Engineering design Vs Pilots perception
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Engineering design Vs Pilots perception
I posted this on another forum and didn't receive a huge number of posts. Maybe it was the wrong forum, or maybe just a crap post but I thought I would try it again on here anyway.
I would be interesed to know what equipments, display, switches, indications, levers etc etc, would you really like to change in the current aircraft you fly, to make them more intuitive to use.
It doesn't matter how large or small the change but obviously your reasons why you think the current implementation should be improved and the solution you determine best.
Two of my favorites are the following:
- Inside-out Vs the Outside-In ADI. Some in depth testing has shown that the "Russian standard" Outside-In view ADi is actually more intuitive to use for recovering from unusual attitudes than the traditional Inside-Out view ADI of the west.
- The story regarding the wing sweep lever for the F-111, in that it was originally designed with the function of lever forward-wings sweep forward, lever back-wings sweep back, perfect one to one mapping, engineers logical solution. However pilots perception is lever forward=go faster, lever back=go slower, along with the other controls in the cockpit that meant something went faster if you pushed it forward and vice versa. So as the pilot wanted to slow down for landing, the wing sweep lever was moved aft and the wings swept back, which was obviously not very nice. The wing sweep lever was subsequently re-designed to stop any potential confusion for the pilots.
Cheers for any info.
I would be interesed to know what equipments, display, switches, indications, levers etc etc, would you really like to change in the current aircraft you fly, to make them more intuitive to use.
It doesn't matter how large or small the change but obviously your reasons why you think the current implementation should be improved and the solution you determine best.
Two of my favorites are the following:
- Inside-out Vs the Outside-In ADI. Some in depth testing has shown that the "Russian standard" Outside-In view ADi is actually more intuitive to use for recovering from unusual attitudes than the traditional Inside-Out view ADI of the west.
- The story regarding the wing sweep lever for the F-111, in that it was originally designed with the function of lever forward-wings sweep forward, lever back-wings sweep back, perfect one to one mapping, engineers logical solution. However pilots perception is lever forward=go faster, lever back=go slower, along with the other controls in the cockpit that meant something went faster if you pushed it forward and vice versa. So as the pilot wanted to slow down for landing, the wing sweep lever was moved aft and the wings swept back, which was obviously not very nice. The wing sweep lever was subsequently re-designed to stop any potential confusion for the pilots.
Cheers for any info.
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Regardless of which controls etc it'd be nice to change to make them more intuitive, you'll have to make sure that you're not going to run foul of the following:
FAR 25.777
FAR Part 25 Sec. 25.777 effective as of 12/01/1978
FAR 25.779
FAR Part 25 Sec. 25.779 effective as of 08/20/1990
FAR 25.781
FAR Part 25 Sec. 25.781 effective as of 08/20/1990
FAR 25.777
FAR Part 25 Sec. 25.777 effective as of 12/01/1978
FAR 25.779
FAR Part 25 Sec. 25.779 effective as of 08/20/1990
FAR 25.781
FAR Part 25 Sec. 25.781 effective as of 08/20/1990
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You do not give details of the research you quote re Russian vs Western attitude displays although I happen to agree with your views IF (and it is a huge if) the pilot has little or no experience of using western displays.
Regardless of which is the better display the task of changing all the western world pilots over to such a different way of thinking would be almost unthinkable. Likely acceptance of such a change would surely depend on the experience level and age of the candidate pilot. Unlearning something SO fundamental would be a huge issue.
Indeed I even wonder how many people used to the western way would even understand your description of the two methods of displaying attitude!
Regardless of which is the better display the task of changing all the western world pilots over to such a different way of thinking would be almost unthinkable. Likely acceptance of such a change would surely depend on the experience level and age of the candidate pilot. Unlearning something SO fundamental would be a huge issue.
Indeed I even wonder how many people used to the western way would even understand your description of the two methods of displaying attitude!
