Author Topic: Falcon 1 - Post Failure thread (Read 134934 times)

Tap-Sa · « **Reply #40 on:** 03/24/2006 11:48 pm »

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amon - 25/3/2006 2:44 AM
Ice perhaps?

Probably, around second stage LOX tank. It had no blanket around it.

blueguitarbob · « **Reply #41 on:** 03/24/2006 11:51 pm »

I wonder if SpaceX people tested the blanket removal with filled LOX tank?

They just did.

I've used velco in some industrial designs before, and its amazingly complex to predict its attachment/detachment. We abandoned it as a fastener, because it was unpredictable. Dang stuff would hold like cement sometimes, then fall off in a stiff breeze the next. I'm sure they'll fix it...

NASA_Twix_JSC · « **Reply #42 on:** 03/24/2006 11:58 pm »

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Delta Manager - 24/3/2006 6:41 PM

They'll learn. They may need to learn this again before they think they can join the big league.

And you're in the big league, yes, we know

newsartist · « **Reply #43 on:** 03/24/2006 11:59 pm »

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TimR - 24/3/2006 7:41 PMI just don't see what a blanket could do to a rocket engine, but I guess anything is possible.

If it disturbed the expected airflow, that could have allowed heat recirculation onto the aft end, and burned something critical.

One, (or more, it was a long time ago,) of the prototype Atlas-As failed, and it was found that the turbopump exhaust was being sucked into the vitals. A simple addition to take the exhaust outboard solved it.

Tony T. Harris · « **Reply #44 on:** 03/25/2006 12:00 am »

I believe the blanket could easily changed the way the airflow distributed. Do we have a video of the vehicle's acsent from a land based camera tracking?

nacnud · « **Reply #45 on:** 03/25/2006 12:01 am »

After reading the futron study velcro blankets sound like a bad idea, I don't expect to see them again.

James Lowe1 · « **Reply #46 on:** 03/25/2006 12:02 am »

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Tony T. Harris - 24/3/2006 7:00 PM

I believe the blanket could easily changed the way the airflow distributed. Do we have a video of the vehicle's acsent from a land based camera tracking?

I don't think there was one!

Propforce · « **Reply #47 on:** 03/25/2006 12:03 am »

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DaveS - 24/3/2006 3:57 PM

Seeing that last image from the aft-looking camera, my bets are on a burn-through of either the Merlin nozzle or the structure.

Sure looks like it. The exhaust went from a pretty steady white steam to a flash then yellow flame flapping in the breeze.

My guess is there was a "breach" in the combustion chamber.

DaveS · « **Reply #48 on:** 03/25/2006 12:05 am »

I guess that best view of the failure would have been from the Recovery Vessel.

Tap-Sa · « **Reply #49 on:** 03/25/2006 12:11 am »

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Propforce - 25/3/2006 3:03 AM

My guess is there was a "breach" in the combustion chamber.

My guess is there was no failure in the engine, the visible effects were part of thrust termination sequence. RSO hit the button because vehicle veered off course, or just because it was clear that the blanket didn't come off as it was supposed to, which was in violation of flight specs.

NASA_LaRC_SP · « **Reply #50 on:** 03/25/2006 12:12 am »

You can hear the RSO making the call. It's garballed, but I'm pretty sure that he was confirming his decision.

amon · « **Reply #51 on:** 03/25/2006 12:13 am »

Notice that there is no sign or roll in the last frames. The water/horizon line stays constant.

hyper_snyper · « **Reply #52 on:** 03/25/2006 12:16 am »

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Tap-Sa - 24/3/2006 8:11 PM
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Propforce - 25/3/2006 3:03 AM My guess is there was a "breach" in the combustion chamber.
My guess is there was no failure in the engine, the visible effects were part of thrust termination sequence. RSO hit the button because vehicle veered off course, or just because it was clear that the blanket didn't come off as it was supposed to, which was in violation of flight specs.

I don't understand. The termination sequence forces the Merlin to divert thrust to yaw the vehicle?

amon · « **Reply #53 on:** 03/25/2006 12:17 am »

All I hear at the end is "we have an active track with the radar (garble)"

edstrick · « **Reply #54 on:** 03/25/2006 12:18 am »

Looking at the video posted on the site...

From the moment of propulsion system failure to maybe 7 seconds before impact, there is a high rate of data dropouts in the compressed video. The dropouts then disappear and the video is "clean" till loss of signal. The cylindrical shape of the venicle below the camera port seems to have entirely disappeared from the video at or before that point, suggesting the upper stage may have broken apart from the first stage due to aerodynamic forces after loss of control.

The failure could plausibly be caused by the thermal blanket THWAPPING exposed plumbing and hardware in the unshielded engine "compartment". Like the Gemini's Titan 2, the Falcon has no aerodynamic shield around the engine hardware above and around the thrust chamber, rendering it potentially vulerable to "debris intrusion".

We'll see if this combines two parts of the puzzle into one failure mechanism.

DaveS · « **Reply #55 on:** 03/25/2006 12:20 am »

The last comm on video is this: "This the RSO, we have an active track with the radars." Nothing else is said.

Shuttle Man · « **Reply #56 on:** 03/25/2006 12:22 am »

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edstrick - 24/3/2006 7:18 PM

Looking at the video posted on the site...

From the moment of propulsion system failure to maybe 7 seconds before impact, there is a high rate of data dropouts in the compressed video. The dropouts then disappear and the video is "clean" till loss of signal. The cylindrical shape of the venicle below the camera port seems to have entirely disappeared from the video at or before that point, suggesting the upper stage may have broken apart from the first stage due to aerodynamic forces after loss of control.

The failure could plausibly be caused by the thermal blanket THWAPPING exposed plumbing and hardware in the unshielded engine "compartment". Like the Gemini's Titan 2, the Falcon has no aerodynamic shield around the engine hardware above and around the thrust chamber, rendering it potentially vulerable to "debris intrusion".

We'll see if this combines two parts of the puzzle into one failure mechanism.

I'm inclinded to agree with that statement.

mr.columbus · « **Reply #57 on:** 03/25/2006 12:23 am »

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edstrick - 24/3/2006 8:18 PM

The failure could plausibly be caused by the thermal blanket THWAPPING exposed plumbing and hardware in the unshielded engine "compartment". Like the Gemini's Titan 2, the Falcon has no aerodynamic shield around the engine hardware above and around the thrust chamber, rendering it potentially vulerable to "debris intrusion".

As I said above, that seems the most plausible explanation to me right now as well.

Tap-Sa · « **Reply #58 on:** 03/25/2006 12:23 am »

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hyper_snyper - 25/3/2006 3:16 AM
The termination sequence forces the Merlin to divert thrust to yaw the vehicle?

If you want to terminate thrust immediately an efficient way is to redirect turbopump exhaust to somewhere else than combustion chamber ie. overboard. Perhaps small charges rupture the lines going from the pumps to the chamber. Pure speculation on my part, don't know how the SpaceX thrust termination actually works. If someone out there does, please tell us.

David AF · « **Reply #59 on:** 03/25/2006 12:24 am »

How long until SpaceX will be ready for a second attempt, by way of an estimate? A year? Two?