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AF 447 Thread No. 12

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AF 447 Thread No. 12

Old 30th Nov 2014, 06:04
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No it wasn't -
yes it was - 1980s?

As for the rest of your post. Maybe you should re-read mine?
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Old 30th Nov 2014, 20:16
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I feel that Doze does not get my point. But in his defense....

- automated flight path systems were there when I first flew an interceptor in 1966. We had "coupled" approaches, climb gradient, course, even attack steering, et al. The F-106 was even more integrated than my VooDoo. Using datalink from the ground, the sucker would fly the jet to a bandit location so the pilot could lock on and shoot.

- the VooDoo had AoA and gee limiters just like I saw 13 years later. Also had a pneumatic bellows doofer that kept us from pulling too hard on the stick according to dynamic pressure ( basically CAS).

- VooDoo had a pusher that activated according to both pitch rate and AoA.

OTOH:

- The problem with the engineers designing and implementing FBW was trying too hard to "protect" the pilots.

- You really have to look at the FBW implementation and then fly a plane using it to completely understand some of my views.

The so-called "direct law" would not be easy to fly, and not hard at all for a really good pilot. After all, we have not had a lotta cables, pulleys, pushrods and such connecting the yoke or stick to the control surfaces since the late 50's. Springs and maybe active feedback stuff for the stick/yoke would help a lot, and they are available now! Some online flight sims even have force feedback sticks to represent WW2 aircraft forces.

- the Viper had many "protections", but many were intended to represent what all the pilots were used to in terms of rates and gee/stick force and so forth. So our pitch and roll rates were "limited" ( most here know I detest the term "protections"). Our gee and AoA were also limited according to a basic function that allowed 9 gees until 15 degrees AoA, then decreasing to 1 gee at 27 degrees AoA. We had no absolute pitch or roll limits such as the 'bus. Was the nature of our mission, duhhhh.

What got our attention after a few crashes was an idea from the engineers to use our system to pull up according to HAL's idea of imminent ground impact. NO WAY!! The consensus amongst us was to allow us to die if we screwed up!!! Put up the big, flashing "X" in the HUD and have bitching Betty yell at us, but that's all. Same as that Russian jet in Malaysia or Indonesia, when the pilot turned off the ground clearance alert system, but sadly took a lotta SLF with him into the cliff. Don't like being brutal, but that comes from my decades flying a different mission than the commercial folks.


My bottom line goes with PJ's. Fly the jet as much as company policy allows you without getting fired. The "engage otto at 300 feet and disengage for last two miles on final" attitude or procedure deeply disturbs me.
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Old 30th Nov 2014, 22:41
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Dozy,
the cost savings in pilot training that Airbus touted with the introduction of their FBW types had absolutely nothing to do with increased use of automation, and everything to do with the unprecedented level of commonality in flight deck layout and "feel" between their narrowbody and widebody fleet.
I don't think you interpreted Cool Guys comment correctly:
They probably never dreamed that airline cost saving measures would actually ban pilots from manual flying.
In fact, sadly, airlines have banned manual flying unless some extreme reason calls for it, the gospel according to airline bean counters. Then the airline lawyers chime in with the possibility/probability of tort action resulting in manual flying should something go wrong, not being in auto-flight.

IMHO, what wasn't recognized in the '80s was where the source of pilots was going to come from in the later decades. While Gordon, Bernard and others of the '80s came out of the military experiences of flight training, discipline and introduction to aircraft testing, far more pilots today emerge from commercial, for profit, flight schools and proceed into commercial airlines starting on the commuter level at poverty level pay, without their military experiences. Did Gordon and Bernard take this into account when developing the Airbus FBW systems and sub-systems, or was it based on their personal experiences? What kind of personalities did they have in their leadership roles at Airbus? Was Gordon and Bernard really open to changes/criticisms to the FBW systems they promoted, or were they overbearing/dismissive to subordinates with their supposed greater knowledge and experiences?

Airbus Industries indeed pushed the reduction of training costs to airlines, even beyond that of what was happening with two seat cockpits, i.e., elimination of the flight engineer.

