757 pilot had history of hairy landings [Archive]

Check Airman

4th Aug 2020, 06:27

If I read that right, the FO had amassed 60 landings over 80 sectors and still couldn’t figure it out? What’s the “standard” line training footprint across the sea?

Here, we do 25 or 15 hours on narrowbodies. Not sure about how the widebody guys do it. Granted, the FO in question had very low time, but the most I’ve ever heard of is someone new (first jet) getting 80ish hours of training. After that, the company usually cuts you off. This pilot got 285 hours.

Unfortunate that it didn’t work out for this person, but I suppose this is the system working as intended. I wish the person the best in future endeavours.

Banana Joe

4th Aug 2020, 08:16

40 sectors is the minimum for someone without experience.

Uplinker

4th Aug 2020, 09:27

A sad story.

I know of one person who passed the SIM but could not land the real 'plane, but in all my own type ratings, I have found the real 'plane in real weather much easier to handle and land than the SIM.

I can't help wondering how this F/O was taught how to land a 757 in the first place. I wonder even if they were even looking in the right places for the right cues as they flared.

I remember aeons ago when learning to fly Dash 8s; the TRI telling me to "follow him through" on the controls as he landed* This helped me tune my own technique and get the hang of it. Some people can respond to spoken instructions, others like me, learn much better by feeling or observing the correct actions.

Cannot follow through on an Airbus FBW, but this was a 757 with conventional yokes, so the same thing could have been done.

Another factor is the attitude of the training. If a person is struggling, what they need is a kindly, understanding soul to help them through their difficulty. If instead, they get a shouty person : "come on, concentrate, do it right!", they will likely not improve but get worse. Not saying that was the case here.

*Hello Stan :ok:

vilas

4th Aug 2020, 10:20

There's a small number they are in the wrong place. Considering the time, effort and money the airline spent on him they would be wanting to push him through with a slightest excuse but if they couldn't then it must be really unsafe. It's very rare that somebody gets rejected because one can't land. Atlas Air accident is a lesson not to ignore repeated poor performance.

stilton

4th Aug 2020, 10:21

That pitch up tendency after touchdown on the 757 is something you really have to watch out for, especially when combined with the less than linear, rather poor pitch control at low speeds

You have to make a conscious effort to carefully lower the nose or it can really thump down, this has caused serious airframe damage in the past

This was not a problem when using F25 however, perhaps the slightly higher VREF and lower drag contributed to greater pitch authority

It was approved at my operator and I used it all the time, runway length allowing

Oh and 238 passengers on a 752, that’s a bit tight !

jmmoric

4th Aug 2020, 10:47

It's very rare that somebody gets rejected because one can't land.......

But.... that's the "hardest" part of flying?

kenparry

4th Aug 2020, 15:34

Stilton:

238 occupants, not pax. 3 pilots, maybe 5 cabin crew, so about 230 pax. I have flown this type with 235 pax seats.

Johnny F@rt Pants

4th Aug 2020, 19:13

It is a 235 config, and is comfortable at that.

I see they have presumed the sex of the FO:=, which they have incorrect, not that it makes a jot of difference.

Here, we do 25 or 15 hours on narrowbodies 25 hours in the type of flying done here would have equates to a maximum of 10 sectors, and probably more like 6 or 8 sectors. Hours are irrelevant, it’s sectors that count. This FO had the minimum required (40 sectors), she was fortunate to work for an airline that really tried hard to help and gave her more training, however she was in that very small minority that just didn’t get it and there comes a point where that training has to cease. I know that she would have had some expert coaching, I know the trainers that would have been helping her, there would have been nothing wrong with that element I can assure you.

Banana Joe

4th Aug 2020, 19:26

Check Airman

4th Aug 2020, 19:34

Wow. Didn’t even know they could ask those things. Here, they can ask ethnicity, but it’s always optional.

How would anyone outside of HR know if her sex was part of the selection criteria?

Check Airman

4th Aug 2020, 19:37

Interesting to see that the FAA goes by hours and landings, while the UK goes by sectors. That seems more sensible than our system, but that’d certainly increase the time spent in training.

Banana Joe

4th Aug 2020, 19:52

Wow. Didn’t even know they could ask those things. Here, they can ask ethnicity, but it’s always optional.

How would anyone outside of HR know if her sex was part of the selection criteria?
Well, it's a trend in Europe at least. Look at easyJet and their Amy Johnson initiative. And if they had to make people redundant now simply based on LIFO, most of the pilots would be female. No, they just won't do that. They'd rather use a matrix and put in it various variables.

deltahotel

4th Aug 2020, 22:11

Meester proach

5th Aug 2020, 03:38

That’s a shame , but a third attempt at a line check, would have had me poised like a gunfighter , ready to take over .

Islandlad

5th Aug 2020, 04:06

Exactly what's required when flying out of these third world countries

.... according to information supplied by the operator, the Supervising Training Captain “had already failed the First Officer because of high pitch attitude before he was aware of the tail strike”.

I bet it was after that :E

Check Airman

5th Aug 2020, 06:20

The article said the captain should have intervened earlier. How’s one supposed to train or evaluate a student on landings if intervention is done at the first sign of trouble?

Papa_Golf

5th Aug 2020, 06:30

Given the history of the trainee pilot I agree with the article.

Once again she's making the same mistake, the one written in red all over her training file: why would you, the training captain, allow the safety of the passengers to be put in jeopardy? On the other hand I understand that's tough be the one terminating the trainee's career. Still, emotions should have little or no place in a flightdeck.

Check Airman

5th Aug 2020, 08:23

Fair point on the FO’s history, but I like to give the CA the benefit of the doubt. Dynamic phase of flight. The CA may have been flying with this person for the first time (admittedly a stretch after 285 hours).

Leslie

5th Aug 2020, 08:24

Initiating the flare at 100ft would be a clue that this was going to end badly. IIRC 6degrees at 48ft suggests the flare has been made and it is only because the TLs are still open that it didn’t fall out if the sky. The pressure playing on the trainee by the time they get to this stage would be so intense but with the final goal within touching distance they feel they are almost there...a bad place to be and falls upon the training management to make those hard calls. Tough time for all involved, not least the TC that could have and, in my opinion, should have intervened earlier. I wasn’t there and I understand how quickly these situations develop plus the added stress of The FO being in the last chance saloon but I like the gunslinger analogy above...there was form here so should not have been a surprise. Good learning for the rest of us.

nickp

5th Aug 2020, 10:02

I noted the reference to Base Training having been completed. I'm surprised that there seems to have been no reference to any problems at that stage in the training,

BDAttitude

5th Aug 2020, 11:13

That thread title didn't age well :}

Private jet

5th Aug 2020, 20:59

Manually landing an airliner or any high performance jet aircraft under normal conditions (99.5% of the time) is not difficult. It's a process, a procedure, it varies from type to type, but it's generically 50ft gently close the thrust levers, 30ft flare, aka pull back a bit, kick off any drift and wait. The M O for landing most airliners is flying them into the ground, along the runway with the right ROD of course. On the midsize bizjets I used to fly there was a little bit of scope for artistic flaring at the end but it really didn't make much difference. The REAL skill is presenting the aircraft to the runway at the right height, the right speed and the right heading in order to do the easy bit (landing!) but airlines discourage manual approaches now or insist on auto coupled to minimums. To be fair we did auto approaches, but we also did enough to know we didn't need to do them. I do know this, put most modern airline pilots in something like a Boeing 707, there would be carnage within a week. Yes the job has changed but the bar is much lower and so are the salaries...........

