Uplinker

I fly Airbus A330. A lot of what the French captain apparently says is interesting and certainly food for thought - I don't see it as BS, perhaps someone could enlighten me - I don't think I could wade through all the AF447 threads again to pick out the facts from the nonsense.

Another interesting thing is that in all my recurrent LPC/OPC SIMs since AF447, I have not been presented with the situation that AF447 had. Yes, we have practised a bit of high level manual handling, and stall recovery, and unreliable airspeed, but I have not had everything thrown at me at once and at high altitude; Flying along at FL350 and without warning received unreliable airspeed, alternate law, A/P, A/THR and F/D, all dropping out, different FL presentation, a possibly confusing speed trend arrow, and several alarms going off all at the same time.

I think we should all be presented with this in our SIMs as an un-briefed surprise, and to enable us to possibly experience the confusion the AF447 crew had.

My trainers have so far not taken the opportunity to do this, which is odd.

PJ2

Uplinker;

So long as you know your memorized drills and the SOPs for running the ECAM and the paper checklists and set aside the initial surprise, you should be fine. Slow, deliberate actions, coordinated with the PM is all it takes - loss of airspeed indication is not an emergency at cruise altitudes, and the training for the drill provides (or should...it's an Airbus document), for the "flight not at risk" decision, (as opposed to just after takeoff or on approach).

Many here have expressed that they now pay much closer attention to both power and pitch attitudes during the flight and so are ready for "normal" should the airspeed indication be lost, while they get out the QRH for the precise numbers. That's just basic airmanship.

If you've done an unreliable airspeed event, you'll have seen what AF447 initially saw and experienced - you'll have lost the AP & AT with associated audible warnings and ECAM caution messages, (including lost ADRs), you will have dropped into Alternate Law and will have the greyed-out sections on the PFD where data has been lost, (no trend arrow). Not sure what else you wish to experience. But you could pull the sim up to 15deg and watch the THS, stall and watch the rate of descent. You can recover by holding the stick fully-forward until the FPV begins to come up from the bottom of the PFD. You'll feel when the wing begins flying again - takes about 45" and about 12,000ft, roughly, from FL380. Most level D sims will "simulate" the stall behaviour but it isn't based upon flight-test data as you've probably read numerous times.

As far as articles in magazines go, while they may hold interest for some, the best policy for those who fly these aircraft is to stick with just one book and know it thoroughly - the FCOM.

jcjeant

In an Airworthiness Directive (AD) effective January 14, 2013 (2012-24-08) on the B737, the FAA maintains that the loss of speed information is a risk "catastrophic" that could cause the aircraft go of the flight envelope "we Are Issuing this AD to prevent prevention ice from forming on air data system sensors and therefore loss of airspeed indication or misleading airspeed indicating indication on all systems, who could lead to loss of control of the airplane. "

It is interesting to read in this AD the FAA's response to Boeing that has the same arguments as EASA and Airbus, "if pilots follow the procedure it's going well": Boeing Stated That loss of, or erroneous, airspeed indications do not Necessarily lead to loss of control Because --other indications Can Be Safely used to fly the airplane. Boeing Noted That in multiple events-have service without loss of control Occurred When The flight crew procedures Followed That Mitigate the loss of air data.



FAA Response: whether or not a procedure does not change, the loss of speed information is a catastrophic risk. We disagree / ... / ALTHOUGH Some In-Service events might-have Occurred without loss of control, loss of, or misleading airspeed indication is all airspeed indicating indication systems can, in fact, lead to an unsafe conditions of loss of airplane control. FAA Advisory Circular (AC) 25-11A, dated June 21, 2007 Typically classified loss of all airspeed displays (Including the standby display) as a '' catastrophic 'failure condition.

EMIT

Unreliable airspeed events are a bit like phishing events for non-pilots:

If you receive an email requesting you to provide your bank account numbers and secret codes - nothing happens if you just do not reply, but all hell breaks loose (financially) if you are stupid enough to provide all the requested information.

