Cocpit design requirements [Archive]

Pilot DAR

12th Nov 2010, 02:52

Knowing the subject aircraft type, and discipline helps.

In a tilt rotor, I would expect that at certain critical phases of flight, I would want the aircraft systems to take care of themselves, and only notify me when my action will be required to intervene with a decision the systems cannot make.

I do not want distractions at critical phases of flight. I most dislike having to divide my attention both inside and outside at the instant of lift off, to optimize engine power, when it should be able to optimize itself. Example of bad: AS355 helicopter, where just as you reach maximum power as you pick up, you have to have to look at the power indicator to match the engine powers to each other with a switch on the collective. Good: EC120, whose power display for it's single engine, graphically displays the percentage of the most critical engine limitation only.

Thus, I would like a tactile limitation marker, it would work as follows: As you apply power (be it the raising of the collective on a helicopter, or moving the power lever(s) on an airplane), a electric motor driven "bumper" which the pilot would feel at the point where the "system" regonizes the first limitation for that engine, would be motored to the limitation point. If the pilot needs more power, he/she can still pull/push past this tactile bumper and get it, but now you know that you're pulling too much, and it's gonna cost a lot! If there is a "5 minute" rating, it could start to time it at this moment. Maybe the control would have a subtle shaker to tell the pilot they are within a timed limitation. The display should show the relative power being demanded, and the position of the tactile stop at that moment. Interestingly, the Schweizer 300 helicopter has a very basic form of this, which is simply two fixed position rivets on the collective friction slide, you'll feel them if you pull through it to overboost the power, but you still can if you really need to.

Surley a sharp avionics guy can design a system where the sytem computer knows what the engine(s) are doing, how much additional power is available, and electrically drive a tactile stop to that point. The pilot will feel it, and can pull through, but has a sense of remaining within limitations, without looking inside at all. The DA 42 has somting like this for pitch limitation, though you cannot pull through it - it's just there!

The system can further assist the pilot by repositioning this tactile stop, in the case of an engine or other failure, which effects total power. In the case of exceeding a "5 minute" limitation, the tactile stop might be motoring back down below the presently set power. As it passes down, it will bump the control down, and the pilot would feel it. Again, maybe a small shaker. This would be accompanied by a display on the critcal power indication display, so the pilot can look at where things are. There are systems with tones for this, but we already have too many tones in the cockpit.

Presuming the tilt rotor has a height velocity curve (I'd sure be courious to see what it looks like!) I would like a computed indication of my phase of flight relative to the HV curve, for the prevailing contitions. Sort of like an angle of attack indicator for a fixed wing aircraft. Green is good, amber use caution, red - do you really want to be doing this? Again, no tones, just a very simple display, in the field of outside view. This display might also offer HIGE/HOGE information, when the airspeed drops below a certain value. (You can/cannot hover out of ground affect right now).

A tilt rotor has some very uncommon failure modes, and related pilot actions. Do you glide or autorotate? If you're gliding, can you turn it into an autorotation at the required moment, or do you smash off the rotors as you land horizontally. The avionics should be propmting these actions, and offering the tolerances available for a successful outcome.

Presuming that the display is offering some kind of terrain awareness, this must be easily disabled when desired. When in operation, the "system" should be constantly displaying as a moving, variable dimension cone, where the aircraft could be in the next minute with the power available (out climbing or out turning terrain or other hazards). The G 1000 does this in a simple way, in the mapping view - I like it!

If you can figure out how to build it, let me know, I'd love to fly it!

Genghis the Engineer

12th Nov 2010, 06:23

Genghis:

You're absolutely right, and there are some HUGE risks on this project, but fortunately I'm an avionics chap not structures.

We've taken a long hard look at the Osprey problems and are aiming to incorporate their lessons in our design - Bell have been struggling for years to get certification despite pausing their developement to learn the Osprey lessons.

Thanks for the other inputs - exactly what I was hoping for.

Ah, but you're on the Cranfield MSc, which is probably the best regarded product of its type globally. It didn't get that reputation by making life easy for the students!

Check your PMs - I don't think that there is any substantial tiltrotor experience on here (although I'd certainly pay much attention to Pilot-DAR's comments above, he is a very experienced flight tester of smaller aircraft), but I've pointed you at where the real expert is.

Also, as an appropriate student, you are eligible for student membership of SFTE at about US$15/year - join, then see what's available on their papers database. (Society of Flight Test Engineers (http://www.sfte.org))

G

Milt

12th Nov 2010, 11:41

Don't overlook the need for the "Standard Man" to be able to operate everything and I'm still looking for the standard woman.

Genghis the Engineer

12th Nov 2010, 14:05

I haven't looked them up for a while, but NASA used to publish some really nice anthropometric tables showing 5th, 50th and 95th percentile caucasian male and oriental female proportions.

I'm not sure where they exist any more, but doing a quick search this (http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20090026488_2009026743.pdf) should provide you with a reasonable start point.

G

peeush

13th Nov 2010, 05:30

As far is avionics interface in cockpit goes, I would suggest that an intelligent mix of tones and voice warnings must be considered while deliberating on each 'Phase' of flight likely to be undertaken- i.e hover, forward flight (airplane mode), rearward flight (possible ?), hover turns, glide/autorotation and of course vertical pick up and sit downs. While keeping the certification requirements in focus, the pilot-machine interface will finally depend on the missions envisaged and the cockpit (crew) load while undertaking these acts. Thus, consider each phase of flight separately for all the missions listed out by the user agency. Prioritise the parameters through a table and then select the best feasible option for pilot interface while allowing him to focus his eyes at his priority without jeopardizing flight safety/ life of the expensive components. As an engineer you can only optimise the technology for your machine however, making use of all the sensory organs available with the crew (ALL of them) will provide edge over the contemporary. Please remember that even the flight parameters need to prioritised for every phase of flight and using HUD/HMD may not be bad idea. So the voice warnings, tones, tactile cues must be employed together while providing our pilot with only the information necessary at THAT MOMENT.

Hope it helps !!!!!

glum

13th Nov 2010, 17:01

Wow, some GREAT posts gents, thank you.

Pilot DAR, you're caused some very creative juices to flow!

Since our aim is to simplify the job of flying as much as possible on such an odd beast, our focus will be on automating many things such as the transition from hover to forward flight and back again (a lot of algorithm writing ahead!)

One of the worst problems for the V22 as I understand it is the susceptability to vortex ring instability caused by descending too quickly - exactly the kind of thing which needs warnings / autonomous control.

Having done some reseach into the training being undertaken with pilots whereby the displays will 'fog out' all non essential information should an emergency event occur, I believe this is definitely a way forward in display design. Again, it will need careful thought and prioritising of dangers (is the engine fire or terrain going to get you first?)

One of the idea's we've gone for is to remove the rudder pedals, since it is a fly by wire aircraft and the 'monkey downstairs' can take care of co-ordinating turns. Any yaw required during hover mode can be actioned with a twisting motion on the joystick. Is this a step too far regarding conversion from other types perhaps?

ICT_SLB

14th Nov 2010, 04:46

Glum,
The conversion task for fixed to tilt rotor may be overstated. I used to work with the project pilot for the Canadair CL-84 "Dynavert" tilt wing. He said an competent pilot could convert in a couple of hours. This older program might be a good source overall as well. Similarly I think you'll find that, once you're in a Vortex Ring, it's often too late - the best action is avoidance not any automatic takeover although I'm not sure if there are defined parameters like there are for Ground Proximity or Windshear.

As one who has worked his way through an EICAS development, the one question you must apply to any system alert is "What is the pilot's next action?" It's surprising how many Warnings come down to just a Status message if there's nothing he needs to (or can) do when the failure occurs. There was a very well reasoned CAA publication on alerting & flight phases but I'm afraid I don't have the reference here at home.

Pilot DAR

14th Nov 2010, 13:59

It's surprising how many Warnings come down to just a Status message if there's nothing he needs to (or can) do when the failure occurs.

I sure agree with that! So many times I've wanted to ask an avionics designer, at the very moment of a tone or other warning/annuciation/light; "Yeah, so what is it you actually want me to do at this moment?". We can be overloaded by information, and a person's total capacity can be quite variable depending upon what's going on at the moment. The avionics designer sits in a quite room, considering all the things he wants the system to tell the pilot at any given moment, and how. He/she may not adequately consider that additional avionics which will be added to the aircraft later, which will have all of their own tones and alerts too, along with the busy environment the pilot is in when he's actually flying. Those few tones and lights going off, coupled with the comm radio, poor weather on the horizon, rough air, the pilot thinking about explaining to the boss that he might have picked off a tree branch with a rotor balde and damaged it, and having to get back in time for his kid's soccor.

Recall the basics: "aviate - navigate - communicate". Those are the priorities. There have been many times I have tuned out "communicate", and even "navigate", to assure that aviate was properly accomplished. I can recall during long line training at a controlled airport, telling the tower I would remain in the area assigned, and turn the radio down, so I could concentrate. He agreed, and I concentrated.

It is imprtant that as much as possible, the pilot be able to cancel tones and alerts, so "aviate" can predominate. And, as said, if there is no action the pilot can take anyway, tell him later!

While considering all of this, also consider what the pilot will have on his/her side, when the annuciation system itself fails. If the pilot is expecting a warning from the system, should a certain parameter be exceeded, but the warning sytem itself has failed, how does the pilot know that he must now monitor that function directly?

