Author Topic: LIVE: SpaceX - Falcon I (Mk.II) NET March 20 (Attempt 2) (Read 265152 times)

landofgrey · « **Reply #360 on:** 03/21/2007 01:13 am »

Buliding rockets is still hard. People think it's gotten easier in 50 years but it hasn't. Failures should be EXPECTED and aren't really failures at all for a development/test vehicle. They are learing opportunities to better refine and perfect the rocket. Every launch vehicle has had its share of lessons; this is no different.

I actually went outside (Florida) to see if I could spot anything re-entering. Of course I didn't, but I couldn't resist.

JonSBerndt · « **Reply #361 on:** 03/21/2007 01:14 am »

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Wildthing - 20/3/2007 9:06 PM

What are the possible reasons for the 1st stage impacting the second on seperation ??...misalignment of the stages ??....and is there any word on the recovery of the 1st stage ...was that planned for this flight ??

Ideally, you would null out rates and hold attitude prior to staging. If there was a small rate at sep, the upper part of the lower half and the lower part of the upper half are moving "in a bad way", towards recontact. I think some rockets separate in a two step process at the plane of the nozzle exit (avoiding recontact) and then an "adapter" is jettisoned after ignition (because then the rocket has a means of being controlled - we are assuming that there is no pitch/yaw control unless powered).

Jon

nacnud · « **Reply #362 on:** 03/21/2007 01:14 am »

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JesseD - 21/3/2007 3:11 AM

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nacnud - 20/3/2007 10:08 PM

Atlantic? That can't be right not after only 2 mins of powered flight.

My replay shows at least 5:00 of powered flight , +/- 5sec, before the roll moment started increasing exponentially and the 2nd stage started veering off course.

Sorry I should have been clearer, I was talking about the 1st stage. I've edited the post for clarity.

nathan.moeller · « **Reply #363 on:** 03/21/2007 01:14 am »

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harryw - 20/3/2007 9:13 PM

I have now sat through hours and hours to watch 2 launches in which SpaceX dropped the video the second things went bad. Won't make that mistake anymore...

When the rocket cam fails there's nothing to see. They didn't drop the feed. They lost the signal.

Jeff Bingham · « **Reply #364 on:** 03/21/2007 01:15 am »

I had only assumed there was a deliverable payload, but hadn't actually seen the media kit or other info....either way, it was a demonstration flight and anyone willing to provide a payload would understand the risks, so I think Elon's characterization of it being a "good day for SpaceX" is justified...and it's a good day for private/entrepreneurial spaceflight in general on the same basis.

DaveS · « **Reply #365 on:** 03/21/2007 01:15 am »

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pmoon - 21/3/2007 3:13 AM

Any clue where the second stage should be reentering and if it would be visible?

It will only be visible if you live along the equator. So not much chance of seeing if you live in the US or Europe.

braddock · « **Reply #366 on:** 03/21/2007 01:16 am »

Question on potential causes of the roll issue:

"Could be a helium leak. We have a cold gas roll control system, could be a problem with one of the roll control jets. But it is easy to come up with something that could be false without additional information."

"Certainly if it is a leak issue, we can make sure that any potential leaks are addressed in spades. If it is a cold jet issue, that would be very easy to address as well."

landofgrey · « **Reply #367 on:** 03/21/2007 01:16 am »

I haven't looked at the video again yet, but it did seem to me that burnout/sep/ignition happened pretty quickly in sequence. Harder to null everything without enough of a delay.

Chris Bergin · « **Reply #368 on:** 03/21/2007 01:16 am »

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zerm - 21/3/2007 2:09 AM

I LOVE L2!! Just a few minutes after the launch and here I sit reviewing the video on my computer! Thanks skinny and thanks Chris for L2!
BTW- that almost looks like propellant sloshing to my untrained eye- it'll be intresting to see what they find.

Thanks, and -
Really was moving around near the end!

Andrewwski · « **Reply #369 on:** 03/21/2007 01:16 am »

Yes...at least they didn't do what Sea Launch did.

Not that the problem was quite as bad, but there's a difference between no signal and intentional pulling

Eeyore3061 · « **Reply #370 on:** 03/21/2007 01:18 am »

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Wildthing - 20/3/2007 10:06 PM

What are the possible reasons for the 1st stage impacting the second on seperation ??...misalignment of the stages ??....and is there any word on the recovery of the 1st stage ...was that planned for this flight ??

One possable reason, off the top of my head, is that that InterStage is packed so tight. In fact, IIRC, the parachutes are stored on top of the 1st stage in such a way that the 2nd stage engine bell covers them.

If, and I really do mean *if*, the staging bump was contributer to the 2nd stage underperformace then it may go down as a design flaw due to the lack of room there is to extract the 2nd stage engine bell. :frown:

Michael

braddock · « **Reply #371 on:** 03/21/2007 01:19 am »

"I think it is fair to characterize this as a success, and a good day. Not a perfect day, but a good day."

Norm Hartnett · « **Reply #372 on:** 03/21/2007 01:20 am »

Firstly a well done to SpaceX and all the folks that have worked so hard over the last few years.

Secondly I am appalled at the virulent nature of some of the comments I’ve seen here. What is the affiliation of these people, NASA, LockMart, USA? Whatever it is I have rarely seen such sour grapes. If any of you could do half as well with twice the budget we would be a lot further into the VSE.

Truly a great accomplishment that ranks with SpaceShip One and Genesis I in the alt.space endeavors.

braddock · « **Reply #373 on:** 03/21/2007 01:20 am »

"We will post an update within an hour."

Jeff Lerner · « **Reply #374 on:** 03/21/2007 01:21 am »

...which is an interesting point in that what appears to be a successful 1st stage operation, may indeed have some sort of a major design defect affecting proper stage seperation...

JonSBerndt · « **Reply #375 on:** 03/21/2007 01:22 am »

Definitely does look like there was recontact - I agree.

Jon

William Graham · « **Reply #376 on:** 03/21/2007 01:22 am »

Will there be a free version of the video for this launch?

reubenb · « **Reply #377 on:** 03/21/2007 01:22 am »

Any word on getting a video with the sound of the launch? That would greatly increase the awesomeness factor

Danderman · « **Reply #378 on:** 03/21/2007 01:23 am »

It was a great job getting the vehicle to 300 km, but a control system failure in the second stage is not a good thing. Presumably, the control system would be used in the Falcon 9 upper stage, as well, so this problem has to be resolved for both vehicles. If there were not parachutes below the second stage engine, firing in the hole would be a way to avoid impingement by the dropping first stage. But we still don't know if there was a strike, or if the misalignment of the first stage while dropping was the problem OR if the control system failure (if that is what the problem was) was caused by something else. At any rate, after over a minute of flight, any problems at staging should have been damped out, and that is again an indicator of something seriously wrong with the control system.

My guess is that SpaceX will not fly again for many months.

Jim · « **Reply #379 on:** 03/21/2007 01:23 am »

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Norm Hartnett - 20/3/2007 10:20 PM

Firstly a well done to SpaceX and all the folks that have worked so hard over the last few years.

Secondly I am appalled at the virulent nature of some of the comments I’ve seen here. What is the affiliation of these people, NASA, LockMart, USA? Whatever it is I have rarely seen such sour grapes. If any of you could half as well with twice the budget we would be a lot further into the VSE.

Truly a great accomplishment that ranks with SpaceShip One and Genesis I in the alt.space endeavors.

Not really. Elon is full of hubris and needs to talk less and do more. No matter what they say, the mission was a failure. And repeatibility of the first part of the flight is not guaranteed