Banana Joe

5th Aug 2020, 21:35

What airliner requires to close the thrust lever at 50 ft?
All Boeing FCTMs say to start closing the thrust levers after the flare has begun to reach idle at touchdown.

Johnny F@rt Pants

5th Aug 2020, 21:43

Private jet

5th Aug 2020, 22:00

Oh here we go..........I guess you are unfamiliar with the term definition of the word "generic". Try and see the "big picture"

Check Airman

5th Aug 2020, 22:00

Private jet

5th Aug 2020, 22:02

Not for those surgeons with sufficient ability....

Check Airman

5th Aug 2020, 22:09

And only for those pilots of sufficient ability is landing a 757 easy.

Private jet

5th Aug 2020, 22:11

Do you have that ability? If so you should be agreeing with me...

Check Airman

5th Aug 2020, 22:16

To land a 757? I like to think I could do it if trained. Haven’t tried though.

Private jet

5th Aug 2020, 22:28

Well, ability will always be envied. There's an old wisdom about trying to help the drowning man and he will drown you to try and save himself. Time to revert to silent running. Goodnight.

icemanalgeria

6th Aug 2020, 01:05

I understand this exact situation as I made a line check as Captain with a older FO I had flown with in a previous company and who I’d recommended to his New company. The examiner being on the jump seat. It was 4 sector trip. It was very hard for me to take control but that’s what I did for his first two landing at 50’ pushing lots of thrust and lowering the pitch to recover the landing. We have to have a final gate that we must not pass where a safe recovery can me made. I feel sorry for the first officer, and also for the Captain who knew if he took the controls it was then end for the FO

RetiredBA/BY

6th Aug 2020, 08:48

Interesting thread. Heres my take:

The 757 is incredibly easy to land smoothly and accurately:

After a stable approach followed by the 50 feet call, count to three, ( 2 on a 76!) raise the nose to set the correct attitude, about 21/2 degrees, smoothly close close, retard, Thrust levers and jt rolls on beautifully, every time.

The FCTM is quite specific. “ Do NOT allow airplane attitude to increase after touchdown” (caused by spoiler lift, which I believe moves the c of p forward) Risk of tail strike with all the consequences of possible damage to the pressure bulkhead.

Failing a final line check is secondary to ensuring the absolute safety of the aircraft and all on board.

I also feel as an ex RAF CFS QFI and TC the training captain should have been ALMOST hands on to take control, or at least minimise incorrect control input, absolutely as soon as the limit of safety is approached, particularly with a trainee who has shown poor skills in earlier training, final line check or not.

The 757 is a truly delightful aeroplane and a pleasure to fly, and I have often said that if you cant land the 75 perhaps airline flying is not for you !

Back to my morning coffee!

blue up

6th Aug 2020, 09:34

18 years on the 757 and I only managed one landing I wasn't proud of (Windsheary day into Tenerife). 737-8 in comparison always seemed to land like a truck falling off a cliff edge. Horrible, horrible machine.

Had an ATPL recently in the Sim at our place who couldn't safely take off. THAT'S SCARY!

PilotLZ

6th Aug 2020, 10:19

Interesting what the underlying causes might have been. If the pilot started flaring at 100 or even 50, that speaks of a very severe misjudgement of height. Something I would be seriously looking into if faced with rectifying such a problem in someone is where they are looking during the final approach and flare. Some people look at the very far end of the runway which makes them flare high (but often still not as extremely high as 100 feet). Conversely, those who look straight below the nose risk either not flaring at all or doing it late enough to land quite hard. Same or worse goes for those who chase the FD bars without looking outside literally until flare. Also, leaving the AP on until 400 feet is not appropriate for someone with low experience and apparently poor technique. Late AP disconnection with no time to properly adjust to manual flight often results in dire landings among the beginners.

It would be interesting to scroll through the training file of someone like that. If the problem had been apparent for months before this occurrence, how exactly was it addressed? What remedial training was given? Was change of instructor considered? I have a feeling that there was some root cause which was never addressed.

Banana Joe

6th Aug 2020, 10:28

PilotLZ might be onto something. At the beginning I also used to have issues to judge my height over the runway when looking at the opposite end of the runway, but looking 3/4 down the runway works for me.

I think that a couple of simulator sessions with focus on landing might have given a different outcome to the whole story.

Airbubba

6th Aug 2020, 19:04

I am going to be straight with my question: was gender part of the selection criteria?

Shhh... you are supposed to ignore the elephant in the room. ;)

Another recent case of adjusted training standards to embrace a non-traditional hiring demographic with the PF in the Atlas 3591 crash:

Training Incompetency and Failures

6/27/11 - Resigned from CommutAir for failing DHC-8 initial
8/13/12 - Resigned from Air Wisconsin for failing CRJ initial
4/22/14 - Failed EMB-145 Oral at Trans State Airlines
5/11/14 - Failed EMB-145 Type Rating at Trans States Airlines
5/17 - Failed EMB-175 Upgrade Attempt at Mesa Airlines
5/17 - Nearly failed FO Requal after failing upgrade attempt at Mesa Airlines
7/27/17 - Failed B-767 Oral at Atlas Air
8/1/17 - Unsat Judgement/Situational Awareness during FBS-1 at Atlas Air
8/5/17 - Failed DBS-5 at Atlas Air
8/11/17 - Almost Failed FFSI-1 at Atlas Air
8/31/17 - "Regression of Situational Awareness" during FFSI-3 at Atlas Air
9/22/17 - Failed B-767 Type Rating for "Very Low Situational Awareness", incomplete procedures, and exceeding limitations at Atlas Air

Past Training Notes (directly quoted from the NTSB Docket)