You have an opinion, but you are not the final word in this discussion.
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Old 30th Nov 2014, 23:59
  #804 (permalink)  
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gums,

Two thoughts, re "Fly the jet as much as company policy allows you without getting fired. The "engage otto at 300 feet and disengage for last two miles on final" attitude or procedure deeply disturbs me. "...

1) In my experience, which I suspect is not unusual, it is rare not to engage the autopilot right after takeoff, and leave it engaged until about 400' on the approach.

2) Every company flying heavily-automated equipment these days must have an automation policy which clearly states appropriate levels of automation so the carrier's crews know when they can legitimately disconnect and hand-fly.

If an airline is prohibiting or limiting its crews from hand-flying either by direct policy or through inappropriate limitations on hand-flying or is entirely without an "Appropriate Level of Automation Policy", then it is only a matter of time before they will find themselves dealing with an incident in which reduced hand-flying thinking-capability and hand-flying-skills will have played a part. Like not doing flight data analysis, these days that puts an air carrier at risk of liability if anything happens.

We are a very, very long way from absenting such skills in our transports.

Turbine D

Re, "What kind of personalities did they have in their leadership roles at Airbus? Was Gordon and Bernard really open to changes/criticisms to the FBW systems they promoted, or were they overbearing/dismissive to subordinates with their supposed greater knowledge and experiences?

Airbus Industries indeed pushed the reduction of training costs to airlines, even beyond that of what was happening with two seat cockpits, i.e., elimination of the flight engineer.
"

I transitioned to the A320 left seat from the B767 right seat in 1992 - the Airbus had been in service for approximately six years by that time.

While I found the airplane "natural" to fly, (including just pulling the thrust levers out of the CLB detent and using them as one would any other transport), I found the course over-emphasized automation and I found when we met with Airbus personnel who came over by invitation to engage those transitioning to the airplane they were dismissive of our thoughts on aspects of the design and of some of our questions, (no one had ever flown FBW; also, we initially flew the A320 without full VNAV, so used traditional methods for descent). Our instructors were capable but just ahead of the class, but that part was okay because the airplane flew just like an airplane so most were comfortable. The hardest part of the transition was actually going from the right to the left seat as there were commander's duties to ensure as well as getting the airplane under one's belt.

It was the first time in my career that I had done my entire transition to a brand new type entirely on the autopilot - hand-flying was discouraged because they wanted a quick understanding of the automated flight features (that they had paid for, in my view). I thought the airplane was exceptional then and now, but the automation was subtely viewed, in my opinion, as "the third pilot", even as that may not have been the intention they were trying to convey.

It was a long time before Airbus actually began to engage "ordinary line pilots", the airline and their collective comments; - after a few incidents and accidents they began to listen, is how I recall it. Once they understood that the end-users had valuable things to add to their own understanding of their aircraft and its substantially-different (but in my view highly-successful) design, it became a good conversation although in my view very late in the game.

As a result, (and you are correct, in my view), airlines indeed accepted the Airbus "push" regarding reduced training costs and the benefits of automation. Having hand-flown everything I ever trained on, I hand-flew the Airbus too, during line-indoc and every chance I got, while our representatives fought to include in the FCOM a paragraph in the SOPs permitting hand-flying; (the only statement governing this in the FCOM was essentially, "the autopilot and autothrust will be engaged shortly after takeoff and disengaged during the landing roll-out".) So if one had an incident while hand-flying, one was in trouble...It was many years and after a number of incidents and accidents in the industry, before a proper automation policy was created and adopted. I have materials going back to 1990 (from AW&ST) discussing this problem which was raised by flight crews at the time. I am still astonished that it took twenty years to comprehend the combined problems of automation dependency and a new generation of pilots raised on computers with little real (vice virtual/cadet) experience.

Last edited by PJ2; 1st Dec 2014 at 17:57. Reason: Add response for Turbine D
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Old 3rd Dec 2014, 14:33
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Few points to address, so here goes:

@gums - I think what might be worth bearing in mind is that your Viper was intended to be flown by fast jet pilots, and as such they would routinely be trained in the limits of the aircraft when making extreme manoeuvres. That kind of EFCS exists because the aircraft itself is inherently unstable (in order to maximise manoeuvrability) - a completely different set of requirements from those which would be needed in an airliner.

