Flight envelope protection event involving an Airbus A320

[Ichiban]

Full report at:

Investigation: AO-2014-049 - Flight envelope protection event involving an Airbus A320, VH-VQY, near Mildura Airport, Vic on 12 March 2014 (http://www.atsb.gov.au/publications/investigation_reports/2014/aair/ao-2014-049.aspx)

On 12 March 2014, at about 0920 Eastern Daylight-savings Time, an Airbus A320 aircraft, registered VH-VQY, departed Melbourne, Victoria on a ferry flight to Darwin, Northern Territory, with a captain and first officer on board.
After about 5 minutes in the cruise at FL 360, the captain temporarily left the cockpit. When abeam Mildura, Victoria, the first officer received a clearance from air traffic control (ATC) to climb to FL 380.
Approaching FL 380, at about FL 373, the first officer observed the airspeed increase and the airspeed trend indicator approaching the maximum operating Mach number (MMO). He attempted to reduce the airspeed by selecting the speed back to M 0.76 however he observed the airspeed and the trend continue to increase. The first officer reduced the thrust to idle, which disconnected the autothrust, in an attempt to reduce the airspeed. He extended the speed brake and disconnected the autopilot to adjust the pitch attitude of the aircraft in an attempt to maintain the selected altitude.
When at about FL 383, the first officer re-engaged the autothrust, and returned the thrust levers to the climb detent. He applied forward pressure on the sidestick to lower the nose attitude of the aircraft in an attempt to recapture FL 380.
The aircraft then descended and the airspeed slowed below the VLS speed. The first officer then applied rearward pressure on the sidestick in an attempt to regain FL 380 and reduced the thrust levers towards idle but short of idle stop position. The application of back pressure increased the aircraft’s angle of attack. At the Alpha Protection speed, the Alpha Floor function activated.
This incident provides a reminder of flight crew of highly automated aircraft, to understand the implication of the intended and actual level of automation applied.

[outside limits]

Unbloodybelievable.
The result of this was that both pilots need to be at the controls for enroute level changes. This doesn't address the incompetence but merely confirms that only one pilot in the cockpit knows what he's doing.

[emeritus]

I find some of these incidents strange, speaking as an old pre glass/ fully automated pilot.

2+2 always equals 4 the same as cruise power for the applicable flt level always equals the applicable cruise speed.

If the ASI says otherwise then the ASI is lying. The only way I would be looking at idle thrust at high altitude is if I were wanting to descend.

All that is needed to fly at FL380 in fact is an altimeter, a thrust indicator and a manual of power settings.

Emeritus

[waren9]

emeritus makes a good point but these things arent usually as simple as they might be.

not defending the crew but

climbing in to a suddenly increasing headwind, some weight and not a lot between mmo and vls and perhaps an atmosphere different to isa all can conspire against a young airbus pilot

the report doesnt go that far, so who knows.

[Capn Bloggs]

Fascinating stuff.

I'm disappointed at the rabid condemnation that regularly occurs on Proone when one of these incidents occurs. I had a look a couple of days ago on the ATSB website and there are quite a number of incidents; good targets for sledgers but equally good learning material for those of us trying to better ourselves. So pull ya heads in and learn.

This incident provides a reminder of flight crew of highly automated aircraft, to understand the implication of the intended and actual level of automation applied.
And also a reminder that accurate handflying is still a critical skill and may be required at any instant.

What are the
He observed the TOGA LOCK display on the engine warning flight director

immediately scanned the primary flight director (PFD)
:confused:

Nowhere near enough detail in the report about the FCOM procedures for overspeed nor when it was changed. As per bluesky, maybe it's a French thing that a procedure you may have to do instantly from memory is not a Memory item. I know it's cool to have only a few memory items but...

Would also have been nice to have the trace of the N1 for those of us who don't understand what the Climb Detent does at various times, and AP status trace.

I don't understand why the aeroplane didn't level at FL380 the first time with the AP still engaged?

