is a go?

Do we know that fairing recovery is on this flight?

I would expect SpaceX to want video documentation of the whole process, but NRO are strongly averse to cameras near their birds.

Offline Jcc

  • Full Member
  • ****
  • Posts: 795
  • Liked: 169
  • Likes Given: 68
Re: SpaceX Falcon 9 - NROL-76 - May 1, 2017 - DISCUSSION
« Reply #276 on: 04/29/2017 12:00 PM »
Now we have NROL 76 with a shortest-ever 2 min 17 sec burn.

Don't forget that main engine cut-off could be early because more fuel is required for the boost-back, reentry and landing burns.

More fuel compared to what? This is a shorter S1 burn than other boost back missions, which were all successful, so why would they choose to reserve more fuel? More likely, increased thrust means the existing fuel finishes sooner, and if they are less far down range, they actually need less fuel for boost back.

Online hopalong

  • Member
  • Posts: 71
  • Milton Keynes
  • Liked: 19
  • Likes Given: 18
Re: SpaceX Falcon 9 - NROL-76 - May 1, 2017 - DISCUSSION
« Reply #277 on: 04/29/2017 12:51 PM »
Fairing recovery is a go?

Do we know that fairing recovery is on this flight?

I would expect SpaceX to want video documentation of the whole process, but NRO are strongly averse to cameras near their birds.

My thoughts as well, I would not be surprised if the normal upward looking camera which records the fairings separation as been removed at NRO's request. SpaceX may try for recovery, but no cameras which could catch slight of the payload as the fairings separate .

Offline vanoord

  • Full Member
  • ****
  • Posts: 454
  • Liked: 275
  • Likes Given: 31
Re: SpaceX Falcon 9 - NROL-76 - May 1, 2017 - DISCUSSION
« Reply #278 on: 04/29/2017 01:10 PM »
Go Quest and Go Searcher are still in port.

Getting to the point where they'd be cutting it fine to get out to the potential recovery area in time.

Offline Norm38

  • Full Member
  • ****
  • Posts: 968
  • Liked: 368
  • Likes Given: 492
Re: SpaceX Falcon 9 - NROL-76 - May 1, 2017 - DISCUSSION
« Reply #279 on: 04/29/2017 01:54 PM »
I thought for this mission they might send OCISLY out with the bouncy castle. Unless it's getting maintenance, why not?

Tags: