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Subject: B787 Info From A Ua Pilot


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#1 J.O.

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Posted 11 May 2012 - 09:46 AM

Got this from a colleague. Some initial impressions of the 787 from a pilot at United Airlines.


Subject: 787 Features & Differences

I just completed the first pilot training class on the 787 at United Airlines, an airplane which is destined to replace the 767 and live for many years after I retire. Here's what I've learned in 787 training so far. By the way, last night we passed our MV (maneuvers validation) check ride, with emergency after emergency, and the FAA observing. Tonight was our LOE (line-oriented evaluation) [LOFT], again with FAA - this time 2 FAA observers. It's 0200 and I just got back to the hotel and poured a well-earned glass of wine to celebrate. I now have a type rating in the 787. Phew. I'm pretty confident this will be the last one for me.

I've summarized some of the major differences and unique features of the 787 versus more traditional "old school" airplanes like the 777 (not kidding) - from the pilot's viewpoint. Our "Differences" course takes 11 days to gain an FAA type rating, which is a "common" type rating with the 777. The course has been like drinking from a fire hose, but has finally come together. Some of our pilots attended Boeing's 5-day differences course, and deemed it unacceptable. The FAA approved the Boeing 5-day course, but our guys decided it lacked too much information. FAA is observing our checkrides now, and taking our course as well, to certify the training. We're just the guinea pigs, computer nerds would describe the 787 as 17 computer servers packaged in a kevlar frame. The central brains is the Common Core System (CCS). Two Common Computing Resources (CCRs) coordinate the communications of all the computer systems, isolating faults and covering failed systems with working systems. When battery power is first applied to the airplane in the morning, it takes about 50 seconds for the LCCR to boot up. After this, a few displays light up and you can start the APU. If there is a major loss of cockpit displays, this may require a CCR reboot, which would take about a minute.

Here are a few of the major features and differences from the 777. Electrics - Though a smaller plane, the 787 has 4 times the electric generating power of the 777 - 1.4 gigawatts. Generators produce 235VAC for the big power users. Other systems use the traditional 115VAC and 28 VDC. There are 17 scattered Remote Power Distribution Units which power about 900 loads throughout the plane. The big power distribution system is in the aft belly, along with a Power Electronics Cooling System (PECS). This is a liquid cooling system for the large motor power distribution system. There's also an Integrated Cooling System (ICS), which provides refrigerated air for the galley carts and cabin air, and a Miscellaneous Equipment Cooling System for Inflight Entertainment Equipment.

If 3 of the 4 engine generators fail, the APU starts itself. The APU drives two generators, and can be operated up to the airplane's max altitude of 43 000 feet. If you lose all 4 engine generators, the RAT (ram air turbine) drops out (like a windmill), powering essential buses. (It also provides hydraulic power to flight controls if needed). If you lose all 4 engine generators and the two APU generators (a really bad day), you are down to Standby Power. The RAT will drop out and provide power but even if it fails, you still have the autopilot and captain's flight director and instruments, FMC, 2 IRSs, VHF radios, etc. If you're down to batteries only, with no RAT, you'd better get it on the ground, as battery time is limited. Brakes and antiskid are electric - 28V - so you don't lose brakes or antiskid even when you're down to just standby power.

Normal flight controls are hydraulic with a couple exceptions. Engine driven and electric hydraulic pumps operate at 5000 psi (versus normal 3000 psi) to allow for smaller tubing sizes and actuators, thus saving weight.

If you lose all 3 hydraulic systems (another bad day), you still have two spoiler panels on each wing which are electrically powered all the time, as is the stabilizer trim. You can still fly the airplane (no flaps, though). If you're having an even worse day and you lose all hydraulics and all generators, flight control power is still coming from separate Permanent Magnet Generators (PMGs) which produce power even if both engines quit and are wind milling. If the PMGs fail, too, your flight controls will be powered by the 28 V standby bus.

If you lose all 3 pitot/static systems or air data computers, the airplane reverts to angle of attack speed (converts AOA to IAS), and this is displayed on the normal PFDs (primary flight displays) airspeed indicator tapes. GPS altitude is substituted for air data altitude and displayed on the PFD altimeter tapes. Very convenient.

