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New technologies, reason for accidents...?

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Old 28th Jul 2007, 22:21
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New technologies, reason for accidents...?

Gentlemen...
xxx
For the past few weeks, I have enjoyed reading the forums, and educated myself with the new generation pilots and airplanes they fly. Being now near retirement, I wonder if all that is good to the industry and flight safety...?
xxx
Some examples here -
xxx
Nowadays, with extremely accurate GPS precision navigation, and extremely accurate altitude control of RVSM airplanes, when we are "on track" and "at FL xxx", we are really there, not half-a-mile to the left and to the right of track, and not 50 feet above or below our assigned levels... But is precision a source of accidents, in terms of human lives...?
xxx
Months ago, I read with horror about the mid-air over Brazil, an airspace I know well, of the Embraer Legacy, and the Gol 737... The two planes were modern airplanes, equipped with GPS navigation system precision, and RVSM standards. Maybe if they would not have that precision, there would have been no mid-air, just a "near-miss" incident...
xxx
I will admit a voluntary airspace violation I did often in my life, back in the past when flying in some "nearly or completely uncontrolled" areas of the world, such as Africa, Asia or some parts of the South American continent or oceanic areas... My violation is/was to select 200/300 feet OFF the assigned FL, on the autopilot altitude hold selector... I know why I did such thing, as recently as 7 years ago, flying from Europe to South Africa, where ATC and radar is quasi inexistant...
xxx
Half of the pilots "would never do such a thing"... (the "Geeks", the "Nerds" and "Goody-two-shoes" types) and "half of us", (like myself) might have done that. Unknown to me, maybe, I avoided a few mid-airs, by missing other flights by 200 feet, above or below... Not my invention, I learned from the "old timers" I respected
xxx
Another example, about FADEC or equivalent power limiting systems for engines... In a recent thread, I questioned the inability of a well qualified and experienced test pilot of a A320, in France, who, making a low pass, gear down at an airshow, was unable to "overboost" his engines to recover from a low altitude and high drag situation, and ended his flight in the trees, with numerous victims. His FADEC system saved the engines from overhaul, but the victims could not be overhauled...
xxx
Finally, I am at awe, reading about these pilots "forced" or "induced" to use automatic landing system as SOP on all approaches they perform. Where do they acquire "airmanship"... Is it by depressing a few little buttons and moving switches...?
xxx
I appreciate the level of assistance I have in old (soon to be retired as well 747-200s) provided by triple channel Cat.II and Cat.IIIA capable autopilots, but I have tried to preserve my ability to fly an approach and landing manually, unless visibility/conditions did not permit, or if tired at the end of a very long day, or night...
xxx
So, new technologies, but I do not believe it does increase safety, and certainly does not contribute to promote or maintain airmanship. I am curious to read those who will oppose my pont of view... (or share it) -
xxx

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Old 29th Jul 2007, 14:23
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I have to agree with you. While talking about Dash 8 operation only, I remember the days before FMS / GPS when two flights on the same airway would never cross directly over/under each other,a few miles horizontally being the norm. It's quite common today and makes me wonder about an incorrect altitude - either by ATC or Crew - causing a head-on collision (OK, probably won't happen with TCAS - but is this more machine dependancy?).
As to automation, I find that most new hires are too dependant on the FD and AP. They have to be prompted to do a bit of hand flying - and most of them need it. Not forgetting the veterans who become lulled into complacency by the gadgets.
Don't get me wrong, when the weather is kicking, I'll use everything available and the automation makes my job alot easier, but on those clear days it's real nice to hand fly a raw data ILS.
So, is safety improved by the new technologies? Definitely yes - but when the technology fails, we will have to rely on skills that have gone rusty due to the new technologies.
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Old 29th Jul 2007, 15:23
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BelArg -
Another example, about FADEC or equivalent power limiting systems for engines...
- to pick up on just one of your points, I think that if you study the findings of the Habsheim accident you will find that 'overboosting' would have made no difference to the outcome. It was spool-up time from idle that was the 'killer', and the fly-by-wire did its job perfectly in refusing to allow any significant raising of the nose due to lack of performance. Result - the a/c settled into the trees, but WINGS LEVEL. There is always the possibility that on a non FBW a/c the 'panic' pull back on the c/column could have caused a wing drop and roll which would probably have killed lots of pax?