I'm glad I'm not an avionics engineer, so I can sit here and be critical, without having to have to figure out the solutions!

John Farley

15th Nov 2010, 08:33

I'm currently studying an MSc in avionic system design at Cranfield, with a focus on cockpit / flight deck design.

Since our aim is to simplify the job of flying as much as possible on such an odd beast, our focus will be on automating many things such as the transition from hover to forward flight and back again (a lot of algorithm writing ahead!)

Which is you are trying to do? Sorting out a cockpit and designing flight control systems are two VERY different objectives.

I don’t know who has told you that controlling the transition on a vectored thrust aircraft is difficult, but I can assure you it is not. In visual conditions you do not even need to refer to an instrument in either the accel or decel case. In cloud you need to keep your wings level and your pitch attitude roughly flat with reference to the attitude display to prevent any risk of the wing stalling angle being reached. (This attitude control is what you do by simple visual references when these are available). That just leaves height control.

For HEIGHT control the accel and decel need two different techniques:

Accel - from a VTO leave the power set as needed for a gentle climb or from a steady hover increase the power to give a slight positive climb. Then leave the power as set and push the nozzle lever forward (or use the nacelle pod angle trim switch to reduce the pod angle) until you reach full travel on the control by which time you HAVE to be flying on your wings.

All that is left to discuss is the RATE at which you rotate the thrust vector. That is SO simple it hardly needs describing – move the nozzle lever too fast and you will sink, move it too slowly and you climb unnecessarily high. So during the accel your nozzle lever rate of movement is your height control. Visually this is obviously a piece of cake while in cloud it behoves you to keep an eye on the VSI.

http://img.photobucket.com/albums/v145/johnfarley/Transition_diagram.jpg

This diagram shows that in the hover if you rotate the thrust vector 15 deg aft of the hover angle you IMMEDIATELY generate a 0.26 g longit accel but thanks to the trig relationship you only loose 0.03% of your vertical component – hence the desirability of the slight initial drift upwards from the VTO or hover. Pure magic and on first acquaintance it appears to mean you get something (0.26 g accel) for nothing.

0.26 g is of course quite a brisk accel and soon leads to airspeed and wing lift. Once this builds a climb will result unless you continue to rotate the vector. This is all a lot easier to do than write about. Many Harrier pilots in two nations were converted to doing this with no simulators and no two-seaters without trouble.

Decel. Transition – in normal wingborne flight go downwind at normal circuit speeds (say 1.3 to 1.5 stall speed – it is not at all critical) deal with gear and flaps as usual and turn base. Roll out a mile or so before you want to hover and SELECT the thrust vector to the hover position. (This is a true ‘selection’ not a flying control type of action).

Once you do that you have chopped off all ‘thrust’ and the aircraft will slow down quickly thanks to the drag. NOW IN YOUR HEAD HOVER the aircraft and ignore the speed which is still present. IE control height with power and maintain the hover attitude. As speed and wing lift washes off increase power to maintain the approach path you require until you find yourself in the hover.

With practice it is easy to select a particular hover point by small adjustments to the pitch attitude or thrust vector angle, but that is exercise two not one.

JF

glum

15th Nov 2010, 21:48

John,

Very interesting insight there. I am left wondering if our Tiltrotor would be quite as capable, since I suspect the power-to-weight isn't quite on a par with a Harrier.

We have two RTM322-01/9A Making somewhere between 1566kw (max continuous) and 2204kW (30 seconds OEI). Bolted to those are a pair of rotors approx 8m in diameter (final sizing still under design).

Not quite a Pegasus! :(

Still, I have raised your points with some of the design guys more focussed on the control systems, and it's opened their eyes - we were expecting this to be a very tricky phase and therefor had resigned ourselves to completely autonomous control.

To those who've raised the tone ( ;) ) issues, and that of annoying warning systems that's great input. Sounds like a common dissatisfaction there.

We have had it pointed out to us that engineers have a tendancy to design arcraft for engineers, but it isn't engineers who fly aircraft!:=

John Farley

16th Nov 2010, 18:54

Ta glum

The Harrier T/W will not be very different to your machine (or any other that can hover) - else it can't hover! While a light Harrier could be 1.5:1 these days it will normally be operating around 1.05 to 1.15 because of the need to carry stores or fuel or both.

Anyhow as long as you realise the essential simplicity of vectored thrust (whatever is providing the thrust) then that was all I was after.

I suspect the aerodynamic interaction of the rotor downwash/slipstream and the wing and tail will produce a few trim changes that will need looking at - just as the Harrier engine efflux has a powerful effect on the tailplane local AoA during transition hence stick position to trim as the speed varies.

Anyhow good luck!

JF

ICT_SLB

17th Nov 2010, 03:34

"We have had it pointed out to us that engineers have a tendency to design aircraft for engineers, but it isn't engineers who fly aircraft!"

Which is why most aircraft design teams include representatives from the Flight Test group - both pilots & system engineers - who operate, test & maintain the current designs. In our organization, they're part of all design & test reviews including "Safety of Flight". Current aircraft are often just too complex with layers of "gotchas" - you can fix one problem only to reveal another one (or two or three) that was masked by the first.

Genghis the Engineer

17th Nov 2010, 08:41

Adding to that, and at risk of stating the blindingly obvious, given the students here are at Cranfield - this is a large airfield, as as well as a university. The place is full of pilots, so getting a pilot opinion shouldn't be difficult.

Slightly more difficult will be finding a pilot whose opiinions are worth listening to, and can articulate them well enough to be useful to you. However, they'll exist at Cranfield somewhere, and it's a worthwhile challenge!

G

sycamore

17th Nov 2010, 12:51

Glum, one man to speak to with `authority` would be the CTP Roger `Dodge` Bailey.
Earlier it was mentioned that you were doing away with the rudder pedals- and using the stick ,by twistingfor yaw control. I think you are going a step too far by bringing to a `hybrid helicopter/aeroplane ` a novel control system. This may be because you have been playing too much on MS Flight sims,and have little ,or limited actual flying experience of how aircraft are controlled,especially helicopters.
As a starter,you need to steer the aircraft on the ground,you need brakes,; you need seriously to look at the `ergonomics` of various manoeuvres that are used in the hover mode such as moving the `cyclic` control,which may have several switches/buttons on it,and then consider the relationship of those contols whilst you now twist the stick; Ones` wrist has only a limited range of movement in certain planes,and whilst using the fingers on the stick grip,you would find it increasing difficult to operate.
The rudder/yaw pedals can be fly-by wire,but they can also serve to give the pilot feedback,can `tremble` if nearing a control authority limit,or a yaw rate limit or a sideslip limit ,which I consider you would not be able to do by using a `twist-stick`. Remember, that the lower speed end of the aircrafts` envelope is where it is operating in a `seat-of -the pants` environment,where one uses one`s senses more than in conventional flight,and control must be instinctive. Remember, pilots who convert to these `hybrids` have/will come from both helicopters and fixed wing,where the basic control functions /responses are largely the same,so putting in another new-concept will make it a higher workload. It is one thing to sit at a desk and play with a computer stick- quite another to strap your backside into a real aircraft ...You may try a PM to `Ospreypilot` who may have some thoughts on the subject,or he may be busy in a hot,sandy place...

Vc10Tail

17th Nov 2010, 16:19

Cockpit Ergonomics/crew anthropometrics,System design based on aircraft economics as the base line,aerodynamic and structural inputs from the proposed aircraft design,seating and emergency escape arrangement,electrical and electronic compartment location,panel optimum viewing angles,windshield and overhead angle,display options, control levers position and reach options,Instrumentation displays to comply with international design standards,
standard/.efis instrumentation mix, pickle /rotary/push button switching,control colum design (rams horn,u wheel,or joy stick design, fly by wire or conventional control systems,cockpit door security and control system,communication systems,glareshield design and interface with flight mode annunciation,emergency equipment and systems,HUD systems,Throttle quadrant design...e.g boeing versus airbus format, etc..seat upholstry design depending on mission requirements,sealed windscreen versus window type design, oxygen and ventilation systems,rudder pedal and nose tiller design and whether singular or dual tillers.

At some point you have to consider inputs from structural engineers, telemetry and instrumentation engineers, aerodynamiscist, ergonomists, cost engineers etc...

just my humble take on the matter

glum

17th Nov 2010, 22:59

Sycamore,

I speak only as an avionics tech of 23 years - never been a pilot though have spent many hours staring out the window at 35,000 whilst waiting for the captain to play his scrabble hand!

Good insight to the rudder pedal issue, and yes I was thinking along the lines of future generations of MS Flight Sim pilots, who would perhaps find it natural to have the yaw control on a joystick, rather than those converting from a position of experience. We are students and have the luxury of dreaming a little!

The role of a pilot is being relegated to systems manager with each passing decade, and I fear seat-of-the-pants flying is becoming increasingly rare on civil aircraft. As the computers take over, the need for 'feel' is reduced since all the pilot needs to do is tell the aircraft which way to fly, and the aircraft obeys - taking account of the flight envelope, weather conditions, traffic, terrain, thrust available etc.

Ultimately there may not even be a joystick...

ICT_SLB

18th Nov 2010, 03:11

Glum,
"Ultimately there may not even be a joystick... "

I've got in trouble before now for pointing out that most current transports can be flown without manual control input from around 500 feet after takeoff (Minimum Engage Height) to touchdown.

