First time I recall seeing a close-up of the Falcon 9 on the launch pad showing how the rocket is supported. I had a very different mental image.
They've designed an interesting holddown/release system, and it appears to be overengineered by a large factor.
Also, it looks like the outer (corner) engines are angled away for ignition.
Quote from: MKremer on 03/10/2010 07:27 amThey've designed an interesting holddown/release system, and it appears to be overengineered by a large factor. Not necessarily overengineered if you take into account F9 is supposed to have a fairly high T/W ratio, higher than either EELV w/no SRBs.
Quote from: MKremer on 03/10/2010 07:27 amAlso, it looks like the outer (corner) engines are angled away for ignition.Yep, looks that way to me, too. Guess that'll be another thing in which F9 is similar to a Zenit. Cosine losses, but better control if unexpected engine shutdowns happen. Or expected ones at MECO-17 s.
Does not mean it will be this way through out powered flight. Once they are clear of the pad and have more room to move, they "could" undo the angle and reduce Cosine losses.
Video of abort recorded from SFN live stream:
Quote from: kevin-rf on 03/10/2010 12:31 pmDoes not mean it will be this way through out powered flight. Once they are clear of the pad and have more room to move, they "could" undo the angle and reduce Cosine losses. That would be atypical for launchers. Normally, they toe out after clearing the pad to reduce flame damage on the pad and maybe get out of there a bit quicker. Zenit does it from what I can see. Delta IV SRMs also. I'm not sure what would be gained the other way around.
Quote from: Damon Hill on 03/10/2010 05:21 amFirst time I recall seeing a close-up of the Falcon 9 on the launch pad showing how the rocket is supported. I had a very different mental image.Shown in action here: http://spacex.com/assets/video/20100104_11f9release.wmv
I could see a company party with everyone pitching in to manually push it to the pad...(in railroad parlance, the Armstrong method)
FWIW, @jeff_foust cites Larry Williams as saying "spin start" abort during F9 test firing happens frequently in tests in Texas; "not a big issue".Not a thing you'd want happening regularly on an operational vehicle, though.