With airspeeds indications going unreliable, nothing happens if you just keep the attitude and thrust as they were hours on end previously - however, if you react solely to the erroneous airspeed, all hell breaks loose, physically this time.

How do you distinguish between true and false? As a daily internet user, that should be as common as fish and chips in case of phishing attempts. As a pilot, same in case of unreliable airspeed.

EMIT

The questions about bank angle 67 degrees and g limit +2.5 appear to me to imply that people forget how airplanes are maneuvred.
Aircraft are maneuvred with LIFT, i.e. in the pitch direction.
If you want to turn, you roll to point the lift vector in the direction that you want to turn and then you pull to increase lift. If you dissect the lift vector you will find that in a horizontal turn, the vertical component of lift just counters the weight of the aircraft, and the horizontal component of the lift does the turning bit.
Now, if you are banked 67 degrees in your Airbus, or Boeing, which also has a g-limit of +2.5 and you want to climb, then the most efficient way is NOT to increase your pull on the stick, but to roll towards level, so that the lift will point more up.

Sometimes, you see referrals to high speed stalls - and then replies along the line of, well then just fly slower, that ends the "high speed stall" or an accelerated stall, which happens in a turn, etcetera.
Please note that stalling has to do with angle of attack (jeez, what an aggressive term by the way, couldn't we change that into a politically more palatable expression?). What is usually described on the forum here, as a stall, is the stall in level flight, at 1 g, which indeed will happen at the minimum speed, or stall speed. However, it is possible to increase angle of attack by just pulling back on the stick at any airspeed and in any attitude. Likewise, it is possible to be NOT STALLED at any airspeed, in any attitude by just unloading, pushing the stick untill you are weightless in your seat - the airplane then also needs no lift.
This latest sentence may attract engineering wonders that will figure out super efficient flight, no lift needed, so less engine thrust needed, etcetera, but of course, no lift means that gravity will succeed in pulling the aircraft closer towards earth, so it can only be used temporarily, e.g. to get out of a stalled situation - regaining level flight is than an item lower on the priority list.

Questions about getting the Airbus into Direct Law by pilot action - if needed, push 2 buttons. There are 3 air data computers (ADR, air data reference unit) - switch OFF 2 of them and the system will fall back to direct law. If attention was payed during type qualification, procedure should sound familiar.
Concerns about upsets - when outside normal pitch and roll limits, then system reverts to abnormal attitude law - in that law, the flight controls will act "like in a normal aircraft again", no "interference by unwilling computers anymore".

Derfred

If Airbus pilots are not trained to regard the aircraft's attitude indicator as their primary instrument, then we have a problem.

I don't care about laws, sticks, bells, alarms, ecams, modes or ergonomics.

If Airbus pilots are not trained to regard the aircraft's attitude indicator as their primary instrument, then we have a problem.

vilas

EMIT
"Questions about getting the Airbus into Direct Law by pilot action - if needed, push 2 buttons. There are 3 air data computers (ADR, air data reference unit) - switch OFF 2 of them and the system will fall back to direct law."
No it doesn't. It will change to alternate law and not direct law. Even all three ADR fail you go to alternate law but without protections and 67 degrees bank and 2.5 G is well beyond the demands of commercial flying. It is just theoretical discussion. If Airbus pilots were not trained to regard attitude indicator then they would not have installed it. Pilots are trained to monitor speed and glideslope and again and again we find they don't. SFO B777 last year and Bangalore in 1990 on Airbus are mirror reflections.

EMIT

You are correct Vilas, switching OFF 2 ADR's indeed puts system in ALT law, not yet DIRECT. However, with the protections gone, it is still enough to get out of a hypothetical overspeed pull up such as being advertised on the Air Asia thread. Have been too long away from the bus now to get it right the first time.
Agree fully with your remark with regards to basic flying.

karnc

Flying Airbus is not like flying conv. Airplane. It's not that simple and easy to fly when in atn law and so many warning plus some protection the computer is confusing about.