Please post a link to your team's project when you've finished it - as Genghis has said, it will be interesting - and refreshing - to see what could be done especially when you don't have to consider the impact of legacy systems or traditions.

stilton

19th Nov 2010, 07:44

John,

As usual your Harrier insights are fascinating. I think your inputs were also instrumental in the design of the F35B.

Having said that, what do you think of the progress of that program and the technology as it exists in that Aircraft today.

I realise I digress from the thread, but it appears the magnificent, rugged and in comparison, mechanically simple and reliable Harrier will be 'going away' soon to be replaced by what has become in my humble opinion an extremely expensive, maintenance intensive 'gold plated' Joint Strike Fighter.

Is all that, complexity, weight and expense 'worth it' in your opinion ?

Piltdown Man

19th Nov 2010, 08:28

Personally I'd like proper light controls and light shields so that the other chap doesn't get blinded by their colleague when they need light to perform something. I'd like window wipers that work and controls that have appropriate power/feel ratios. I'd like an FMS that has a consistent control and simple 'buttonology.' I'd like footrests that don't dig in just below your kneecaps when you have the proper seating position. I'd also like an autopilot interface that makes it easy for you to fly the aircraft rather than the other way round. I'd also like indicator lights above the mode selector buttons on the glareshield.

I fly an Embraer "E Jet" and this aircraft, whilst very capable, is a complete and utter pain to fly if you compare it with a Fokker (70/100). In the list above, the only thing Embraer have done a reasonable job on is the windshield wipers. But if I had to list it's good points (from a pilot's perspective) I'd include the FADEC engine controls, steering, brakes and external visibility (except with with Flaps 5) and the overhead panel which contains no useful information whatsoever, so can be completely ignored. But I don't think these make up for the diabolical rubbish supplied by Honeywell which we have to do battle with each day.

PM

NutLoose

19th Nov 2010, 10:02

JAR-25 !!!FOR STUDY PURPOSES ONLY!!! (http://www.fzt.haw-hamburg.de/pers/Scholz/vorschriften/JAR-25.html)

Genghis the Engineer

19th Nov 2010, 12:06

JAR-25 !!!FOR STUDY PURPOSES ONLY!!! (http://www.fzt.haw-hamburg.de/pers/Scholz/vorschriften/JAR-25.html)

Disregarding for a moment that there are up to date copies of JAR-25, FAR-25 and CS.25 to be found elsewhere on the net, this aircraft will not be a part 25 aircraft as such.

Almost certainly the design team would need to negotiate with "the authority" a modified hybrid standard that is substantially different. This is inevitable, since what they're aiming for is neither a conventional aeroplane, nor a conventional helicopter.

For a smaller vehicle in the BA609 class, I'd expect that standard to be a composite of part 23 and part 27, for a later vehicle in the V-22 class, I'd anticipate a composite of part 25 and part 29. If it's military rather than civil, then a combination of Def-Stan 00-970 parts 1 and 2. Either way, there's going to be a requirement for considerable additional material based upon ongoing research into the aircraft class.

That said, the formal standards for cockpit design are fairly minimal in any of the civil standards and still leave room for improvement in the military standartds. Whilst they still need to be used and observed, in most cases best practice is going to be built upon research and the experienced opinions of people like John Farley. I'd personally be looking to the experiences of a range of pilots in both the fixed and rotary domains, although especially anybody who has either flown both, or flown vectored thrust vehicles such as Harrier or V22. Test Pilots are particularly valuable, because they're used to analysing their aircraft, not just flying them. I think that the National Flying Laboratory Centre at Cranfield has one person who has substantial flight test background in both fixed and rotary wing, although it's not the person previously mentioned.

You could also do worse than get hold of a copy of this book (http://www.amazon.co.uk/Helicopter-Test-Evaluation-AIAA-Education/dp/0632052473/ref=ntt_at_ep_dpt_1) which will give many useful clues. Hopefully the Cranfield library has a copy, since it's rather expensive.

G

N.B. I've just used my moderators powers to amend the title of this thread to spell "cockpit" correctly - it was irritating me.

glum

22nd Nov 2010, 16:08

Piltdown man:

"I'd also like an autopilot interface that makes it easy for you to fly the aircraft rather than the other way round."

Er, could you expand on this? Surely the autopilot is meant to fly the aircraft?

"I'd also like indicator lights above the mode selector buttons on the glareshield."

As in, to indicate which mode it is currently operating in?

WillDAQ

22nd Nov 2010, 19:35

This wouldn't happen to be a project with significant industrial involvement from a certain UK/Italian based manufacturer by any chance?

If so then simple words of advice:

(1) Don't assume that technology already implemented in fixed wing aircraft will be of low risk to introduce to a rotary wing design. There are some important gotchas lurking under the surface in terms of technology that doesn't translate well.

(2) Don't rely on high tech solutions for certification. You should be able to switch off all of your clever assistance systems and still provide the pilot with basic if degraded controls. The point being that you then don't have to certify all the clever stuff to the same standards of criticality. Eliminating the rudder pedals is not a good idea.

error_401

23rd Nov 2010, 04:06

I wish all aircraft manufacturers gave so much consideration to the "workplace" of a pilot.

I'd love to see:

The engineers set up a mockup of their cockpit in plain daylight outside. Then sit there from 05:00 LT in the morning and stay put for 8 hours. Do the same from 14:00 LT until 22:00.

Get your secretary to bring a cup of coffe every hour and inquire about your well-being every 20 minutes. (you will be amazed to find out how badly placed door surveillance can be.) Do the same and simulate the automatic door opening failed so one has to get out of the seat every 20 minutes or so without hitting aircraft controls.

Individual heating controls would be my #1. One always sits in the sun and the other freezes his feet off because A/C duct temp is 0degrees C.

Sun is a major issue all the time. A transparent possibly gray sunshade to even look through in approach without distortion and color changes.

Windows which are up do date and have no filaments but coating for the heating. No distortion on any window.
Previous posters pointed out how important sun shading is.
All windows heated to avoid freezing your outboard shoulder at night. Sun shades do the trick as well.

I'd rather have 6 EFIS screens in order to be able to monitor 2 status pages on systems independently.

Seats shall be electrically operated with manual backup. Should have enough travel to comfortably get in and out. Not to mention ergonomy of the seat itself. Eventually vented as in the luxury cars? Headrest. Reclinable to comfortable napping position.

Enough stowage. Try it out in a mockup once with the same stuff you carry when getting off a plane such as a carry on bag (crewbag) coat, hat, jacket, then try to hang it in the cockpit without getting in the way. Where does the hat fit? Where does your laptop go?

Waste bins Airbus style. Power outlet 12V.

Oxygen masks with long enough lines to reach over one seat at least - but make sure it doesn't get in the way. Place masks eventually overhead in order that nothing can drop into the mask compartment.

Headset plugs overhead so that the cable is out of the way. Seats built in a way that cables do not get stuck anywhere.

Controls which give limitations but I can oversteer if need be as described by Pilot DAR.

More in detail. Not an issue in recent designs but a thought: Parking brake setting and releasing from both positions. Steering always on both sides.
Interconnected flight controls (electric/electronic/mechanical). Auto throttle not auto thrust! Visible trim. Eventually a trim audio tone indicating trimming in one direction over x seconds. So you know what the autotrim is doing.

Overhead panel with switches in the system diagram (standard today).

Maybe more. If it is valuable you may PM me to get more ideas.

I assume that the handling of controls in normal and abnormal situations is not an issue and always has to be possible.

John Farley

23rd Nov 2010, 19:55

If GtE will permit such thread drift.

I made no input to the F35B design.

I was asked my opinion about flight test matters re the X35B.

Personally I do not agree with asking for a supersonic level flight capability with a tactical aircraft because doing so will compromise and complicate very many aspects of the design.

However, if the customer insists on supersonics then I am sure there is no better way to do it than with a shaft mounted fan holding up the front end.

JF

glum

23rd Nov 2010, 21:05

The engineers set up a mockup of their cockpit in plain daylight outside. Then sit there from 05:00 LT in the morning and stay put for 8 hours. Do the same from 14:00 LT until 22:00.

Get your secretary to bring a cup of coffe every hour and inquire about your well-being every 20 minutes. (you will be amazed to find out how badly placed door surveillance can be.) Do the same and simulate the automatic door opening failed so one has to get out of the seat every 20 minutes or so without hitting aircraft controls.

ABSOLUTELY!

I have spent enough hours on the flight deck to know how damn tedious the little things are. I even dismantled the flight deck door during one flight as it wouldn't open at all from the inside! The joys of old aircraft...

I assume that the handling of controls in normal and abnormal situations is not an issue and always has to be possible.

Um. I suspect this depends on the definition of 'handling of controls'. By definition in a fly-by-wire aircraft there is a computer between you and the control surface, so providing the computer (at whatever level of redundancy it has dropped to) is still working, then you will still retain control in all situations yes. This also implies it will respond as a fully fledged control system, with all the flight-envelope protection etc that the 'top level' provides.

As I understand it, the A380 has completely removed mechanical connection, using 4 channels of computer to provide the neccessary level of redundancy to meet the safety requirements.

On our little tiltrotor, it may turn out that we do not have the space / weight to provide 4 seperate channels - the conceptual designer has imposed a weight limit of 64kg on the entire avionics system. Yes, we laughed too...

