Air France 296 Question

jwp_145 said:
Was this flight a revenue flight? ...as in passengers on board?

For those who are unfamiliar with the accident, here is the wiki article...

http://en.wikipedia.org/wiki/Air_France_Flight_296
Click to expand...
No, it was actually a prize won by those aboard to demo the then new A320 at an airshow. As we now know, it wasn't a very good demo of the FBW system (Which even to this day, with the very limited knowledge I have of it, I'm still skepticle about)
 
A150K said:
No, it was actually a prize won by those aboard to demo the then new A320 at an airshow. As we now know, it wasn't a very good demo of the FBW system (Which even to this day, with the very limited knowledge I have of it, I'm still skepticle about)
Click to expand...

It's virtually the same control law that Boeing uses, except Boeing makes you have to trim for some bizarre reason. Anyway, that accident had NOTHING to do with FBW.
 
seagull said:
It's virtually the same control law that Boeing uses, except Boeing makes you have to trim for some bizarre reason. Anyway, that accident had NOTHING to do with FBW.
Click to expand...
Like I said...I know next to nothing about he system. It's the idea of the computer having the final authority that scares me a little bit...Maybe my skeptisism is out of ignorance.
 
A150K said:
Like I said...I know next to nothing about he system. It's the idea of the computer having the final authority that scares me a little bit...Maybe my skeptisism is out of ignorance.
Click to expand...

Saying that FBW had nothing to do with the accident is a also little disingenuous. The pilot and the machine conflicted, and caused the accident--l'capitan did not understand Alpha Floor and Alpha Max, if Fly By Wire is to be believed (recent book on Sully's successful ditching) is to be believed. Again, accidents are a chain: if the bus had been more conventional (or the captain not misinformed/ignorant about his aircraft) the accident would not have happened.

Tinfoil hats take note that the FDR was apparently tampered with...:bandit:
 
That's not the kind of prize that I ever want. I'm guessing the airshow/prize factor played into the fact that the pilots were charged with manslaughter.
 
I wasn't trying to start an A vs B debate, or an FBW against nonFBW debate... I was just curious if it was a revenue flight, at which point my next question would've been "How were they doing low passes on a revenue flight?!?"
 
I think this is a live video of this crash. You can hear the engines spool up before it crashes in the trees, but too late.

This is how I understand it: The pilot was supposed to demonstrate the alpha-floor protection that automatically sets the thrust at TOGA thrust when the aircraft reaches a very high angle of attack. Alpha-floor is available from lift-off until the aircraft reaches 100ft RA in approach. Unfortunately, the aircraft was 30 feet from the ground, and it didn't kick in. Pilot error.

[YT]SCwYAzqvcrQ[/YT]
 
I thought he just got low and slow with the engines un-spooled, then tried to pull up while already at a high Alpha, which made the FBW say "no thanks, I won't let you get that close to a stall" so the airplane just sank into the trees as the engines finally started to spool up. But Orange Anchor is the man to talk to on this...
 
Roger said:
I thought he just got low and slow with the engines un-spooled, then tried to pull up while already at a high Alpha, which made the FBW say "no thanks, I won't let you get that close to a stall" so the airplane just sank into the trees as the engines finally started to spool up. But Orange Anchor is the man to talk to on this...
Click to expand...

you're right, it's possible the flight computers prevented the aircraft from stalling, which is a good thing. The problem came from the pilot not realizing that the alpha-floor protection would not kick in and not executing a go around before it was too late. IMO.
 
Roger said:
I thought he just got low and slow with the engines un-spooled, then tried to pull up while already at a high Alpha, which made the FBW say "no thanks, I won't let you get that close to a stall" so the airplane just sank into the trees as the engines finally started to spool up. But Orange Anchor is the man to talk to on this...
Click to expand...

Someone (seagull?) already corrected me on this on another thread. Your take is spot on, it seems. I still like my version better, but it lacks some shine because it's, you know, not true.
 
Nanopilot said:
I think this is a live video of this crash. You can hear the engines spool up before it crashes in the trees, but too late.

This is how I understand it: The pilot was supposed to demonstrate the alpha-floor protection that automatically sets the thrust at TOGA thrust when the aircraft reaches a very high angle of attack. Alpha-floor is available from lift-off until the aircraft reaches 100ft RA in approach. Unfortunately, the aircraft was 30 feet from the ground, and it didn't kick in. Pilot error.
Click to expand...

Someone who's an Airbus guy should tell us how flaring the airplane works from a flight control system standpoint. (This isn't your grandpappy's DC-7. :) ) Something about a nose-down trim increment being added to allow you to flare the airplane - not normally possible in Normal Law otherwise - (no, I don't have an FCOM available to me at the moment, otherwise I'd happily RTFM).
 
Autothrust Blue said:
Someone who's an Airbus guy should tell us how flaring the airplane works from a flight control system standpoint. (This isn't your grandpappy's DC-7. :) ) Something about a nose-down trim increment being added to allow you to flare the airplane - not normally possible in Normal Law otherwise - (no, I don't have an FCOM available to me at the moment, otherwise I'd happily RTFM).
Click to expand...

I'm not an "Airbus guy", but can tell you that the "normal law" essentially sets a rate. I do not know if what you say is correct, but can say that things are added into the system to make you do things that you would otherwise not have to do in a FBW aircraft, but they are added to make it fly more like it's not FBW. The basic control law for the Airbus is the same as for Boeing, C*, with the Boeing adding in a U interface which artificially makes it so you have to trim the aircraft. Obviously, there is no reason that a pilot should have to trim in a FBW system, so they do that only to make it seem like a conventionally controlled aircraft. I would guess that the above is similar, forcing you to hold back pressure that would otherwise not be required. Again, I do not know that they added this feature you describe, but can think of reasons why you would do it.
 
seagull said:
I'm not an "Airbus guy", but can tell you that the "normal law" essentially sets a rate. I do not know if what you say is correct, but can say that things are added into the system to make you do things that you would otherwise not have to do in a FBW aircraft, but they are added to make it fly more like it's not FBW. The basic control law for the Airbus is the same as for Boeing, C*, with the Boeing adding in a U interface which artificially makes it so you have to trim the aircraft. Obviously, there is no reason that a pilot should have to trim in a FBW system, so they do that only to make it seem like a conventionally controlled aircraft. I would guess that the above is similar, forcing you to hold back pressure that would otherwise not be required. Again, I do not know that they added this feature you describe, but can think of reasons why you would do it.
Click to expand...

Man, 25 years of flying and I feel like a dog watchin' TV when reading this thread! :)
 
You must log in or register to reply here.
Back
Top