If you lose both Attitude and Heading Reference Units (AHRUs), it reverts to the standby instrument built-in attitude & heading gyro, but displays this on both pilot's PFDs for convenience.

If you lose both Inertial Reference Units, it will substitute GPS position, and nothing is lost.

If someone turns one or both IRSs off in flight (I hate it when they do that), you can realign them as long as one of the GPSs is working! There is no pneumatic system. The only engine bleed is used for that engine’s anti-ice. Wing anti-ice is electric. Each of two air conditioning packs control two CACs, which are electric cabin air compressors. The four CACs share two air inlets on the belly. Each pack controller controls two CACs, but if a pack controller fails, the remaining pack controller takes over control of all 4 CACs.

There are no circuit breakers in the cockpit. To check on them, or if you get a message that one has opened (more likely), you select the CBIC (circuit breaker indication and control) display on one of the MFDs (multi function displays). There you can reset the virtual C/B if it is an "electronic" circuit breaker. You can't reset a popped "thermal" circuit breaker.

If you have an APU fire on the ground or inflight, the fire extinguishing bottle is automatically discharged. If there is a cargo fire, the first two of seven bottles will automatically discharge also. There's a Nitrogen Generation System which provides automatic full-time flammability protection by displacing fuel vapors in the fuel tanks with nitrogen.

Like the 767 and 777, the 787 also has full CPDLC capability (controller-to-pilot datalink communications). In addition, its full FANS capability includes ADS-B in & out. The controller can uplink speed, heading and altitude changes to the airplane. These show up on a second line right under the speed, heading and altitude displays on the mode control panel. If your pilot wants to use them, he can press a XFR button next to each window. The controller can even uplink a conditional clearance, like; After passing point XYZ, climb to FL390. If you accept this, it will do it automatically.

Fuel system - like the 777, the 787 has a fuel dump system which automatically dumps down to your maximum landing weight, if that is what you want. In addition, it has a Fuel Balance switch which automatically balances your L & R main tanks for you. No more opening cross feed valves and turning off fuel pumps in flight. No more forgetting to turn them back on, either.

Flight Controls - An "Autodrag" function operates when the airplane is high on approach and landing flaps have been selected. It extends the ailerons and two most outboard spoilers, while maintaining airspeed, to assist in glide path capture from above, if you are high on the glideslope. The feature removes itself below 500 feet.

Cruise flaps is an automated function when level at cruise. It symmetrically moves the flaps, ailerons, flaperons, and spoilers based on weight, airspeed and altitude to optimize cruise performance by varying the wing camber, thus reducing drag.

Gust suppression - Vertical gust suppression enhances ride quality when in vertical gusts and turbulence. It uses symmetric deflection of flaperons and elevators to smooth the bumps. This should result in fewer whitecaps in passengers' coffee and cocktails. Lateral gust suppression improves the ride when on approach by making yaw commands in response to lateral gusts and turbulence.

Instrument Approaches - The airplane is actually approved for autoland based not only on ILS but on GLS approaches - GPS with Ground based augmentation system, which corrects the GPS signals. GLS minimums are the same as CAT I ILS - 200' and 1/2 mile visibility. Our airline is not yet approved for GLS autolandings, though we will be doing GLS approaches.

Special Cat I & II HUD approaches - These allow lower than normal minimums when the Heads Up Devices are used at certain approved airports (HUDs). The HUDs includes runway centerline guidance which helps you stay on the centerline on takeoff when visibility is greatly reduced. It uses either ILS or GLS for this.

Cabin - Pressurization differential pressure maximum is 9.4 psid, so the cabin altitude is only 6000 feet when at the max cruising altitude of 43,000 feet. There is a cockpit humidifier switch, and cabin air humidification is fully automatic. Cabin windows are larger than other airplanes, and window shading is electronic. The passenger can select 5 levels of shading, from clear to black. The flight attendants can control the cabin lighting temperature, mood lighting, to aid in dealing with changing time zones evening light after dinner, morning light to wake up, etc.