When the Bus is messed up, your conventional pilot skill can't help much because when you pull the stick, the plane may not respond by raising up the pitch.

Pilots with thousands of bus hours still have difficulty pulling a level 45 bank in altn or direct law. I am a sim instructor and believe me, i see this all the time.

FBW from boeing and airbus are so different. With airbus, you don't feel anything. It s very easy to fly when there is nothing wrong, much less workload than boeing. But when things get fk up, airbus can confuse the pilot even he has ten thousand hours.

Uplinker

Yes quite, but my point was I have not done all the above simultaneously at high altitude. Nor have I been shown a deep stall and its recovery.

In fact my response to an unreliable speed event in the SIM (at about FL150), when it was obvious that only my speed tape and trend arrow were going crazy while the PNF's and the STBY were rock solid, was that I did nothing except keep attitude and power. But I got marked down for that because the TRE wanted to see me do the unreliable speed drill !

When does this happen? You should be able to stabilise an Airbus just as you can a Boeing, as long as you look at your instruments and fly Pitch + Power = Performance.

Even if you have lost all your ELACs and SECs or PRIMs and SECs, you can still maintain the approximate flight path with the THS and rudder - both under direct pilot control - while PNF starts resetting the computers.

vilas

karnc
I am really aghast at your statements. Alternate law is no different than normal law except the protection part then why would Airbus not pitch up when you pull the stick? If that were to happen the aircraft wouldn't be allowed to fly.
Pilots with thousands of bus hours still have difficulty pulling a level 45 bank in altn or direct law. I am a sim instructor and believe me, i see this all the time.
Any body who wants to do 45 degrees turn in alternate law/direct law surely has to be out of his mind. You are not training A320 aerobatic team are you? You are wasting their precious SIM time. About piloting skills first you have to have them and they will stand by you the accidents we are discussing the pilots have shown alarming lack of it.

PJ2

vilas;
Sorry, I'm confused by your post because there is a disconnect in your statements above.

How can practising basic piloting skills be a waste of sim time? Isn't this one of the aspects of these accidents being discussed...that pilots are losing their basic handling skills?

Fourty-five degree bank turns to the left and right are standard simulator exercises. That they are done in alternate and direct law for the A320 is even better because in Direct Law, the pilot has to trim manually.

The exercise is a quick way of determining a pilot's flying skills, and then on with the rest of the sim. If problems show up here, that is the place to stop for a moment and instruct/practise.

In fact, there is a discussion about such handling exercises back a few pages in the thread, beginning at: http://www.pprune.org/tech-log/53975...ml#post8823573, regarding "S-turn" exercises, which are a bit more difficult and are certainly worth the time in the sim.

Regarding your statement, "About piloting skills first you have to have them", of course, and the way to get them is to practise, practise, practise. All pilots should be able to do these exercises with a high level of accuracy and finesse. If they can't, then they need the sim practise to raise the level of skill so that they have them.

Once they can do the 45deg bank turns and the normally-banked S-turns with changes of altitude and speed, (in Alternate or Direct Law, with manual thrust) they could be considered to have a high degree of manual handling skills.

Such an accomplishment and level of skill is a great builder of confidence in oneself and the airplane. These are building blocks, upon which an understanding of the Airbus systems and procedures can then be built. This works even if one has been flying the Airbus for years.

karnc;
I agree with you; in fact knowing that the Airbus is different is necessary before one can begin learning about the Airbus when transitioning from a Boeing or other type.

To emphasize, there are differences between the Boeing and Airbus and those differences need to be understood by the instructor and taught to the students. The number of hours a pilot has may not help if the pilot hasn't been taught how to fly the Airbus or doesn't understand the fly-by-wire system, (known as C* or C-star laws).

Fly-by-wire is something like CWS, (Control Wheel Steering) in a Boeing, (but for very different reasons!).

