Discussion Topic |
|
This thread has been locked |
| Messages 1 - 16 of total 16 in this topic |
stevep
Boulder climber
Salt Lake, UT
|
|
|
Oct 31, 2014 - 12:53pm PT
|
Rough week for private spaceflight.
And fairly amazing that one of the pilots might survive such an accident.
|
|
pyro
Big Wall climber
Calabasas
|
|
|
Oct 31, 2014 - 05:41pm PT
|
no bueno!
bad news for public space travel.
|
|
johntp
Trad climber
socal
|
|
|
Oct 31, 2014 - 05:44pm PT
|
deleted my thread. seems like they were using experimental fuel.
|
|
Flip Flop
Trad climber
Truckee, CA
|
|
|
Oct 31, 2014 - 05:46pm PT
|
"Serious anomaly".
|
|
Bad Climber
climber
|
|
|
Oct 31, 2014 - 06:06pm PT
|
This is an incredibly sad day for us in the Mojave/Tehachapi area. While the killed pilot was not a close friend, I knew him well and often stopped to talk to him and his wife and lovely children when we'd stroll the neighborhood on warm summer evenings. Their loss is impossible to imagine. We just got the news after a day out rock climbing, feeling good, loving life, which is the best we can do. Be grateful for each day, for the friends and loved ones in your life, rejoice in the sun and rock and sky. You never know when it will all be taken away.
BAd
|
|
Levy
Big Wall climber
So Cal
|
|
|
Oct 31, 2014 - 07:18pm PT
|
about a year ago, I saw the mother ship, the launching vehicle doing some flying around Mojave. It was such an unusual looking aircraft I had to stop and snap some photos. Unfortunately I don't have access to them now but it's a wild looking aircraft. It looks like a Sykorskycrane on steroids. my condolences to the family of the deceased crew member.
|
|
climbski2
Mountain climber
Anchorage AK, Reno NV
|
|
|
Oct 31, 2014 - 08:12pm PT
|
Anyone helping push the envelope of human endeavor in space is a Hero to me. While not a part of NASA I hope this guy is remembered the same as any lost member of space programs have been.
|
|
ß Î Ø T Ç H
Boulder climber
extraordinaire
|
|
The explosion came after the plane ... fired up its hybrid rocket engine. never been a big fan of space travel etc.
Sketchy technology -- explosions and burning up on reentry, what have you.
|
|
Reilly
Mountain climber
The Other Monrovia- CA
|
|
This has to affect the 'market' of the 750 people who have shelled out $250K deposits.
|
|
Gunkie
Trad climber
East Coast US
|
|
|
Topic Author's Reply - Nov 1, 2014 - 08:52am PT
|
Having built solid rocket motors and been around hybrids, I have some understanding of the internal dynamics associated with each. Hybrid rocket motors are optimal for this kind of application. They don't have a huge initial thrust, can burn for an extended period of time, and can be throttled.
My understanding is the solid portion of the rocket motor was changed from a rubber based fuel to a plastic fuel. Just on the face of it, I bet the fuel grain cracked which would instantaneously cause a much larger area of the fuel grain to be involved with the burn (burn area increase) and the combustion chamber, which also contains the fuel grain would over-pressurize. Now the rocket motor was probably designed to fail in such an instance where the aft end of the motor would fail causing the end of the flight, but not in a catastrophic way. The pilots would be surprised, but the airframe should have stayed intact. BTW, if you had this fuel grain not constrained in a motor casing and lit it in your driveway, it would basically smolder and might barely hold a flame.
Based on some of the images I've seen, the motor failure left a large white plume. What that tells me is the forward end of the solid portion of the motor failed and the oxidizer tank ruptured causing the destruction of the airframe. The oxidizer tank may have punched through the cockpit; I don't know. But looking at the images just after failure, the airframe is broken in half which would be consistent with that kind of failure.
EDIT: Looking like pilot error not motor failure.
SpaceShip Two’s fuel tanks and engine were recovered largely intact. The hybrid motor fueled by nitrous oxide and a plastic-based compound was found some 5 miles from where large sections of the tail first hit the ground.
|
|
Bad Climber
climber
|
|
|
Nov 10, 2014 - 12:43pm PT
|
Since I've talked to people close to the incident, this report linked below is a pretty good account of what happened. There was no problem with the engine. Pilot error.
http://www.theguardian.com/science/2014/nov/07/virgin-galactic-tragedy-revealed-spaceshiptwo-disaster
On another note, friends and colleagues from Scaled Composites have been running continuous protection from the media for the widow and her children--awesome! They park in front of her house and drive off the emotional vampires and their cameramen when they show up. Fortunately, it looks like the TV crews have largely given up.
BAd
|
|
Reilly
Mountain climber
The Other Monrovia- CA
|
|
|
Nov 10, 2014 - 12:48pm PT
|
It certainly looks like a problem of poor checklist design and/or procedural failure.
That said it also seems like a design flaw to even allow the arming of the
deployment switch prematurely. It may transpire that there was a software
or electronic/electrical failure too.
|
|
Bad Climber
climber
|
|
|
Nov 10, 2014 - 12:55pm PT
|
Hey, Reilly--
My thoughts, too. Seems like the system could be designed to make such an action impossible.
BAD
|
|
SteveW
Trad climber
The state of confusion
|
|
|
Nov 10, 2014 - 03:44pm PT
|
Badclimber--amazing story!
|
|
NutAgain!
Trad climber
South Pasadena, CA
|
|
|
Nov 10, 2014 - 04:03pm PT
|
People complain about late and over-budget government projects, but it takes a lot of work, and it's hard to accurately forecast, when you focus on making something work well and catch all stuff like this.
In theory this scenario could have been thought of as part of a testing/design process... but in practice it would have been a lot lot more expensive and long time to get to the launch point. And maybe the funders would have refused if they knew how long it would really take to get to the finish line with less risk to human life. Unless you spend an inordinate amount of time going through every micro-step of a process, it's too hard to think of everything that can possibly happen and prevent it. Even then you're just mitigating risk- not preventing it. And when money is being trimmed from a budget, just speaking in nebulous terms like "deeper level of testing and evaluation" doesn't cut it. You don't know what you don't know ahead of time. And for a project of this complexity, the comprehensive test processes that are already in place probably exceed the scope of understanding for any human and require teams of exceptionally talented people to put it all together. Even testing different subsystems exhaustively, it's hard to know what you don't know about other areas that may interact with your subsystem in unforeseen ways. The bottom line, it's difficult.
These guys made a sacrifice for the expansion of humanity beyond earth. It's a huge loss, a historical marker in a series of steps and setbacks that characterize the advancement of our civilization.
|
|
| Messages 1 - 16 of total 16 in this topic |
|
SuperTopo on the Web
|
Let us know!