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Unusual Attitudes
In a bizzarre turnabout our UA "trainer" is an L-39 Albatross with a Russian style ADI. So we're practicing UA escape manoeuvers for the Western aircraft we certify in an aircraft equipped with Russian instruments.
Latterly, with everything going glass it's fairly intuitive to follow the big pointy chevron that appears at +30 and -20 degrees of pitch.
Cheers
FT
Latterly, with everything going glass it's fairly intuitive to follow the big pointy chevron that appears at +30 and -20 degrees of pitch.
Cheers
FT
"Unlearning something SO fundamental would be a huge issue."
I dunno, thousands of pilots have converted from Boeing to Airbus!
I'm not telling which side I'm on.
Regards,
BH.
I dunno, thousands of pilots have converted from Boeing to Airbus!
I'm not telling which side I'm on.
Regards,
BH.
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JF - I think one of the sources of information was Roscoe 1968, that detailed results that come down on the side of the Outside-In ADI.
As an honest question, do you think it would really take a huge amount of retraining to fly on an O-I ADI rather than an I-O ADI?
The one aspect that could create a problem in the future for the O-I ADI, is if it was installed in an aircraft with a HUD that obviously presents a display format of I-O. Of course you can then also progress onto the presentation of the roll index as another discussion point for the best format.
On a different note, does the general preference of aircraft reference symbol change when you are manually flying an aircraft, compared to when the flight director is up on the display? Most people that I have spoken to prefer the gull wing reference for manual flying, as it gives a better roll perception and the single cue "chevron" for FD (put the notch in the crotch). We have an aircraft (FAR 23) that will change the PFD aircraft reference symbol based on engagement of the FD or not. This was also done as the SFD has ILS indications in a "gull wing" dual cue format and there would have been potential confusion if the PFD had a dual cue FD.
Thanks
Nigd3
As an honest question, do you think it would really take a huge amount of retraining to fly on an O-I ADI rather than an I-O ADI?
The one aspect that could create a problem in the future for the O-I ADI, is if it was installed in an aircraft with a HUD that obviously presents a display format of I-O. Of course you can then also progress onto the presentation of the roll index as another discussion point for the best format.
On a different note, does the general preference of aircraft reference symbol change when you are manually flying an aircraft, compared to when the flight director is up on the display? Most people that I have spoken to prefer the gull wing reference for manual flying, as it gives a better roll perception and the single cue "chevron" for FD (put the notch in the crotch). We have an aircraft (FAR 23) that will change the PFD aircraft reference symbol based on engagement of the FD or not. This was also done as the SFD has ILS indications in a "gull wing" dual cue format and there would have been potential confusion if the PFD had a dual cue FD.
Thanks
Nigd3
Last edited by Nigd3; 6th Jan 2009 at 07:05.
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Hi Nigd3,
Sounds simple doesnt it; what and how would you change stuff in your cockpit? Don't think it is quite that simple, firstly;
Cockpit needs to be considered as a whole, just chucking in a different AI, no matter how intuitive it is, will only work if it complements all the other aspects of the cockpit. Lighting, FoV, glare, compatibility with data sources, redundancy and loads of other guff.
Secondly;
What are you going to use the ac for? If the role is to remain unchanged this makes things simpler but if the cockpit works as is why change it? If you are upgrading cockpit dispalys for an enhanced or completely new role then this needs to a critical part of your assessment.
Whatever you are looking for good luck but if it is an answer to the skypointer vs earthpointer argument you will never please everybody
Sounds simple doesnt it; what and how would you change stuff in your cockpit? Don't think it is quite that simple, firstly;
Cockpit needs to be considered as a whole, just chucking in a different AI, no matter how intuitive it is, will only work if it complements all the other aspects of the cockpit. Lighting, FoV, glare, compatibility with data sources, redundancy and loads of other guff.
Secondly;
What are you going to use the ac for? If the role is to remain unchanged this makes things simpler but if the cockpit works as is why change it? If you are upgrading cockpit dispalys for an enhanced or completely new role then this needs to a critical part of your assessment.