Air Wisconsin CRJ Initial Failure - "They were conducting the emergency procedure cabin altitude ... where they are at FL350 or so, and he gives the students a cabin altitude message requiring an emergency descent to 10,000 feet" ... "Conrad then goes to descend the simulator. He was not sure of Conrad's background, but instead of descending on the autopilot, Conrad disengaged the autopilot and abruptly pitched down well below horizon. They got stick shaker and overspeed alert together. He was not sure if it was an extreme nose down, but remembered that it was abrupt input on the controls"
Mesa Airlines ERJ-175 Upgrade Failure (Instructor 1) - "He had previously failed simulator lesson 2 with different instructor, and he had requested a different instructor. She was conducting his retraining for lesson 2. She said his performance was a "train wreck" and he performed very poorly in this lesson. In the briefing room he did well, and explained things well. However, in the simulator and something he wasn't expecting happened he got extremely flustered and could not respond appropriately to the situation." ... "When asked about her comment in her notes about Conrad's "lack of understanding of how unsafe he was," she said he was making very frantic mistakes, lots and lots of mistakes, and did a lot of things wrong but did not recognize this was a problem. He thought he was a good pilot never had any problems and thought he should be a captain. he could not evaluate himself and see that he did not have the right stuff."
Mesa Airlines ERJ-175 Upgrade Failure (Instructor 2) - "He first met Conrad Aska during a recurrent checking event in March 2016. That session went ok and nothing stood out. He did have some trouble with the stall series. The problems were with his attitude control, and he had a hard time getting the airplane back to level flight" ... "He said when Conrad would make a mistake in training he had an excuse for everything"

Banana Joe

6th Aug 2020, 19:19

I've been called a troglodyte today in another forum for raising this point. Expect some incoming fire from some political correctness fanatics now:E

deltahotel

6th Aug 2020, 20:16

I’ve looked at the report and the remedial work is about what I’d expect any decent airline to give to a struggling student. Since I have no access to the recruiting system I can’t comment on their methods or preferences. S*** happens. Generally I’d put effort into trying to fix a single handling problem if the rest of the work is good - SOPs, CRM etc.

I can understand a TC letting it go as long as poss - no one wants to be the one to end a dream - but I can’t help feeling earlier intervention would have been the right thing to do.

I’m interested that there were two TCs on board. That would seem to put pressure on pressure, but it’s not my trainset. JFP seems to have a good insight into training methods at J2, certainly more then me.

For me, this is nothing to with pc - perhaps if a job offer doesn’t come your way, maybe that could be inferred. On the other hand, if you’re now working in freight then maybe the outcome is not so bad! From the outside looking in it seems that the airline chimes right in the way it does training business.

Best wishes to all

giggitygiggity

8th Aug 2020, 01:08

I am going to be straight with my question: was gender part of the selection criteria?
Jet2 has to be the company that asked me the highest number of questions concerning my gender, sexual orientation and ethnicity. And they are not the only UK carrier I've applied to in my life.

As an aside (kinda), a group of us started as cadets many years ago, straight on to the A320 with an excellent (training-wise) large Airbus operator in Europe. Everyone had their ups and downs with the landings, however only one of us was tough enough to ask to repeat base training as they had lost their confidence with their landings. It was of course the only woman in the group. Youthful me probably found that quite funny and would have sadly gossiped about it with the rest of the guys, but grown up me realises that myself, or many of the other men would have probably done the same if our machismo hadn't gotten in the way of our development.

We all made it through, but I can't think of any more accutely stressful time of my life - which would probably have been resolved with another six landings at a quiet European airport.

If I read that right, the FO had amassed 60 landings over 80 sectors and still couldn’t figure it out? What’s the “standard” line training footprint across the sea?

Here, we do 25 or 15 hours on narrowbodies. Not sure about how the widebody guys do it. Granted, the FO in question had very low time, but the most I’ve ever heard of is someone new (first jet) getting 80ish hours of training. After that, the company usually cuts you off. This pilot got 285 hours.

Unfortunate that it didn’t work out for this person, but I suppose this is the system working as intended. I wish the person the best in future endeavours.
285hrs is indeed a lot, but the 757 was probably used for medium-haul work mostly (eg fewer sectors than city hopping round the US). Jet2 does a lot of sunny island work so there will have certainly been fields with little more than an NDB and a guy that likes to dress up as an air traffic controller.

These guys that enter airlines as 'cadets' over here might join with approx 150hrs. They might not have spoken to European ATC during their whole training period. The learning curve is tricky and steep. I assume that when you train someone for 25hrs, most of them will have at the minimum trained in the US under FAA regs, but more than likely have flown other commercial ops or have 1500hrs of ATC comms under their belt. Of course I'm just highlighting ATC specifically but it must take a little more refinement over here. Without getting into a debate over the merits of one system over another, largely, safety doesn't seem to be compromised by this approach at all. This is a rare incident that isn't alien to many experienced pilots who were never 'cadets'. After all, Delta managed to smash a 757 into the Azores (http://avherald.com/h?article=4cbb7c2a&opt=0) in equally CAVOK conditions.

The thing that worries me most about this is that through the control wheel; the captain knew exactly what inputs the FO was applying and that they couldn't react well enough to avoid the paperwork. It's trickier on the Airbus but surely on the Boeing, it's inherent?

Ollie Onion

8th Aug 2020, 02:34

That is not an unreasonable amount of hours considering he had reached the maximum retraining sectors being 'up to 3 x the initial training sectors'. I read this to mean that by the time he was on his 3rd line check he had used 120 training sectors which would mean an average flight time of just over 2 hours. That would make sense as well that after 120 sectors he had performed 60 landings. The fact that 11 of those landings resulted in a take over by the training captain speaks volumes. I spent years as a trainer of new pilots onto the A320/21 and could honestly say I had to physically take over less than 11 times in my whole training career. It is a big deal to be having to take over 15% of a single trainees landings. Some people just can't be trained, I had a ppl student handed to me once, he had 120 hours total and hadn't gone solo as he couldn't land. I did about 20 hours of circuits with him and 80% of the time he would do barely passable landings with the other 20% being down right dangerous. I suggested he take up golf, I talked to the CFI and said I had tried everything I could, the student went off to Florida and came back with a PPL, I suggested to the CFI it was a bad idea to rent aircraft to him, I was over ruled and off he went with two friends on a flight. Next thing we got was a phone call from Cranfields TWR to say that this guy had just bounced on landing in the 172, dinged the prop and veered off the runway ending up in a smoking wreck on the grass, thankfully everyone walked away. It can be the hardest thing to do, but sometimes people just don't have the skills to fly an aeroplane and it is only fair to tell them that.

Uplinker

10th Aug 2020, 09:51

I would be interested to know more about your C172 student not being able to land. Were you able to work out where he was going wrong? - was it where he was looking during the flare, lack of hand-eye coordination, lack of SA in three dimensional space etc?

You sometimes see car drivers going along the road with the wipers on, even though it is not raining at all - particularly the rear wiper. Or the fog lights on in clear conditions, or high beam on, blinding oncoming drivers. Or in the middle lane with no other cars around. And some drivers cannot plot their car in 2d space so they struggle to manoeuvre it in parking lots etc. So they are able to start the engine and drive along the road without accidents, but otherwise seem oblivious of where the car is in space and what the car systems are doing.

There must be some sort of perception gap that some have, or perhaps it is information overload? Maybe this is what is happening to a very small percentage of pilots who cannot land?

ohnutsiforgot

26th Aug 2020, 18:16

I am a one-eyed pilot, multiengine instrument rated, several thousand hours. I did have a fair amount of trouble with flare height until I developed an alternative method over a period of months, which was to look out the side window and judge closing rate as a matter of timing.. 5-4-3-2-1 . However my instructor would joke that what I really did was point the nose at the numbers and fiddle with the glove box door for 20 seconds or so. One thing that I did accomplish was adherence to glide slope and other instrument procedures, as I became more confident in the IFR environment than VFR.
FYI to get a license with one eye you need a medical flight test with a FAA medical examiner resulting in a waiver..