Want more reading on High Altitude Overspeeds? There's a 7-page thread on it in Tech Log:

http://www.pprune.org/tech-log/538793-reducing-thrust-cruise-overspeed.html

Another PPR
I'll bite! What's a PPR (other than Prior Permission required)? :}

[clunckdriver]

As one of the early Bus pilots in North America , this merely demonstrates the flawed logic behind much of the Airbus design philosophy, but don't try telling this to Mr. Ziegler unless you want to be in court till Hell freezes over, he is always right no matter what, this in spite of the industry finally waking up to the importance of high standards of hand flying, be it via cables, hydraulics, or FBW.

[Ned Gerblansky]

There is an old joke about the difference between an experienced Airbus pilot, and those of lesser experience and it goes like this:

An in-experienced Airbus pilot exclaims "What's it doing now?!!"
An experienced Airbus pilot calmly says "Oh, it's doing THAT again!"

IMHO the error here was that the F/O, assuming an autoflight malfunction, did not take full manual control, and got lost in the limbo that exists between partial autoflight and full control by the PF or the AP. "Mode mis-match" it was called in the early days.

An airmanship issue could be argued that, having experienced difficulty with what one thought the automation was doing, the climb could have been delayed and the aircraft returned to straight and level. My point is either YOU fly it or you let it fly you.

I remember once in the cruise at about F360, scanning around the displays, I happenned to catch both engines winding back (commanded by the autothrust) to idle. I immediately brought this to my F/O's attention and said words to the effect of "Hey, check this out!!"

We were in clear skies, no change of wind or temperature, no turbulence and both engines were running. I guarded the throttles, ready to push them forward of the climb detent, which overides autothrust. The airspeed decreased nearly to Vmin, when the engines roared back to climb power, stabilised @ the desired mach no and no further incident. It's an airbus - plastic heap of Euro****te.

Bottom line is for newbies on that thing-that-isn't-an aircraft, if it don't do what you want it to; 3 clicks! Auotpilot off, FD off, Autothrust off and then you're in a Cessna 150. Alpha prot and TOGA lock are the aeroplane trying to avoid a stall - and that can only be brought about by mis-handling, deliberate or not.

Hope this helps, cheers Ned.

[old rope]

The report doesn't mention when the PF actually retracted the speed brakes. Were they left extended until auto retract at Alpha Floor? Am aware of this scenario occurring previously with similar results.

Tough crowd this pprune thing, can't help but wonder how well some of the commentors would have handled this situation in the early days of their high performance jet careers.... FL380, a rather reduced flight envelope, alone on the flight deck with a PFD full of carnage. Not an easy place to be...

Leave the automatics in, let it overspeed, there will be considerably less paperwork.

[Capt Kremin]

I don't fly the 320 but am wondering if there is an issue with the autothrust response at light weights here.

I once did a ferry flight in a 330 where the autothrust was cycling between full thrust and idle as it attempted to hold the cruise speed at FL410. The aircraft was very light. Descending to 370 fixed the problem.

Perhaps there is a similar issue on the 320 as it seems like the autoflight system didn't cope very well in the initial parts of the incident.

[maggot]

Leave the automatics in, let it overspeed, there will be considerably less paperwork.

yeah, sure - do what you can to prevent/avoid the situation but has an aircraft ever crashed from a minor speed excursion in the cruise? no need to rush into things.

general comment.

also, in climb the engines are targeting N1 - engaging a speed mode through 'alt' or whatever can reduce the thrust without mixing things up (as ned says above), add speedbrake if needed.

[Mobi LAME]

You bloody Tech Crew! There was nothing wrong with the aircraft, other than a dunny flush CIDS problem, when we fly it out from the factory, it was about 30,000 flight hours ago though.

[LightItUp]

Cadet.....? :ugh:

[TurningFinalRWY36]

Can you please explain how a newly hired direct entry would have done any better in this situation. I fail to see how burning around in a twin piston at 8000ft compares to dealing with a complicated jet aircraft at FL380 at M0.8

[Mud Skipper]

I fail to see how burning around in a twin piston at 8000ft compares to dealing with a complicated jet aircraft at FL380 at M0.8

And "therein lies the problem" as they say.:rolleyes:

[Wally Mk2]

Always interesting reading when it comes to high Alt jet upset events.