ICT_SLB

24th Nov 2010, 00:39

"On our little tiltrotor, it may turn out that we do not have the space / weight to provide 4 seperate channels - the conceptual designer has imposed a weight limit of 64kg on the entire avionics system. Yes, we laughed too... "

My guess is that if you look at,say, one of the integrated VLJ Avionics fits, you should be getting down around that range EXCEPT for the Power Drive Units needed to actuate surfaces and, of course, the rotor or nacelle tilt. A lot of current Autopilots already have the equivalent of four Flight Director channels. MEM sensors give the equivalent performance of much larger gyros - look at what's contained in an Integrated Standby Instrument - Air Data Computer, PFD & Attitude sensors all in about 2kg. Also, if your aircraft is small, you won't have the burden of long wiring runs & the production breaks necessary in larger types.

A comment on Flight Control Panel indications - most current panels do have light indicators for engaged FD mode with some also having two so the pilot can verify that both left & right channels are selected correctly. Sadly the "schematic" type of system control panel has died with the introduction of cheaper & easily configurable synoptics on EICAS. The latest screens also allow the pilot to call up the information decks he wants and position them within the larger display unit - effectively giving many more than six EFIS.

stilton

24th Nov 2010, 00:40

Please excuse the thread drift.

Thanks for the reply John.

The Stovl F35 does seem today to be the epitiome of too much 'gold plating' and the resultant, heavy, slow and extremely complicated Aircraft has nothing on the relatively simple, rugged Harrier.

It is still impressive what the Harrier achieved in the Falklands with the FRS1 (who knows what will happen now) and it has always been a premier close air support and ground attack aircraft.

It is a great shame to think what could have been developed with further funding. personally I think the 'ski lift carriers' and the Harrier Force were an exceptional value and a potent one for the RN. Their absence is a great and irreplacable loss.

glum

25th Nov 2010, 07:28

This wouldn't happen to be a project with significant industrial involvement from a certain UK/Italian based manufacturer by any chance?

Er, not that I'm aware of. Care to expand?

(2) Don't rely on high tech solutions for certification. You should be able to switch off all of your clever assistance systems and still provide the pilot with basic if degraded controls. The point being that you then don't have to certify all the clever stuff to the same standards of criticality. Eliminating the rudder pedals is not a good idea.

I do understand your position, but we are encouraged to look ahead and not simply do what has been done before - anyone can copy - just to get an aircraft certified.

If we cannot dream a little, come up with new ideas and then analyse them drawing a conslusion based on solid research and engineering then we aren't really 'masters' of our science, and have fallen short of earning an MSc.:ok:

WillDAQ

25th Nov 2010, 11:36

Er, not that I'm aware of. Care to expand?

Ah ok, kind of a long shot.

I do understand your position, but we are encouraged to look ahead and not simply do what has been done before - anyone can copy - just to get an aircraft certified.
True, but the business case for including all the toys from the start rarely looks healthy. All of the investment is up front when you have no revenue stream, then once the aircraft is in production you lack a growth and development plan.

If we cannot dream a little, come up with new ideas and then analyse them drawing a conslusion based on solid research and engineering then we aren't really 'masters' of our science, and have fallen short of earning an MSc.http://images.ibsrv.net/ibsrv/res/src:www.pprune.org/get/images/smilies/thumbs.gif
Oh definitely, but I assume at the end of this you're looking to become an engineer, and engineers need to thoroughly assess financial viability.

Genghis the Engineer

25th Nov 2010, 11:40

If we cannot dream a little, come up with new ideas and then analyse them drawing a conslusion based on solid research and engineering then we aren't really 'masters' of our science, and have fallen short of earning an MSc.:ok:

Well said - and we should all remember that your objective in doing an MSc is not to come up with something that will actually fly, but to demonstrate that you've learned as much as possible and could potentially apply that learning to real-world projects later on.

G

sycamore

25th Nov 2010, 14:11

Glum,(I`m sure you are too young to remember the Radio program !),you might want to look at the `Rotorheads` forum for some other ideas....

glum

28th Nov 2010, 14:03

Good call, the single engine tiltrotor thread is very interesting!

glum

4th Dec 2010, 09:42

For those who've shown an interest, here is the initial CAD model of our V10:

http://i19.photobucket.com/albums/b183/Dave_ett/Stuff/V10red.jpg

John Farley

5th Dec 2010, 16:56

You might like to move the tailplane down the fin a tad so that you can put it at the large LE up angle that will be needed during some stages of the transition.

glum

6th Dec 2010, 20:47

Really?

I know very little about structural design, aerodynamic loading and the like but I will pass on your observation to the professor who drew the concept!

Genghis the Engineer

6th Dec 2010, 22:10

I'd also check the calculations on your tailplane volume coefficient - looks visually quite low to me, which could give you longitudinal stability and control problems: solveable technically with FBW, but there's really no reason to. In this application you are better of with something that has reasonable natural stability - you've no real need for combat level standards in manoeuverability.

Darrol Stinton's books "Design of the Aeroplane" and "Flying Qualities and Flight Testing of the Aeroplane" will lead you easily through the calcs.

G

John Farley

6th Dec 2010, 22:33

It is not about any of the topics you mention.

It is just about thinking how the rotor slipstream will blow over the tailplane at intermediate nacelle angles and how its angle to the fuselage datum will have to be adjusted to keep its angle of attack within a sensible range. Call it aeronautical common sense if you will.

Or you could just look at any tilt wing or tilt rotor aircraft that has flown in the past or is flying today and observe where their horizontal tail is in mid transition.

It even applies to helicopters that use a horizontal tail.

As to passing on my comment to your Professor I would bet money he can't understand why nobody in your team has yet pointed out his deliberate mistake.

He is trying to get you to think!

ICT_SLB

7th Dec 2010, 03:01

Glum,
There's a picture of the CL-84 here (http://www.aviastar.org/helicopters_eng/canadair_dynavert.php) which shows what John's saying. Overall your model looks a lot like a proposed update of the Dynavert in the 1990s that didn't get past the drawing board stage (or the BA609).

glum

7th Dec 2010, 07:49

John Farley "He is trying to get you to think!"

Oh he certainly does that!

John Farley

7th Dec 2010, 15:56

Good - that is what we like to hear!

There is a great career to be made as a specialist of course and these days many jobs in industry are done by teams of specialists. However one way to make yourself stand out from the other specialists in your area is to have a decent generalist education as well. Cranfield is one of the better places to get that so fill your boots.

In the flight test business teams of specialists can easily run into trouble if an event occurs in the air and the team managing that flight does not include the relevant specialist who can appreciate the implications of the event. This happened to me in the US where they have some of the best specialists in the world but are not so heavy in generalists.

When I asked for the sideslip limits on a .8M point I was doing (after the aircraft started to go very sideways) the test director said there was none and I should press on. I asked him to check with base - same answer. I refused to do any more and landed. As I climbed down the ladder I was met by an RAF Wing Commander UK observer who told me in no uncertain way I could not treat the US folk that way. As a UK alien when I entered the debrief room you could have cut the atmos with a knife. I used a loudspeaking telephone on the table to speak to the structural guy who had designed the back end he told me what the limit was - they checked the aircraft instrumentation and sure enough the point I had stopped at was right on the 80% fin strength line (beyond which you needed to use an instrumented fin)

Of course now the atmos changed totally and the specialists all wanted to know how I realised that we should stop when there was no trials paperwork that said so. I explained I had received a good generalist education in the business of aeroplanes.

Sorry you probably did not want to know all that

Tallsar

7th Dec 2010, 19:02

Well said John...please don't ever go away!:ok:

Cheers

glum

7th Dec 2010, 20:14

Sorry you probably did not want to know all that

I absolutely want to hear - all advice from a pro is worth listening to.

I spoke to the guy who's designing the tail, and apparently the horizontal stab is sufficiently high so as to be clear of prop wash. He does want to increase the size though, as his calculations seem to indicate it is too small in some manouevers...

John Farley

7th Dec 2010, 22:05

If you consider the slipstream to be a tube of fast moving air the diameter of the prop rotors that may be so. Sadly that energetic tube of air will induce flow at say 1.5 or more times the prop diam. Admittedly it will not be as fast as the core flow but it will still represent a huge downwash at the top of that fin and to take the longit control sting out of that you will have to align the tailplane LE up.

The reason helicopters with a small tailplane have to put that at a big LE up angle during transitions is similar (since that the tailplane is not actually under the rotor itself). Air is quite viscous and works to reduce any simple shear between high and low velocities.

BTW I believe that marked shear stresses produce a lot of the noise associated with jet engine exhaust. As a result nozzle design features try to encourage the mixing between the jet and the surrounding air to reduce shear related noise. Here you might like to increase the actual shear and so minimise the effective diam of the rotor's influence but I suspect nobody knows how to do that.

Gleavage

8th Dec 2010, 01:22

I would like an iPod dock

Northbeach

9th Dec 2010, 01:05

Concerning the HUD (Heads Up Display)

The display system shall have a means of turning the display completely off without taking your hands off the throttles and/or tiller.

Immediately following a normal evening/night landing the information lit up in the HUD has very little relevance, it’s done the work assigned and played its part, but now it clutters up and competes with the runway, taxiway, and signage lighting on the airport’s surface.

I want to completely clear the display without taking my eyes off where the jet is headed. I don’t want to look down for the “clear” button. It would be a much better design if I could turn it off with a tiller, left horn of the yoke or throttle button.