B2N2

27th Aug 2020, 00:00

I have trained students for their PPL with vision in only one eye and I have flown with a Capt in a large Transport category aircraft that had the same.
Apart from the obvious you couldn’t tell the difference in skill level.
As far as the student who pranged the C172....i say it somewhat jokingly as I only have my own experience and anecdotal snippets from others: 3 out of a 100 are gifted natural pilots. Combination of spatial and mechanical intuition and spades of common sense.
They’re the lucky ones and when encountered should be encouraged to pursue a career in aviation.
On the flip side of that coin we the 3% that cannot be taught how to be a safe and proficient skilled pilot. They lack the correct combination of before mentioned traits.
They vary from 250 hr PPL’s to the quadruple failure of every exam to the never solo which are obviously the most extreme cases.
I’ve personally flown with an individual who would return after a 6-9 month hiatus and 100-150 hrs missing out of his logbooks.
Every instructor we had (5-6?)tried and tried and tried again and eventually we ran out of instructors and that’s when he left.
We thought he had in excess of 250-300 hrs dual instruction with no solo.

The other 94%? They have to work hard at achieving their goals in aviation like I did.

Pugilistic Animus

28th Aug 2020, 01:13

To land a 757? I like to think I could do it if trained. Haven’t tried though.

You most certainly can... easy

I wish I could say the same thing about Airbus but I also do believe that I can fly her with training... With No training I would call the radio and have them provide me with instructions from an Airbus pilot

Please eat the chicken not the fish :}

Uplinker

28th Aug 2020, 09:39

An Airbus FBW flies manually just the same as any other modern jet. There is no difference in how the controls work in manual flight apart from the side-stick, but that is really easy.

Thrust levers, gear, flaps, speed brake, ground spoilers, wheel brakes, reversers, taxiing, all have the same controls and work the same as any other modern jet, with a couple of minor differences. You still push the thrust levers forward for more thrust, pull them back for less. You pull the side-stick back to pitch up, push forward to pitch down. You move the side-stick sideways to roll. The speed-brake lever is clicked out in length to arm the ground spoilers and there are push buttons instead of a rotary switch for auto-brake. Rudder pedals and wheel brakes and steering tillers are the same.

You don't have to trim anything. It stays in the attitude you put it. The trick is to use the stick to set the attitude you want, then let the stick centralise. The aircraft will then stay there, in that attitude (barring large turbulence upsets). (The FBW will modify side-stick inputs, and limit extreme ones, but in normal flying to approach and land, this will not be evident).

If presented with an Airbus FBW in manual, you would have very little trouble flying it and landing it :ok:

Check Airman

28th Aug 2020, 13:02

...and you’d have a great deal of fun doing so

172_driver

28th Aug 2020, 17:58

Check Airman

28th Aug 2020, 20:35

To anyone who's spent a length of time on an Airbus with auto trim, then converting back to a type where you have to trim yourself; do you get rusty or is it still second nature?

(i am still not sure if i would be on the pedals going back to a C172)

It took me a while to get used to trimming again. In the sim at first, then again in the airplane. Quite frustrating, to be fighting with the plane until you figure out why it won’t stay put.

stilton

29th Aug 2020, 08:27

Uplinker

29th Aug 2020, 08:47

To anyone who's spent a length of time on an Airbus with auto trim, then converting back to a type where you have to trim yourself; do you get rusty or is it still second nature?.....

I went from 13 years on Airbus A320/321/330, onto Boeing 737-300/400 (tel:737-300/400) - some of which were round dials :eek: (And a year later, back onto A330, thankfully)

I was delighted to find that my trimming, (learned from 5 previous years to the 13, on non FBW aircraft), came back immediately and instinctively without conscious thought. Not always 100% accurate, but it was 95% there.

@ stilton; No an Airbus FBW in manual flies just the same as a Boeing in manual, from a controls point of view. You push the thrust levers forward for more thrust, pull back for less thrust*. You push the side-stick forward to pitch down, pull back to pitch up. Roll is very slightly different because you push the side-stick sideways instead of rotating the yoke like a steering wheel. But the side-stick takes about 2 minutes to get the hang of. You don't have to trim anything on the FBW so it is easier. If you were transported from manually flying a Boeing to manually flying an Airbus FBW, you could totally fly it, and land it. It is easy.

*( Boeing thrust levers do not move in manual).

Check Airman

29th Aug 2020, 08:48

stilton I think Uplinker’s main point was that you don’t really think about it after a while. It comes pretty naturally. If you can’t fly a 737, you won’t be able to fly an A320.

At least when I’m flying, I don’t think in terms of what’s written in the book (g-load and roll rate). I don’t think anyone does. You just move the controls to the attitude and thrust that you want. I’ll concede that disengaging auto thrust can be more difficult that it needed to be, but once it’s off, it’s completely intuitive- push for loud, pull for quiet.

edit
It seems we posted at the same time Uplinker

nonsense

29th Aug 2020, 16:08

I am a one-eyed pilot, multiengine instrument rated, several thousand hours. I did have a fair amount of trouble with flare height until I developed an alternative method over a period of months...
In my late twenties, I was recently blind in my dominant eye due to a cataract when I was learning to hang glide. We were learning by gliding down a grass slope to a smooth sand beach and with no stereopsis my flares varied from dropping a good two metres to the ground to the occasion when I ran the crossbar into the sand without flaring.

vilas

29th Aug 2020, 16:48

I don’t doubt it but it’s just not correct to say that Airbus FBW flies manually just like any other modern jet
From not needing to trim, an auto thrust system that does not move the throttles to numerous protections and hard limits just to name a few there are significant differences to consider
I would differ slightly from Uplinker. It's not theoretically but practically also there is a difference. Airbus is flight path stable Boeing is speed stable. That means the aircraft behavior is not same with thrust and speed changes. Boeing 737 nose will pitch up or down but Airbus will maintain the flight path. That's why in 737 with autothrottle/AP it's either auto/auto or manual/manual. It was same in airbus non FBW but in AB FBW ATHR can remain on. In Boeing when you make pitch change you need to hold the new attitude till it is trimmed off or the nose will go back to previous attitude. Not so in AB FBW you make pitch change and return the stick to neutral or rather make a pitch change and leave the stick it's spring loaded to go back to neutral. In airbus when stick is out of neutral you are asking the computer to change pitch or bank. So if you are happy with your PFD you leave the stick alone. I have seen some trainees both abinitio and experienced initially creating their own instablity. Airbus is not difficult it's easy but different. Take missed approach 737 as you change the attitude aircraft itself will sharply pitch up and you may have to push forward then trim. Stab trim is not that simple. Unlike elevator trim tab which changes the neutral position of the yoke stab trim doesn't and you need to move back after trimming. Rostov on Don crash happened because the stick was held forward and prolonged trim was applied putting the aircraft in steep dive. In AB Aircraft will resist any change that is not commanded from side stick. So if pilot doesn't pull up it pitches 8 or 9 degrees. So you can pitch up all the way to 15° and leave the stick it will stay there. It's easy to switch to Airbus but an out and out CPL to command A320 pilot changing to 737 will have to rediscover basic skills of holding speed or altitude and trim. Because when you reduce thrust in AB nose doesn't drop nor does it come up with increase in thrust also there's no tactile feed back in the stick. Airbus is ideal for 200hrs guys to settle down to Airline flying. Even a less gifted can manage as it doesn't demand high standards of psychomotor skills.