The a/c kit said 'No'! We will never know whether there really WAS enough energy to lift the a/c those few feet.
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Old 29th Jul 2007, 15:39
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I once read in 'HANDLING BIG JETS' by its great author of a scheme to restore those [rusty flying skills]
A major airline..can either own or lease a small jet, such as a learjet and train their pilots in recovery from unusual attitudes since most of them hae forgotten how to fly an aircraft as opposed to operate one..what are your thoughts on this idea?
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Old 30th Jul 2007, 00:44
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I believe Singapore Airlines had Learjets to train pilots, at least some time in the past. Also remember PanAm in 1968 had thought of using DA-20 Falcons to do the same thing, but never came to be a fact. So did United, I saw pictures of a Falcon 20 with PanAm colors, and a Learjet 23 in United markings...
xxx
Learjet (particularly old 20 series) are excellent "jet trainers" and all new hires I have seen with that aircraft background do a good job in airline training environment. These old Lears are not easy planes to handle, and can kill you if you dont watch-out...
xxx
The CEO of "an airline that I know well" has the use of a Learjet 31A, but that is just to enjoy nice company while flying to exclusive resorts... I dont think he likes the service in F class of his own airline, or the schedules... Good excuses...
xxx

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Old 30th Jul 2007, 03:15
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An intresting idea, bflyer, but one to be approached with a great degree of caution.

One must avoid imparting negative training when using a scheme like that, and that is very difficult to do! Upset recovery techniques can vary widely, especially in the FBW world, and the last thing that we want is a crew in an Airbus not burying the stick aft to avoid terrain because some small part of their subconscious is linked to a Lear jet where that would overstress the aircraft. The law of primacy comes into play strongly here.

Upset recovery training itself can be a double edged sword - let us not forget the lessons of AA over New York in an A300/310. While certainly not the consensus, there is a feeling among many that the upset recovery training provided to the crew was a major contributor to the accident.

The lesson always seems to be this: know your aircraft, be it an A340 or a Sopwith Camel. Know its systems, its automation, and most importantly its limits. Know the SOPs cold, and keep up to date with the latest regs (i.e. strategic lateral offsets - deliberately flying slightly offset in certain airspace as described by the original poster).
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Old 30th Jul 2007, 09:25
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Spool up time etc...

Hola BOAC -
xxx
I agree with you that the Habsheim accident was probably due to the factor of spool-up time, and combined with other factors, such as a lower altitude than planned. Apparently, the pilot was not even familiar with the airfield environment, but I still believe that the concept of the A-320 technology may be a difficult transition for the flight crews of my generation.
xxx
When I started as airline pilot, numerous captains were ex DC-6/7 pilots, some who had a difficult time to adapt to the 727 jet transports. I remember a notorious accident (UAL 727, Salt Lake City, mid-1960s) that was often cited as example in classroom discussions, about the factors when transitioning pilots from one generation of aircraft to the next. The spool-up time of a R-2800 or R-3350 was different than a JT3D or JT8D...
xxx
I found myself in the same situation a few years ago when the first airplanes appeared with "glass cockpits" and FMS equipment, and I refused to transition to such airplanes. Same with a reduction of flight crews from 3 cockpit crewmembers down to the 2 pilots as we often have nowadays.
xxx
A few years ago, our 747 pilot group (and myself) fought a war with our management to select 747-300s rather than more expensive 747-400s... The issue was supression of the flight engineers, and the extra range offered by the 400 series (very little range increase, which was not even warranted for our sectors). The price of the 300s was approximately $10-12 million per unit, instead of $30-35 million for the 400s... Passenger capacity was same for both aircraft types. The major issue was then the flight engineers. The company politics at the time was worsened by the economic situation in Argentina in 2001-2002, and averting the bankruptcy of the airline... The proponents of the 747-400s won the battle... They acquired 4 747-400s from Canada, and spent a fortune in crew training, while no training would have been required if they had acquired the 747-300s...
xxx
What made us smile, however, our unions demanded that flight engineers be trained to be "cruise first officers", and that all first officers be qualified as "cruise captains" with P-1 type rating...
xxx
At the end... our 747-400 sectors are long, all requiring a crew of three pilots, but now, that crew of 3 pilots have a higher salary, than the crew of 3 (2 pilots + F/E) in the 747-200/300s... So, our accountants selected an airplane... with higher crew costs...
xxx
Airline managements know little about airplanes...

