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Flight Directors - a sometimes fatal attraction

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Flight Directors - a sometimes fatal attraction

Old 5th Feb 2013, 16:22
  #41 (permalink)  
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westhawk;

Re, "I've heard this technique referred to as "looking through the FD" too."

Yes, that's exactly what it was/is. That applies today, even on Airbus aircraft.

The best demonstration of this phenomenon is (in the sim), flying a raw-data ILS in poor vis or at night with a bit of wind/turbulence.

While it can be done quite well, if one isn't practiced at it, keeping the LOC and GS centered presents quite a challenge.

However, with the FDs on, one "subliminally" sees the movement of the FD and "anticipates" in the manner you described, making the job a lot easier. One is still "flying through" the FDs, focusing on the small pitch, roll and heading changes as they affect the ILS indications but the FDs are of significant assistance if one uses them this way.

Again, the Airbus FDs are indicating what the autoflight would do if engaged and so appear (but are not actually as this is just software, not a human being!), "anticipatory" in that the autoflight system (and therefore the FD system) senses imperceptible deflections of the ILS and the actual PFD indications are smaller than may be initially perceived by the PF - but the FDs respond and their deflections are visible and so can help maintain the flight path, without "leading" the pilot on a leash...so to speak.

"Looking through" the FD requires time to learn; it doesn't mean one is ignoring the FDs, it means that their indications are appropriately "psychologically placed" and used at various learned levels of awareness. In my view they aren't, in the end, necessary, but they are an enormous aid in many though not all circumstances.

One tends to ignore the FDs, (looking past them and not just through) in transient moments of energy changes where the FDs do not know what is coming next but the pilot does, or should! In my view, the most important example for understanding this is the AF 447 accident.
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Old 5th Feb 2013, 22:39
  #42 (permalink)  
 
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I was departing KLAS to the west and once above the terrain I clicked all three off.
I don't mean to criticise you personally Ttex600 because I don't know what else was said. But hypothetically, if manual flying is uncommon at an airline, and a capt decides to do some raw data flying without any verbal preamble at all, I'd be a little scared too. Not of the aircraft, but of what other random ideas the guy to my left is going to throw into the cockpit without warning.

Not every reticent FO is a child of the magenta line. The conversations that captains foster, are the most useful learning tool for me.
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Old 6th Feb 2013, 01:28
  #43 (permalink)  
 
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Any pilot that can not hand fly an approach easily should not be flying an airplane in my opinion. They should not be allowed in the cockpit. What do you think if automation quits?
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Old 6th Feb 2013, 01:35
  #44 (permalink)  
 
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Automation is making pilots not pilots but programmers. We need to fix this. Pilots that can not fly without automation are dangerous. AF 447 showed that, neither one knew how to hand fly. The only qualified pilot was taking his rest break.
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Old 6th Feb 2013, 03:42
  #45 (permalink)  
 
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As a "light" pilot with a few thousand hours in single-seat jets, I am wondering how the "flight director" displays are supposed to work.

I never flew a jet for a long time that had the same "flight director" stuff that folks in the T-38 had. So I had been trained in the T-33 and such.

Our primitive flight director stuff was a needle on the large ADI and was only for heading/course interception of a radial or the ILS centerline. Crude, back in 60's, but decent. Then to the A-7D and same old flight director gizmo needle on the ADI that I had not seen, being a T-33 troop back in 1965.

The best thing I ever saw was the A-7's flight path marker in our HUD. Not familiar to many here from the "commercial" community, seems to me. You could see the exact place where the jet was going - not attitude, but actual flight path with respect to local level, or the Earth.

As with many here, I agree that the pilots must demonstrate "basic" instrument and visual flying competence, regardless of all the "aids" and "commands" and such.
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Old 7th Feb 2013, 02:18
  #46 (permalink)  
 
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Originally Posted by Oktas8

I don't mean to criticise you personally Ttex600 because I don't know what else was said. But hypothetically, if manual flying is uncommon at an airline, and a capt decides to do some raw data flying without any verbal preamble at all, I'd be a little scared too. Not of the aircraft, but of what other random ideas the guy to my left is going to throw into the cockpit without warning.

Not every reticent FO is a child of the magenta line. The conversations that captains foster, are the most useful learning tool for me.
My carrier employs a far greater percentage of "cowboy" pilots than almost any other jet transport aircraft flying airline in existence. A lot of pilots, maybe not a majority but a significant number, handfly often. Turning the FD's off is about all I can find to explain his concerns.