Northbeach

ICT_SLB

9th Dec 2010, 03:24

Northbeach,
Not sure quite why you'd want to clear the HUD just because you're on the ground. Most current HUDs will provide taxi speed/acceleration/decell cues and runway status (EVS) with future(?) developments such as TNASA to give positive taxi direction.

Glum,
If you consider the deep stall phenomenon on a T-Tail aircraft, I'm not sure there's such a tail geometry that can be outside of the prop wash/wing influence. The caveat being that I've only been forced to work on & program Stall systems for such birds - I'm not a Flight Scientist.

Easy Street

9th Dec 2010, 06:57

Northbeach,

Perhaps your HUD symbology could be automatically repositioned higher up the glass shortly after weight-on-wheels (ie when the attitude or velocity vector are no longer relevant)? This would avoid interference with airfield lighting. An easily-visible groundspeed readout is very useful during a rolling landing and when taxying at night. The heading tape can also be useful in reduced visibility to confirm you're taking the correct taxyway!

Some HUDs use auto-brightness sensors to adjust the symbology brightness without input from the pilot. My experience of these is somewhat mixed and it can be quite uncomfortable when the symbology incorrectly fades from view at a critical moment! A simple solution is to include a manual HUD brightness control wheel as one of the "HOTAS" switches and this is worth considering. It doesn't have to be in a 'prime' position but it is certainly handy to be able to adjust without removing hands from controls. This would also allow pilots easily to turn the brightness to zero if they didn't want the symbology on the ground.

If your tilt-rotor is to have military application then don't forget to include a countermeasures dispense button somewhere on the stick. Automatic systems are not foolproof yet! A 3-way transmit button (Com 1, Com 2, Simulcast) is useful for military flying as well; the handling pilot may need to communicate on ATC and on a formation frequency in rapid succession.

glum

9th Dec 2010, 19:10

More good input gents, thanks.

We're actually going without a HUD since there isn't any spare room on the overhead panel and very little on the coaming / behind the flatscreens to mount it. Perhaps equally importantly, HUD design isn't particularly new and there isn't a huge benefit in learning to design one (or copy someone else's!).

However... We have elected to develop single pilot ops. The cockpit will retain two full sets of displays / controls as it was felt the certification process would be impossible if we chose to go with a single pilot installation.

This throws up some huge challenges, not least what happens when the pilot is incapacitated! The general thrust at this point is to have the aircraft autonomously land at the nearest available airfield, so defining the sequence of events from the take-over (what constitues pilot unable to control?) through declaring an emergency, requesting a new flight plan and then controlling the aircraft all the way to stopping on the ground is bending our brains in whole new ways.

We will also need to automate checklists, provide voice prompts, voice recognition, some decent algorithms and on-screen assistance for system failures.

Part of the process will be writing certification rules to present to the EASA / FAA to demonstrate the problems, and the solutions we have designed to mitigate the risks associated with them.

With firms such as Embraer declaring their intention to work towards SPO within the next 10-15 years, I feel it is high time a University gave this more than a brief consideration.

Gleavage

11th Dec 2010, 23:30

Spoken automatic checklists? So its almost like there really is another pilot.

glum

12th Dec 2010, 13:30

That's what we're developing yes. :)

Piltdown Man

13th Dec 2010, 09:56

Here are some really menial WIBNI's (wouldn't it be nice ifs):

Sunscreens that can be positioned single handed
A charging point for laptops, mobile phones, Electronic Flight Bags etc.
Rubbish/wastepaper bins that can be easily emptied and cleaned
A dimming system that enables ALL cockpit lights to be dimmed
Somewhere to stash active paper work and a fixed clipboard
Somewhere to stash old paperwork
Somewhere to stash manuals
Digital manuals with a proper index so you don't have to go to the one above
A guidance panel with lights above the selected mode with values shown in windows on the panel as well as in the PFD/ND
Automatic altitude arming (change the altitude and have ALT armed automatically)
A live VS wheel
Heading/Altitude/Speed knobs that you twist to arm, push to hold and pull to select.

PM

glum

13th Dec 2010, 15:51

Piltdown Man,

Could you expand on these a little?

"Digital manuals with a proper index so you don't have to go to the one above"

Not sure what you mean by this? Would a [BACK] button solve the problem?

"A guidance panel with lights above the selected mode with values shown in windows on the panel as well as in the PFD/ND"

What values?

"Automatic altitude arming (change the altitude and have ALT armed automatically)"

Is this a safe thing to do? Would you never pre-select an altitude ahead of time, then arm it at the appropriate time?

"A live VS wheel"

Not sure what you mean by this: live even when not under autopilot (or flight director) control?

Piltdown Man

13th Dec 2010, 19:45

No problem:

A digital flight manual is all but useless unless it has a good index. If the index and/or table of contents is useless you end up getting the paper manuals out of their stowage.

I now fly an aircraft without the heading, altitude or speed shown on the guidance panel. They are only shown on the FMA in the PFD. To select a heading you have to look for the correct knob (one of ten) and then turn it whilst you are looking at the FMA. And it's a pain in the bum. Most aircraft have the heading, altitude and speed selection shown on the guidance panel. But not the Embraers! Bloody Honeywell!

Additionally, when you select HDG, Speed or ALT (ie. press the button to engage the mode) the selection is ONLY visible within the FMA windows and not on the guidance panel. Again. a pain in the arse.

Altitude arming: I think you have it. If you dial in a different altitude, you want it armed, not ignored. So bloody arm it! In a Fokker 50 you have to arm (select ASEL) every altitude. A pointless pain with serious implications if you forget. On the Fokker 70/100 you dial in the next altitude and as soon as you select a new vertical mode, the next altitude will be captured on reaching. Neat!

When I move the V/S I want the plane to go up or down. Why should I have to press another yet another button to say I want to use V/S when I have already moved the wheel? And yes, live in all FD modes.

You may get the impression that I'm a fan of Fokker 70/100's and you'd be right. I also really dislike the battle that I have to do with the crap installed in the Embraer 190. If Honeywell peddle these poor sods more of the same crap they have sold in the past, God help those who fly in them and under them if they ever become single pilot.

Oh and could I have a cloud light as well please. Something that would illuminate a cloud well before I get to it at night. Not quite a laser but a well focussed light that would reflect off a cloud at say 1/2 mile?

PM

glum

13th Dec 2010, 21:57

Oh and could I have a cloud light as well please. Something that would illuminate a cloud well before I get to it at night. Not quite a l@ser but a well focussed light that would reflect off a cloud at say 1/2 mile?

I'll have a word with a chubby friend of mine, think he's got a solution to that - known as the HIRL.

High Intensity Rudloph Light. ;)

Very interested in your feedback on the hdg bug, as I have been woking towards something like the Garmin 5000 - single remote touchscreen for all inputs to the systems. From what you're saying you'd rather have a knob adjacent to the screen - or would a repeat of the HDG at the point of entry be enough?

Piltdown Man

15th Dec 2010, 16:39

...or would a repeat of the HDG at the point of entry be enough?

Would be lovely. But only have the value display if armed (ie. pre-set) or active. If unarmed or in-active show dashes.

PM

A37575

16th Dec 2010, 05:47

Re cockpit design. Straying slightly off that specific subject for a few moments, but I wonder if people are aware of an interesting aspect to cockpit check list design. Back in the Seventies my airline which had a couple of new Boeing 737-200's had the services of a former Boeing test pilot who was involved with the design of the 737 cockpit and associated operational checklist items. After receiving the first of our two 737's our company had added several more items to the published 737-200 checklist.

It was pointed out by the test pilot that we may have to employ a flight engineer since the 737 was designed to be flown by two pilots and the inclusion of several more checklist items invalidated the two crew concept.

He explained that research revealed there was a certain limit to the number of items a two crew could cope with. Any more than that, a third crew member such as a flight engineer was needed.

That is why various functions were automated in the 737 to reduce the number of eye movements, switch selections etc. The auto seat belts function and auto-switch over of the pressurisation system were two cases in point.

By adding more items, the integrity of the two pilot operation is compromised since the additional workload is unnecessary. I wonder if those check pilots responsible for adding further items to the manufacturer's published check list are aware there is a lot of planning and thought gone into the original checklist design for a particular aircraft type. Indeed, some of these checklist items may be the result of accidents or incidents in the past and designed to mimimise the chances of mistakes happening again.

Having observed in the simulator the sometimes extraordinary number of call-out's required of the crews of Airbus types it seems that continual verbalising of what they see in terms of instrument indications or what are considered as airmanship items such as company SOP's, could be considered as superfluous to the actual flying of the aircraft. Fly by mouth is an apt description. Sorry about the thread drift

Piltdown Man

16th Dec 2010, 08:41

A37575 - I think you are spot on!. Designing a cockpit that minimises the number of items on a checklist and callouts in flight can only be "good thing."

Oh, and another request. Allow NAV or HDG to be armed on the ground but make a sub-mode of heading like "Take-off Track" the active mode as soon as take-off power or G/A is selected. Then, at a suitable height such as 400' automatically engage the armed mode (unless manually selected earlier) or stay with "Take-off Track" if no lateral modes are armed. Keep this mode until another lateral mode is selected. Calculate the value of "take-off track" to the average track made good say between 30 and 80 kts or use the ILS "track" for the G/A.