As such, protection features such as those in the FBW Airbuses and Boeings would be inappropriate in the Viper, because Viper pilots would be expecting to fly the thing at or near the limits on a fairly regular basis - which is absolutely not the case in the airliner use case. What may be "trying too hard" in the Viper may be just about right in an airliner.

Again, this is something I've brought up before, but the Airbus (and later Boeing) FBW "hard" protections are not just about sparing the blushes of the flight crew, and while this aspect was emphasised to the general public (who in 1985 had seen one of the worst years for airline safety on record), the other equally important aspect was that the hard protections allowed the crew to deliberately use full control deflections in an emergency scenario without worrying about stalling/spiralling the aircraft or overstressing the airframe. This is important because - unlike your Viper crews - airline crews would not be regularly expecting to take the airframe to its limits and would therefore not train or practice the need to manually hold the aircraft within those limits.

@Turbine D:
IMHO, what wasn't recognized in the '80s was where the source of pilots was going to come from in the later decades. While Gordon, Bernard and others of the '80s came out of the military experiences of flight training...
To be fair, I think it's worth noting that the situation in Europe regarding airline hiring was somewhat different to what it was in the USA if we're talking about the period between the start of the '60s and the mid-'80s. I recommend Blind Pew's book for a fascinating insight into BEA's cadet programme in the '60s, for example. I think in general, you tended to get fewer ex-military folks crossing over to the airlines on this side of the pond.

That's a bit of a tangent though - the whole point of the Airbus FBW/EFCS development was to be able to encode the experience that Gordon and the other test pilots had gained when testing the airframe into the computers, so that pilots of any ability would be able to draw on that experience transparently. As such, one could almost say that they were absolutely preparing to deal with a wide range of piloting abilities from
the very beginning.

Did Gordon and Bernard take this into account when developing the Airbus FBW systems and sub-systems, or was it based on their personal experiences?
See above. I should also take this opportunity to point out that BZ would have only been involved in the specification of the systems at a fairly high level - it would have been GC and his team who did the actual test cycles and feedback sessions. From what I've been told, it would be inaccurate to speak of the two men in the same breath/sentence in that regard. BZ was senior VP of engineering (and as such largely a ceremonial figurehead), whereas GC was a lead test/engineering pilot in the programme.

What kind of personalities did they have in their leadership roles at Airbus? ... open to changes/criticisms to the FBW systems they promoted, or were they overbearing/dismissive to subordinates with their supposed greater knowledge and experiences?
I can't speak for BZ - though, as I said above, he wasn't really involved in the day-to-day testing/feedback/redesign/tweaking cycle that GC's team were. As far as the A320 project goes, BZ would have been on the flight deck for "marquee" flights (e.g. first prototype flights), particularly where the press were involved - but he would not have been involved in the regular testing and development schedules. GC was the lead engineering pilot and would have been in charge of the "real" work.

I've been fortunate enough to correspond/speak with a couple of people who knew GC - and both of them said that the way he came across was as personable, knowledgeable, meticulous, methodical and inclined to listen and mediate within discussions as BZ could come across somewhat brash. This is one of the reasons why GC had the role he did. I should also point out that GC was involved in the Concorde "minimanche" experiments (where what became the Airbus sidestick design was first developed and tested), whereas BZ was not.

Something which folks may find interesting is that the groups who are most vocal in criticising Airbus like to bring up BZ's character, chequered history, brashness and his foot-in-mouth tendencies at the drop of a hat - but in my experience barely acknowledge GC at all, either in terms of his character or his greater technical contributions to the project. My personal belief regarding this is that to do so would tend to rather undermine their position and argument.