Whatever you are looking for good luck but if it is an answer to the skypointer vs earthpointer argument you will never please everybody
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Bullethead does make an excellent point; most pilots do not find it very difficult to transition from new technology to old technology. It is, however, very difficult to reach pilot consensus about various design options, as most the design engineers will readily attest. There are differences of opinion between young and old pilots, civil and military pilots, and line pilot versus pilots in management. There are differences of opinion between design authority standards (e.g. French and US) and government regulations. There are often several very good solutions to the same design question. Engineers for the most part would prefer to search for the most elegant solution, but are often required to do so within externally imposed cost, schedule, and regulatory constraints.
O-I ADI rather than an I-O ADI? The market is always the final arbitrator. One design, often regardless of merit, will be selected over the other by the market. The market might be forced to make a selection because a government imposes a design, or because of cost, or because of senior management fiat; but the design or product is rarely selected because it is the most elegant solution.
O-I ADI rather than an I-O ADI? The market is always the final arbitrator. One design, often regardless of merit, will be selected over the other by the market. The market might be forced to make a selection because a government imposes a design, or because of cost, or because of senior management fiat; but the design or product is rarely selected because it is the most elegant solution.
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Hi ianp
Simple, definately not. I've found that total upgrades field the least "gotchas" than the "simple" slotting in of a new display/bit of kit.
We are in the middle of a complete glass cockpit upgrade and the thing that is giving me most grief is the new audio systems output impedance to the headset and the non standard helmet connector. A domino effect of lots of seemingly minor issues are being a real pain in the butt.
Anyway, back on thread, it can be difficult to determine if something is working intuitively as is, until someone makes a catastrophic mistake because they percieved the action they were undertaking under pressure was correct. Kegworth etc. The (un) intuitiveness of a certain control may never be fully highlighted as it doesn't have serious consequences if operated incorrectly and just becomes a pain that aircrew put up with.
The main point of the thread was to see if there were any thoughts from pilots as to why on earth certain items had been designed as they were. If they could also suggest improvements, not necessarily fully investigated/certifieable or even finacially viable, then I would be interested.
Any personal favorites from you?
Simple, definately not. I've found that total upgrades field the least "gotchas" than the "simple" slotting in of a new display/bit of kit.
We are in the middle of a complete glass cockpit upgrade and the thing that is giving me most grief is the new audio systems output impedance to the headset and the non standard helmet connector. A domino effect of lots of seemingly minor issues are being a real pain in the butt.
Anyway, back on thread, it can be difficult to determine if something is working intuitively as is, until someone makes a catastrophic mistake because they percieved the action they were undertaking under pressure was correct. Kegworth etc. The (un) intuitiveness of a certain control may never be fully highlighted as it doesn't have serious consequences if operated incorrectly and just becomes a pain that aircrew put up with.
The main point of the thread was to see if there were any thoughts from pilots as to why on earth certain items had been designed as they were. If they could also suggest improvements, not necessarily fully investigated/certifieable or even finacially viable, then I would be interested.
Any personal favorites from you?
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John - I'd be interested to know why you think the Russian standard is better?
I have experienced a sky pointer and a bank pointer, the sky pointer always points towards the sky, the bank pointer remains stationary on the aircraft as the bank marks on the AI move.
I have also seen the Russian version where the ground appears to be on the top, I see them as three different systems. Initially I hated the sky pointer, as I was used to a bank pointer. That was until I was told the sky pointer always pointed to the sky, so in a bad attitude you can always roll towards it. My level of training was such that changing didn't take too long and I'm quite happy to swap between the two now, but I shudder to think how long it would take to transition to the Russian standard.
I take novices in a mobile simulator in a trailer and in full motion sims. sometimes in the trailer sim people say "oh, the controls work backwards" as they see themselves driving a screen, rather than being in an "aircraft" and driving that. In other words they see themselves moving the graphics. This has never happened in the full motion sim, for obvious reasons. I like the fact the horizon outside and the AI look the same, the Russian stuff looks very weird to me although unfortunately I haven't had the chance to fly in a Russian aircraft.