'old rope' was correct to some degree, "leave the auto's etc' in" but having said that hind sight is always a wonderful thing but humans when presented with the abnormal/unusual/different often react or revert back to other ways of thinking despite current training etc,(Air-France A330, perfect Eg) IE reduce thrust, get some spoiler action happening (phew saved the overspeed)& then focus on not busting any ATC laws (going thru an Alt) this compounds the whole situation with all the time in the back of ones mind.....sh1t am in trouble now with the CP, you know 'just culture' & all that crap!!!.
The 'Bus' loves to hang the driver/s & it pays never to take yr eyes off the speedo for too long, in fact in any A/C obviously but with the 'Bus' the very soft auto-flt logic means it feels likes it's way behind the 8 ball just to keep the boguns comfy!:-)

Remember guys these fancy machines are designed by humans, fixed by humans & flown by humans & they are sadly still flying into the side of mountains in perfect mechanical condition so that means there is always gunna be cock-ups from the stick in the sand design stage all the way up to test pilots, how else do we find out errors whether that be human induced or design induced & learn from them?:-)

We ALL learn, this event is just another class-room day.

Wmk2

[Keg]

can't help but wonder how well some of the commentors would have handled this situation in the early days of their high performance jet careers.

In the 'early days' of my jet career I wouldn't have dreamed of climbing without the other pilot on the flight deck....... but perhaps that's just me. :eek: :ugh: I've done it just once in nearly 20 years in QF. I was in command two-ish years so perhaps 16+ years experience. Never again after that time. Realised after the first little bit of the climb that I was widening the risk margins significantly for nil significant benefit to me or others. :=

[maggotdriver]

Winter time and jet streams. SA is the biggie here, we have all had issues at times with Boeings and Airbus. To all the cynics, I have thousands of hours in both and they're both crap at anticipating the large value shear. We however are aware of it and can look at a sigwx chart. Reduce the Mach prior to or at the beginning of the climb not after it's almost too late. It depends on the size of the buffer pior to reaching buffet. The 738 is crap! Not sure about the 320.

On a separate note two things. I wonder how long before the mods shut this thread like the one into the Goldie and secondly, I hear this is the fourth occasion in the last twelve months they have had a TOGA LK or alpha prot issue. Can anyone confirm this as this is alarming if true?

[Wally Mk2]

'Maggy' I doubt this thread will last long as it is about the J word which is associated with the Q word both a protected species in here at times:)
I hope it doesn't get slammed shut though as these discussions can be beneficial to some.

I agree with yr analogy about reducing the Mach, I use the 'Superman' philosophy (up up & away!) as I tend to pull off a couple of points of Mach to achieve just that (better margins) & to use the current energy to zoom up & get there faster, I mean after all if it's due turb then why hang around at Crz Clb?

Wmk2

[Ned Gerblansky]

I find the whole incident fascinating, and avoidable. One of the great assets of a forum is the ability to share information and suggestions to avoid a repeat scenario. A couple of points from my dim dark past:

Unless the crew is supplemented, at some stage in a long sector a pilot will leave to go to the toilet. The pilot remaining will then be single pilot, obviously. To those who say that 2 pilots should be on the flight deck for a level change, I question what happens when ATS say "Due crossing traffic climb NOW to F360"? Do you reply "Unable due captain having a leak", and then accept the 90 degree turn? What does the captain think when they feel the aircraft change heading in that scenario? Personally I would cease "splashing the boots" and get back into the cockpit and ask "What were you thinking?!!"

If an F/O is checked to line, then they should be able to handle any situation when the captain is not present, from TCAS to level 3 warnings - if not then they should not have been checked to line. From past experience the limitations of the Airbus autopilots are not widely taught, but the microchips and technology date back to 1980. In those days your computer would have been a Commodore 64, TRS-80, or if you were flash a Sinclair Z-80! These same chips power Airbus A320s today, and the autopilots are woeful. If ATS gives you a speed on descent of, say, 320 knots - the autopilot will handle that plus or minus 20 kts!! Reportable speed violations!

Next, an SOP from a long-defunct airline. When a pilot leaves the flight-deck, a flight attendant comes in, if only to open the door to the pilot outside in the event of incapacitation. The F/A cannot obviously occupy a control seat, so stands or jump-seats. It's amazing how more conservative the solo-pilot will be with another pair of eyes on them, qualified or not.