I've repeatedly put forward the viewpoint that had GC lived longer, the festering distrust in some piloting circles towards Airbus would never have taken hold - and I think the manner of his passing speaks volumes about his character. After the A320 testing project concluded, he transferred to the position of deputy flight safety director. In that position he did not necessarily have to personally visit accident sites, but clearly felt compelled to do so. Sadly this led to his death from altitude sickness when personally overseeing Airbus's safety team on a crash site in the Himalayas.

even beyond that of what was happening with two seat cockpits, i.e., elimination of the flight engineer.
Two-seat flight decks had been the norm in Western narrowbodies/short-haul types since the mid-60s (e.g. BAC 1-11, DC-9, Jurassic 737). The A300 may have been the first two-seat widebody (and indeed the first long-range twinjet), but Airbus were only following an already existing trend - the B767 was also a two-seater twin, flying for eight years before the A320 went into service.

@PJ2 - As usual, a very cogent post, though I have to wonder:
It was the first time in my career that I had done my entire transition to a brand new type entirely on the autopilot
I suspect you'd have faced the same situation had you been doing a type conversion to, for example, the B757 (which had an FMS/autoflight setup practically identical to the A320). On balance, everything I've read indicates that a move to increased use of automation was industry-wide and related to the period of time rather than the type.

I'm just "thinking out loud" here, but I wonder if the emphasis on training the automation in the early days of the A320 may have had something to do with the fact that most of the short-haul crews undergoing conversion training at that time would have been used to aircraft two generations older (e.g. Caravelle, BAC1-11, DC-9), and as such, the change in automation technology might have been considered the biggest change to overcome, and prioritised accordingly?

It was a long time before Airbus actually began to engage "ordinary line pilots", the airline and their collective comments;
May I ask how long, in your experience? Again, based on what I've read I agree absolutely that Airbus did seem to drag their heels in that regard - but at the same time I wonder if other builders were much different back then. There have been several examples I can think of where manufacturers were reluctant to respond to queries/criticism (e.g. Bryce McCormick to Douglas regarding possible total hydraulic loss on the DC-10 and Boeing's efforts to suggest B737 rudder PCU problems were in fact handling mistakes by the crew).
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Old 3rd Dec 2014, 16:22
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Again, this is something I've brought up before, but the Airbus (and later Boeing) FBW "hard" protections are not just about sparing the blushes of the flight crew, and while this aspect was emphasised to the general public (who in 1985 had seen one of the worst years for airline safety on record), the other equally important aspect was that the hard protections allowed the crew to deliberately use full control deflections in an emergency scenario without worrying about stalling/spiralling the aircraft or overstressing the airframe.
It was and still is a clever move to sell the flight envelope protections only as a device to protect the aircraft from the pilot inputs and to allow them to use maximum control imputs without thinking too much about stalling or overstressing the airframe. Those envelope protections are a necessary gadget to prevent the FCS in a flightpath stable setup from exiting the flightenvelope with no corrective intervention by autothrottle, autopilot or human pilot. It is probably a philosophical point which need was first, to implement a system which sets limits to the FCS and regains the necessary positive static stability at the edge of the flight envelope or to implement the system to aid in piloting the airframe at the borders of the flight envelope. Both purposes are served well. But without those protections the flightpath stable C* design would hardly have been certified by the authorities.
But I agree, the official version sells better.
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Old 3rd Dec 2014, 19:58
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AF447 : Commentaires - Page 30

Item 2 of the BEA:
- Inappropriate actions on orders destabilizing the trajectory;
Certainly, if the shares were appropriate there would have been no accident.
Regarding the first few seconds, extracted from forensic report:
The pilot responds to the alarm ... ... his first actions are consistent with the pursuit of mastery of the path by controlling jerk reaction based on the information available ...
This is consistent with the indication of the tendency bar flight director whose order is guiding nose ...
It is said at the beginning, so good ... then it goes bad ... Why?
Well, because ... see the list of the post before and its consequences on the steering screens:

