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Flight Directors - a sometimes fatal attraction

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Flight Directors - a sometimes fatal attraction

Old 4th Feb 2013, 07:08
  #21 (permalink)  
PJ2
 
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John - re 'low', it was a short chat, and yes, a pity but next time, a certainty! PJ2
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Old 4th Feb 2013, 08:28
  #22 (permalink)  
 
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When I made the switch from military to commercial aviation, I was doing sim training and the sim instructor kept telling me to "follow the command bars". I responded "those are SUGGESTION bars, I'll do the commanding thank you"
That is outstanding.

Centaurus: excellent writing. I too lament the degradation in basic skills and in despair of some of the things I hear about the new breed.

In the RAAF, power/attitude/trim was the mantra that lead to graduation. Even at Ansett we were expected to know the power and attitude for a few basic manoeuvres.
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Old 4th Feb 2013, 09:06
  #23 (permalink)  
 
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Flight directors, in my opinion, can make you stupid if you forget about raw data. My FO one day was getting very low on an ILS so said you are too low. She said no I am not, my FD says I am high. It was an old 737 and the FD was stuck indicating nose down. Hopefully she is retired now. She did stuff like that a lot. At least we didn't land in the vinyard short of the runway. She left in a huff after landing so wrote up her FD thinking ATC probably got a low altitude alert I would have to explain later.
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Old 4th Feb 2013, 09:32
  #24 (permalink)  
 
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I remember watching an initial A321 type rating sim session with a "child of the magenta line" pilot hand-flying an ILS with F/Ds on, localizer established, flying through the glide because the PM had forgotten to arm APP.

When they realized what had happened they were almost a dot high: instead of simply pitching down and easily recovering the glide (perhaps switching off the F/Ds as per Airbus recommendations) the PF continued faithfully following the F/Ds in level flight, all the while shouting commands at the thoroughly confused PM as to what settings he now wanted on the FCU (MCP in Boeing English). Needless to say by the time they got the F/Ds to command a pitch-down it was too late and the approach became an unstable mess.

YOU fly the airplane, not the automation. If it ain't doing what you want, you fix it, whether with a lower level of automation or by disconnecting everything and (gasp, shock horror) flying the airplane yourself, as a pilot -by definition- should be able to do.

Old grumbling [email protected] rant mode OFF.
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Old 4th Feb 2013, 10:01
  #25 (permalink)  
 
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My check airman did the same thing. He didn't arm app. so flew threw the glide slope. I told him to disconnect everything go to idle power, dirty up and descend back to the now out of sight glide slope and about 1500 ft we broke out approaching glide slope and landed. He wanted to fly the leg but it was late at night and I just wanted to have a couple beers and go to bed and didn't want to go around for no reason except stupidity.
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Old 4th Feb 2013, 14:40
  #26 (permalink)  
 
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Many of the personal recollections / incidents relate to incorrect switching or mode awareness. Switching the FD off should avoid these ‘errors’, but the subsequent manual flight may not help pilots avoid similar problems of switching / awareness where FD or autopilot use is essential; particularly if these are the same issues which the FAA SAFO recommendation refers too (#1).
More manual instrument flight should reinforce skills of scanning and awareness, but its effectiveness will depend on the flight situations encountered. The more demanding tasks (flight-path precision, high workload, mental awareness) during departure or approach are unlikely to be hand flown, nor without FD. This conflict results from the increasing complexity of modern operations, and in what is required or expected of pilots in order to be efficient (but not at the expense of safety).

The recollections / incidents also indicate ineffective cross monitoring. Does the PM check manual flight accuracy with respect to the FD, or in autoflight does the crew rate the autopilot performance according to the FD. Only the aircraft instruments show what is happening (now) vs the FD which indicates what has been selected to happen (future); we shouldn’t check 'now' based on thoughts of the future.
These are potentially hazardous behaviours which may overlook selection mistakes or mode transitions; also they may result in a poor understanding of where the aircraft is going or what the system is attempting to accomplish. These ‘errors’ may be independent of manual flight skills in benign situations.