In an odd attitude, what makes the Russian standard better?
I have experienced a sky pointer and a bank pointer, the sky pointer always points towards the sky, the bank pointer remains stationary on the aircraft as the bank marks on the AI move.
I have also seen the Russian version where the ground appears to be on the top, I see them as three different systems. Initially I hated the sky pointer, as I was used to a bank pointer. That was until I was told the sky pointer always pointed to the sky, so in a bad attitude you can always roll towards it. My level of training was such that changing didn't take too long and I'm quite happy to swap between the two now, but I shudder to think how long it would take to transition to the Russian standard.
I take novices in a mobile simulator in a trailer and in full motion sims. sometimes in the trailer sim people say "oh, the controls work backwards" as they see themselves driving a screen, rather than being in an "aircraft" and driving that. In other words they see themselves moving the graphics. This has never happened in the full motion sim, for obvious reasons. I like the fact the horizon outside and the AI look the same, the Russian stuff looks very weird to me although unfortunately I haven't had the chance to fly in a Russian aircraft.
In an odd attitude, what makes the Russian standard better?
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Nigd3 - it sounds really odd, but I'd like two cup holders and a good secure place to put my sunglasses. The first because in turbulence the cup of stuff often spills and then there is no where to put another drink without resorting to getting cloths etc which there may not be time for. The sunglasses thing is for rapid transition in and out of sunny conditions. If I take my glasses off and have no where to put them they often get in the way or distract me. This is especially true when descending into a cloud layer that may be turbulent or popping into a layer just before landing. I want to be able to take my glasses off, ditch them quickly and safely and have them ready for popping out of the layer later.
I realise I sound like such an airline pilot there, but the military chaps have visors they can slide up and down quickly. I rely on my leg, and the glasses often slip off causing me to fumble right when I don't want to.
I'll have a think about some more serious issues.
Just thought of one - I hate unnecessary abbreviations. They work well for things like VOR, ILS etc, but can be confusing. There is an Airbus message that says IF ABN XXX, a crew at my airline took it to mean AIRBORNE, when in fact it meant ABNORMAL and they did the wrong thing.
We have unnecessary abbreviations littered all around our cockpit when there is space to write the full word/s and the abbreviation isn't getting rid of something huge. Examples are GND for GROUND and L for LEFT. Sometimes reading the EICAS or checklist, the L and R would be much better written as LEFT or RIGHT.
I realise I sound like such an airline pilot there, but the military chaps have visors they can slide up and down quickly. I rely on my leg, and the glasses often slip off causing me to fumble right when I don't want to.
I'll have a think about some more serious issues.
Just thought of one - I hate unnecessary abbreviations. They work well for things like VOR, ILS etc, but can be confusing. There is an Airbus message that says IF ABN XXX, a crew at my airline took it to mean AIRBORNE, when in fact it meant ABNORMAL and they did the wrong thing.
We have unnecessary abbreviations littered all around our cockpit when there is space to write the full word/s and the abbreviation isn't getting rid of something huge. Examples are GND for GROUND and L for LEFT. Sometimes reading the EICAS or checklist, the L and R would be much better written as LEFT or RIGHT.
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JR
Sometimes its the seemingly simple ideas that can be prove to be worthwhile. Apart from keeping things convenient and allowing for time to concentrate on the more serious side of flying, you can maybe appreciate the slightly tongue in cheek scenario below:
AAIB report xyz - After dropping his sunglasses on the cockpit floor, the captain reached down to retrieve them when his left earlobe pressed the main hydraulics switch into the OFF position, that had been invertently left unguarded by the night shift maintenance crew. This caused numerous aural and visual alarms and as the captain raised his head quickly, he knocked a full beverage cup off the centre console with his nose. Fluid went down into the FMS CDU, short circuited the main power supply and caused a burning smell with some smoke.............