anotheruser

29th Aug 2020, 17:00

AFAIK even the B777/787 has autotrim for thrust and configuration changes. Even the speed stability is artificial: Basically the control laws are the same as on the Airbus, with a function that chases airspeed put on top if it? Is it true that for speed changes you don't have to actually trim, but only briefly hit the trim switch in the correct direction and then it will trim automatically for the current speed?

I've always wondered what autotrim is good for. I mean, trimming is not that difficult, is it? You do it with your thumb, instinctively, mostly subconsciously. But it gives you a feeling for your airplane, how it naturally reacts to thrust and configuration changes etc. Through everyday practise, that knowledge will be more than just learned and trained, it will become engraved into your mind and you will be able to apply it without actually having to remember and think about it. There have been occurences in which pilots brought a crippled airplane back under control by lowering gear, using thrust, extending flaps etc. They did that intuitively because they knew how their plane would react to this. Would pilots that never trim their airplanes outside the sim be able to do that?

vilas

29th Aug 2020, 17:13

I've always wondered what autotrim is good for. I mean, trimming is not that difficult, is it? You do it with your thumb, instinctively, mostly subconsciously. As far as Airbus FBW is concerned it's not a question of easy or difficult but auto trim is essential design philosophy. It's not even the trim which comes into picture later it's the control which is held in position as commanded by the pilot through an integrater. Then the trim takes over. Airbus is for automated flights.

spanner the cat

29th Aug 2020, 22:31

The 777 trims for a reference speed, rather than a nose attitude. The trim isn't automatic, it has to be adjusted manually if the speed is changed. The system does compensate for thrust changes.

vilas

30th Aug 2020, 08:10

The 777 trims for a reference speed, rather than a nose attitude. The trim isn't automatic, it has to be adjusted manually if the speed is changed. The system does compensate for thrust changes.
Can you explain how does it compensate for thrust changes. In speed stable system if thrust is increased and if the flight path is maintained i.e. if the nose doesn't come up speed will increase. Similarly if the thrust is decreased if the nose doesn't drop speed will decrease. That's what happens in Airbus. What happens in 777?

Uplinker

30th Aug 2020, 09:38

I've always wondered what autotrim is good for. I mean, trimming is not that difficult, is it? You do it with your thumb, instinctively, mostly subconsciously. But it gives you a feeling for your airplane, how it naturally reacts to thrust and configuration changes etc. Through everyday practise, that knowledge will be more than just learned and trained, it will become engraved into your mind and you will be able to apply it without actually having to remember and think about it. There have been occurences in which pilots brought a crippled airplane back under control by lowering gear, using thrust, extending flaps etc. They did that intuitively because they knew how their plane would react to this. Would pilots that never trim their airplanes outside the sim be able to do that?

Fair points.

With my engineer's hat on though, since my distant C152 days I personally have always thought that the need to trim aircraft for speed ought to be designed out, (and ditto the pitch-power couple).

If, owing to a quirk of physics, our cars veered to the right with increasing speed, and to the left with decreasing speed, we would all get used to trimming them to keep straight, but it is so much nicer not having to do that and having a neutral steering wheel at all speeds.

Likewise, the Airbus FBW is really lovely to fly without having to trim all the time. I have passed 7 commercial type ratings so far, 5 that needed trimming, 2 that have auto trim. I much prefer those with auto trim !

nonsense

30th Aug 2020, 10:37

If, owing to a quirk of physics, our cars veered to the right with increasing speed, and to the left with decreasing speed...

That is exactly how a motorcycle and sidecar configured for the right side of the road behaves.

The faster you go, the more the sidecar drags you towards the near side of the road.
Under acceleration the sidecar tries to make you spear off the road.
Under brakes the sidecar tries to steer you into oncoming traffic.

To mitigate these effects, the bike is leant slightly away from the sidecar and the sidecar wheel is toed in significantly towards the bike, but this only helps,it certainly doesn't come anywhere near eliminating the joys of riding a sidecar.

And now your comments have me wondering whether it would be possible to dynamically adjust these "trim" conditions at least for different speeds.
Or I could just keep a safe distance from my friend's sidecar. My inner engineer is finding it difficult to resist getting involved, even as the bit of my brain that tried to ride one 39 years ago is howling in protest.

Uplinker

30th Aug 2020, 10:40

Brilliant ! :D :ok:

Fursty Ferret

30th Aug 2020, 12:48

Can you explain how does it compensate for thrust changes.

Two different effects with thrust changes:

* Pitch/power couple is almost entirely removed through software on a fly-by-wire aircraft.
* The 777/787 will pitch to maintain airspeed with a power change - add power, pitch will gradually increase to maintain the trimmed speed and vice-versa. An Airbus (with plain old C* law) will maintain flight path at the expense of speed until another limit in the flight path envelope is reached.

Personally I prefer the stability of the Airbus - on a gusty day with significant speed changes the flight path on approach tends to be nailed. Speed changes on a Boeing result in flight path changes.

vilas

30th Aug 2020, 15:44

Personally I prefer the stability of the Airbus - on a gusty day with significant speed changes the flight path on approach tends to be nailed. Speed changes on a Boeing result in flight path changes. I was writing on another thread about runway excursions in India. They are exclusively happening in 737 800. Although a good pilot is expected to handle any aircaft safely and within it's limits but those who are borderline not so adept appear to have problem maintaining the flight path lower side of approach after AP disconnection. They are crossing threshold between 100 and 150ft. speed +10 which doesn't appear bad but adds to landing distance, tailwind and prolonged flare resulting in overruns. Actually there are more A320s in India than 737s but they don't seem to have problem. Basic induction into both Aircaft is from the same common stock 250hrs CPL to start with then into command in due course.

Vessbot

30th Aug 2020, 16:36

spanner the cat

30th Aug 2020, 20:41

Can you explain how does it compensate for thrust changes. In speed stable system if thrust is increased and if the flight path is maintained i.e. if the nose doesn't come up speed will increase. Similarly if the thrust is decreased if the nose doesn't drop speed will decrease. That's what happens in Airbus. What happens in 777?