Monitoring - Plane, Path, People (and self), requires knowledge of a norm, what has been planned, expected, of what is important, and how and when to check a parameter.
This involves discipline, the habit of scanning and comparing via understanding:- what is happening vs what is required. Many of the apparent problems of automatic and manual flight are actually in this understanding.
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Old 4th Feb 2013, 16:38
  #27 (permalink)  
 
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I once asked why my F/O was low on the visual approach - response was, that's what the FDs were saying to do... We had a chat.

When any pilot says they fly the FD religiously I do a simple demo, (in the sim). One is to stall the a/c with FD's centred and the other is fly the a/c into the ground (crash inhibit on) again with the FD's centred. It tends to get their attention, and their understanding.
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Old 4th Feb 2013, 16:58
  #28 (permalink)  
 
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What is a "Flight Director"?

For me, the PF is.

If he/she can't cope with the desired flight path, it's me....
at the very end of the chain, the commander.

Last edited by hetfield; 4th Feb 2013 at 17:30.
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Old 4th Feb 2013, 18:45
  #29 (permalink)  
 
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Cpt Pit

I understand your comments, especially if you're a bus driver. Try following the FDs on the 747-200 classic and you will overshoot the LOC 5 times out of 10 and you'll be almost as lucky to catch the glide. Obviously, FD/computer enhancement has improved since my comment about "suggestion bars" but even today I've seen modern technology throw a fit.

I believe the original poster was speaking of a time pre-airbus, gps integration etc.

If you refer to the system as a Flight Director, ok. If you call them Command Bars, I'll still have a go.

Beers on me mate.
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Old 4th Feb 2013, 18:56
  #30 (permalink)  
 
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I started airline flying in 1971 on the Boeing 707. We had a very basic flight director (Bendix I think).

More often than not we did not use it - raw data was the norm - we were pretty good at doing it too.
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Old 4th Feb 2013, 20:43
  #31 (permalink)  
 
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Well Firefly,

Look at this thread...

http://www.pprune.org/tech-log/50689...roach-alt.html

It would appear some guys don't know how to execute a G/A in a modern 'electric jet'. What's your take on that?

Disclosure - I'm not a 'bus pilot.

Last edited by Squadronbrat; 4th Feb 2013 at 20:43.
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Old 4th Feb 2013, 22:51
  #32 (permalink)  
 
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Flying a missed approach from a higher altitude than the go around altitude is not difficult but requires at least to be thought about.
The airbus poster may be new at the job and asking here means he is already in the good path-the learning by asking-...
Once this possible maneuver is thought about it is not an issue,however as a surprise,it can cause quite a momentarely spike in CRM
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Old 4th Feb 2013, 23:54
  #33 (permalink)  
 
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Slight digress...

Minor pet hate of mine, Airbus FPV.

Thankfully, our SOP says "Use of FPV is recommended during visual (AP/ATHR off) approach".....but the number of people I've met who seem to think it's a necessity

Whilst (like FDs) they can be useful, get to know the attitude(s) required and learn, don't just blindly follow planting the bird on the horizon to fly level.....
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Old 5th Feb 2013, 00:30
  #34 (permalink)  
 
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FD use

Lots of good posts esp Centaurus' ! I too think that DDM techniques would assist training as would raw data basic take offs and landings in the initial stages.

Most Ab Initio pilots know how to power /pitch /attitude /trim from their initial aircraft, but this is almost lost to technology awe when moving to new jets.

A more 'what bloggs knows' 'what to teach 'how to teach approach would establish understanding that the new shiny automaton flies exactly like their duchess or seminole or whatever before...

I was advocating this approach to training RAAF pilots onto the new tanker KC30 to intro the aircraft in the first few sessions simply as no FMS/automatics at all .. Essentially just take off in ATT REF ...fly a few coordination exercises UAW ( upper air work ) and circuits just to prove it was a PC.9 on steroids. But that is not the way AB train pilots so the course altho modified tends to follow the AB method... Which is designed for a 1500 hour pilot as minimum design entry level by the way, not a 180 hour RAAF cadet... Same applies to the civi training..

Oh by the way , remember it is generally " both flight directors off " in the airbus to ensure speed mode remains engaged and also to ensure not following them does not lead to mode reversions etc... I have seen the results of missing one FD remaining on in sim etc under pressure..