Lastly, was this incident caused by the F/O trying changing level using V/S? That only works on descent, in climb you stall, or get close. If you are new to the toaster (not-really-an-aeroplane-but-it-does-toast-pretty-well) use open modes for climb and descent. If in "coffin corner" select an airspeed between the zippers, give yourself a margin, and remember that one of those zippers will kill you -especially T-tails!!- the other will generate paperwork. As a lazy man I choose neither - be a lazy pilot and let the aircraft look after NOW so you can concentrate on NEXT.

Cheers,

Ned

[Cost Index]

Great post Ned. Agreed.

I hope admin keep this open. I find these discussions invaluable

[Denied Justice]

This discussions might be invaluable - but only if there is something sensible said.


Comments such as "SA is the biggie here" and the "Superman philosophy" hardly contribute to a rational discussion about this.


I certainly was not there and do not work for this company, as are probably most of the posters, but the hindsight committee on this forum is clearly alive and well.

[Boomerang]

As a bus pilot I'm curious how the 737 handles an over speed with the A/P engaged?

It seems the me the Airbus logic of only providing increased elevator authority in 'Expedite Descent' mode to prevent an overspeed should also be provided anytime the speed is close to the barberpole in any descent mode, (maybe even climb, altitude capture logic etc permitting). The Airbus does not have an amber caution range for high speed like the 737, (again I do not know what the amber range on the 737 represents or it's effect on the AFCS, if any) rather, with the Airbus you are in the green or you are in the red. Over speed too much and only then will the A/P react (prior to this the A/T should have reduced, or the pilot intervened) In my view the Airbus managed modes are full of threats for newbies.

[FlexibleResponse]

The event was clearly the result of Mishandling of the primary controls during a normal encounter with changing wind conditions during climb.

The aircraft raw data in the Report shows the following.

The FO extended the speedbrakes and LEFT THEM EXTENDED extended for nearly 60 seconds until they were auto-retracted by the activation of Alpha Floor. The speedbrake lever eventually was selected to the retract position by the Captain on his return.

The FO selected the Thrust Levers to near idle (on the second occasion) just as the aircraft was entering (high) Alpha Protection. He did NOT select the Thrust Levers to TOGA in accordance with the FCOM procedure when Alpha Floor was activated. The Capt selected the throttles to Climb on his return.

The ATSB Report on the incident is woefully inadequate in addressing the primary and secondary causative issues and indicates a lack of understanding and thorough analysis.

There are very clear inadequate training issues to be addressed and they were not identified by the Report.

Good airmanship dictates that when using the speedbrakes it is advisable to always leave one's hand on the lever until they are retracted (except momentarily for other control selections) so as not to forget they are extended.

At high altitudes especially, speedbrakes should be the primary method used to prevent overspeed when excessive speed trends occur. Thrust reduction is not effective in the short term to stop an excessive speed trend close to Vmo and the engines take forever to spool up again from idle.

In case of actual overspeed, FCOM procedures should of course be followed... which normally includes Thrust Levers to Idle and Speedbrakes extend.

The FO exhibited classic symptoms of sensory overload...something that proper simulator training in high altidude speed excursions would easily address...

Alas I fear the message has being lost in the smoke and mirrors of the Auto Flight Modes understanding or non-understanding, usage or non-usage arguments.

[Popgun]

The FO exhibited classic symptoms of sensory overload...something that proper simulator training in high altidude speed excursions would easily address...

But that would require a well-resourced, well-mentored cadet program...which, of course, would cost money...

PG :ugh::ugh::ugh:

[Derfred]

Strongly disagree.

You can't teach this stuff in a Sim... sorry.

[maggot]

Unless the crew is supplemented, at some stage in a long sector a pilot will leave to go to the toilet. The pilot remaining will then be single pilot, obviously. To those who say that 2 pilots should be on the flight deck for a level change, I question what happens when ATS say "Due crossing traffic climb NOW to F360"? Do you reply "Unable due captain having a leak", and then accept the 90 degree turn? What does the captain think when they feel the aircraft change heading in that scenario? Personally I would cease "splashing the boots" and get back into the cockpit and ask "What were you thinking?!!"

I agree with most of your post, ned, but your hypothetical is obviously silly - of course you'd climb. I'd suggest its more about voluntarily entering that position vs needing to do it.