It's FBW. On the 737, if the thrust changes, the pitch/thrust couple is affected and a pitch input is required to maintain the flightpath. Any sustained pitch force will need to be trimmed out. The FBW on the 777 compensates for the pitch/thrust couple when the thrust changes. A trim change isn't needed because the FBW deals with the control force that would otherwise be required. When climbing, flying level or descending at a constant speed, assuming the aircraft is trimmed to the reference speed, there will be no control force to hold irrespective of thrust. If the reference speed changes, it will produce a control load which will need to be trimmed out. It is easier to use in practice than a paper explanation would suggest.

Banana Joe

30th Aug 2020, 23:09

My basic understanding of Boeing's FBW is that you don't touch the trim switches unless you need to change your airspeed.

CaptainMongo

31st Aug 2020, 22:31

The article said the captain should have intervened earlier. How’s one supposed to train or evaluate a student on landings if intervention is done at the first sign of trouble?

When training a new Line Check Airman I have a :45 minute brief I give called, “Verbally Managing the Landing.” (A319/320 - when training new Bus pilots I give a trainee version of this brief to them. This will familiarize them with the commands I will state in the landing phase and their expected appropriate response)

50’ AGL is where the start point of the brief and the selection of reverse is the end point. I identify gates, trainee action or inaction, verbal check airman commands (One - two words, easily said, easily understood), trainee response correct or incorrect and then further check airman verbal commands or, most likely, take over. Anticipation underpins all. (Obviously with no yoke, there’s no tactile nor visual feedback, that’s tough for a new check airman, one has to think about the landing phase differently when teaching IMHO)

You are correct you don’t have to intervene “at the first sign of trouble.” (Unless late in the landing phase) But I have found in almost all cases you should intervene at the second sign of trouble.

my 2¢.

PilotLZ

31st Aug 2020, 23:07

There's actually a silver lining to the lack of connection between the controls on both sides of an Airbus. It is that, unless they hear "DUAL INPUT" (or "I have control" if things go south far enough), the trainees can be totally certain that it was them and only them at the controls all the way through. In this way, it's a bit more clear-cut what works and what doesn't. In an aircraft with proper dual controls, some instructors may do subtle interventions on their side without later explaining that to the trainee - and, hence, the trainee can be left with a somewhat flawed impression of what needs to be done because he doesn't factor in that subtle, unmentioned input from the instructor.

That's the glass-half-full viewpoint though. The glass-half-empty one is that teaching and intervention indeed become more difficult and are well worth some dedicated discussion during LTC/TRI training (and, if you ask me, during every Airbus pilot training as part of the pilot incapacitation topic). The standard rules for taking over in the event of suspected incapacitation are not always safe enough close to the ground as you might not have the time to wait for a response to two consecutive deviation callouts. Conversely, if you always take control as soon as anything deviates from normal, that may be detrimental to the trainee's learning. It can be a tough call - and one that only comes with experience.

misd-agin

1st Sep 2020, 02:14

Personally I prefer the stability of the Airbus - on a gusty day with significant speed changes the flight path on approach tends to be nailed. Speed changes on a Boeing result in flight path changes.
Both concepts work but the Airbus is steadier. Point and let go... auto thrust off to stop the ridiculous power up, power back, power up, power back....ad nauseum, and the plane just tracks towards the aimpoint even in gusty winds.

stilton

1st Sep 2020, 11:13

So essentially Airbus FBW aircraft fly like any other

Airbus FBW aircraft

FlightDetent

1st Sep 2020, 12:32

So essentially Airbus FBW aircraft fly like any other

Airbus FBW aircraft :}

But then, after all, it will fool a human exactly the same as the 757 discussed above: https://assets.publishing.service.gov.uk/media/5422f3ca40f0b613460004f5/Airbus_A320__G-DHJZ_12-08.pdf
“THE FLARE WAS RATHER LATE THERE……..BUT THEN I SHOULD HAVE TAKEN OVER”.

vilas

2nd Sep 2020, 05:43

vilas

2nd Sep 2020, 07:53

But then, after all, it will fool a human exactly the same as the 757 discussed above:
Let's accept that the wonderful Airbus has an Achilles's heel in training a specially ungifted trainee about flare perception. So if trainer keeps flaring then trainee doesn't learn and if he doesn't then that can become the last landing before major maintenance. Also fracture of his disc is the least exciting thing a passenger is looking forward to. So since he has very poor judgement some safe guards have to be in place. He should not be executing the flare if the AC is not correctly placed with proper ROD at least from last 100ft. Any corrections required should be done by the trainer and then hand over for flare and landing. The second safe guard is at twenty feet RA call. Somebody needs to flare if not the trainee then the trainer himself. A small backward movement of the stick even without take over button and release will break the descent and touchdown anything around 400ft/mt. should be OK(no choice). Last every body doesn't have to be a pilot. May be the world is missing a genius in another field.

Uplinker

2nd Sep 2020, 08:47

Both concepts work but the Airbus is steadier. Point and let go... auto thrust off to stop the ridiculous power up, power back, power up, power back....ad nauseum, and the plane just tracks towards the aimpoint even in gusty winds.
(my bold)
Not sure what you mean here. With auto-thrust off you still follow the magenta speed bug right?.......which on approach is indicating ground speed mini.......which reacts to wind gusts.

So if the auto-thrust is going up and down 'ad nauseam' to follow the bug speed, then so should you be if you use manual thrust.

Boeing has a different way of calculating the approach speed, and you shouldn't substitute the Boeing method in the Airbus.

If you ignore Airbus ground speed mini you could end up in a very sticky situation.

EI_DVM

2nd Sep 2020, 15:54

Auto thrust off? In Gusty winds? That's not what airbus wants.

Not what Airbus wants but much smoother controls and manual thrust does a much nicer job in gusty conditions than the A/THR does. A/T works well in certain situations, but find it really can't compete with manual control on gusty, sheery days. It can get out of sync with the gusts and start an almost PIO type inputs. Much simpler to just fly it manually.

And also fully in compliance with Airbus' golden rules and principals of "If it's not doing what you want take control", and "use the appropriate level of automation for the task at hand".

vilas

2nd Sep 2020, 16:17

And also fully in compliance with Airbus' golden rules and principals of "If it's not doing what you want take control", and "use the appropriate level of automation for the task at hand"
You find problem with ATHR or the GSmini itself?

Bus Driver Man

3rd Sep 2020, 00:27

(my bold)
Not sure what you mean here. With auto-thrust off you still follow the magenta speed bug right?.......which on approach is indicating ground speed mini.......which reacts to wind gusts.

Yes, but GS Mini minimises the need for big thrust changes.
A positive gust increases your IAS, but the Vapp target increases as well. Only a small thrust increase should be required to compensate for the extra headwind.
A negative gust decreases your IAS, but the Vapp target decreases as well.

I think that misd-agin is referring to the A/THR overcorrecting in gusty conditions. Which it does. With the risk of reducing or adding too much power just before or during the flare.