Enough is enough.
Noting two points:
• the difficulty of driving a hybrid law, little change in the pitch axis but almost doubled rates on the roll axis that mobilized too pilot resources which could not cope with everything else, including consequences of the reactivation of the FD, the Flight Director.
• To underestimate the difficulty of the action suddenly doubled roll rate, experts have reconstructed the drivers as follows:
- 5 sessions of simultors some dedicated solely to the acquisition of control in Alternate 2B, without any failures elsewhere.
- Day demonstration flight in good weather, with no parasite fault, no uncontrolled descent commissioning, no setting unexpected turn, no ECAM messages and alarms of various failures, and especially no effect surprise.
Knowing what was going to happen, the pilot obviously moved with his shy moderation Sidestick to conclude:
"Compared to conventional aircraft, the pilot of the aircraft alternate 2 law, at high altitude, is very easy."
In these circumstances, I want to believe ...
To overwhelm the pilots could not do better than this travesty of flight "demonstration" ...
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Old 3rd Dec 2014, 21:58
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Dozy;

My experience is one of thousands as are my impressions of the process and the airplane.

I remember the move to 2-pilot wide-body aircraft - our B767's had a third seat but by the time I trained on the airplane everything was up front. I loved the FMC technology...we were experimenting with early versions on our B727s. I trained on every transport we had except the B747 and no course was focussed so strongly on the automation as the A320 one was. There was perhaps an approach or two on raw data/no FDs and a few with all ELACs/SECs gone, (differential thrust & trim used to land the airplane, er, simulator) but aside from that, the entire simulator course was on the autopilot and I did the licensing ride and the command ride entirely on the autopilot. I know very well that others would have been different.

Regarding other manufacturers, it wasn't so much the visits but the diffidence with which our entreaties were handled, at least in 1992. It changed massively after 1999 or so, and so did their publications which I think are among the best in the transport world in terms of sharing information, flight safety and support for users. In fairness I have to acknowledge that the floor tours I've had of the Boeing plant at Everett were second to none in terms of openess from the senior pilots taking us around, (just as the first three B787s were rolling off the assembly line, bound for ANA).

It's tremendously complex and I respect others' views that inevitably will be different than mine regarding this whole introduction to automation - which, I have said, I love and used on all types with great enthusiasm as I did the control column or sidestick and non-moving thrust levers!...one can't really categorize it so much as recall impressions and experiences. It's like trying to perceive the British Museum in the dark using only a small flashlight as one's guide!
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Old 4th Dec 2014, 19:25
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Viper versus 'bus protections

I do not like correcting Doze or others, but have to clear up the comparison with the 'bus "protections" and the Viper "limits".

Make no mistake, the intent and implementation of the AoA and gee and pitch rate and roll rate limiters on the F-16 were exactly what we have been talking about. Duhhh? Gums! What do you mean? ( now that PJ has opened up, I feel I owe all the same courtesy)

I was one of the biggest advocates of a mechanism to override the F-16 limiters. Problem was I didn't understand FBW system implementation or design. This is back in 1974.

I flew the VooDoo 1966 - 1967, and it had an AoA and gee limiter in some modes. It also had a "pusher" for excessive pitch rates as well as pulling thru the mechanical limit for AoA. So I was there with some of the "interference" with we cosmic pilots that could do anything, fly anything , heh heh. Nevertheless, the sucker had an electro-mechanical analog system for flight envelope protection and an actual flight path autopilot ( called it the coupler). I even used the coupler to launch a Genie rocket at a drone because it was better able than me to steer and avoid the dreaded "pitch up" ( had a poor set up, and was sorried about pulling too hard). I also used it every now and then for a coupled ILS approach, but we didn't have autothrottle, so we pilots still had a few duties ( think Asiana airspeed monitor duties).

The Viper limiters were exactly what we are talking about with the extreme envelope 'bus "protections". They are there to keep Joe Baggodonuts from over stressing the bird or losing control at the edge of the envelope. But the 'bus folks go way beyond that, so we have pitch corrections for attitude and bank angle limits and such in the "normal" mode. It is more like a Playstation or old Atari game than the Viper.

So my point is we lowly lite folks had a system ( first fully-electronic FBW in active service with no mechanical back of any sort) that allowed us to fly to the limits of the jet no matter how hard we pulled or rolled or.... As with the 'bus, our operational/mission requirements ruled. I will grant that we had a vastly expanded flight envelope ( big time), but the intent and the implementaiton was almost the same.

