I think that was an outsourced Parker Hannifin assembly (See wiki article). Accidents are usually attributed to an airplane manufacturer, when they are most accurately attributed to supplier. People think the airplane manufacturer knows all and sees all when the opposite is the truth, they are along for the ride on most of the sub-assemblies. This is what happened with the 787 batteries as another example. A lot of trust is placed at the supplier level to produce and test a safe part, but it does not always work out.

Cub,
All very true and I should have made the distinction of the valve being a vendor item...

my 1st thought

Well said!

I would venture to guess that far more accidents have been caused by stall avoidance system malfunctions than actual stalls.

Could be.....

I think accidents as a result of poorly executed simulated emergencies tops the list.

comments on gust lock similar to most in this thread ... mechanical/electromechanical/software ... pilots inputed elevator authority and ****z happened ...IMHO

Maybe, but what if this valve failed in flight?...I've been flying a fly-by-wire airplane for the last few years and still don't like it, but to not be able to override a "Stick Pusher" type system scares me more...:eek:

A light fuel load like they would have had going to Atlantic City would give them no reason to take off flaps 10. Their takeoff configuration would have been flaps 20 for sure.

As for the bad design of the stall barrier valves, the slightest bit of checklist discipline would prevent a problem in this area. On the after start checklist, the stall barriers are tested for the first flight of the day, but the flight controls are checked after every start AFTER the stall barrier check. The G4 is a solid airplane and all prior fatal accidents have been 100% pilot error.

The pilots can override the stall barrier/stick pusher (different than stick shaker) with the autpilot disconnect button on each yoke. After engine start you're supposed to test that the stick shaker works, then the pusher fires at a higher AOA and the AP/DISC button allows you to override the pusher.

The gust lock would have prevented them from moving the throttles more than a knob-width or two above idle; no way they would have achieved takeoff speed with the lock on.

But, here's one for folks smarter than me on the G-IV. You're not supposed to start the engines with the gust lock on because it messes with the flight controls; I've never inestigated HOW it affects the controls. If you DO start the engines with the gust lock on, you're supposed to shut down both engines and bleed off all hydraulic pressure BEFORE releasing the gust lock, then restart and you're on your way. Anybody know how it would affect the flight controls if you started engines with the lock on, didn't shut down/bleed pressures, released the lock and pressed on for taxi/takeoff?

With how quickly the NTSB has been releasing DFDR data I'm sure we'll know more very soon.