Much of the cockpit seems like it was designed by Apple. The Control Display Units (CDUs) are virtual, so you can move them from one MFD to another. In fact, you can configure the displays in 48 different ways, I think, though we have found a few favorites we will use to keep it simple. To move the cursor from one MFD to another, you can either use a button, or you can "flick" your finger across the track pad (Cursor Control Device) to fling the cursor from one screen to the next - much like an iPad.

I'm going home this morning, and will return for a 777 simulator ride before I go back to work. They want to make sure we've still got the old-fashioned legacy airplane in our brain before we fly the 777 again, even though it shares a "common type rating". We won't get the first 787 until October, and begin operations in November or December. At that time I'll return for at least 4 days refresher training before beginning IOE initial operating experience in the airplane with passengers. What a ride. It may be "fuel efficient", but I'm glad someone else is paying for the gas. John Doe

P.S. If you wish to share this with someone else, be my guest. I think the 787 will be a great plane, but there could be some surprises with this level of innovation. Time will tell. Thanks!

#2 boestar

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Posted 11 May 2012 - 10:22 AM

Excellent post. As he states Time will tell if the technology is up to the imagination of the designers

#3 Moon The Loon

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Posted 11 May 2012 - 11:25 AM

Wow. What a machine. Hopefully worth the extra wait.

#4 Don Hudson

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Posted 11 May 2012 - 01:36 PM

Re, "If you lose all 3 pitot/static systems or air data computers, the airplane reverts to angle of attack speed (converts AOA to IAS), and this is displayed on the normal PFDs (primary flight displays) airspeed indicator tapes. GPS altitude is substituted for air data altitude and displayed on the PFD altimeter tapes. Very convenient."

The following is a comment from a friend, as I'm not an aeronautical engineer:

"Immediate reaction is that they must either be doing something clever of accepting a fairly coarse accuracy when they convert AoA to IAS in the 3 pitot failed case. No problem to calculate IAS for a given weight if you know CL, but the AoA/CL relationship is Mach dependent so you don't know CL unless you make some approximation - maybe inertial ground speed with barometric altitude? (you don't need temperature)."

Don

#5 J.O.

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Posted 11 May 2012 - 03:06 PM

I was wondering about it too Don. Maybe they are using recent "historical" data as a basis to measure the current level of performance. It should be possible to have a memory function that keeps recent speed, weight, temperature and thrust data to use as a baseline to measure current performance when pitot data is missing.

Edited by J.O., 11 May 2012 - 03:07 PM.


#6 xxx

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Posted 11 May 2012 - 07:05 PM

1.4 Gigawatts!!!
1.4 Gigawatts!!!
Where are we gonna find 1.4 Gigawatts??

#7 Rich Pulman

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Posted 11 May 2012 - 11:21 PM

Re, "If you lose all 3 pitot/static systems or air data computers, the airplane reverts to angle of attack speed (converts AOA to IAS), and this is displayed on the normal PFDs (primary flight displays) airspeed indicator tapes. GPS altitude is substituted for air data altitude and displayed on the PFD altimeter tapes. Very convenient."

The following is a comment from a friend, as I'm not an aeronautical engineer:

"Immediate reaction is that they must either be doing something clever of accepting a fairly coarse accuracy when they convert AoA to IAS in the 3 pitot failed case. No problem to calculate IAS for a given weight if you know CL, but the AoA/CL relationship is Mach dependent so you don't know CL unless you make some approximation - maybe inertial ground speed with barometric altitude? (you don't need temperature)."

Don

Airbus has had a similar system for many years. Only difference is that you just need to "fly the green" rather than IAS.

Now, if only Boeing could catch on to the sidestick idea and get rid of that big meal-tipper-over thing they call a yoke. :Grin-Nod: :064:

#8 Kip Powick

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Posted 12 May 2012 - 04:07 AM

.................................

Now, if only Boeing could catch on to the sidestick idea and get rid of that big meal-tipper-over thing they call a yoke. :Grin-Nod: :064:



Rich,

Surely you're aware that Boeing's motto is "NIH" .............. thus you won't see a sidestick in any of their aircraft. :biggrin2:

(NIH = Not Invented Here)

#9 seeker

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Posted 12 May 2012 - 05:03 AM

Kip, that might be part of it but I'd guess that switching from CC to SS would disqualify the common type rating determination which is a big selling feature for any manufacturer.