He was briefed BTW, and in exactly the same briefing that I gave him permission and encouragement to to the same.

PS. The top third of our sen list were/are all high time DC9 Captains with a large percentage of us originating in a Learjet night freight environment. I'm certain that hand flying is quite common. Hope that sheds a bit more light.

Last edited by TTex600; 7th Feb 2013 at 02:30. Reason: Add explanation
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Old 7th Feb 2013, 02:24
  #47 (permalink)  
 
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Originally Posted by RAT 5

I suspect your real name is Richard Bach and you have a novel hidden inside you bursting to get out.
Sorry to disappoint. It happened. Take it or leave it.
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Old 7th Feb 2013, 02:41
  #48 (permalink)  
 
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Originally Posted by PJ2 View Post
Like any computer, it has no "reason" for doing something - it doesn't "know" why it is doing something because the design is "hard-wired", but we are not.
If I may nitpick a little - while the process is indeed hard-wired, the output could be considered as a process of "reason[ing]" and "know[ledge]". Where you're absolutely correct is that the results of said process are only as good as the data being fed into it, as well as the fact that the artificial reasoning process is by its very nature circumscribed in terms of what it can handle. This is why modern autoflight systems are designed so that they will not only disengage if those parameters are exceeded, but will also not permit re-engagement until those parameters are returned to within those limits.

The human brain is infinitely better at recognising and coping with such abnormal situations, and that fact underpins the notion that electronic aids like the FD should never be trusted blindly - if it looks wrong, it probably is.

Airbus recognizes this by stating that if you don't intend to follow the FDs, turn them both off.
As do Boeing, and probably most if not all of the others.

Originally Posted by petitb View Post
I think a big problem lies in the (apparent) Airbus philosophy which seems to advertise it's aeroplanes as ultra safe and if the automation is used throughout, the aeroplane "will fly itself" and you are protected throughout the flight regime.
That's a common misconception. Airbus's FMC/autoflight setup is no more complicated or clever than anyone else's. Envelope protection is a feature of both Airbus and Boeing's FBW systems (albeit implemented differently), and with apologies for sounding like a broken record, do not confuse FBW with automation!

The industry-wide push for adoption of automation originated with the airlines, not with Airbus, or for that matter, any other manufacturer. PJ2 wrote a wonderfully concise post a while back on the encroachment of the MBA generation on airline management, and now as then I concur completely with his assessment.
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Old 7th Feb 2013, 02:51
  #49 (permalink)  
 
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If you can't fly without FD command bars you end up like AF447. Make sure you agree with what they are telling you before blindly following them. You shouldn't need them if you are a real pilot so why follow them if they are wrong?

I won't repeat the flight with the check airman totally screwing up my FD so I ignored it and flew our clearance raw data until he caught up. It was go into a diving left turn or a climbing right turn which was our clearance. He finally caught up. He was checking me out as a 767 captain. He never said a word about his screw up. I passed and everybody was happy.
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Old 7th Feb 2013, 16:07
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Tex600: I believe it did. I hope you didn't take any offence, or anything else
-ve, none intended. It was more complimentary than anything else. Good heart-warming stories here are hard to find.
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Old 7th Feb 2013, 23:43
  #51 (permalink)  
 
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I never turn the FD off. Hand fly every departure and most arrivals below 10,000'. At some point hand flying at higher altitudes is not teaching an experienced pilot anything. New guys? Sure, learn the difference in pitch sensitivity as altitude and mach increase. Old timers? Waste of time and effort.

Sometimes during high work load departures/arrivals, like thunderstorms, AP might be used to decrease workload as necessary. That's what it's there for, a balance of workload vs. manual skills maintenance.

Do I USE the FD all the time? No. Ignore it when necessary("look past"). It's not that tough.

SOP requires FD on for takeoff. Boeing - "the FD pitch command is not used for rotation." In other words, you have to look past it.

Last edited by misd-agin; 7th Feb 2013 at 23:45.
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Old 7th Feb 2013, 23:53
  #52 (permalink)  
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Waste of time and effort.