With regards abbreviations on aircraft, space and standardistation are the major limiting factors on EICAS etc. "LEFT" and "RIGHT" may be able to be written in full for certain captions, however not for other longer EICAS messages. With regards the "ABN" misinterpretation you quoted, "ABN" has been the standard abbreviation for well over 20 years for "abnormal", with "ABNRM" as an acceptable alternative. You will never get away from abbreviations and all I can suggest is greater familiaristaion with the systems/warning messages on the aircraft. Not much help on that one.
One of the major advantages in how the brain perceives the control-display connection with O-I compared to I-O ADIs is with an O-I (Russian) ADI, the movement of the control column to level the aircraft, is relative to the movement of the aircraft symbol being rotated. For example a left column movement in a right bank rotates the aircraft symbol left (CCW). In an I-O ADI (western), this same left column movement rotates the horizon in a right direction (CW). This is maybe highlighted by some of your students initially saying "oh, the controls work backwards", even though this may not be a prevalent in your full motion sim, it indicates a simple confusion in perception.
Thanks for the feedback.
Sometimes its the seemingly simple ideas that can be prove to be worthwhile. Apart from keeping things convenient and allowing for time to concentrate on the more serious side of flying, you can maybe appreciate the slightly tongue in cheek scenario below:
AAIB report xyz - After dropping his sunglasses on the cockpit floor, the captain reached down to retrieve them when his left earlobe pressed the main hydraulics switch into the OFF position, that had been invertently left unguarded by the night shift maintenance crew. This caused numerous aural and visual alarms and as the captain raised his head quickly, he knocked a full beverage cup off the centre console with his nose. Fluid went down into the FMS CDU, short circuited the main power supply and caused a burning smell with some smoke.............
With regards abbreviations on aircraft, space and standardistation are the major limiting factors on EICAS etc. "LEFT" and "RIGHT" may be able to be written in full for certain captions, however not for other longer EICAS messages. With regards the "ABN" misinterpretation you quoted, "ABN" has been the standard abbreviation for well over 20 years for "abnormal", with "ABNRM" as an acceptable alternative. You will never get away from abbreviations and all I can suggest is greater familiaristaion with the systems/warning messages on the aircraft. Not much help on that one.
One of the major advantages in how the brain perceives the control-display connection with O-I compared to I-O ADIs is with an O-I (Russian) ADI, the movement of the control column to level the aircraft, is relative to the movement of the aircraft symbol being rotated. For example a left column movement in a right bank rotates the aircraft symbol left (CCW). In an I-O ADI (western), this same left column movement rotates the horizon in a right direction (CW). This is maybe highlighted by some of your students initially saying "oh, the controls work backwards", even though this may not be a prevalent in your full motion sim, it indicates a simple confusion in perception.
Thanks for the feedback.
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Hi Nigd,
Have done a bit with glass cockpits but on helicopters. S'pose my main thought would don't be in such a hurry to lose the dials and knobs.
Dials can be much easier to interpret and assimilate at a glance. Engineers seem to love digitising stuff down to numbers and coloured strips.
Knobs, everyone likes to have multifunction soft keys to select crs pointers, baro setting, low height audios etc, sometimes life would be much easier with a good old knob rather than a few minutes stabbing away at bezel keys.
That iss it really without being too specific love those dials (or graphical equivalent) and knobs!
All the best
Ian
Have done a bit with glass cockpits but on helicopters. S'pose my main thought would don't be in such a hurry to lose the dials and knobs.
Dials can be much easier to interpret and assimilate at a glance. Engineers seem to love digitising stuff down to numbers and coloured strips.
Knobs, everyone likes to have multifunction soft keys to select crs pointers, baro setting, low height audios etc, sometimes life would be much easier with a good old knob rather than a few minutes stabbing away at bezel keys.
That iss it really without being too specific love those dials (or graphical equivalent) and knobs!