The biggest difference was our degraded mode. We had only one, and that was there in case we lost air data or selected alternate flaps!!! It used fixed values for the "gains" depending upon the gear handle position. So you can see why I got interested in AF447. Our back up was almost transparent, and we did not lose all the other "goodeis" that the 'bus has because we didn't have them at the outset. The deep stall override function was not considered a back up mode, but it was direct command of the stabilators as the 'bus has in "direct".

So that's my story, and I am stickin' to it.
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Old 5th Dec 2014, 07:35
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@ gums

A very interesting comparison between the AB and the military perspective of the time. In real-life, it also displays the disparity between the "gun slingers" and the "craddle carriers".

The important difference, is that those that flew the "gums era" FBW were actually aware of their aircraft's limitations, and acted accordingly. Hopefully, a new era is upon us where those involved in air transport ops will also have the same awareness.

Thanks again for your little bits of "Viper" reminiscences.
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Old 5th Dec 2014, 14:28
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mm43,
I wonder if the "new" military "gun slingers" are moving closer to the "cradle carriers" in some respects rather than vice-versa:

KenV Post #247 F35C first deck landing:

The F-35 (like the F-16) is fly by wire all the time. There is no back up mechanical flight control system. If the computers go away or the wiring goes away, flight control goes away. And in the case of the F-35 "flight control" includes the engine. The engine is integrated into the F-35's flight control system.

However, there are different FBW "normal" modes and different "degraded" modes. The "manual" degraded mode does NOT mean it reverts to some kind of mechanical sytem of control. "Manual" means that the feed-back motors in the stick and throttle are gone so the pilot flies wihout any tactile feedback. Only the pilot's eyes and "seat of the pants" provide feedback as to what the flight control computers are doing. Basically in "manual" mode the F-35 flies somewhat like an F-16. No stick feedback about what the computers are doing with the control surfaces. But unlike the F-16, the F-35 flight control computers also completely control the engine. When in "manual" mode the pilot gets no throttle feedback what the flight control conputers are doing with the engine. So the "manual" mode of the F-35 is sort of like all FBW Airbus aircraft in "normal" mode with the autothrottle engaged. It is completely computer controlled with no stick and no throttle feedback. Which means that if there is a massive computer failure in the F-35 , there is only one option: the ejection seat.
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Old 5th Dec 2014, 20:23
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Following industry reflexion, Boeing has modified his UAS procedure on all types. Implementation has been progressive in the last year and a half.

They also revised approach to stall and stall recovery. All types

They also gave caution advise for using PLI = pitch limit indication and FPV flight path vector. 777

Last edited by VNAV PATH; 5th Dec 2014 at 20:41. Reason: Added last sentence
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Old 5th Dec 2014, 21:16
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Thumbs up Thanks

Absolutely. Thanks for your true approach of problem.
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Old 6th Dec 2014, 12:49
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well or not well..

@winnerhofer :


Amended "stall recovery" maneuver on all Boeing aircraft types changed early 2011. (2009 + 2)

Actually not directly UAS related, but more widely to global surveys of these problems.


PS : you should quit real estate... I read all this topic, but where you talking of an aircraft or a flying computer ? My comment obviously sarcastic .. but not as much as ..

Last edited by VNAV PATH; 6th Dec 2014 at 12:54. Reason: orthograh
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Old 6th Dec 2014, 16:26
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"stallproof" poof!

Yep, the cosmic FBW system and all its "potections" will prevent stalling the jet. Right. Well...... maybe due to excessive pilot control inputs in "normal" law and fairly benign pitch and roll attitudes.

So over 35 years ago, our small group learned that you could, indeed, stall the F-16, despite all of its "protections". One way was to command max roll rate while at a high AoA and an assymetric load ( think a thousand pounder on one wing and nothing on the other, and a jet that weighs about 22,000 pounds in basic combat mode). So the sucker would depart controlled flight, and the rudder/anti-spin logic resulted in a quick recovery. I actually did a tail slide one day due to a stoopid maneuver while looking at the "bandit". Straight up and got too slow for effective control surfaces. I just let the thing fall over and waited. Sucker came right out once speed got above 100 knots or so.