Bus Driver Man

3rd Sep 2020, 00:39

Auto thrust off? In Gusty winds? That's not what airbus wants.
Airbus states that A/THR should be used, not shall.
They also state that the A/THR should be disconnected in case of unsatisfactory performance. Chasing the speed or overcorrecting can be seen as unsatisfactory performance. It would be the case for a trainee or a pilot being checked, so why wouldn’t it apply to the automation?

Everyone has their preference, and I agree that it’s easier to land without the A/THR making excessive thrust changes.

Fursty Ferret

3rd Sep 2020, 08:48

My experience is that GS-mini more or less eliminates “hunting” by the auto thrust in gusty conditions. I used to fly regularly without auto thrust at my previous operator and I’m embarrassed to say that it usually did a better job than me. I think I’ve flown one approach without auto thrust in the last eight years, and that was only because it was decided that VLS-5 was its new favourite speed, in an A321 at max landing weight and conf 3.

The 787 auto thrust, on approach, is excellent in my opinion. It obviously biases speeds above vref, but in general is completely reliable and unobtrusive. The exception is on intermediate approach when it frequently seems to forget that it’s responsible for the speed control during level-off, even with the speed trend arrow going well south of the bugged speed.

Uplinker

3rd Sep 2020, 08:51

Yes, but GS Mini minimises the need for big thrust changes.
A positive gust increases your IAS, but the Vapp target increases as well. Only a small thrust increase should be required to compensate for the extra headwind.
A negative gust decreases your IAS, but the Vapp target decreases as well.

I think that misd-agin is referring to the A/THR overcorrecting in gusty conditions. Which it does. With the risk of reducing or adding too much power just before or during the flare.

I must have been lucky then because in 13 years of flying A320/321 and A330, I don't remember ever seeing the auto-thrust overreact; it follows the speed bug. (I have seen it very busy on A320/321 and also had it under-react on A330). And I have landed in extremely gusty conditions seconds away from going around on several occasions because I had almost run out of roll authority.

The point of groundspeed mini is that it maintains the energy of the aircraft. If the headwind blows harder, the engines push harder, which maintains the energy, (and the groundspeed). This is completely opposite to a Boeing, which maintains the IAS, and would reduce thrust with a headwind gust. But one should not apply one type's SOP in the other.

I am very wary of pilots who pull for speed or use manual thrust to override Airbus ground speed mini. (Not saying you do).

champair79

3rd Sep 2020, 10:49

I am very wary of pilots who pull for speed or use manual thrust to override Airbus ground speed mini. (Not saying you do).

Agreed. Often it is due to a lack of understanding of the system. A quick point at the groundspeed provides comfort even if the speedtape looks a bit wrong.

There should never be any need to speed intervene unless GS-mini is getting towards the flap overspeed limit (even then, briefly pull speed and go back to managed speed as the wind starts to drop off as you get closer to the ground). Providing your IFLD permits it, these gusty sorts of days are great for flap 3. It gives you a few extra knots on the flap limiting speed, helps the aircraft settle onto the runway and gives you more performance in the go around.

champ

vilas

3rd Sep 2020, 14:16

There should never be any need to speed intervene unless GS-mini is getting towards the flap overspeed limit (even then, briefly pull speed and go back to managed speed as the wind starts to drop off as you get closer to the ground). Providing your IFLD permits it, these gusty sorts of days are great for flap 3. It gives you a few extra knots on the flap limiting speed, helps the aircraft settle onto the runway and gives you more performance in the go around
Agreed with the first statement. There's no need to even momentarily go select because the GS mini limitation on IAS with full flap is VFE-5 and as the speed trend goes to VFE ATHR will head towards idle. Even select speed can't do more GSmini IAS limits are VFE-5 in full and VFENext for other configurations. So in Flap3 the IAS limit is 177kts. i.e. 8kts less than VFE of 185kts.
and in Flaps full it is 5kts from VFE. but aircaft will find it easier to accelerate in Flap3 than Flap full. So not much advantage. Besides in turbulence for better handling Air bus recommends Flaps Full not Flap3 unless windsheer is expected.

CaptainMongo

3rd Sep 2020, 22:42

GSmini IAS limits are VFE-5 in full and VFENext for other configurations. So in Flap3 the IAS limit is 177kts. i.e. 8kts less than VFE of 185kts.
and in Flaps full it is 5kts from VFE. ...

Hey Vilas,

This GSmini limitation, “and VFE Next for other configurations.” isn't in our manual. (we don’t use the FCOM) can you post the excerpt of that so I can take it back to our folks?

thanks,

vilas

4th Sep 2020, 04:03

Hey Vilas,
This GSmini limitation, “and VFE Next for other configurations.” isn't in our manual. (we don’t use the FCOM) can you post the excerpt of that so I can take it back to our folks?
thanks,
Hi

https://cimg9.ibsrv.net/gimg/pprune.org-vbulletin/1920x1080/screenshot_20200904_092735_2_cb0541fdc9fd2fdbe4a6eca4096b7c6 e4ecb44de.png

Bus Driver Man

5th Sep 2020, 01:05

I must have been lucky then because in 13 years of flying A320/321 and A330, I don't remember ever seeing the auto-thrust overreact; it follows the speed bug. (I have seen it very busy on A320/321 and also had it under-react on A330). And I have landed in extremely gusty conditions seconds away from going around on several occasions because I had almost run out of roll authority.

I’m not sure if it’s due to the IAE engines, or if it’s a software modification on newer A320s, but I’ve noticed an occasional late A/THR reaction followed by an overcompensation. E.g idle thrust kept until manoeuvring speed - 5kts or Vapp - 5kts, followed by an excessive thrust increase resulting in exceeding the target speed before finally stabilising at the correct speed. I’ve even had it a few times during the flare resulting in a loss of energy or excess energy. I’ve never seen this with CFM engines, or even older aircraft with IAE engines. Hence my preference for manual thrust in gusty conditions. Could slow A/THR response be the result of a software modification? It’s even noticeable when selecting open climb: after the engines have already spooled up, selecting a lower speed to increase the climb rate will initially result in a thrust reduction by the A/THR before increasing it back to CLB thrust. Again, I have never seen this on CFM engines.

Bus Driver Man

5th Sep 2020, 01:27

I am very wary of pilots who pull for speed or use manual thrust to override Airbus ground speed mini. (Not saying you do).
Completely agree. GS Mini is designed for a reason.
The only issue, and it’s quite rare, is that configuring might be difficult with a high target speed. It feels more comfortable to temporarily reduce the speed with a few knots before selecting the next flaps if the target speed was exactly VFE next.

Interesting to know is that the GS mini factor is different on other Airbus models compared to the A320CEO, eliminating a possible target speed close to VFE:Why is there a different ‘k’ factor for ground speed mini depending on the aircraft model?

The factor of 1 used on A320ceo aircraft could not be used for the other aircraft models due to differences of their deceleration capability. The A320ceo has a stronger deceleration capability when compared to A320neo, A330/A340 family aircraft, A350 and A380 aircraft.