For altimeters, built a separate barometric setting knob with QNH window shown next to the knob. A wise person would also enable Feet & hPa, Feet & Inches, plus metric. Personally I'd do that with a rotary selector but make sure that the values are converted precisely when the knob is moved We don't want to spill our tea. Have a STD knob which toggles between the pre-set QNH and STD.

PM

Pilot DAR

17th Dec 2010, 23:17

Thanks A37575, those are very useful thoughts.....

glum

21st Dec 2010, 07:28

Why would you have metric altitude? Doesn't everyone fly on feet or flight levels?

Piltdown Man

21st Dec 2010, 11:28

Why would you have metric altitude? Doesn't everyone fly on feet or flight levels?

If only that were true! The former Eastern Bloc and China fly using metres and don't forget that our US cousins use inches to set their altimeters. And I'm sure you don't want exclude this potential market for the sake of a knob, so to speak.

PM

glum

21st Dec 2010, 12:29

Ah ok, thanks. Absolutely not! China is likely to be a huge market in the not too distant future...

ICT_SLB

23rd Dec 2010, 03:10

Glum,
FYI most current EFIS include Metric Altitude & HPa/Inch Hg options by program pin and/or menu selection so you don't necessarily need another switch.

Piltdown Man

23rd Dec 2010, 10:21

ICT-SLB: I disagree. If ever you fly between an Imperial and Metric FIR, you really need the Switch or Knob. Pin or software programming is OK for switching between Knots and Kilometres, but a change in altitude measuring has to be capable of being done in the air (as well as on the ground) - so you HAVE to have the switch. Failure to provide the switch/knob means that any operator flying between these two types of FIR has to have additional paperwork.

PM

ICT_SLB

24th Dec 2010, 01:37

Piltdown,
On the majority of Rockwell Collins EFIS (at least on aircraft built by my employer) the Metric Altitude is up permanently as a numeric read out when programmed - but not the main scale, which I would guess, is what you would prefer.

Piltdown Man

24th Dec 2010, 22:41

I can see your point. But as you fly from imperial to metric land (or vice versa), you really want to be able to select your actual cleared level rather than the closest (and arguably perfectly legitimate) equivalent. It's a bit like PC's in their early days - Having only a # instead of £ because the manufacturer couldn't really be bothered to spend a dollar or two to cater for a foreign market really annoyed customers.

PM

glum

16th Jan 2011, 01:09

New term, new questions!

I'm now working on the single pilot operation, and trying to come up with some flowcharts for 'action in the event of pilot incapacitation' during the seven stages of flight:

1. Pre flight Taxi
2. Take off
2. Climb out
3. Cruise
4. Descent
5. Approach
6. Land
7. Post flight Taxi

Taxi is easy - put the brakes on, set engines to ground idle and stop the rotors turning!

Take off stage is pretty much the same providing there is room on the runway to stop. If not, proceed with take off, climb to safe altitude and request clearance to land. Once given, carry out approach and landing in accordance with local rules.

After that it gets a little tricky, as I'm not sure what the proceedure for in flight emergencies is - luckily I've never had anything serious enough to have to find a runway quickly.

I'd appreciate some help with listing the actions you would take on having an in-flight emergency which required landing at the nearest suitable airfield.

Assume there are no systems failures - at this stage just getting a serviceable aircraft back to terra firma is enough.

Thanks again for any input. :)

Glum.

ICT_SLB

16th Jan 2011, 05:02

Glum,
I thought your aircraft was a tiltrotor? So I'm confused about your takeoff scenario unless you're always going to do a rolling takeoff - not how I've see Ospreys operate. I would suggest you might want to consider subdivisions of your basic phases - for example many transports' takeoff configuration warning (& thus pilot actions) have a break point at 100kt. For a VSTOL aircraft, I would think in or out of ground effect or vertical or rolling takeoff could all have a bearing on pilot actions. Other major ones would be available Autopilot modes & capabilities - Emergency Descent mode for example. I've never worked on a VSTOL but it's bad enough sorting out the CAS logic for a fixed wing so you've got my sympathy - they'll be making you work this term!

Genghis the Engineer

16th Jan 2011, 11:11

At the risk of being a bit glib, the typical actions in the event of pilot incapacitation in a single pilot aeroplane, are to lose control resulting in an accident.

If you are looking at some form of reversionary logic to design into your AFCS in the event of a pilot ceasing to make any inputs to the controls,then this is pretty complex and I think that what you're going to need to do is sit down with a pilot and use their knowledge base to sketch this out in the format that you need. If you hadn't already made contact with the test pilots at NFLC then this is probably the time to do it.

You could get a lot from the checklist and manual used by a good flying school. Staying at Cranfield, I'd suggest that you could do worse than, say, strolling along to Bonus Aviation and buying a copy of theirs for either an Arrow or a Seminole - which should be a pretty good source of reference in seeing how pilots are programmed to handle these actions, since your machine needs to essentially do the same. (I suggest them, because I know their checklists and they're quite well written, complete and easy to follow.)

In a nutshell however, I think that if you are really trying to automate actions in the event of pilot incapacitation, all of 2-5 will be basically an expansion on:

- Squawk emergency
- climb/descend to safe height (just above MSA is probably optimal in most parts of the world.
- Orbit in position for a couple of minutes whilst making some RT announcement of intentions with timeline
- Divert to nearest available (or a pre-programmed) instrument runway
- Make automated instrument approach and landing.
- Stop on the runway and shutdown.

No.6 will just simplify to:

- Squawk emergency
- Make RT announcement of pilot incapacitation
- Make automated instrument approach and landing.
- Stop on the runway and shutdown.

If you are going to design something like this into a flying machine, you absolutely need some form of cockpit announcement and pilot override - the pilot may have perfectly good reasons for not making control inputs, or a dead-mans-switch may fail, and a conscious and capable pilot needs to be able to override the computers and continue to direct his own destiny.

You might also want to consider incorporating some alteration to cockpit air supply / pressurisation in the event of apparent pilot incapacitation.

G

Tester07

16th Jan 2011, 11:42

I would suggest that you take a look at some of the automatics that Garmin are certifying on their AFCS at the moment.

Also auto recovery systems for sudden depressurisation are becoming quite popular with more than one avionics company.

Pilot DAR

16th Jan 2011, 12:05

I think that the flowchart for actions in general, for a heavily automated aircraft (which I'm sure your project would be) would not change a lot in the case of pilot incapacitation. You'll be adding the common sense actions required to get the aircraft to the quickest suitable landing site for mediacal assistance, but not while causing increased risk to the flight.

We fall back to the basic prime directive of safe flight, in its order of importance: Aviate - Navigate - Communicate. Do only as much as you can, assuring that aviating is always being done first. If half your crew resource is lost, a few things may be delayed, while the remaining crew member flies safely. The rest will fall in place. If an accident happens in the mean time, it was going to happen anyway. It will be less severe than if control of the aircraft was lost. Once you squawk 7700, you probably just took care of navigate and communicate all in one.

So, stepping aside from the "checklists" for a moment, I'd be concentrating on the aircraft design, if there is an option to embody provisions to minimize the impact of such an event.

If the tiltrotor is in any phase of flight where thrust is being directed anywhere other than directly horizontal, an accidental control input of any consequence is probably unrecoverable, but design the provision in to minimize the impact if you can.

If the aircraft is fly by wire, the design opportunity exists to allow one pilot to take control away from the other. Obviously, for the sake of crew harmony, this would be used only for emergency, but it's worth having. Two ways of accomplishing this: Big red "I've got it" button (but that requires an additional action), or more subtly, defining a "normal" control motion range, and an "emergency" motion range. Whoever moves their control into the emergency range last, has total control of the aircraft. So, if pilot A falls over the stick, and pushes it full travel, pilot B's instinctive reaction wil be to apply a whole lot of input to his stick to correct the situation. Pilot A's stick never got emergency authority, as it got in the range first. A's stick maintians control until B's stick goes into emergency range, then the computer realizes that A's input was for the wrong reasons, and B's is trying to return to controlled flight. This could be linked to the computer's knowledge of the aircraft attitude. B has total control until things change favourably.

The other thing my wish list would have built in, would be an "other" pilot controlled motor on the inertial reel of the shoulder harness, so it could be used at a suitable speed to winch an incapacitated pilot upright in the seat, harmlessly away from all the cockpit knobs. Car seatbelt "pre-tensioners" do this in harmony with airbags to some degree, but for different reasons.

Other than that, if the incapacitated pilot is not interfering with the safe operation of the aircraft, the flying pilot should be expected to continue to fly the aircraft safely (or he really should not be there). If the systems are so complex that he is having trouble coping with the workload, just give him more time. As I said, 7700 goes a long way in this regard, and if someone on board is incapaticitated, it just became a "medivac" flight, which has the highest priority in flight.

Back in the 80's I was a very inexperienced right seat pilot in a Piper Cheyenne, when the pilot suddenly took ill. Although he maintained conciousness, and was not in dire circumstances, he withdrew from flying for the remainder of the flight. I took my time, used the normal checklists, and there was no problem. Yes, if something had quit, the tension would have ramped up quickly, but we do what we can. This is not a safely threatening event, if pilots are well trained.

glum

16th Jan 2011, 12:14

It is a tiltrotor yes, but part of the requirements are for a conventional take off and landing.

Our outline plan for actions after the pilot has turned a funny colour is to have the thing broadcast a distress message, plot a course to the closest suitable airfield and head there asap.