That is my input ..
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Old 5th Feb 2013, 00:40
  #35 (permalink)  
 
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"Looking through the FD"

This discussion inspired me to reflect upon my early experiences with the flight director. I was new to jets, FDs and two crew flying, so to say that my learning curve was steep would be a gross understatement. Just handling the radios, charts, checklists and TOLD cards made me feel terribly behind and of limited value those first couple of flights. When given the opportunity to fly the plane, I felt like I did okay with raw data( or as much as a rookie who doesn't know squat about what to expect can!) but always seemed to be playing catchup with the flight director command bars whenever the FD was engaged. It felt like I chased those FD-109 command bars all over the sky!

After listening to a few helpful hints from my ever so patient and unfailingly supportive captain and struggling perhaps a little less each leg, I learned to anticipate the command bar movements and began to feel as though I could predict their movements well enough so that the bars followed just slightly behind me instead of the other way around. Cappy said whatever you're doing, keep doing it because you found the secret to flying pax without making them sick! Now learn to stay ahead of the speed trends and you'll really be on your way to learning this beast and flying accurately with or without the FD.

And for me that was the key. If you always know what the FD is going to command and when, then you become the master rather than a replacement for the AP servos. I've heard the FD called the electronic flight instructor. Well, maybe at first but I prefer the idea of using the FD to confirm what you already know rather than just following it's cues like a puppy dog trailing it's master. Altitude and course/heading captures are accomplished with smoothness, accuracy and confidence when you're just a bit ahead of the yellow birdie. I've heard this technique referred to as "looking through the FD" too.

Of course the road to becoming a true master of the airplane is much longer and more winding than that, (given enough opportunity) but learning to use the FD to maximum benefit is an important step in the progression. The best pilots I've ever flown with could ALL fly smoothly and accurately no matter what level of automation was being used. I don't think it coincidental that these pilots seemed to be the same ones who took a similar approach to the overall planning and conduct of their flights. Bottom line: If you usually know what's going to happen next you're rarely surprised. Surprise (failure to anticipate) is the mother of most screwups. Seeing through what the FD is doing right now to what it will be doing in the near future is just one example of "staying ahead of the airplane".

Of course the foregoing is just my own perspective on the matter. Yours may be different.
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Old 5th Feb 2013, 02:56
  #36 (permalink)  
 
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I guess we were the lucky generation. We didn't trust the FDs so just flew like a normal pilot using the FD as an aid but not really believing it. We didn't need it at all but amused ourselves by seeing what it was telling us what to do.
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Old 5th Feb 2013, 08:57
  #37 (permalink)  
 
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Westhawk

After listening to a few helpful hints from my ever so patient and unfailingly supportive captain and struggling perhaps a little less each leg, I learned to anticipate the command bar movements and began to feel as though I could predict their movements well enough so that the bars followed just slightly behind me instead of the other way around. Cappy said whatever you're doing, keep doing it because you found the secret to flying pax without making them sick! Now learn to stay ahead of the speed trends and you'll really be on your way to learning this beast and flying accurately with or without the FD.

And for me that was the key. If you always know what the FD is going to command and when, then you become the master rather than a replacement for the AP servos. I've heard the FD called the electronic flight instructor. Well, maybe at first but I prefer the idea of using the FD to confirm what you already know rather than just following it's cues like a puppy dog trailing it's master. Altitude and course/heading captures are accomplished with smoothness, accuracy and confidence when you're just a bit ahead of the yellow birdie. I've heard this technique referred to as "looking through the FD" too.
Excellently said.
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Old 5th Feb 2013, 09:02
  #38 (permalink)  
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The pleasure of a well flown profile descent sans flight director- just ask Anya

On numerous occasions when conducting refresher training in the simulator on 737 pilots who have booked practice sessions because of forth-coming interviews and simulator assessments, I have started with "lets do a few circuits including touch and go's and stiff crosswinds".

Their heads go into the CDU and they start typing a circuit with waypoints, turning points and and final intercepts until a work of art like a beautiful Piccaso type picture appears on the MAP. The booking is usually for one hour because it is very expensive and as their fingers go peck-peck -peck at the keyboard I remind them they have already lost five minutes of flying practice when all that was needed was the HSI, ADI, altimeter and ASI to fly the aeroplane.

