Virgin Galactic problem

The copilot released the lock, which is the first step in the two step procedure to go to high drag mode. Unfortunately, that lock was designed specifically to prevent the high drag setting from occurring in dense air. When he released the lock, the air loads overrode the second part of the release sequence and she popped open. He was the one who did not make it, so hopefully the pilot knows why the lock was released way before apogee and start of descent, where it should have been released.

 

Seems like co-pilot error.

 

Test pilots have an amazingly fun job (to me) and they bear risks.

One of those risks is sticking strictly to the flight test program with I would presume very strict checklists. I'm a type rated jet pilot but I don't know test pilot procedures firsthand but I presume everything is done BY THE BOOK that was created for THAT particular flight.

If something was done out of order, that would be very odd for a seasoned test pilot or any pilot for that matter. If they were reacting to an anomaly and "tried" something, not described in the test protocol, to help then all bets are off and the pilots should do whatever they think is best...

 

I don't want this taken the wrong way, and I have a great deal of admiration and respect for the guys that strap themselves into these things on all of our behalfs...

I'm somewhat relieved that the cause (at this early date) appears to be simple human error as opposed to problems with the technology.

Make sense?

 

My thoughts as well. A rocket motor failure (initial reports suggested an explosion) would have been a "back to the drawing board" kind of event.

 

Was thinking the same. Whatever the final conclusion another positive is that this is a privately funded venture. While they will ultimately have to prove to their customers that the product is safe, they are not hampered by the governmental BS/PC red tape and thus can proceed at a much faster pace to getting aloft again.

 

I'm certain this aircraft will have to be certified by the FAA once it is ready for commercial operation. That's serious red tape. The certification paperwork often weighs more than the aircraft.

 

There are no FAA regulations regarding such a craft. It will be granted an experimental ticket if anything. For rocket launches I believe the FAA just grants various waivers/exemptions.

 

Jim- We (DARPA, etc) work regularly with the FAA on RLV regulations, and so does Virgin and Scaled Composites. They are trying to stay ahead of the game on future space applications. Expected casualties in the event of a crash is a big part of the discussions.

 

I'm not aware of any experimental (X) registered craft allowed to be used in revenue/commercial service?

 

Here is what I can glean so far. The feather lock was relased prematurely. In theory from the way virgin and sacled was intialy talking this should not cause the feather to take place, its just the relase of a lock, which is the first part of a two part process to feather..

Now it seems that with the lock relased aeordynamic pressures forced the feather mecahnism to move. It seems the scaled is also suprised that with the lock released aero pressure woudl be able to cause this condition.

Perhaps the most surprising part of the whole story is how the one co-pilot manged to get from the right seat, acorss the cabin to the door on the lower left, open it and get out.
The breakup occured at 51 000 feet, did the stay in the pressure capule till a lower altitude, was the capsule stable and intact? Did it have athmosphere. At what altidude did he open the door and get out, did he skydive down how did he avoid hypoxia. there is an amazing human survival story here.

Yeah the second ship is 2/3 complete, and changes they may be able to incorporate. NHTSA says they can continue testing while the investigation takes place. My guess si they have a pretty good idea by now what happened, if not why. They can compleet the second ship and incorporate any number of changes and 12 months from noww e wills ee the new ship testing with passenger flights sometime in 2016.

 

Any regs in the near term for a RLV will not look anything like regs for Part 23 or 25 aircraft. Even the White Knite will require a huge number of waivers/exemptions/ELOS's in order to fly under current FAR's.

That's good, in that the FAA would not have any practical knowledge of RLV's. In reality it seems this should not even be the under the umbrella of the FAA, but I guess there is no one else suitable either. Maybe the government should just stand back. There was no FAA (CAA) during the formative yrs of powered flight.

One thing to remember, no Scaled prototypes have ever transitioned to a successful certified product. Maybe if they are helping to write the regs that will be different.

 

One article stated that the lock was supposed to be released at M1.4, but was released just past M1.0. Speed and density altitude would play a big role in the actual aero forces.

 

And the transonic shock wave wouldn't help things with something unlocked that shouldn't have been.

 

OK - but here is what I do not understand: How would releasing the lock at a lower speed increase the aero forces?

 

The rather turbulent air around the "sound barrier" looks like the problem. Things smooth out as speed increases beyond mach 1. Leaving the locks in place until mach 1.4 takes advantage of that.

 

Apparently, he is out of the hospital.

Virgin Galactic pilot defied the odds to survive crash - LA Times

 

News story I read made him sound close to death, now he's out walking around?

Good for him. Glad he's OK.

Must be quite a ride at M1 at 50k or so without benefit of an airplane. Think I'll pass.

 

James- The difference is the altitude and air density. The system was not designed to be deployed in relatively high density air. It was designed to be deployed at much higher altitude, where there is very little air. We see this all the time on launch vehicles where the engines are throttled back as max q or max air loads are reached to prevent damage to the aeroshell. As altitude increases and air density decreases, the engines can be throttled back up.

The big problem with reentering an RLV from high altitude and low airspeed is there is very little drag to slow the vehicle and you then tend to over-g her on pull out in denser air at lower altitudes. At mach 5 or so and 300,000' air density and air loads are very small, and without high drag devices, you could see g forces in excess of 100 on pull out. The feathers are an ingenious way of generating high drag at low air densities. They and the fuselage are not designed to take the air loads of the feathers opening in dense air, which is what happened.

 

The reason this works for the Rutan design is because they are only on a ballistic type trajectory, e.g. up and then right back down. This design would not work if returning from orbit, unless they had large re-entry burn to essentially stop themselves in orbit and just drop. This is also why they get by with a less exotic heat shield, since they are not doing M20 during reentry.

 

Jim- Affirmative, not a problem from higher mach numbers where you generate lift at very high mach numbers in very thin air. Something like the Hypersonic Test Vehicle with a high hypersonic L/D generates enough lift to glide up to 15,000 nm from a mach 25 reentry seeing very low g loads. Spaceship 2 is a special case, high altitude and no velocity, not unlike the X-15, which was made of inconel.

 

About 2/3 complete at this point.

Virgin Galactic pilot defied the odds to survive crash - LA Times

Work is ongoing.

 

The story of how he got out and back to earth is an epic tale

 

Yes, that does make sense - not the airspeed per se, but the aero density loading.