The problems are overcoming the communication issue. It's easy enough to transmit a pre-recorded message, but we're not sure speech recognition is sufficiently mature to interpret instructions from air traffic about clearance, runway etc.

We don't want to rely on a ground controller to fly it like a UAV, as this would be costly to support for any purchaser. Plus the opportunity for terrorist takeover of course...

Pilot DAR

16th Jan 2011, 12:50

Is this a single pilot, or two pilot aircraft? I'm presuming that for the cost, and intended role of a tiltrotor aircraft, there would be two pilots. Assuming one pilot is left to fly, I don't see the need to design in that level of automation. (though I accept that this is just an exercise).

If this is a single pilot, turned UAV exercise, it's beyond my "pilot" mind....

glum

16th Jan 2011, 16:40

It's being designed for single pilot ops. In some roles - military and SAR - two would be required, but otherwise it is intended to fly with only one - hence the clever avionics to cope when the only pilot can't fly.

It will already be fully autonomous from taxi off to taxi in, but it's a whole other ball game when trying to get certification for it to fly itself without a ground controller.

exairman

16th Jan 2011, 19:40

Why rule out remote "wifi" control of the ac? Understand the unauthorised access bit and wireless comms is not my expertise, but what about limiting the range of the transmission of the signals FROM the aircraft?

A ground station could reach the aircraft at long range, but if that remote station has to transmit back a randomly generated access code transmitted from the aircraft AND the range of the aircraft transmitter is only 50ft, then the station has to be near by - in other words another aircraft in close formation even if only to get initial remote control?????

Remember not a comms expert just a random browser!

glum

16th Jan 2011, 22:17

We ruled out remote control as it would require a global network of operators standing by whenever the aircraft was flying with a single pilot.

Plus the aircraft already has autonomous everything, so it seemed sensible to use the equipment already fitted (and probably controlling the aircraft 90% of the time anyway).

Thanks for your interest though!

Pilot DAR: Really like your idea about the control column.:ok:

Genghis: The pilot over-ride is a slightly tricky one. We initially thought of a PIN number, but the lecturer reckons in the heat of a systems malfunction, the last thing the pilot needed was to try and bring to mind a PIN number! Far better to have a couple of manual over-ride switches or buttons, which would require simultaneous operation (perhaps).

Genghis the Engineer

16th Jan 2011, 22:34

Genghis: The pilot over-ride is a slightly tricky one. We initially thought of a PIN number, but the lecturer reckons in the heat of a systems malfunction, the last thing the pilot needed was to try and bring to mind a PIN number! Far better to have a couple of manual over-ride switches or buttons, which would require simultaneous operation (perhaps).

All you need is an audible warning and an illuminated "I'm still alive" override cancel switch, possibly guarded, in clear view. You really don't want this to be multi-control or like a security system - it really must be as simple as possible - the pilot the aeroplane thinks is asleep may be busy troubleshooting something, or planning a weather diversion with a manual or chart open on his lap.

G

glum

16th Jan 2011, 22:53

Sure. Our concern with something that simple is the possibility of a passenger trying to over-ride it...

We have a guy working on the IVHM system who will devise the method for determining pilot incapacitation.

Having seen some of the guys near the end of a ten hour red eye, I wish him luck on working out who's alive and who's not!

Genghis the Engineer

17th Jan 2011, 07:09

Sure. Our concern with something that simple is the possibility of a passenger trying to over-ride it...

Easily solved with a placard on the back of the pilots seat:

PASSENGER NOTICE: If pilot is incapacitated, aircraft will land on its own. Do not touch controls.

There's a great temptation to make things overcomplicated - all that does is create extra opportunities for things to go wrong.

G

glum

17th Jan 2011, 16:02

Repeat to self:

"Just because you can design it, doesn't mean you should. Perfect is not always better." :)

MurphyWasRight

20th Jan 2011, 13:58

glum writes:

Sure. Our concern with something that simple is the possibility of a passenger trying to over-ride it...

We have a guy working on the IVHM system who will devise the method for determining pilot incapacitation.

Having seen some of the guys near the end of a ten hour red eye, I wish him luck on working out who's alive and who's not!

This is similar to detecting drunk drivers and preventing them from starting the car. (Breathalyzers don't work 100% - think pre-bar balloon of breath)

A hypoxic pilot could in theory respond to a very simple challenge:

I .. must .... push ..... button .......... silence ............... damm "pilot gone" alarm.

There is a lot of research on the problem, one of the simpler method is one I implemented in college (way back when) for a project car:

Computer displays a random 4 digit number for 1 second, example 4125 then blanks display, wait 1 second then prompts driver.

Driver has 2 seconds to key in the number in reverse : 5214.

Very easy to do when sober - not so when over the limit.

Unless in on the secret highly unlikely a passenger would gues what to do.

(The testing was the best part of project... times are from memory and may be off a bit)

glum

20th Jan 2011, 18:55

Hmmm, interesting concept. Not sure a stressed pilot who's perhaps dealing with an engine failure would have the spare capacity to start reading and reciting numbers back though!

We have to assume a worst case scenario really, so something simple but not obvious to someone who didn't know the correct buttons / sequence.

MurphyWasRight

21st Jan 2011, 14:49

Glum writes:

Hmmm, interesting concept. Not sure a stressed pilot who's perhaps dealing with an engine failure would have the spare capacity to start reading and reciting numbers back though!

Totally agree, most of the time the system could rely on a much simpler method of sounding an alert when no activity for a time (dependant of phase of flight, longer in cruise etc) that would be automatically cancelled by any reasonable action by pilot such control input, mode change on fligth director, cancelling an alarm etc.

This would also cover most of the busy with emergency cases, although most of those would probably generate sufficient activity to prevent the alarm in the first place.

It would also be a good idea to put in logic/HW so the programm could self check that it was indeed receiving control inputs to prevent making things worse in the case of multiple system failures.

I was thinking more of the case where there might be a few random non-logical inputs (given flight phase) by the pilot where the system would need to determine if the pilot was hanging by the straps and bumping a control or simply distracted by wrestling with a new flight roster program on a laptop.

Search for Minneapolis (SP?) overflight if you dont catch that last reference.

glum

8th Feb 2011, 09:43

Thanks for the inputs and reading suggestions.

We've gone for a simple two switch setup:

One Two-position gated switch, for Dual / single pilot ops, which will effectively switch the monitoring & takeover system off when two pilots are operating.

One guarded momentary switch, for use by the pilot if the system attempts to take over when he's fine. It'll be a simple system 'reset' he can use in case of system glitch. If the fault persists, then he has the option to switch the system off permanently as per dual pilot ops.

glum

8th Feb 2011, 09:50

The latest picture:

http://i19.photobucket.com/albums/b183/Dave_ett/Stuff/Sparrowhawkjpg.jpg

glum

10th Feb 2011, 08:17

And the flight deck so far...

http://i19.photobucket.com/albums/b183/Dave_ett/Stuff/Flightdeck.jpg

glum

11th Feb 2011, 00:30

All opinions are valid!

The idea behind this layout is actually to make things more basic. 3 screens, two touch-screen controllers and an autopilot contoller.

I feel that the modern flight deck (A380 for example) is just a maze of buttons and screens, with huge potential for switch-pigs. Do pilots really want all those options? Do they need them?

Why show you stuff you don't need to know, and why not show stuff you really do?

I'm trying to work towards taking things back to VFR where possible - afterall, that's the most basic flying isn't it?

If we the avionic designers can give you the pilots enough SA that even flying in crappy weather at night is as easy as doing it on a sunny day, then I think we've achieved our goal.

If you still want to make flying hard, then buy a Pitts Special and have some fun!

glum

13th Feb 2011, 10:26

in this day and age it would be seen as 'criminal' and unsafe to not have computers doing most of the work for you

The problem is the perception of danger by the general public. It's mad when you think that about 800 people died in flying accidents last year, yet 100 a DAY die in road crashes in the USA alone.

If our record was that bad, no-one would ever fly. Fact is that computers have made flying safer, and a fare paying passenger wants to reach their destination - it's just transport to them, not a fun part of the holiday.

We can still do better though, 2 confirmed CFIT events last year, and a possible further 7 pending investigation conclusions. This is where I fear the designers have got it wrong...

Thanks for the encouragement! :ok:

ICT_SLB

14th Feb 2011, 03:18

"If we the avionic designers can give you the pilots enough SA that even flying in crappy weather at night is as easy as doing it on a sunny day, then I think we've achieved our goal."

Glum,
If that is your goal, then I would reconsider your lack of a HUD especially if single pilot. The increased SA from an EVS (http://www.youtube.com/watch?v=Z6SahHsdvJI&feature=player_embedded#at=29) has, literally, to be seen to be believed. It also gives you an additional dispatch possibility with the main display failed - without a co-pilot I would question the usefulness of the No. 2 screen.

glum

14th Feb 2011, 09:52

Would love to have a HUD. The main reason for omitting it is the lack of space - both overhead and on the coaming. This thing is tiny! Secondly we've got such a small allocation for weight, that we can't afford to have 'luxuries' like HUD in the standard fit.

Would a blended display of synthetic vision and IR camera not be good enough to fly even though it's head down?

For the military and SAR versions, helmet mounted optics would be the answer, but we can't really envisage bizjet pilots wanting to wear them for day to day operations.

All the screens are identical, so for dispatch it would be a quick job to swap them, and the avionics behind them will reconfigure should a channel fail.

