Posts by John Hargrove

Autothrottle problems suspected in Heathrow 777 crash

...wait a minute...

Where did I ever imply these airline pilots are not qualified? Anon Coward seems to think I'm attacking pilots, or airliners, or programmers, or God knows who else!

This is an opinion forum, and, being a pilot, I think I have as much a right to an opinion as most of the other intelligent posters on this thread.

Of course little tin SEL's are not the same as turbine airliners; of course low-time (relative to the airline jet jockeys) white-knucklers cannot even approach the skills and training of jet pilots; of course guys who program and plan the computer control systems of complicated aircraft work long and hard anticipating every eventuality; of course... well, enough.

I'd still feel better back in my passenger seat if the guys up front could over-ride computer control systems if they had to.

And that's all I'm going to say.

Now, where did I leave my sunglasses? :^)

...wait a minute...

James and Vladimir - Thanks for your reminders of basic aerodynamics. I never seem to be able to get everything into any of my posts, so I apologize!

Given that, I don't think I will back off my contention that jet jockeys never like it when their fans drop below thrust rpm's. Flameouts occur at low rpm's, regardless of airspeed, wind shear/inertia complications, computers, what-have-you, and are even more likely in wind shear conditions. Being able to totally trust the computers to spool up the engines after approach zero-thrust rpm, in my reading and hangar-flying experience, is rare. Then, after beginning to spool up, to inexplicably drop back to zero thrust... well, another couple of sceptics are born, if they live long enough.

I'm not saying that lack of pilot over-ride caused the 777 engines to abort throttle-up inpupt instructions and flame out or drop back to zero thrust - I am saying that all pilots, fly-by-wire or with total computer control of engine speed, land with their hand on the throttle levers. We all learned that in basic flight training and it is so ingrained in us we probably would still keep our hand on the throttle even after the wings fall off, jet turbine or recip prop.

I continue to believe all aircraft should have pilot over-ride (computer by-pass) in their basic control systems, no matter how wonderful computers control the aircraft. 99.9% ain't good enough. In this forum several have played with the idea of external electronic incursion into the on-board computer system. If this is even only remotely possible, which I tend to see as VERY remote, a manual over-ride system seems desireable and even dictated.

...wait a minute...

I get the part about the manual movement of the throttle levers not being a real interactive pilot over-ride of the fly-by-wire system in the 777. What I don't get, is why is there NOT a real manual over-ride? Perhaps via a computer/throttle "kill" switch, or a physical set of throttle controls on an adjacent console? Cost avoidance? Fear of stupid pilots?

Also, all y'all air travelers, remember how OFTEN you've been on flights where those engines rev up before final throttle reduction to idle and set down? Pilots seem to love dropping below the red on the VASI and then dragging the bird in under spooled up power, because it takes too long for those turbines to spool back up after throttle input...(I think they just like to do carrier landings, myself).