While the airplane is different to fly, it is also simple to fly but one must first understand the fly-by-wire system, (which is completely different than "the protections" which can be learnt later).

Forgive me if you know fly-by-wire systems; - the following may help others.

When one pitches up/down or banks a conventional aircraft, after doing so one neutralizes the controls of course but a conventional aircraft will wander a bit in pitch or bank so one continuously, subconsciously makes tiny corrections to keep the airplane where one wants.

With Airbus FBW, when one pitches or rolls using the sidestick, one is asking for an amount of 'g' in pitch, and a roll-rate in bank.

When there is no further "request" for more/less 'g' or roll-rate from the stick, the flight control system actively maintains the last pitch attitude and/or bank angle.

Put another way, the autoflight system (not the autopilot but the FBW system), will act to maintain the last pitch and bank angle "selected" by the stick. So long as the stick is neutral, no further "orders" are being sent to the ELACs/SECs and the pitch & roll attitudes will remain until changed by the pilot.

When pitch increases, with the autothrust engaged the engines will increase power just as we would in a conventional aircraft. If one is in manual thrust, one adds power as in a conventional aircraft.

Also, the autoflight system will trim the aircraft if such is required. Similarly, with bank angles up to 33 degrees, the flight control system will work to maintain the last-ordered bank-angle, increasing thrust and trimming as required. Beyond 33 degrees the THS will not trim and the pilot must pull on the stick to maintain altitude say, in 45-deg bank turns. If the autothrust is engaged, it will add thrust to maintain speed.

You can hopefully now see why this is similar to the Boeing CWS but is actually, fundamentally quite different than CWS.

If your pilots are having difficulty with 45-deg bank turns that is just a sign that their basic handling skills require gentle verbal correcting and then practise, with encouragement and feedback from the instructor.

Flying a 45-deg bank turn in any transport aircraft is a challenging exercise precisely because we don't do it often and need the practise.

Flying 45-deg bank turns in Alternate and Direct Laws is the same as doing the exercise in a conventional aircraft.

The stick is smaller than a standard control column so you have to make gentler and smaller adjustments otherwise the airplane will feel quite sensitive to control inputs - other than that, it just requires practise.

The added benefit in doing steep turns in Direct Law is that one must trim just as in a conventional aircraft, by rolling the trim wheel back.

Doing it with manual thrust is even better as the coordination required is significant, and is the measure of the level of handling skills every pilot should have.

Such exercises should never be a "test" - they should just be done in the sim until each pilot is proficient at the exercise. It takes about 20 minutes of sim time unless some instructing and practise is needed.

If the exercise does turn out to be a bit of a mess, help by gently correct the pilot and try again. A high number of flight hours does not guarantee skill or understanding, nor does a low number of hours prevent skill or understanding.

With practise pilots should be able to do it, maintaining both speed (+/-10kts) and altitude (+/- 100ft), rolling out on specific headings. Again, those limits aren't a "test", they're a goal, and when achieved they show that the pilot has the necessary manual handling skills for his or her aircraft. As John T. says in the previous discussion, gentle encouragement and suggestions produces very good results and confidence.

The climbing and descending S-turns described at the above link would be the next step in the practise and exercising of handling skills

Once one knows these differences and understands them, the Airbus is a delight to fly - as easy as the Boeings, in climb, cruise and descent. I've flown Douglas, Boeing, Lockheed and Airbus types in all regimes and they do not present a problem hand-flying them.

In my opinion, anyone claiming that the Airbus is "difficult to fly at cruise, like balancing a ruler on the tip of one's finger", doesn't fly transport aircraft let alone the Airbus, doesn't know the Airbus and shouldn't be saying such things to others who read their stuff when they don't know such things, no matter how many letters are in front of or after one's name...

Uplinker;

In 2006, Airbus issued guidance on how the UAS drill & checklist should be handled. The Airbus document may be found at http://home.base.be/fabrot31/airbusunreliablespeeds.pdf. The guidance is also in all FCTMs that I've examined, all of which were in the Manual prior to June, 2009.