#10 Boney

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Posted 12 May 2012 - 07:47 AM

quote from RP "....Now, if only Boeing could catch on to the sidestick idea and get rid of that big meal-tipper-over thing they call a yoke. "

.......................

How would the other pilot see what the FP was doing? Hmmmmm

#11 seeker

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Posted 12 May 2012 - 08:37 AM

quote from RP "....Now, if only Boeing could catch on to the sidestick idea and get rid of that big meal-tipper-over thing they call a yoke. "

.......................

How would the other pilot see what the FP was doing? Hmmmmm


Well, when will you ever need that information anyway?

Edited by seeker, 12 May 2012 - 08:56 AM.


#12 Rich Pulman

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Posted 12 May 2012 - 09:59 AM

Rich,

Surely you're aware that Boeing's motto is "NIH" .............. thus you won't see a sidestick in any of their aircraft. :biggrin2:

(NIH = Not Invented Here)

Too bad they don't subscribe to the Steve Jobs ideology of "Good artists copy, great artists steal. We have always been shameless about stealing great ideas.” Just imagine what could be done for aircraft technology if he ran Boeing!

#13 Guest_rozar s'macco_*

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Posted 12 May 2012 - 11:06 AM

How would the other pilot see what the FP was doing? Hmmmmm

Look at the instruments.

/sarcasm
/real talk
/zing

#14 Boney

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Posted 12 May 2012 - 11:15 AM

Being sarcastic....If the NFP on that AF ill-fated flight knew that the FP was holding the joystick full aft during that whole incident, then.....

On airplanes with control columns, one can see the FP control inputs, without having to look at the instruments.

Hmmmmm.

#15 Guest_rozar s'macco_*

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Posted 12 May 2012 - 11:54 AM

Indeed, but since the accident rate of Boeing vs Airbus is identical there is no proof that either is more safe ergo, it is merely down to preference.

I've not flown Boeing but can say that the Airbus side stick makes for the most comfortable flight deck I have worked in, particularly compared to those with a yoke.

#16 Boney

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Posted 12 May 2012 - 12:05 PM

Hmmmm, interesting....

Never flown the SS myself. But, prior to 9/11, I had the pleasure of sitting with some fine chaps on a bus. I will admit that the flight deck was quite uncluttered. Nice.

Until, after that fatefull night, the SS input information is shown on the PFD, then one can say that it may rival the airplanes with the control columns. But you must admit, when a control column is in your gut, it will at least get your attention.

#17 J.O.

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Posted 12 May 2012 - 12:33 PM

There was plenty of information to tell the crew of AF447 what was going on. The question isn't one of the type of controls they had, but why they failed to interpret what was going on. No one who speaks for Boeing has dared to suggest that it couldn't have happened on their aircraft. Birgenair north of Puerto Plata and Turkish at Amsterdam are more than enough evidence that a yoke is no guarantee against a loss of control.

#18 seeker

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Posted 12 May 2012 - 02:02 PM

J.O.

I think we've already hashed this out here on the mighty AEF. You are correct that there is nothing that could prevent this from happening on a Boeing and that the information was available to the AF crew. You can't, however, dismiss the fact that seeing a large control column being pulled back all the way might have been enough of a trigger for the PNF to understand and react to save the day. Yup, he should have figgered it out anyway but he didn't, would he have twigged if he had seen the control column being pulled back? I can't say for sure but personally I think it would have been more likely.
  • Mitch Cronin likes this

#19 Mitch Cronin

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Posted 12 May 2012 - 02:34 PM

You can't, however, dismiss the fact that seeing a large control column being pulled back all the way might have been enough of a trigger for the PNF to understand and react to save the day. Yup, he should have figgered it out anyway but he didn't, would he have twigged if he had seen the control column being pulled back? I can't say for sure but personally I think it would have been more likely.

