Author Topic: SpaceX Falcon Heavy Discussion (Thread 2)  (Read 179872 times)

Online ugordan

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Re: SpaceX Falcon Heavy Discussion (Thread 2)
« Reply #480 on: 02/10/2015 09:01 AM »
Not sure if you're arguing or agreeing with what I said. Yes, the whole rocket seems to be rotated 180 deg at certain times, but that's quite likely a snafu (a.k.a. "artistic license"), but one core is always rotated with respect to the other two.

It's also likely artistic license that the vehicle is shown flying with the booster plane aligned with the horizon, F9 guidance doesn't really care about the vehicle roll state.

Offline ChrisWilson68

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Re: SpaceX Falcon Heavy Discussion (Thread 2)
« Reply #481 on: 02/10/2015 09:19 AM »
It's also likely artistic license that the vehicle is shown flying with the booster plane aligned with the horizon, F9 guidance doesn't really care about the vehicle roll state.

Of course F9 guidance cares about vehicle roll state.  Watch any video of a Falcon 9 launch and see if the vehicle is rolling.  It isn't.  That doesn't happen by accident.

Online ugordan

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Re: SpaceX Falcon Heavy Discussion (Thread 2)
« Reply #482 on: 02/10/2015 09:26 AM »
Sigh.  I said roll state, not roll rate. The vehicle guidance doesn't use a roll program like older LVs did, it uses a combined pitch/yaw program. Watch the 1st F9 launch and tell me if you see the vehicle rolling *back* to the pre-liftoff roll orientation or just nulling it and keeping going. Watch any of the subsequent launches and tell me if you see any roll maneuver done post liftoff.

Online Chris Bergin

Re: SpaceX Falcon Heavy Discussion (Thread 2)
« Reply #483 on: 02/10/2015 11:37 AM »
So some folk who use NSF and Reddit have been asking me about this rumor:
http://www.reddit.com/r/spacex/comments/2vbre1/falcon_heavy_hits_overpass_during_transport/

So I asked around and I'm told there was an incident. Very minor, however.

I've got another Falcon Heavy update article in draft, covering early FH flow, more 39A mod updates and some additional swooning/analysis over that epic video they published, so I'll ask them if they want to provide an official quote on it when I ask them for a final status update ahead of publication.

Offline deruch

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Re: SpaceX Falcon Heavy Discussion (Thread 2)
« Reply #484 on: 02/10/2015 11:40 PM »
Not sure if you're arguing or agreeing with what I said. Yes, the whole rocket seems to be rotated 180 deg at certain times, but that's quite likely a snafu (a.k.a. "artistic license"), but one core is always rotated with respect to the other two.

If the above is replying to me, I was posting a capture of a frame to point out what you were talking about.  It is very noticeable that the boosters are rotated 180o to each other (once you look for it anyways!).  It is maintained throughout the entire clip. 
Shouldn't reality posts be in "Advanced concepts"?  --Nomadd

Online Chris Bergin

Re: SpaceX Falcon Heavy Discussion (Thread 2)
« Reply #485 on: 02/16/2015 12:17 PM »
Let's give this 100,000 view thread a new thread while we're housekeeping. New article in draft, just waiting for some responses back before it goes on in the coming days.

Link:
http://forum.nasaspaceflight.com/index.php?topic=36806.0

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