Along with the standard sim exercises, your employer should be teaching the UAS drill because it is a known issue. The reason why accident reports should be required reading for air carrier managements is to understand why certain training priorities and regimes should be planned and appropriately resourced. If the requirements of the requlator are such that sim time is already at a premium and there is no time for the basics then that needs addressing first within the individual carrier, (why is there no spare time?) and then in proper venues in communications with the regulator...much slower, less effective I know but speaking up is the only way things change.

BTW, "deep stall" only refers to T-tail aircraft in which the horizontal stabilizer & elevator system is blanked by the low-energy airstream from the stalled wings. AF447 was not a deep stall, and in fact the tail was never stalled, (and the airplane could have been recovered using elevator alone if the stick had been held fully-forward long enough...they just stopped too soon because they didn't comprehend their situation and the re-occurence of the stall warning confused them. The indications of a full stall were however, present - an inability to arrest a high rate of descent when the nose is pitch up, etc., etc.).

I would like to add a link to a BBC Radio 4 discussion on cognitive science that may be found in the Air Asia thread on R&N because I think it is worth listening to. The broadcast is at: http://www.bbc.co.uk/programmes/b0505zw1

CONF iture

That would be an excellent practice to be repeated every 6 months, but the reality is very different as every sim session is already largely overloaded to try to fit the program as specified by the local Transport Ministry.
Another positive development would be to allow each pilot a 20 min period to practice whatever he likes ...

Not too sure about that ... had always the feeling to have to wait for the trim to do what I would have done before ... 757 was a delight.

This was an incomplete document especially following the multiplication of UAS In cruise phase. A simple procedure should have been published to specify what a crew has to concentrate on :

• Pitch 2.5 deg
• ENG N1 80%
• And wait ...

alf5071h

Many posts in this thread and elsewhere infer that crews’ lack flying skills, yet none of the accident reports substantiate this. Even the researches have mixed results when looking at skill degradation with autopilot use.

There is no indication from everyday flights that handling skills for normal operations are less than required; however non-normal indicators suggest otherwise. Thus the safety focus should be on how non-normal situations are encountered, - handling skill or awareness. Many LoC accidents were self-inflicted, the unsafe flight condition was created by the crew – they stalled the aircraft, and having done so by ‘conscious’ action might be less amiable to reconsider the situation and changing the course of action. These are mental skills not manual skills.
Thus the need is to improve appropriate awareness in these unusual and rare situations, the skills of assessment, and reconsidering and changing actions.

More manual flying in benign conditions is unlikely to improve skills for LoC recovery. Some manual flight might improve skills of awareness, but not necessarily be effective in self-created surprising conditions.

There is no easy solution; greater background experience and skills in non-normal situations could help, but never guarantee that every situation will be covered nor that the crew will call upon the skills.
Protecting crews from these situations in general has been successful, except of course when the protections are degraded, yet again not every situation can be foreseen.
Instead of chasing the negative aspects of this accident, seek to understand how those crews who avoided or recovered from the same situations; then do more of what they did.

AF447, the protections degraded; improve the protections ... action in hand.

vilas

PJ2
In a 45 degrees turn you need to monitor bank, pitch, VS and speed so it is a good exercise in commercial jet to develop a efficient scan and not because you will be required to do it. As an airbus pilot you will understand you only get direct law with gear down and you don't do steep turns with gear down. Direct law is a short term state given to you as a flare mode of alternate law to help you keep a steady pull on the stick during flare and landing. That is why it transitions to that only with gear down when you don't even bank 10 degrees. I have five type ratings(including one in the US and one in France) and nobody ever asked me to do steep turns with gear down notwithstanding the FBW. As far as alternate law is concerned it is same as normal law except the protection part so any one who cannot do a steep turn in alternate law won't be able to do in normal law either. You need to inculcate respect for Alternate law by emphasizing careful handling within the envelope and not ask them to do steep turns. The S turns (climbing level then descending) you are talking about are the first thing that are taught to non jet pilots in flight and navigation procedure training(FNPT). The type rating begins with this and raw data flying FDs, bird and ATHR off departures arrivals and approaches in fix base SIM. However many airlines have their own syllabus called MCC which is a bad short cut in which they perform only one or two sessions in FTD and the rest in MFTD or APT as it is called now. These trainees struggle in the sim. Ultimately it is a business as any other and financial pressures make a mockery of professional requirements of cockpit crews.