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Old 30th Jul 2007, 11:03
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The a/c kit said 'No'!
I have a pair of piston engines and CSUs designed in the 1950s (if not earlier). Even when I push the blue levers as hard as I can against the stops, the "a/c kit" says "No!" and stops me from getting more than 2700 RPM, even though I know the engines can turn faster in an emergency. Damned new technology...
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Old 30th Jul 2007, 11:24
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power curves and spool

I dont know much about reciprocating engines, just remember a few questions from an ATPL written with some DC-7 questions...
xxx
Power available was not RPM only, but BMEP as well... Then on top of that, I remember the propeller slipstream on the wing reducing stall speeds... and immediate power increase available, not the case of jets from idle power...
xxx
If I remember well, an Allison J-33 engine or RR Nene had something like 30 seconds spool-up time from idle to max power...? Probably was hard for the Mustang P-51 or Spitfire pilots to live with that difference when transitioning to F-86s Sabres or Gloster Meteors...
xxx
Flying a prop airplane, and transition to jets WAS difficult...

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Old 30th Jul 2007, 12:15
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BelArg,

Regarding accuracy of modern nav systems, the solution is to offset where possible.

For example, see
http://http://www.pprune.org/forums/...d.php?t=286071
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Old 30th Jul 2007, 14:46
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If I remember well, an Allison J-33 engine or RR Nene had something like 30 seconds spool-up time from idle to max power...?
I don't know about the Allison, but I flew the Nene powered single seat Vampires and spool up time on a touch and go was quite fast -around 5-8 seconds from idle to full power. The dual Vampire Mk 33 with a Goblin wasn't too bad either although if you pushed open the throttle too fast the engine made loud rumbling noises.

Regarding the observations on reluctance of pilots (SOP maybe) to switch off the flight directors and automatics. From listening to countless stories of my former simulator students now happily flying jets as first officers, I was surprised to hear that most of them would love to be able to hand fly raw data but their captains are often reluctant to let them do this. All sorts of reasons are offered for this reluctance but it boils down to the fact the captains were themselves rusty at real handling (as against letting the automatics do the lot).

There are plenty of willing young first officers out there who would like to dare to switch of the FD in a climb or descent - but the left seat bloke won't allow them the pleasure. It's all about the "twitch factor."
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Old 30th Jul 2007, 20:47
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Y did it do that?OR: Automation, do we need it?

This thread is to speak out on the concepts of automation in the cockpit.

About 15 years ago, I met a chap who was / is on the boeing chair at MIT (important technical university near boston, usa).

He said that the days of the skilled pilot were gone and that anyone with 300 hours or so would be able to handle the new computerized jet airliners.

With the thread about the TAM crash already at 737 posts (hmmm 737), I thought I would shift talk about automation and the man/machine interface to this spot.


Time to speak up or out on this subject.


Those of you who know me will probably understand that I would prefer a simple jet with less automation and more skill by the pilot.
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Old 30th Jul 2007, 21:07
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There was at one time a significant theory about the human capability to operate within the well-designed loop, versus his ability to effectively, long-term, monitor a control loop operating autonomously.

The evidence at that time was seen to support the former rather than the latter. There were some theories postulated why this should be true, including evolutionary processes, that favor the "doer" over the "watcher" role for mere mortals.

What is the current thinking in this regard? Airbus particularly seems to have departed from this quasiparadigm (if you'll pardon my vocabulary).
The insurance industry must have some opinion one way or the other.
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Old 31st Jul 2007, 02:19
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Good on ya!

BelArgUSA has just posted the basic concept of many, many 'decisions' that were being made a couple of years ago.

Many times the decision to bypass the B747-300 is totally based on things other than the efficient economics of operating a v/large aeroplane.

Like QF and AP!

It has been, and will always remain, that I believe that the B747-300 is by far the best jumbo aircraft ever made, bar none (including the oncoming!).

This is inline with my ongoing dogma that I believe going to 2 pilot crews on v/large airplanes, versus the 3 crew (2+1), was and remains a very questionable decision!

Cheers...FD...
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Old 31st Jul 2007, 20:59
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I found the transition from the MD80 to the 737 200 much more difficult than years before going from the 737 200 to the MD80 in the right seat. Learning automation and still having your manual skills intact is easier than losing your hands on flying skills because of auto everything and having to do everything yourself again.

I ended my career in the B757 flying manual approaches rather than going to the B777 so I could enjoy the last few years. No stress, no surprises.
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Old 1st Aug 2007, 01:21
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BelArgUSA, I think you might enjoy this book Air Disaster Vol 3 by Macarthur Job. Mac Job is a former australian air safety investigator that has a talent for exploring the issues behind accidents and communicating them to us.