All the best
Ian
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Nigd3 - it doesn't matter how long ABN has been the abbreviation for "abnormal" the fact is a crew got it wrong on the day. 3 pointer altimeters used to be standard, they are not any more for good reason. I think a number of abbreviations should go the same way. If the EICAS screen isn't big enough to write the full caption, then make the screen bigger! It is much less of a problem nowadays where computer memory is not so very limited as it was. We have 511 mile limits on our range rings because of 512 KB limits on the data point, with modern aircraft this should no longer be an issue.
With Russian and Western AI's, I know what you mean, but what you see on the instrument and what you see outside are opposite. I can't see how that helps, although I am interested to hear other people's views as I am sure they will be interesting and make me re-evaluate my opinion. In my brain, the perception is that the Russian AI's are in the wrong sense - if my training had been different then maybe that wouldn't be true however.
IanP has made me think of something. I love the dial ASI on the 757, with manually moveable bugs and rolling numbers. The rolling numbers are great for seeing a trend, the needle also. Having bugs you can see all the time helps in giving a good gross error check. I used to fly an aircraft with a speed tape and I still find the dial and rolling numbers much better. The speed bugs on the tape used to disappear "up" the tape and only become visible as you went faster. Even though the bug and the number it was set to appeared when you set it, there was no visual cross check until you were barreling along the runway. I believe this was a factor in the Singapore Airlines tailscrape. With our ASI you can see just by looking whether the bugs are in a reasonable place and whether they are set for Flap 5, 15 or 20 takeoffs as the distance between the bottom bug and the next one gets bigger the larger the number of the flaps you use. Its helped me catch errors before.
Appearing numbers are next to useless (tell Honda!), rolling numbers are great. No trend in the first, plenty of trend in the second.
BTW my "students" (really the public) in the sim are looking at the outside screen, not the AI when they say it is "backwards".
With Russian and Western AI's, I know what you mean, but what you see on the instrument and what you see outside are opposite. I can't see how that helps, although I am interested to hear other people's views as I am sure they will be interesting and make me re-evaluate my opinion. In my brain, the perception is that the Russian AI's are in the wrong sense - if my training had been different then maybe that wouldn't be true however.
IanP has made me think of something. I love the dial ASI on the 757, with manually moveable bugs and rolling numbers. The rolling numbers are great for seeing a trend, the needle also. Having bugs you can see all the time helps in giving a good gross error check. I used to fly an aircraft with a speed tape and I still find the dial and rolling numbers much better. The speed bugs on the tape used to disappear "up" the tape and only become visible as you went faster. Even though the bug and the number it was set to appeared when you set it, there was no visual cross check until you were barreling along the runway. I believe this was a factor in the Singapore Airlines tailscrape. With our ASI you can see just by looking whether the bugs are in a reasonable place and whether they are set for Flap 5, 15 or 20 takeoffs as the distance between the bottom bug and the next one gets bigger the larger the number of the flaps you use. Its helped me catch errors before.
Appearing numbers are next to useless (tell Honda!), rolling numbers are great. No trend in the first, plenty of trend in the second.
BTW my "students" (really the public) in the sim are looking at the outside screen, not the AI when they say it is "backwards".
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Jetstream Rider,
It may interest you to know that besides his long-time input for Harrier & other cockpit displays, and of course his experience in the MIG 29, John Farley was going to ( I rather expect, did ) design the cockpit layout of Richard Noble's Farnborough Air Taxi project, which fell due to finance.
An ex-Flight Test chum had a job for a while helping design the Typhoon cockpit; it turned out much could be learned from computer games, which have to be simple & 3D for teenagers to fly spaceships !
It may interest you to know that besides his long-time input for Harrier & other cockpit displays, and of course his experience in the MIG 29, John Farley was going to ( I rather expect, did ) design the cockpit layout of Richard Noble's Farnborough Air Taxi project, which fell due to finance.
An ex-Flight Test chum had a job for a while helping design the Typhoon cockpit; it turned out much could be learned from computer games, which have to be simple & 3D for teenagers to fly spaceships !
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You mention you have seen a Russian version where the ground appears to be on the top. That is a new one on me – but perhaps we are not talking about the same thing.