PJ2

CONF iture, thanks. Yes, have done such compressed sessions and one never feels as though one accomplished anything, but ticked the boxes. Retirement certainly has its pleasures...

Re,

• Pitch 2.5 deg
• ENG N1 80%
• And wait ...

Agree with you, - as I stated in July of 2009 and hence, essentially "do nothing", http://www.pprune.org/tech-log/37643...ml#post5058695 ... ;-)


alf5071h, as always, a pleasure to read your thoughtful posts - no big disagreement with your thinking here, but still a question mark perhaps, beside the manual-handling-skills item in the list. Thanks for adding to the dialogue.

vilas, thanks for the reminder on Direct Law & the gear. Seven years away has its downside...

vilas

CONF iture
... had always the feeling to have to wait for the trim to do what I would have done before ... 757 was a delight.
Can you explain a little what exactly you mean by that.

RetiredF4

I have no intent to argue with your POV, but to clarify things up I have one question:

Are you saying, that direct law will not happen due to system degradation or any other FBW malfunction except with gear down and therefore flying in direct law with gear up has not to be trained, or is direct law in the sim only achievable by putting the gear down?

I think the point of the mentioned exercises by PJ2 is, that if you can do a 45° bank coordinated turn without crashing you can do turns with less bank as well and the execution uses less brain cells when trained to the extreme than when untrained and unexpected events arrise. And doing them in normal law with all gadgets working seems a bit easy in the bus regardless of bank angle.
Concerning alternate law being like normal law without orotections I like to remind that it comes with two different sublaws, one of them Alt2B with roll direct like in AF447, where Bonin had a hard time to cope with roll from the beginning.
"Lazy eights" like we military pilots had to practice would be a good exercise to expierience the different roll characteristics in Alt2b under a variety of speeds which come with the maneuver.

@alf507h
Theoretical knowledge is essential for handling skills, but never can replace actual handling. When germany was in the middle of the "Starfighter crisis", the MOD Steinhoff ordered more flying practice to increase the flying skills of the pilots, and while the flying hours went up the losses went down. It is not either improvement of theoretical knowledge or increase of manual flying skills, it is both.

vilas

RetiredF4
There are only two listed failure which put the aircraft in direct law. One is transitory and pilot recovers to alternate law. The other is permanent when you loose both the ADIs and have to fly by the standby system so no help. You don't need steep turns in direct law. PJ2 understood what I am saying. Alt1 or Alt2 there is nothing to practice except fly it properly within the envelope. Please leave AF447 out as it is a long list of what not to do and what he didn't know how to do. Even normal law protections are not meant to be evoked through sloppy flying. There are hundreds of airbus pilot retiring every year without actual experience of any protections. Problem is pilots are becoming complacent with automation and loosing their scan and not monitoring speed or attitude or bank. They need basic raw data practice nothing to do with any law. Unlike military there is a commercial pressure on training. Airlines would rather save money on training for something that is not likely to happen or just do it to tick the boxes.

Microburst2002

Negative!

DIRECT LAW handling characteristics are NOT like a conventional airplane's, no matter what Airbus claims.

Sidesticks give no clue of airspeed, like conventional airplane yokes do. Specially in steep turns, g force feeling is a cue that will tell you when to ease the bank, get back to altitude and roll to 45º again. Sidesticks give no clue of anything.

btw, I think steep turn training is a waste of sim time.