Our "deep stall" ( not deeply stalled as AF447) mode had the same entry conditions and pilot inputs as AF447. Although we had a dramatically higher pitch attitude, the process was identical. Command a pitch attitude and have the jet lose energy faster than thrust can overcome. As with the 'bus that night, the thing would settle into a fairly gentle "falling leaf" mode. Unlike the 'bus, we had to use a manual mode fo the stabilator, as we had no pitch down authority, but plenty of pitch up authority. So "rock" the pitch attitude and a cycle or two later the nose came down long enough to get effective control.

The big difference in our system was it believed the AoA!! It did this if our pitot-static system went awry. It used the last AoA probe that showed "movement" if the other two were static or frozen.

PJ's war story about his checkout using otto for 90% of the profile scares the hell outta me. I can understand the emphasis upon all the things otto can do, will do, is supposed to do. But first ya gotta learn to fly the plane, huh?

The new jets with FBW are easy to fly, regardless of what features otto has. There's no reason to avoid flying the things "manually", IMHO. It keeps you in the loop, and the Asiana crash shows the result of assuming otto is taking care of business except for pointing the nose.

I do not like the 'bus throttle implementation that has no feedback in most modes. Throttle should move if otto commands the engines to change thrust. The new F-35 has a similar mode for the vertical landing process, admittedly an unusual aircraft maneuver, and the FBW system controls actual thrust according to stick and throttle inputs. Hit the big "mode" button and now throttle controls forward or backward, while stick controls up or down or left/right. Whew!!! Lots easier than the Harrier. The biggie is that the F-35 stick and throttle have "force feedback" determined by control surface load and engine thrust. So you know that you have reached the limits of what otto is trying to do for you.

All for know - poof!
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Old 6th Dec 2014, 17:14
  #816 (permalink)  
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gums, re, "PJ's war story about his checkout using otto for 90% of the profile scares the hell outta me. I can understand the emphasis upon all the things otto can do, will do, is supposed to do. But first ya gotta learn to fly the plane, huh?"

Well, at the time it wasn't worrying because we knew how to fly transports; we knew high-altitude, swept-wing flight from experience having flown the DC8, DC9, B727 and whatnot so learning the automation was a natural progression.

That was then and now is now, and we have been witnessing the results of that largely-unexamined training policy/priority and yes, it concerns me greatly, otherwise quite frankly I wouldn't be spending time writing about it so often - I believe here we are speaking to a great many new pilots who know less about flying an aircraft than they do about automation, (I hope I am wrong), and so hopefully this discussion from the old guys who truly believe have something to say in this instance, will have some effect in what I consider a very real and pressing problem in our industry, (and in others as they permit their professional responsibilities to be removed to the software engineers' desks).

It is a matter of record that as pilots we brought these issues to the fore decades ago, but the problem was essentially invisible to those governing the industry until AF447 and a few other stall accidents. The difficulty faced is the inertia generated by an entire generation focussed on the magenta line, so to speak.

The individual "testimonials" offered are less relevant than the shift in thinking regarding how automation must serve and not rule or supplant our thinking. That is traditionally a very difficult area for those who are primarily aviators or airline management to think in and do something about.

mm43, re, " Hopefully, a new era is upon us where those involved in air transport ops will also have the same awareness.", I am hopeful too and I see changes but nowhere near sufficient to counter the "vector" that automation has taken us. We are infatuated with technique at the expense of, and which has displaced "the art".
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Old 6th Dec 2014, 18:18
  #817 (permalink)  
 
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A profficiency/philosophy thread?

I could not agree more with 99% of PJ's thots and opinions. All accrued from thousands of hours ( but prolly less landings than I had with 4,000 hours in lites, heh heh).

Perhaps we need a new thread to air out philosophy and "war stories" and such.