The Russian A/I display that I refer to has an aeroplane symbol that is free to roll with respect to the cockpit coaming and is viewed against a pitch drum that rotates about a horizontal axis fixed in the plane of the instrument panel. This makes for a very simple and reliable instrument which has no toppling limits like our A/Hs.
Back in 1990 I talked at length with the Mikoyan tps including their CTP Valery Menitsky and they were very open saying they had thoroughly evaluated both modes of display but still favoured theirs. Afterwards I attended the SETP symposium in LA in 1990 to help Valery give a paper there and afterwards there was an open discussion with the floor. During this I explained that before I did a MiG-29 evaluation that included a lot of manoeuvring in cloud (the base was 300ft) I had great reservations about unlearning my instinctive reactions and what model I should use in my head to ensure I did not get confused.
The model came from a nice soak in a bath the night before the flight where I reasoned that the view of this rolling aircraft against the pitch ladder was just like looking at my leader when I was flying line astern on him as he manoeuvred against the sky (something fighter pilots spend a lot of time doing) I reasoned that all I had to do was ‘remotely control my leader’ and make HIM do what I wanted MY aircraft to do. Bingo it worked like a charm and seemed very natural. Given that I was 57 at the time and had not flown a fast jet for several years the fact that I found it so natural must say a lot for the concept.
Of course (as an aside) this is how a lot of modern flight sim guys fly ‘their aircraft’ by viewing it from behind.
JF
You mention you have seen a Russian version where the ground appears to be on the top. That is a new one on me – but perhaps we are not talking about the same thing.
The Russian A/I display that I refer to has an aeroplane symbol that is free to roll with respect to the cockpit coaming and is viewed against a pitch drum that rotates about a horizontal axis fixed in the plane of the instrument panel. This makes for a very simple and reliable instrument which has no toppling limits like our A/Hs.
Back in 1990 I talked at length with the Mikoyan tps including their CTP Valery Menitsky and they were very open saying they had thoroughly evaluated both modes of display but still favoured theirs. Afterwards I attended the SETP symposium in LA in 1990 to help Valery give a paper there and afterwards there was an open discussion with the floor. During this I explained that before I did a MiG-29 evaluation that included a lot of manoeuvring in cloud (the base was 300ft) I had great reservations about unlearning my instinctive reactions and what model I should use in my head to ensure I did not get confused.
The model came from a nice soak in a bath the night before the flight where I reasoned that the view of this rolling aircraft against the pitch ladder was just like looking at my leader when I was flying line astern on him as he manoeuvred against the sky (something fighter pilots spend a lot of time doing) I reasoned that all I had to do was ‘remotely control my leader’ and make HIM do what I wanted MY aircraft to do. Bingo it worked like a charm and seemed very natural. Given that I was 57 at the time and had not flown a fast jet for several years the fact that I found it so natural must say a lot for the concept.
Of course (as an aside) this is how a lot of modern flight sim guys fly ‘their aircraft’ by viewing it from behind.
JF
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Displays
That remark by John Farley about 'simulator guys' sounds very correct; at Tangmere museum, we have 3 'simulators' ( of course they're really just adapted games with decent throttle & stick controls, but with specially written software to involve Tangmere or people / aircraft which flew from there ).
The simulators give the facility to view the aircraft 'from the outside' at various angles - I have noticed people who are not trained pilots find this particularly useful, wheras going by the instruments would leave a big smoking hole in cyberspace...
Must be a lesson there somewhere about intuitive displays.
For those who fancy their chances, one can try to fly a Hunter through Tower Bridge, as was done in reality by a pilot who is a local.
I managed it at a relatively sedate pace, but when I tried to be a smartarse and go under the lower span ( it can be done ) my results were not pretty...
As soon as we are up & running again in March, I'll have another go.
BTW we have a large library available to the public, over 5,000 books.
I know, as I'm one of those cataloguing them !
The simulators give the facility to view the aircraft 'from the outside' at various angles - I have noticed people who are not trained pilots find this particularly useful, wheras going by the instruments would leave a big smoking hole in cyberspace...