I absolutely, wholeheartedly agree with that! In fact, I was thinking of saying exactly that, but as usual these days I'm too timid to look myself in the mirror... Anyway...
I've noted a somewhat troubling phenomenon within online discussion of this very question... it appears to me that the sidestick users who will even acknowledge the possibility are, in general, extremely quick to dismiss it. I would have thought a serious safety discussion would negate such prejudicial influence.

How can anyone deny that such a stark visual clue could have been the difference for those folks? Like you, Seeker, I obviously can't say it "would" have been.... But it sure as hell "could" have been. ... I can't help but suspect, that the pnf would have taken the matter to a much better conclusion, had he seen the stick.
Mind you, that was probably a one-in-a-triliion accident, and the odds are it'll never happen like that again... but it could happen tomorrow.

Sticks should be between your legs. You're not flying a computer game. Stay in touch.

#20 Don Hudson

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Posted 12 May 2012 - 04:55 PM

Hi Mitch;

The discussion on SS vs CC has been taken seriously but if I may, I don't think it is itself a serious safety discussion because it hasn't been taken out of the usual modes of thought. It is largely based upon opinions, strongly held but unexamined, at least by the nature of the discussion.

By "modes of thought" I mean examining why people so strongly believe that one system is superior; - everyone argues the case for their favourite system and provides examples and counterexamples which support their particular view but so far I haven't seen convincing arguments for one system over another - arguments which counter the success of both systems. So far, the arguments have not gone, convincingly, beyond personal preference, experience and opinion.

To start with, both systems have their peanut gallery, not just one or the other system. That means that both systems work for many people, not just a majority for one system and a minority for the other.

Secondarily, one accident and the experience of just one crew, (with cockpit discipline, experience and, in my opinion, training and competency issues) is driving the entire present discussion.

I can cite at least two fatal accidents in which the control column was full back in the chest of the PF and the airplane remained stalled until impact - they are the Airborne Express DC8-63 accident, and the Northwest Orient B727 accident (pitot heat off, loss of airspeed info, stalled). One was a test flight and the other a ferry flight.

From the NTSB Report on the Northwest Airlines B727 fatal accident:

Even after the pilots decidod that the aircraft was stalled, the Safety Roard believes that they contfnued to react primrily to the high rate of descent indications and proprioceptive sensations because they continucd to exert a pull force on t!le control column.


From the NTSB Report on the Airborne Express DC8-63 fatal accident:

The failure of the airplane to recover before entering the full stall resulted from the control column inputs the PF was making to maintain pitch attitude. The control column was moved aft by the PF, from 5 degrees aft (at 1808:11, just prior to initiating the recovery) to 20 degrees aft (14 seconds later). An increasingly downward flightpath angle coupled with a relatively constant pitch angle resulted in an increasing angle of attack. The increase in angle of attack, which placed the airplane farther into the stalled condition, may not have been perceived by the flightcrew unless they were closely monitoring the airspeed indicator. In addition, the vertical speed indicator and altimeter should have provided evidence of a developing sink rate and stall.

Thereafter, the airplane began a series of roll reversals, and the airplane remained in an aerodynamic stall condition because the PF held significant back pressure on the control column all the way to impact. Each time the airplane developed a large nose-down pitch rate (combined with reductions in airspeed at 1808:25 and 1809:22), the PF responded with additional back pressure, according to FDR data on control column movement. In contrast, the appropriate pilot response to an uncommanded decrease in pitch attitude (which is, itself, an indication that the airplane is in a stall) would have been forward movement of the control column.31




By the way, both types of flight operations are indicated by the FAA as "higher risk". There is even an FAA SAFO out cautioning airlines to use their flight data analysis programs to closely monitor such flights. The SAFO states, in part:

Approximately 25% of accidents involving turbine powered aircraft during the past decade have occurred during non-revenue flights (e.g.., ferry flights for maintenance purposes or re-positioning flights to pick-up passengers). During this same period, the technology needed for an airline to download and analyze FDR data has become significantly more accessible, either through the airline's acquisition of more affordable FDR data acquisition and analysis technology, or through the use of readily available vendor services.
Discussion: Two common factors found by the National Transportation Safety Board to have been contributory in non-revenue flight accidents are:

(1) the flightcrew's failure to adhere to standard operating procedures (SOPs) and,
(2) the flightcrew's failure to operate the airplane within its performance limitations.