[Keg]

Due crossing traffic climb NOW to F360

Of course. Doing the climb single pilot in these circumstances is the 'least risk' option.

Let's be honest though, how often does this sort of clearance arise? I've had less than a handful in the last 19 years. It's not clear that this was the circumstances in this case.

Which brings me back to point 1. An understanding of 'least risk'. As an ex cadet, two years in the back seat of a 744 at least gave me some pretty good exposure to the demonstration of this before I then did F/O training.

We all make mistakes (as I did making a climb in much more benign circumstances) and it's important to learn from them in terms of the specifics. However unless we go back a step from the physical errors made and loom at the cultural and other non technical aspects of these sorts of events (which it doesn't appear the ATSB report delves into) then we're missing half of the lesson and to my mind probably the most critical part- the part that stops these things or similar from happening in the first instance.

[Popgun]

As an ex cadet, two years in the back seat of a 744 at least gave me some pretty good exposure to the demonstration of this before I then did F/O training.

And thats one of the main issues with this cadet program. They are in a control seat with virtually zero experience from day 1 in a lightning-paced, 4 sector, 12-hour shift environment that includes complex, high-workload airports. The learning curve is excessively steep and loaded at every stage with threats. The back seat of a 1 sector flight from ILS to ILS would be a much safer learning environment.

The guy in the left seat is finding himself single pilot on many occasions when the flight goes "off script". I think the Australian public deserves better than that...but unfortunately this program is more about industrial agendas than pilot shortages.

I hear this issue (cadet overload) is a regular occurrence and was a causal factor in an incident with a flight departing YBSU recently without any V Speeds in the box...

PG

[GA Driver]

FlexibleResponse
At high altitudes especially, speedbrakes should be the primary method used to prevent overspeed when excessive speed trends occur.

Thats a wind up right?? You wouldn't wanna do that in a heavy 321 or 320 for that matter.
The speed brakes retract at a slower rate at high speeds which makes getting rid of them even tricker if the whole thing is botched up.

Since this wee mishap, the SOP has changed to speed brakes 'as required'

And no need for the cadet bashing, it wasn't a cadet.

[Wally Mk2]

I wanna get in the Sim with Superman, he'll know what to do:E

Pretty much everything we do day-to-day is covered somewhere in the FCTM & other Doc's but sometimes there's nothing like experience & common sense to deal with an odd situation, both these traits are of a variable nature.

The Sim is the best place to practice this stuff with a grey bearded old salt of a Capt, not out on the line.

Wmk2

[maggot]

Thats a wind up right?? You wouldn't wanna do that in a heavy 321 or 320 for that matter.
The speed brakes retract at a slower rate at high speeds which makes getting rid of them even tricker if the whole thing is botched up.

Since this wee mishap, the SOP has changed to speed brakes 'as required'


or do whats in your FCOM SOPs not whats written on the internet.
My airbus SOP says keep the AP ON, Speedbrake.

Of course in a climb with the AT targeting a CLB N1 target, not speed, something must be done about the THR; ALT would put it into SPD mode and reduce it nicely, speedbrake as required.

[Keg]

And no need for the cadet bashing, it wasn't a cadet.

So even more important to discuss the cultural and non technical issues that contributed to the technical errors.

[Boomerang]

GA Driver: It's changed to speed brakes 'as required' because initially it said speed brakes 'full', which has the issue of slow retraction, but also the increase in VLS.

I know you'd never let it get to this, but just out of curiosity on descent (managed) you see a 20+kt speed trend vector, (high on slope, increasing tailwind, whatever the cause) you are already at target 320kt SPD +20kt (say 340 heading for 350kt Vmo. Are you saying you wouldn't use speed brake in the first instance? (Push speed / v/s zero ain't gonna cut it in time), would you be advocating exp desc, or manual flight before SPD brake?

[Capn Rex Havoc]

This type of event has been discussed in detail before.

Keeping the autopilot connected is important, because of the reduced longitudinal stability at high alt.

As an aside, exactly the same thing has happened before in my company on a big airbus over the himalayas. Same thing (tho they were in level flight). The skipper was also out of the flight deck on a comfort break. FO got into alpha prot and ended up descending a couple of thousand feet (triggering a TCAS RA on the way down).

Disconnect the AP at your peril.