In the case of a strong ground effect, a lower deceleration capability may lead to an excessive speed at flare. For example, a 20kt headwind at 200ft that reduces to 5kt on ground (corresponding to the 5kt tower headwind inserted in FMS PERF APPR page), a factor of 1 requires a deceleration of 15kt to reach VAPP. With a k value of 0.33, the aircraft only needs to decelerate by 5kt to compensate its lower deceleration capability. It reduces the risk of excessive speed at flare. The drawback is that there is a slight increase in thrust variations in gusty conditions, since the speed increment will not be sufficient to counteract the IAS increase due to a gust. The best overall compromise was demonstrated to be a 0.33 factor.

(Airbus Safety First July 2017)

TowerDog

5th Sep 2020, 02:00

I can see the 757 being a handful for an inexperienced pilot, but it is not a difficult plane to fly, or to land.
I needed an extra sector in the 757 as well, but we trained in the 767-200 and 767-300 every other sector, they each fly a bit different.
(probably had 35-40 hours total line training, the last flight from Boston a day or two before 9/11, same type and same airline that got hijacked and flew into the World Trade Center. :sad:)
Anybody needing a ridiculous amount of line training to land a 757 should find a different profession, it is not an SR-71 or some other exotic machine, lots or rudder and aileron/elevator control.

Uplinker

5th Sep 2020, 09:30

@Bus Driver Man

Depends what you mean by speed. The far superior Airbus groundspeed mini system will absolutely nail your groundspeed. And ground speed is of course what is important when landing, (as long as it keeps within sensible IAS limits, which it does).

As far as energy, well the ground speed mini system preserves energy, so even if the engines briefly reduce towards idle, the aircraft energy will be preserved, so no bad things should happen.

SOPs require the engines to be spooled up at 1000', and on gusty days with groundspeed mini there is a chance they might happen to be briefly at flight idle at this point. Personally, I am happy knowing the energy is preserved.

If the engines spool up massively just as you flare; they will be doing so to regain Vgs mini and preserve the energy, but if you think it is a problem you can just bring the thrust levers back out of the CLB detent early to limit this before pulling them all the way back to idle.

Your slowly reacting auto-thrust - don't know, but Airbus do consider the passenger comfort, so probably auto-thrust is programmed to be "gentle" while staying within flight limits. This might also be why some pilots think auto-thrust "overreacts", since on a gusty approach, it has to nail the groundspeed mini and cannot be gentle for that phase. So to those pilots, perhaps it suddenly seems a bit manic?

The older A330s I flew had 'lazy' auto-thrust in the lower levels, and I used phase advance (no longer approved) on a couple of occasions to keep the speed above Vapp-5

@Tower Dog. I agree. Years ago while still training, I once blagged a flight in a 757 FFS, having flown nothing larger or more complicated than a Seneca at that time. I was able to take off, fly a circuit and land, (fully manual everything), reasonably OK :ok:

vilas

5th Sep 2020, 11:40

@Bus Driver Man
Depends what you mean by speed. The far superior Airbus groundspeed mini system will absolutely nail your groundspeed. And ground speed is of course what is important when landing, (as long as it keeps within sensible IAS limits, which it does).
As far as energy, well the ground speed mini system preserves energy, so even if the engines briefly reduce towards idle, the aircraft energy will be preserved, so no bad things should happen.

SOPs require the engines to be spooled up at 1000', and on gusty days with groundspeed mini there is a chance they might happen to be briefly at flight idle at this point. Personally, I am happy knowing the energy is preserved.

If the engines spool up massively just as you flare; they will be doing so to regain Vgs mini and preserve the energy, but if you think it is a problem you can just bring the thrust levers back out of the CLB detent early to limit this before pulling them all the way back to idle.

Your slowly reacting auto-thrust - don't know, but Airbus do consider the passenger comfort, so probably auto-thrust is programmed to be "gentle" while staying within flight limits. This might also be why some pilots think auto-thrust "overreacts", since on a gusty approach, it has to nail the groundspeed mini and cannot be gentle for that phase. So to those pilots, perhaps it suddenly seems a bit manic?

The older A330s I flew had 'lazy' auto-thrust in the lower levels, and I used phase advance (no longer approved) on a couple of occasions to keep the speed above Vapp-5

@Tower Dog. I agree. Years ago while still training, I once blagged a flight in a 757 FFS, having flown nothing larger or more complicated than a Seneca at that time. I was able to take off, fly a circuit and land, (fully manual everything), reasonably OK :ok:
Chances of engines remaining spooled up are good in GSmini. Because its maintaining higher IAS in response to gust. Also the feature AB Approach ATHR is designed to be more responsive to speed variations below 3200ft. If very gusty conditions are expected it is better to add 5 to 15kts speed addition as permitted. I am a firm believer in taking manufacturer's opinion before trying something non standard. The are quick to respond.

FlightDetent

5th Sep 2020, 15:58

It’s even noticeable when selecting open climb: after the engines have already spooled up, selecting a lower speed to increase the climb rate will initially result in a thrust reduction by the A/THR before increasing it back to CLB thrust. Again, I have never seen this on CFM engines. It most certainly happens with old CFMs too.

Courtesy of fellow PPRuNers, you will find the technical explanation here if digging deep enough.

vilas

5th Sep 2020, 17:18

This is what I posted in 2019
The following information was released by Airbus in Sochi crash investigation:
The logic of integration of the autopilot/flight director (AP/FD) pitch control and the
autothrust control
¬If AP/FD pitch mode controls a vertical trajectory (e.g. V/S, ALT), then AT controls speed.
¬If AP/FD pitch mode controls a speed (e.g. OP CLB), then AT controls thrust.
¬If no AP/FD pitch mode is engaged, then АТ controls speed.
Logic sequence of the OPEN CLB mode
¬for level change more than 1200 ft:
¬at OPEN CLB mode engagement by the pilot, V/S control with V/S target = +8000 ft/min (40 m/s) is applied for AP/FD, and SPEED/MACH mode is engaged for AT
¬when engine N1 reaches 95% N1CLB mode, AP/FD switches to SPEED/MACH control law, whereas AT switches to the THRUST mode
¬Throughout this time the FMA displays THR CLB for AT and OP CLB for AP/FD
The given scheme of engagement for the OPEN CLB mode ensures the uniformity of the aircraft response in all configurations and within the whole range of the flight altitudes and speeds.
¬For level change less than 1200 ft:
¬at OPEN CLB mode engagement by the pilot, V/S control with V/S target = + 1000 ft/min (5 m/s) is applied for AP/FD, and SPEED/MACH mode is engaged for AT
¬ Throughout this time FMA displays THR CLB for AT and OP CLB for AP/FD
In this case the climb is in fact performed in the vertical speed control mode.
***
It should also be noted that if the OPEN CLB mode is engaged less than 30 seconds after the aircraft level off function is activated, the autopilot is authorized to use the vertical acceleration at the maximum value of 0.3g, whereas usually it is only 0.15g.