The F-16 was the first USAF jet that a teen age Atari troop could fly with zero knowledge of aerodynamics or anything. Remember, our cosmic system would prevent stalls or pulling too hard or.... We were very concerned about the newbies, and I was the dude that had to develop and conduct the academic training for them.

Well. the fact of the matter was all the brown bars had flown "normal" planes and we only had to remind them that they could not get away with murder exploiting our neat system. So most training was about navigation and tactics, and not how to fly the jet.

Sounds like the new transport checkout concentrates on systems management like we did back in the early 70's in the A-7D and then in the 80's with the Viper and Eagle and Hornet. The big, really big difference for us was that the mission-critical phases of flight required basic airmanship and were not automated.

Thots about a new thread?
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Old 6th Dec 2014, 23:07
  #818 (permalink)  
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gums, I'll chime in with some thoughts - see how it goes...I'm quite open to starting a new thread, but if I may...

It seems that the AF447 accident attracts these kinds of discussions; - twelve thread's worth in fact! We might even say they're the "go-to" or perhaps the springboard when discussing the kinds of human factors and technical aspects of aircraft automation that this accident in particular, has highlighted and that they're applicable to a wide range of technical and engineering endeavours. We can include the notion of competency, and what it looks like (because it is certainly changing!). What I like about staying on the AF447 threads is that those who may be seeking the lessons from this and other, similar accidents know that this is the place to come.

I''m particularly concerned that those who manage large aviation organizations who may or may not actually fly and who may drop in to PPRuNe will click on "AF447" and begin reading a discussion that is both directly related to their oversight responsibilities and has broader lessons to offer those who have grown up with software/hardware/firmware "solutions" to commercial flight and may not be aware of the "principles of aviation".

I think it is fair to agree that the carrier involved in the accident has lessons for all carriers and operations, both military and commercial, large and small. The mark of a "just culture" is the willingness to discuss such issues with a view to taking the lesson without judgement, for judgement in aviation will always make a fool of one, eventually. The reason why is simple - many carriers are still not learning from others' mistakes...

I have heard first-hand the comment from pilot-managers that their carrier was "beyond an accident" as they had "learned the lessons". I have heard comments that their fleet type doesn't need flight data analysis, for example, because, unlike other fleets (which did have flight data analysis and had "events"), their pilots were good and followed the SOPs and nothing was being reported. Seriously - I have heard this. I am quite sure things have changed since then; I hope so.

Such attitudes are, in and of themselves, precursors to an event. Such attitudes would have a corporate history and a "supporting cast" where groupthink and the value of "concensus" are the unwritten rules by which one maintains one's position within the organization, and who may not even know that their tolerance of such statements fosters the normalization of deviance and a culture of enhanced risk.

I think those interested in finding ways to recognize and possibly change their airline's culture may visit something to do with "AF447" because of the well-known human factors and organizational issues behind the accident. While I believe strongly in the examination of ideas, (philosophy) and also in hangar-flying, not everyone may gravitate to a discussion which would be, in my view, a very worthwhile thread but which value may not be immediately apparent. Despite the contributions wishing to persuade readers one way or another regarding the legal or technical specifics of the causes of the AF447 accident, these twelve threads hold a treasure-trove of experience for new players, in both cockpit and the office.

For most, the lessons of AF447 are now quite far beyond the actual accident itself, and the value of such discussions from contributors who know their stuff and have lived it and can write, like gums for example, is immeasurable for those with eyes and ears and a strong keeness and skepticism.
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Old 8th Dec 2014, 13:20
  #819 (permalink)  
 
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Here's a thought:

It's been about 5 and a half years since AF 447 went down.
Been about three years since the recovery of enough information to understand why.

What has changed?
a. In the industry?
b. In that company?

As I understand it, there was a review/renewal of how to proceed when all three air speed indicators go on holiday at once. (But then, the Pitch and Power chorus already had that answer before the aircraft itself was pulled out of the ocean).

I also understand that upset training has gotten more support.

Does anyone have a sense of the answers to a and b beyond those two points I have there?
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Old 8th Dec 2014, 13:25
  #820 (permalink)  
 
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Improved equipment, installation of BUSS on airbus aircraft.
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