Must be a lesson there somewhere about intuitive displays.
For those who fancy their chances, one can try to fly a Hunter through Tower Bridge, as was done in reality by a pilot who is a local.
I managed it at a relatively sedate pace, but when I tried to be a smartarse and go under the lower span ( it can be done ) my results were not pretty...
As soon as we are up & running again in March, I'll have another go.
BTW we have a large library available to the public, over 5,000 books.
I know, as I'm one of those cataloguing them !
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Double Zero - I have in fact met Mr Farley at a lecture he gave some 16 years ago. We had a chat afterwards and it remains one of the most informative and well explained lectures on aviation I have ever been to. I don't expect him to remember a little boy at North Weald asking him about Ski jumps for the Harrier, but I remember it well!
The reason I ask here is because I know that with people like John and the others on this forum, I will get a decent well explained response that will make me think, rather than uninformed speculation.
John - Thanks for explaining that, I've not seen the instrument which you describe. The one I saw was decidedly odd. I thought it had toppled, but apparently not. I'll see if I can find one to look at.
Kind regards.
The reason I ask here is because I know that with people like John and the others on this forum, I will get a decent well explained response that will make me think, rather than uninformed speculation.
John - Thanks for explaining that, I've not seen the instrument which you describe. The one I saw was decidedly odd. I thought it had toppled, but apparently not. I'll see if I can find one to look at.
Kind regards.
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Having tried both sky and ground pointer AI's in numerous aircraft and sims, my observation is that the sky pointer had more initial wrong moves to change bank angle than the ground pointer.
Other areas where controls / displays could be set up two different ways were in helicopter landing light switches and gimbal imaging system (FLIR, etc).
For the helicopter landing lights the options are moving the switch forward moves the light up or it moves it down. After lots of discussions, the test was to see which orientation led to the most initial incorrect movements - and the orientation with the 'move the switch up to move the light up' won hands down. Ditto for the FLIR- did lots of demos of FLIR to first time users, and engineers loved the move the switch up to move the line of sight up. Pilots hated it.
In both cases if the control had been a joystick type of control instead of a fore-aft switch, it might have been more obvious to the designers to make the control work more like an aircraft flight control.
Of course, in the US Army's OH-58D with it's mast mounted sight, the problem of which way should the sight be controlled was solved by putting in a switch to allow the operator to choose...
Other areas where controls / displays could be set up two different ways were in helicopter landing light switches and gimbal imaging system (FLIR, etc).
For the helicopter landing lights the options are moving the switch forward moves the light up or it moves it down. After lots of discussions, the test was to see which orientation led to the most initial incorrect movements - and the orientation with the 'move the switch up to move the light up' won hands down. Ditto for the FLIR- did lots of demos of FLIR to first time users, and engineers loved the move the switch up to move the line of sight up. Pilots hated it.
In both cases if the control had been a joystick type of control instead of a fore-aft switch, it might have been more obvious to the designers to make the control work more like an aircraft flight control.
Of course, in the US Army's OH-58D with it's mast mounted sight, the problem of which way should the sight be controlled was solved by putting in a switch to allow the operator to choose...
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I'm not a pilot, but have done a lot of flying as a 'free autopilot' in light aircraft when the CPL or ferrying Test Pilot was bored or giving me the chance, + a lot of 'simulator' time in varying degrees of realism, everything from multi-million £ jobs to PC games; my instinct with the light / FLIR would certainly be push forward, go down...
Incidentally, while not re. displays, this is a similar snag; I knew a very experienced Harrier Test Pilot ( not J.F. ) who for some reason had to test microlights of the 'hang glider with a pusher engine' variety; he remarked it went against the grain to push the wing control bar forward to go up !
Incidentally, while not re. displays, this is a similar snag; I knew a very experienced Harrier Test Pilot ( not J.F. ) who for some reason had to test microlights of the 'hang glider with a pusher engine' variety; he remarked it went against the grain to push the wing control bar forward to go up !