[Bula]

Don't forget you can increase the A/P pitch authority by using the speed brake. You only need to crack it for the increased authority.

Boomerang, crack the speed brake and select a slower speed, say 300 initially, then use speed brake as required. The increased pitch authority will do the rest.... Maybe.. And if it doesn't who cares.

A320 tested Vd is 380 kts and M0.86. Accept the Overspeed. She won't fall apart.

[Alloyboobtube]

Its really important to keep Autopilot on , just wind speed back to about .75 and watch and wait.if it goes beyond the red so be it , the wings do not detach at the red line. Had one drift up to 360kts once no issues only a tech log entry and quick inspection. The speed brake drill was not in affect then.

[Boomerang]

I'm with you. Bula, I was just curious as to what GA Driver was trying to get at. At least in our company speed brake use is the FCOM method for handling an overspeed.

As Keg suggests, the key here is also all the things that lead up to the overspeed, threat/error management etc. That's harder to teach I guess than an FCOM procedure, certainly, it takes more time, and with a bit of time you get to observe such things on the line with an experienced pilot alongside you. If you are unlucky it happens on day 1, when the Captain has gone to the loo.(I have no idea what the situation or experience levels were on this incident)

I'm lucky I have 8 years and counting of observation on the magical mystery bus so far :-) and I'm still learning

[GA Driver]

Boomerang absolutely agree with your methodology with the set of circumstances you suggest i.e. on descent with tailwinds etc etc. But even that can depend on where in the descent you are.

I was responding more to flexible response's statement about 'especially at high altitude' and seeing the topic of this thread is climbing from 360-380 I strongly disagree that use of speed brakes at that altitude should be the primary method as was posted, thats all.

I guess it will come down to what you see at the time as to the crews reactions, but on the day to day ops I see, usually I don't have that flexibility of a blanket 'speed brake in the cruise' at the weights/altitudes I see.

I obviously have no clue on who operates what type in this thread, but I do know the 320 and particularly 321 is a lot different than the big 330 on this very issue. 330 didn't seem to have any troubles throwing out the anchor. Just some food for thought.

[Sue Ridgepipe]

Lastly, was this incident caused by the F/O trying changing level using V/S? That only works on descent, in climb you stall, or get close.Not always Ned. I often use VS in a climb if levelling off at low level after take-off to reduce the rate of climb, and also when changing from feet to metres and need to climb maybe only 100 or 200 feet VS is better to avoid the large thrust changes that come with using other modes.

I do agree though that most of the time VS is not a good idea for climbing, and certainly in this case it appears it was not the most appropriate mode.

[Ned Gerblansky]

Some gems of wisdom have appeared, in no particular order I'd like to:

hats off to Flexible Response for the airmanship issue of keeping your hand on the S/B lever until you are finished with it.

gold stars to GA driver and Bula about use of the S/B particularly at high altitude. That red zipper will jump on you faster than a Thai F/A raiding the food cart.

thumbs down to Der Fred - anything can be taught in the SIM - that's why they were invented. It's just that you need the willingness and the budget to do the training.

Cheers,

Ned

[Capn Bloggs]

Nothing has been mentioned here about

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.

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?

[Capn Rex Havoc]

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.

[Prince Niccolo M]

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... :mad: :ugh: :hmm:

[Keg]

Bring back Rob Lee and BASI.

[Capn Bloggs]

Alan Alan Alan as well (alas he's gone astray...)! :ok:

[amos2]

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? :sad::sad:

PS: Any bloke who can't climb 2000' without invoking Alpha Floor shouldn't be in the front seat of any aircraft! :(:(

[Ned Gerblansky]

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.

[nitpicker330]

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....:sad:

[KRUSTY 34]

Once upon a time pilots earned their pay by being pro-active! :sad:

[amos2]

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! :p:=

[nitpicker330]

Illusion-----I don't know a lot about amos2 but I do know he wasn't one of the heroes joining AN TN during the fiasco of 89' so I think you owe him an apology.

[amos2]

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! :D:D

[IcePack]

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.

[Metro man]

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).

[Oakape]

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/538793-reducing-thrust-cruise-overspeed.html

[waren9]

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

[Keg]

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

Smartest thing on this thread so far. :ok: