Thread: Wow
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Old March 3rd 08, 08:48 PM posted to rec.aviation.piloting,rec.aviation.student
Bertie the Bunyip[_25_]
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Michael wrote in
:

On Mar 2, 9:17*pm, Bertie the Bunyip wrote:
Then there's the FBW Airbusses.
Every time I talk to one of those guys I walk away more confused
about how


the flight controls work than I was before.


And I hate to tell you this, but it shows.


Not in this case.


A good friend of mine (and in fact the guy who taught me to fly my
Twin Comanche when I bought it) went from captain of the DC9 to 727 to
A320 to 757, and has a lot of good things to say about all of them -
except for the A320. We're both engineers by training, so it only
took him about an hour or two to explain that flight control system to
me. Mostly my response was "What?!?!?!?" and "You gotta be kidding."



Well, that i can believe.

It's a perfect example of what happens when you allow the engineers to
design the user interface. It usually turns into something only an
engineer will want to use.



Couldn't agree more.


I saw this video when someone emailed me a link to it - before I saw
this thread - and I knew right away what sort of plane it was. I
can't recognize them by sight - but from the way it was behaving, it
was obvious what the pilot was trying to do - and why it wasn't
letting him. Only then did I really believe my friend.


Well, it depends.

I know you mentioned proportional mode upthread



No, I mentioned direct law.


- but it does not mean
what you think it means.

You still can not command a deflection - or
anything that would act like a deflection. What you command is a
rate. In other words, down low it doesn't do what it does up high
(your understanding is correct there) but it still doesn't act like an
airplane.

You can not slip an A320 - not even down low. Try to find an A320
driver who is trained as an engineer (and not one who scraped by on
C's) and he will probably be able to explain it to you. Once you
understand it, you will understand why the pilot did what he did, why
the crosswing limit is so low, and why you probably wouldn't have done
any better.


Maybe, but it's besides the point. I made it clear that whoever or
whatever decided to handle the airplane in the way it was handled, it
was the wrong way. I didn't say I would have done any better, BTW, and
at no time did I blame the crew. The reason I posted it in the first
place was to dispel the urban legend that airliners were kciked straight
and to illustrate what happens when they are..


Bertie