Virgin Galactic Test
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red_slr

Original Poster:

20,640 posts

218 months

Thursday 31st May 2018
quotequote all

https://www.youtube.com/watch?v=fsPHywoQZWA

Interesting footage. Looks pretty tricky to fly to me, very pitch sensitive. (as a non pilot!)

I would have thought that they would have a flight computer similar to the Shuttle or Space X but quite a lot of control inputs going in there!

redface

Cool stuff!!

Eric Mc

125,606 posts

294 months

Thursday 31st May 2018
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I think this aircraft is not designed to be "unstable" in normal flight modes. In other words, it doesn't NEED a computer fly by wire system to enable it to be flown.

The Shuttle was aerodynamically unstable so it absolutely needed a fly by wire system in order to keep it from going out of control. The reason why the Shuttle was unstable was because, in the 1970s, it was not possible to build an aircraft that could maintain aerodynamic and centre of gravity stability throughout flight regimes that went from Mach 22 to about 200 knots. Indeed, the Shuttle also needed ballast just to keep the centre of gravity within a range that kept it from flipping. In fact, I'm pretty sure that any flying vehicle that is desgined for such a range of speeds will still need computer control.

Spaceship 2 system does not go much beyond Mach 3 so can get by with conventional controls.

Piginapoke

5,983 posts

214 months

Saturday 2nd June 2018
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Odd front landing gear? No nose wheel, just a skid I think.

MB140

5,030 posts

132 months

Saturday 2nd June 2018
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Anyone else seen the air crash investigation program on the one that crashed.

Looked very complicated in the take off and transition phases.

Basically crashed and killed one of the two pilots because they unlocked the rear pivoting section too late (at too higher speed) during the acceleration phase.

What I thought was unbelievable was the complete lack of protection systems to prevent inadvertent operation.

Apparently the co-pilot had made a similar mistake in the simulator previously. SOP is to abort the flight if you fail to unlock it between certain speeds which obviously is hugely expensive and embarrassing. Surely a simple electromechanical lock on the lever to unlock the pivot mechanism should have been in place but they deemed the test pilots flying these would be good enough not to make a mistake. Glaring error to believe a human (no matter how good would never make a mistake), especially on a safety critical system.

Either way it’s interesting to see it’s development.

Cant find a link to the documentary but the following gives a reasonable account.

https://en.m.wikipedia.org/wiki/VSS_Enterprise_cra...

Edited by MB140 on Saturday 2nd June 22:57

dr_gn

16,924 posts

213 months

Sunday 3rd June 2018
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Piginapoke said:
Odd front landing gear? No nose wheel, just a skid I think.
Not unusual to have skids on aircraft that don't need to take off under their own power or maneuver on the ground - relatively simple and saves space and weight.






Eric Mc

125,606 posts

294 months

Sunday 3rd June 2018
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Quite a popular choice for rocket powered aircraft.