What really happened aboard Air France 447

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skyking

Lifer
Nov 21, 2001
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It's not the same as 200mph worth of wind on the ground though. The much thinner air at altitude doesn't have exactly the same impact.
Think about that for a minute. Wind is relative to the earth; an aircraft flies in this moving "sea" of air. 200 MPH is 200 MPH, as far as ground speed and vector are concerned.
I think you may be referring to indicated vs true airspeed at altitude.
Typical winds aloft are in the 40~80 knot range at the mid-30s, weaker in summer months and stronger in winter. Wierdest I've seen is light and variable through about 15,000 feet. Even that day it was blowing more than 30 knots in the 30's.
 

rudder

Lifer
Nov 9, 2000
19,441
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91
Ground speed is of no use whatsoever to the pilots while in flight, actually.

My destination is 300 miles away. I am going 100 mph indicated. I have 3.5 hours of fuel. Headwinds are a straight on 50 mph. Will I make it?
 

rudder

Lifer
Nov 9, 2000
19,441
86
91
:rolleyes:
How much experience do you have flying airliners? LOL


People a lot smarter then you and your pony boy have spent their entire working career designing these flight control systems and trust me, if it wasn't safe, the airliner would not have been certified for passenger travel.

I am not familiar with the fly by wire 777 or 787... but at least on many Boeing airplanes if you are doing a control movement counter to the captain...he is going to know about it and yell at you to get off the fucking yoke.
 

DominionSeraph

Diamond Member
Jul 22, 2009
8,386
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People a lot smarter then you and your pony boy have spent their entire working career designing flight control systems

Yes, and those people all work at Boeing.

if it wasn't safe, the airliner would not have been certified for passenger travel.

You're use of faith to try to fill ignorance is not a logically sound method of filling ignorance.

"I'm sure somebody thought of everything," is something that stupid people think as they sit in the protected cradle of mechanisms that people smarter than them have come up with. Smart people, OTOH, know just how difficult it is to think of everything, and we are quite aware that sometimes we just miss shit.

The A320 uses the same control scheme and statistically it is the safest airliner in the world

And how many crashes would it take for it to lose that by a wide margin?

How many near misses has the A320 had because of this, where there was momentary confusion in the cockpit caused by both front seaters trying to input flight commands? We don't know. In a non-emergency situation the pilots would be able to figure out relatively quickly the point of failure -- two hands on stick -- but in an emergency how do you tell the difference between wonky controls because of averaged controls and wonky controls because of mechanical failure/unexpected aerodynamic forces?

Asynchronous averaged controls places a huge hurdle right in a pilot's troubleshooting path. If you are testing the bounds of an aircraft's response, deflection right has to equal airplane "roll right", left has to equal roll left, up has to equal up, down has to equal down, left rudder has to equal yaw left, and right rudder has to equal yaw right -- all in a 1:1 relationship. It is the variance from 1:1 that you would use to tell you there was something wrong with the aircraft, and you would start thinking, "What would make it not respond correctly in the exact manner it just did?" But with averaged controls in conflict it IS responding correctly -- it's just your concept of "correct" is wrong because it's literally out of your hands; the averaging program is making the determination of the "correct" control input and it's simply not telling you what that is.
 
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JulesMaximus

No Lifer
Jul 3, 2003
74,528
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Yes, and those people all work at Boeing.



You're use of faith to try to fill ignorance is not a logically sound method of filling ignorance.

"I'm sure somebody thought of everything," is something that stupid people think as they sit in the protected cradle of mechanisms that people smarter than them have come up with. Smart people, OTOH, know just how difficult it is to think of everything, and we are quite aware that sometimes we just miss shit.

Sounds like the Airbus was designed by engineers... not by pilots.
 

alkemyst

No Lifer
Feb 13, 2001
83,769
19
81
lighten up there Frances, I spent a lot of time explaining that to students who now have licenses :p

QFT, despite many thinking these kinds of things are so obvious most can't do the mental math.

Worse is drawing a 2D image that needs to be cut/folded into a 3D image. Many can't even handle simple shapes.

Part of succeeding in life is knowing this.

If everyone was as smart as I was, I wouldn't have a job. If I blamed everyone for not being as smart as I am, I wouldn't have a job.
 

CallMeJoe

Diamond Member
Jul 30, 2004
6,938
5
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Stall warning is inhibited at IAS of less than 60 knots, I believe. This is to silence it when you are landing, I think. It would also be inhibited with clogged pitot tubes, since the IAS might read below 60 knots...

I have worked avionics for >30 years and have yet to see an aircraft that inhibits stall warning at low airspeed. We test stall warning and landing gear warning systems in the hangar with aircraft on jacks; zero airspeed and the warnings work just fine.
 
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XX55XX

Member
Mar 1, 2010
177
0
0
Being a dude who has only dabbled in FSX and nothing more...

I can't believe this co-pilot kept his stick back for that long. It seems counter-intuitive, even to wannabe pilots like me. And two years ago I kept thinking that it was a massive hardware failure of some kind.