Flight envelope protection event involving an Airbus A320
Nothing has been mentioned here about
I would have thought this would be in the back of the mind of someone trying to stop an overspeed in one of these things: that if you don't, the aeroplane will pull up on you, busting a level.
Is this a consideration?
Originally Posted by ATSB Report page 4
If the autopilot remained engaged during an aircraft overspeed, the aircraft parameters use a 0.7 G input to raise the nose and reduce the airspeed.
Is this a consideration?
Bloggs- No that is not quite correct. If the overspeed is too high, then the autopilot will disconnect automatically and if the speed increases more, then an overspeed protection law takes over and then the nose will raise, and you can't stop it even from raising, even with full forward stick.
For minor overspends the autopilot remains connected and the FCOM procedure is to leave the autopilot connected and use speed brake.
For minor overspends the autopilot remains connected and the FCOM procedure is to leave the autopilot connected and use speed brake.
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the Pel-Air reportwas just an aberration?
I'm glad the Forsyth ASRR team thought that the Pel-air report was just an aberration...
Having just read the report, I think my list of 'why' questions might have ended up longer than the report! Have all the HF people left the ATSB or are they just banned from trying to give the industry some insight into how these got there and how others can be helped to avoid getting there.
Beakersville continues to dismally underwhelm...
Having just read the report, I think my list of 'why' questions might have ended up longer than the report! Have all the HF people left the ATSB or are they just banned from trying to give the industry some insight into how these got there and how others can be helped to avoid getting there.
Beakersville continues to dismally underwhelm...
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Do you blokes ever read your companies Operations Manuals?
It's all there you know, all the things you should do and what you shouldn't do!
That's not too hard is it?
PS: Any bloke who can't climb 2000' without invoking Alpha Floor shouldn't be in the front seat of any aircraft!
It's all there you know, all the things you should do and what you shouldn't do!
That's not too hard is it?
PS: Any bloke who can't climb 2000' without invoking Alpha Floor shouldn't be in the front seat of any aircraft!
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Too true
Alas Amos2, your statement that "Any bloke who can't climb 2000' without invoking Alpha Floor shouldn't be in the front seat of any aircraft!" is so true, but reality is - they are.
I love good ol Amos but I don't think he's ever flown an Airbus.........
The Airbus overspeeds very easily, you need to very very proactive during climb and descent especially in very strong winds ( or climbing into strong winds )
Slippery little suckers....
The Airbus overspeeds very easily, you need to very very proactive during climb and descent especially in very strong winds ( or climbing into strong winds )
Slippery little suckers....
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Hmmm!...I must admit I forgot that the super geostrophic winds, caused by climate change, didn't exist when I started flying the A320 in 1989. Don't think they existed when I was checking and training on the thing either.
Silly me!
Silly me!
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My post retirement golf, food and wine interests means that I log into Prune only when I have a few spare moments! Consequently, I have obviously missed out on reading " illusions " comments before they were deleted, I gather, by the Mods. Whilst I appreciate the show of support by the Mods, and other posters, this website is supposed to be for professional pilots, so comments by knuckle heads don't really bother me! 
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Read the fcom speed brakes are very slow to retract if used at height with A/p engaged. Rapid wind change causing o/speed then alpha floor is not uncommon in the bus. I only use the s/brakes as a last resort & carefully, in these situations.
On the A320 with the A/P engaged the speed brakes will only extend to the half way position, even if the lever is pulled back to full. If the A/P is then disconnected the boards go to the full position. This causes a huge increase in VLS (lowest selectable speed). If AoA protection kicks in brakes retract.
Why the QRH emergency descent procedure calls for full speed brake selection when with the A/P engaged only half will deploy anyway, and you will be caught out if the A/P disengages is a bit puzzling ?
In the event of an emergency descent the technique is to first allow the speed to increase before deploying the brakes. At high altitude and high weight with a 30kt coffin corner I would not want the brakes out unless I was descending and very closely monitoring the speed bands.
A delayed descent in managed mode will have the speed target uncomfortably close to the barbers pole, especially in turbulence. Also if speed brakes are used in managed descent, as soon as the aircraft thinks it is below the profile the engines will power up against the brakes (you do get a warning though).
Why the QRH emergency descent procedure calls for full speed brake selection when with the A/P engaged only half will deploy anyway, and you will be caught out if the A/P disengages is a bit puzzling ?
In the event of an emergency descent the technique is to first allow the speed to increase before deploying the brakes. At high altitude and high weight with a 30kt coffin corner I would not want the brakes out unless I was descending and very closely monitoring the speed bands.
A delayed descent in managed mode will have the speed target uncomfortably close to the barbers pole, especially in turbulence. Also if speed brakes are used in managed descent, as soon as the aircraft thinks it is below the profile the engines will power up against the brakes (you do get a warning though).
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There is a thread in Tech Log that goes into some detail regarding the different recommended methods for handling an overspeed at altitude. It would appear that Boeing & Airbus are quite different in their recommendations, with Airbus recommending power to idle first & Boeing recommending the use of speed brake first & power not below 60% N1 (B737NG).
http://www.pprune.org/tech-log/53879...overspeed.html
http://www.pprune.org/tech-log/53879...overspeed.html
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its franglais metroman pays not to think these things through too hard. full spd brks means full whatever the lever will give you at the time
if airbus said half brakes sure as **** someone will ask "is that half of half or...?"
i've only got 6000 bus hrs i admit but i've never had an a/p just wave its hands in the air and give up coz the manuevre or turb got too much for it
mmo and vls are indications only. not ideal in a line check but ffs you wont die if you touch one lets not be too precious about it
if airbus said half brakes sure as **** someone will ask "is that half of half or...?"
i've only got 6000 bus hrs i admit but i've never had an a/p just wave its hands in the air and give up coz the manuevre or turb got too much for it
mmo and vls are indications only. not ideal in a line check but ffs you wont die if you touch one lets not be too precious about it
Nunc est bibendum
mmo and vls are indications only. not ideal in a line check but ffs you wont die if you touch one lets not be too precious about it