Even if those of us who prefer short sectors to forever and a day passage making find it great fun and, right or wrong, believe that it assists in maintaining that je ne sais quoi hands on finesse nicety.
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Old 8th Feb 2013, 04:45
  #53 (permalink)  
 
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I never turn the FD off. Hand fly every departure and most arrivals below 10,000'. At some point hand flying at higher altitudes is not teaching an experienced pilot anything. New guys? Sure, learn the difference in pitch sensitivity as altitude and mach increase. Old timers? Waste of time and effort.
"Never turn the FD off" ? "Hand fly every departure and most arrivals below 10,000." Horses for courses. Enthusiastic pilots will normally jump at the opportunity to switch of the FD and hand fly where possible. Keeps the instrument scan skills honed. On the other hand it could be argued a complete waste of time hand flying while glueing your concentration on a FD. Isn't this what the original post was all about?

As far as practicing hand flying at high altitudes, if the two French first officers that crashed the A330 into the South Atlantic has ever practiced hand flying at high altitude either in real life or in the simulator, it is probable 200 plus people would be alive today. if a pilot cannot confidently hand fly straight and level at high altitude because it might upset the passengers coffee then what an indictment on the company training system. Old timers waste of time and effort? Don't you believe it. Mostly they are too lazy and know they lack the confidence, finesse and handling skills needed to fly smoothly and accurately at high altitude.
But these characters would never ever admit it but are quick to denigrate those pilots who have the enthusiasm, ability and determination to be on top of their flying.
To clarify. No one is demanding that a pilot should fly for hours by hand with or without the other automatic features such as FD in place. But if people are serious about rectifying what the FAA have finally said after all these years and numerous LOC crashes, that one way to prevent automation addiction (affects maybe 85 percent of glass cockpit crews), then a spot of regular manual flying is the way to fix the problem. 5-10 minutes out of every hour in high level cruise hand flying is better than nothing at all assuming of course the rules permit (RVSM etc).
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Old 8th Feb 2013, 05:26
  #54 (permalink)  
 
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I really think flying manually with the FD on is a total useless exercise,(except maybe for ILS)any monkey could do that.
There is time for the FD and AP to be engaged( RNaV dep..) and time to fly all off...
I have had fos trying to fly through the FD..only thing it does is offtrack during rnav departure...following this see through flying...a FD off AP off is proposed during descent by asking for vectors..most accept,some are persuaded,some dont want.

Last edited by de facto; 8th Feb 2013 at 05:27.
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Old 8th Feb 2013, 19:19
  #55 (permalink)  
 
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In my opinion I think That FD sould be used as an aid to make the job easier, but never ever forget how to fly a plane, as a good captain once said to me "machines tent to brake and a jet is a complex machine that will have some failures", the FD te AP can fail, a pilot must be competent in flying the plane manually, if you can't track a VOR an ILS maintain altitude, attitude, heading, speed, fly any SID STAR or visual approach etc...he sould not be near a plane.
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Old 8th Feb 2013, 21:33
  #56 (permalink)  
 
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Manual flying with a FD is not manual flying because you don't have to scan your instruments. Manual flying is looking at your instruments and using your manual flying skills to accomplish what you are doing. It is simple unless you have no manual flying skills. Then you shouldn't be in the cockpit in the first place.
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Old 9th Feb 2013, 13:25
  #57 (permalink)  
 
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From the onset of training, the trainer should emphasize the FD are nothing more than tool for guidance. During line training, a new pilot will gain better experience and confidence by reinforcing the four fundamentals of flight without the aide of the FDs.

I encourage my F/Os to perform manual flight without A/T or FDs upto RVSM territory and from TOD to landing. 3 for one planning plus X miles for descent and visual approaches when possible. No Pablo Picassos in the FMC for patterns, nor runway extensions for landing.
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Old 9th Feb 2013, 15:45
  #58 (permalink)  
 
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Captjns,

That is all well and good for you're aircraft type and operation.

Mine however, it is prohibited to perform things like FD takeoff. (unless required and in accordance with the MEL)

In all honesty I think on the Airbus types you would be far better of drumming into new pilots the importance of FMA changes and mode awareness.

The automation is there to help us, and make the operation safer and more efficient.

The challenge is to adequately monitor the performance of these systems and to fully understand their objectives and limitations.

Personally flying around with all the kit of in the busy TMA I don't see does anything other than reduce overall SA.
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Old 9th Feb 2013, 17:09
  #59 (permalink)  
 
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Just to lighten up the thread. if anyone can find the link to 'Space Cowboys- Flying brick'. It will bring a smile to your faces. If someone can find a link to post it here it might spread the word. It is in 2 parts; 1st is a 'cock-up', the 2nd is tongue in cheek successful.
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Old 10th Feb 2013, 01:32
  #60 (permalink)  
 
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Pilots that depend on automation are not real pilots.
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