But these people are addicted to even using VSI mode on base and final while the support pilot is busy fiddling the buttons and knobs at their direction. OK, the FD's are centred most of the time and some even deselect the heading mode and leaving a solitary horizontal pitch bar for altitude hold. Such is their addiction, like a smoker puffing at his stub, even half a flight director will do. Then the support pilot gets busy again adjusting headings for mid base and final and even hits approach mode to help the PF make a visual turn on to final following the FD needles. Of course the speed control is shot to pieces because the PF is not used to manual throttle control after years of autothrottles.

These are people with umpteen hundreds of hours on 737's mostly with autopilot engaged and the FD needles acting as a crutch to their own basic underconfidence in their ability to fly accurately without an FD. When coaxed into switching off the FD and autothrottle and told to have a go by looking out of the cockpit on the downwind, base and final leg, afterwards the almost universal reply is "Jeez - I enjoyed that - I haven't done circuits since CPL training"

Many years ago, I was lucky enough to have a pleasant year with a German charter operator based in Hamburg and flying the 737-400 and 500. It was there that I crewed with my first female first officer. She was relaxed after crewing with British contract captains as they seemed less strict than their German counterparts.

We were flying back from Spain I think, into Hamburg on a beautiful night and I was mesmerised at the sight of all the city and village lights over that part of Europe. The final track to Hamburg was by coincidence lined up with the duty runway from 100 miles out and Anya as PF (that was her name) had everything set up in the FMC and of course the automatics did a good job.

Top of descent was on the screen, as I thought of all the long straight-in approaches I had done into Pacific island atolls over the past ten years where, in the 737-200, we simply used DME v Height to fly the descent on profile, culminating in a level segment at 3000 ft on final to extend flaps and then straight in still using DME (if it worked ) and height. We had the FD108 FD but most of us never used it. The sense of achievement that it all worked out nicely to over the fence on slope on speed, was such a satisfying feeling.

"Anya", I said, at 100 DME Hamburg straight ahead, "how about you have a go at a profile hand flown no flight director descent, straight in". Anya wasn't sure what I meant, probably because I talked too fast. "You know, DME v Height or three times the height plus 10" I said. Anya looked aghast at my suggestion, as if I was a dirty old man.

"Shhh" whispered Anya, pointing up to, then covering the CAM (cockpit area microphone) with her hand. She seemed scared of Big Brother.

With some cajoling and promising not to tell anyone about this shocking decision not to use LNAV/VNAV , I talked Anya into the descent profile manual flying, manual throttle and FD off. She flew it beautifully all the way to touch-down with just a little help from me with flap/speed control towards the end. A greaser landing topped it all off and we heard the passengers clapping in admiration (or was it relief) at Anya's smooth landing.

As we taxied at Hamburg after the after landing checks, Anya looked over at me and she said "now that was real flying, wasn't it- - and thank you very much - but don't tell anyone, will you" and she pointed to the CVR. "I won't tell a soul, Anya and you flew beautifully" I said back to her.

Well, now I have broken my promise 20 years later and if you read Ppprune, Anya, I know you will understand and forgive me...

Last edited by Centaurus; 5th Feb 2013 at 09:05.
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Old 5th Feb 2013, 15:19
  #39 (permalink)  
 
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Centaurus, nice job getting Anya to accept your coaching. I actually had a First Officer ask me once to turn the automation (AP, AT, FD's) back ON during a visual departure because he was scared. Honest, true story! I was departing KLAS to the west and once above the terrain I clicked all three off. He sincerely asked me to turn it all back on because it was "scaring him".

I turned the Auto Thrust back on, that seems to be where most Airbus neophytes begin to lose it, and continued to fly raw data til level off in the flight levels. I only flew one pairing with that particular FO, so I can't state specifically on his regard, but for the most part I've seen that most AB pilots in that state of mind are actually fairly good hands on pilots; it's just that they were trained to be afraid to fly the AB without the electronic baby sitter.
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Old 5th Feb 2013, 15:22
  #40 (permalink)  
 
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I suspect your real name is Richard Bach and you have a novel hidden inside you bursting to get out.
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