Flight Operational Quality Assurance (FOQA) programs presently in operation by most major U.S. airlines have clearly established the capability of FDR data analysis to objectively identify the occurrence of both such factors.


Many argue that the control column is a significant visual indicator. I do not think so, even if it is in plain view.

As both NTSB Reports indicate, the problem appears not to be the visual confirmation of the position of the control column, (and, I argue, the SS), but recognizing the stall and doing something about it.

Discussion:
As most transport pilots will know... At Mach 0.82, (FL350, say), a typical transport aircraft has an AoA of around 2.5deg, and it will reach the stall AoA at about 4.0 to 5deg AoA. At reduced Mach number the wing tolerates a higher AoA and stalls at around 6 to 8deg AoA. The stall on AF447 occurred at about 7.5deg AoA, but that's because the Mach number had already dropped significantly due loss of speed caused by the instant pitch-up to 10deg by the PF.

The notion of "unloading the wing" was, I understand, a notion taught in the military. Good for them - it, like a HUDS, would likely have saved both these airplanes, (but I don't think AF447 given the absence of cockpit discipline and the rapid loss of situational awareness as a result), but airlines do not teach aerodynamics of high altitude, high-Mach number, swept-wing flight, (although I sense that's changing, given the number of loss-of-control accidents resulting from stalling transport aircraft).

Easier said than done in AF447's case!

If the AoA is in the territory of where the AoA was on AF447, it takes about 20 to 40 seconds and about 15,000ft (at > 18,000fpm down), to unstall the wing. With full forward SS, (or control column), the AoA creeps forward from 35deg at about a degree a second. It only speeds up approach 10deg.

I have data that indicates that a 10deg ND pitch attitude would have been sufficient to unstall AF447, and at altitudes as low as 6000ft although such a scenario requires great care in handling, but FL250 was entirely recoverable. I think this is important information for air crews and an affirmation of the importance of correct application of the stall-recovery procedure. Clearly, such information must be vetted and confirmed by others. But pulling back, either on the CC or the SS, doesn't work.

Airbus and Boeing and, (I believe) Embraer recently cooperated on a presentation dealing with this very problem - handling a stalled transport aircraft. The key is, of course, (and I know you know this), reducing the AoA to below the stall angle. The PPT and the UAS ppts are really interesting presentations, and are at the following links:
Airbus Update on Stall Procedure - Dubai Conference http://fucampagne200...llprocedure.pdf
Airbus - Handling Unreliable Speed http://www.iag-inc.c...iableSpeeds.pdf

Why is the control column perceived and argued by many, as superior to the SS?

By the evidence alone, the notion (and defence of) the control column as an indicator of the other pilot's (the PF's) "thinking" is demonstrably false. We have two examples where the CC was in the PFs stomach and no one did anything, and one example where the SS couldn't be seen and, frankly, we don't know whether the CC would have made a difference given all other factors.

The notion I would like to introduce in favour of the Control Column is the following and as far as I know it hasn't been studied seriously, or discussed seriously yet:

Size matters.

An elevator the size of most of our backyard patios can be moved through its full deflection with about an eight-inch fore-and-aft movement of the Airbus sidestick. In short, the realization or sense of power that one holds over the airplane when using the sidestick, is reduced and perhaps even nil. However, if one grabs "a mitfull" of aileron or elevator by moving the stick a "noticeable" distance, one has a pyschological sense of "a lot", as opposed to "a little" applied authority to the airplane's controls.

I think it is, in manual flight and with limited experience, easy to over-control the Airbus even given the teaching that the sidestick is to be used extremely sparingly and with tiny movements.

I think this is a reasonable discussion point and not an argument for/against one type of control over another.

I liked both, a lot - because I was flying an airplane and not doing something else. But I think the desire for discussion is serious enough to warrant taking it out of personal opinion and looking at it psychologically, ergonomically and from an engineering point of view.

Cheers,

Don

Edited by Don Hudson, 12 May 2012 - 05:07 PM.