Chapter 1 deals with the AirFrance A320 in 1988. Interestingly on that occasion the engines spooled up as commanded, in fact faster than manufacturer data.

It is an interesting read. I recommend it to you!

ITCZ
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Old 1st Aug 2007, 12:41
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Chapter 1 deals with the AirFrance A320 in 1988. Interestingly on that occasion the engines spooled up as commanded, in fact faster than manufacturer data.
The obvious corollary is that the command came too late.
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Old 1st Aug 2007, 15:07
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Indeed.
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Old 3rd Aug 2007, 15:55
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Question Auto-thrust, auto brake, auto spoilers . . . . .

Background (for those who do not know me) - Built sims for Singer-Link (-Miles) and maintained sims for BA (VC-10, 707, 747 Classic, and 737-"just")

Scenario - Aircraft happily rolling down the ILS (maybe in A/P or maybe hand-flown) - passes 100ft (?) and auto knocked off, pilot continues landing, shutting the power as the aircraft flares and touches down, spoilers (manually) deployed and thrust levers lifted up into reverse and brakes applied.

Can somebody please tell me what was wrong with this story (minor details maybe as it was years ago for me)

Now it appears that almost everything above is carried out by The Computer (okay -lesson the Boeing, but still some of it). Is it hard to remember "flare, power off, spoilers, reverse, brakes" (sharing some of those with your colleague)? So why hand over the control of the aircraft to The Computer?

Not that I have any problem with the autopilot systems - flying an 8-hour leg across the Atlantic must have been pretty tiring and boring (hopefully) - but why do we now seem to be handing most, if not all of the authority to a machine? Especially those critical phases of the flight

I remember in the latter days of my airline career doing a "route-fam" in a BA 737 to Spain and back - on arriving at LGW asked the crew if they were going to approach on A/P and getting the answer "no, it's a lovely clear day and we probably need the practice" !! The PF (left seat) held those 2 yellow bars glued beautifully in the centre all the way down with no problem!

Why does it seem to me that the automation is taking over the aircraft, complicating its operation (?), and depriving the crews (?) of the everyday "stick and rudder" practice? (in some aircraft,even depriving them of the stick completely)

I know that commercial flying gets safer every decade, but are we not forgetting the valuable input from the well-trained professionals who inhabit "row -1"?

(post inspired by the recent TAM and other similar instances)
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Old 4th Aug 2007, 15:52
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Scenario - Aircraft happily rolling down the ILS (maybe in A/P or maybe hand-flown) - passes 100ft (?) and auto knocked off, pilot continues landing, shutting the power as the aircraft flares and touches down, spoilers (manually) deployed and thrust levers lifted up into reverse and brakes applied.

Can somebody please tell me what was wrong with this story (minor details maybe as it was years ago for me)

Now it appears that almost everything above is carried out by The Computer (okay -lesson the Boeing, but still some of it). Is it hard to remember "flare, power off, spoilers, reverse, brakes" (sharing some of those with your colleague)? So why hand over the control of the aircraft to The Computer?

This scenario happens to this day, except perhaps for the auto ground spoilers bit. Auto brakes and auto spoilers have been around for an awful long time and were integral to the hands on aircraft people seem to yearn after. I'm not aware of any current aircraft with auto thrust reverse. Ground spoilers can be manually deployed if the auto system(s) fail.

Auto brakes are a great benefit, both in reducing maintenance cost but also increase safety. It doesn't make sense to manually brake AND have to be using the rudders to control the aircraft during rollout. Auto everytime.

No one forces pilots to auto-land all the time. AFAIK most landings (and ALL takeoffs) are manual, of only in the last 500 feet. An A320 is very pleasant to hand fly as it happens (at least that is what I have found flying the simulator, not being a pilot).

FADEC gives the pilot care-free engine operation. It is found on some quite elderly aircraft, not just Airbuses. In the "good old days" rough handling of the engine might result in a catastrophic failure. Even pre-FADEC some engine manufacturers (e.g. RR) had limiters on everything so over-boosting simply was not possible. I can't think of a single good reason why FADEC could be a "bad thing".

The automatics are there to help the pilot and improve safety. There aren't too many instances where they have caused accidents, and even then it is usually because the "operator", (aka the pilot), misread indications or was over reliant on auto modes when the situation demanded otherwise. They can reduce situational awareness I suppose, but good training should take care of that.
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