It's been 16 months since SpaceShipTwo crashed into the Mojave Desert and killed the vehicle's co-pilot Michael Alsbury. On Friday, Virgin Galactic sought to move on from that accident and put the company firmly back on a path toward delivering tourists to the edge of space by unveiling a new version of its spacecraft named VSS Unity.
"I'm really proud of the entire team," said George Whitesides, chief executive of Virgin Galactic, in an interview with Ars. "It's a bunch of folks who came to this company to open space up, and they're not going to be deterred by the accident. They've been working really hard for a year and a half to finish this vehicle."
The new spacecraft is in many ways the same as the original SpaceShipTwo, dubbed Enterprise, Whitesides said. It has the same basic airframe and propulsion systems. The biggest change is to the feather locking system, used to aid in the descent of the spacecraft. During the fatal flight on Oct. 31, 2014, Alsbury prematurely deployed the system while still making a powered ascent. Unity now includes a mechanical pin to prevent the feather lever from moving when the vehicle is flying in an unsafe flight regime.
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Virgin Galactic conducted its first test flight of its SpaceShipTwo suborbital vehicle in more than five months Jan. 11 as the company prepares to begin powered test flights of the vehicle.
The glide flight, conducted in the skies above the Mojave Air and Space Port in California, was the seventh for the second SpaceShipTwo, named VSS Unity, dating back to December 2016. Pilots Mark Stucky and Michael Masucci landed the vehicle at the airport after a successful flight.
The glide flight was the first for SpaceShipTwo since one in early August. The company said in a statement that it had spent the intervening months on "extensive analysis, testing and small modifications to ensure vehicle readiness for the higher loads and forces of powered test flight."
Virgin Galactic tested those modifications on the glide flight, as the pilots pushed the vehicle into a steep descent shortly after release from its WhiteKnightTwo carrier aircraft, reaching a top speed of Mach 0.9. That is the fastest the vehicle can fly without igniting its hybrid rocket motor, according to the company.
This flight may be the last glide test before the vehicle begins powered test flights. "I think we'll probably do one more glide flight, and then we'll be ready to go into powered flight," George Whitesides, chief executive of Virgin Galactic, said in a presentation at the Next-Generation Suborbital Researchers Conference in Broomfield, Colorado, Dec. 18.
[...] Virgin Galactic's first SpaceShipTwo, VSS Enterprise, was lost in an accident in a powered test flight in October 2014, the fourth for that vehicle. An investigation by the National Transportation Safety Board concluded the vehicle's co-pilot prematurely unlocked the feathering system for the vehicle that raises its tail for reentry, causing the vehicle to become aerodynamically unstable and break up as it passed through Mach 1. The investigation also blamed vehicle designers for not including safety systems that would have prevented the feathering system from being unlocked during that phase of flight.
Source: http://spacenews.com/spaceshiptwo-performs-glide-flight-in-advance-of-powered-tests/
Related:
- Virgin Galactic Spaceship Makes First Glide Flight
- Virgin Galactic moves on from crash, debuts flashy new spaceship
- Virgin Galactic Crash Due to Pilot Error and Design Flaws
(Score: 4, Informative) by VLM on Sunday February 21 2016, @01:48PM
Better link:
https://en.wikipedia.org/wiki/VSS_Enterprise_crash [wikipedia.org]
The ARS link is to an article posted right after the crash so the article is mainly speculation on exploding engines, whereas it was pretty quickly proven to be an aerodynamic problem. The ARS article isn't bad, its just long obsolete.
Everyone piles hate on to the engine, which is interesting. The fact that the engine hasn't blown up yet, or that failures so far have involved other systems, doesn't necessarily prove its a good engine system. It is interesting how everyone hate that engine system. You'd think the aero issue time would be a great opportunity to slap in a better engine system, but...
I am a little confused about the pin-in-place solution. If you want to lock the parts in place during boost, simply don't unlock them after motor firing as they did in the fatal crash. Of course after a trip thru the journalist filter, maybe thats exactly what they're doing, plus or minus something like the feather unlock lever can't be moved until after engine shutoff due to a new pin.
My guess is they always unlocked but this time there was just the wrong vibration or buffeting or weird wind or whatever such that it swung, and all the other flights it was just smooth enough or different vibration freq or whatever. So just don't unlock the feather control during boost, then call it good... On the other hand if the O2 failed during boost they might live if they auto feathered down, so having to manual feather means if they pass out on boost, they'll lawn dart into the desert, which sucks. Or more likely break up when they hit mach 7 on the way down, etc.
(Score: 1) by khallow on Sunday February 21 2016, @07:53PM