From my research, display screens now have an MTBF of around 16,000 hours, so I'm fairly confident that screen failure would be a very rare occurance.

Genghis the Engineer

14th Feb 2011, 11:06

I have to agree about the HUD, or something HUD-like. If I was flying single pilot operations, potentially at low level, then the situational awareness benefits would be very much appreciated. The head-down screens (compared to older analogue instruments) will help, but flying a complex machine like this on a mission (civil or military - consider possibly SAR missions, into a remote site, onto a ship...) a pilot very much needs to keep their head up as far as possible.

Personally, I'd not worry massively about making a pilot wear a helmet in an aircraft like this - the issue however is the large cost and complexity of introducing such a system, which is far in excess of that for a HUD. Plus, the major part of the computing power still needs to be put in the aircraft somewhere. That will be crippling.

In that cockpit, the obvious HUD positioning would probably be in the roof, similar to the B787 dreamliner...

http://farm2.static.flickr.com/1192/769175223_480e194008.jpg

A further thought - have you considered the cockpit view around a 360°x360° sphere. It's never going to be perfect, but it's not clear to me that you've got quite what you want there. View ahead and above is good - but have your crew got adequate view downwards and rearwards for operations in the hover?

A further further thought - which seat is your Captain - left (like an aeroplane) or right (like a helicopter); your control layout and logic may need to reflect this reality.

Yet another thought - that central pillar in the cockpit, splitting the two windscreen sections, is just begging to have your CWP in it. Aviation Enterprises did something similar in their Magnum, which worked really well.

G

glum

15th Feb 2011, 16:12

a pilot very much needs to keep their head up as far as possible.

Hmmm, damn! Will give this some more serious thought, but I suspect it's a little late in the project - we have PDR in three weeks!

large cost and complexity... computing power... That will be crippling.

Good points, this this is already madly expensive. Perhaps a HUD will suffice.

In that cockpit, the obvious HUD positioning would probably be in the roof, similar to the B787 dreamliner...

Trouble is there's so little room. For reference, the flight deck is only 1.5 meters high from floor to ceiling!

A further thought - have you considered the cockpit view around a 360°x360° sphere.

Yes, and I believe the structures guys have plotted the views - as far as they were able due to the constraints from the concept design. We have forward, downward and area cameras so that the pilots will have as much SA as can be achieved.

A further further thought - which seat is your Captain - left (like an aeroplane) or right (like a helicopter); your control layout and logic may need to reflect this reality.

Left. Or maybe right. It's an ongoing discussion! I've gone with left as I'm more familiar with fixed wing, but is there a reason right would be better? The control stick and throttles will be as per helicopter, so right hand on stick, left on throttle.

Yet another thought - that central pillar in the cockpit, splitting the two windscreen sections, is just begging to have your CWP in it. Aviation Enterprises did something similar in their Magnum, which worked really well.

CWP? Central warning panel?

Couldn't find any pics of the inside of the aircraft you mentioned, but I can imagine what you're getting at. Aside from the attention getters, I hadn't planned on having any seperate warning panel, just the central display.

ICT_SLB

16th Feb 2011, 01:31

Glum,
Not worked on one myself (all ours are either Rockwell Collins (Flight Dynamics) or Thales projection HUDs) but the BAE Q-HUD (http://www.baesystems.com/ProductsServices/bae_prod_eis_q_hud.html) was the one I had in mind. Best thing has to be that there's no Overhead Unit.

Must agree with you, a CWP is not a normal fit if you have an EICAS display.

glum

16th Feb 2011, 07:26

Ooh like that a lot!

Thank you.:ok:

ICT_SLB

17th Feb 2011, 03:40

Glum,
You realise that there'll be a price to pay for all this expertise - a link to your paper when it's finished. Perhaps our Moderator can be persuaded to add it to the Sticky at the top of the forum.... BTW what sort of Autothrottle are you going to have or just a simple APR for when one engine fails? I'm assuming that everything's cross-coupled mechanically.

glum

17th Feb 2011, 20:13

You realise that there'll be a price to pay for all this expertise - a link to your paper when it's finished.

Yes of course! :ok:

BTW what sort of Autothrottle are you going to have or just a simple APR for when one engine fails? I'm assuming that everything's cross-coupled mechanically.

Ah that gets interesting! There is a drive shaft running between both gearboxes yes, although in normal use it will carry no load. If an engine fails then the shaft will transmit power from the still running engine to the inop side, giving us up to 30 minutes flight with the increased output required from the engine.

It cannot autorotate.

Since both engines are running full FADEC systems, the autothrottle is pretty easy to implement.

However, I believe that with OEI the autothrottle will trip off, since the guys simply do not have the time to write the code. It will obviously require a whole new set of parameters to work against. Obviously given time then that mode would be catered for too.

Tinstaafl

18th Feb 2011, 05:39

My pilot-based thoughts. Some have been mentioned by others too.

It needs sun visors. That looks like a lot of window area, heavily raked so difficult to get the sun & heat out of your face. Not just darkened visors either. Proper opaque things that can be positioned pretty much anywhere. It's bloody annoying flying into a facefull of low sun and the only available screens can only dim the glare a little. Or can't be positioned to cover the particular spot that the sun is in. In all the aircraft I've flown, what I would have loved are blinds on each window that can be pulled down. If they can go all the way to the bottom of the windows and have the exterior facing surface reflective then they can double as sunscreens while parked.

Why overhead throttles? Sure, we all get used to throttle or trim knobs mounted above but I find it less comfortable than a lower, pedestal mounted set.

Numerous cockpit lights, individually controlled, both ambient & spot. Make sure at least one narrow beam spot per pilot seat can shine right where approach charts & paperwork will be held or worked on. That light needs to have a narrow field to reduce glare. A light on a curly cord is nice too - there's always spots that one would like to look at that's not directly exposed to light. One of the few things I really liked about the Islander. I could even shine it out the window to look for icing. Oh, and forget incandescent bulbs. Use LEDs.

A spot to stick approach plates/charts while in use so they can be seen without obstructing the displays or interfering with operating switches & buttons. It must allow for bound documents, not just single sheets. Not everyone uses Jepps. and their annoying 'take the page out, put the page back in every single time you wish to use a chart' system. OK if two crew and the PNF can do the task but a right pain single pilot.

Lots & lots & lots of storage space/bins/drawers for manuals, charts, paperwork and the like, jacket, pilot's flight bag (pilot's bag reachable from the seat), pen holders, place to put a cup that can capture spills. How much empty space is there in the central pedestal? Same question for those side pods.

Make CB panels grouped & mapped to represent the system(s).

Make sure seats can move far enough rearwards so that feet can't reach the pedals. Good for when a pax. is in the other seat or you're the PNF or even just want to stretch for bit.

Don't agree with replacing rudder/anti-torque pedals with twistable grips. The input is still needed so why move the inceptor? You make one part of the body have to work harder or with more complexity while leaving the previously used body part doing nothing.

Don't do what Garmin did with the terrain alert on their GNS430/530 kit. The bloody alert occludes the entire map requiring an input to remove even though the advisory box also has a warning too. It's a right pain in the bum. You can disable the terrain alert, but only after each avionic power on then it defaults back to enabled after each shutdown. Unfortunately that disables all terrain warning, including the less obtrusive one in the advisory area. It's not that I don't want the alert, I just don't want that big bloody alert blocking the screen I want to look at.

Use knobs where possible, not a keypad. Keypads are a pain while bouncing around through turbulence. At least a knob can be gripped for support while using it. Make sure it has decent detents & resistance to movement or overshooting the desired selection happens. Don't use push-push selection for either-or functions. Use push-pull so the force applied acts as feedback. Also it means you can apply force contrary to the undesired choice to make sure it doesn't happen. I flew an aircraft once with an altitude warning selector that was push-push to choose 100' or 10' increments while rotating the knob to select value. Bloody hated it! I was always bumping it during use and having to go back to undo the selection in the unwanted scale. It was the one that crystalized my dislike of too-soft detents too.

Definitely a hard switch to select altimetry scale. Also while on about hard vs soft switches: A hard switch for any function that gets used a lot eg heading bug, nav. course and the like. Transponder codes too, in a way. having to drill through menus to bring up a transponder setting page isn't on. OK I think to have TXDR select hard button (or semi-permanent soft button) then use a multi function input knob or pad

Auto-altitude arm. Once I enter the next alt. in the panel, I shouldn't then have to arm the thing. Starting the climb or descent should then activate the mode. A Kingair 200 I fly is annoying that way. If the arm button isn't selected then it will happily bust an altitude even though the altitude has been set in the alerting system.

Fuel gauges that aren't in the pax. field of view. Or at least, aren't obvious. Makes pax nervous to see the guage getting low - especially if there's still another couple of hours left to fly. They don't know how much fuel is in other tanks but they've just seen the rate the gauges moved towards empty. Piper's PA31, for example, has two large fuel gauges mounted in the center overhead panel and looking straight back at the pax compartment. There are four fuel tanks but the indicating system only shows the tank selected. Pax aren't happy when you're trying to use all of the aux. fuel because it *looks* like the plane is low on fuel, never mind the other 3 hours left in the main tanks. When I fly that type I have to dick around on the last 1/4 of each aux with one engine selected back to main so at least one guage shows plenty of fuel while the other engine uses the last of its aux., then select that one to main so the 1st engine can use its remaining aux.

Shouldn't have to be said but all switches reachable from the captain's seat. That B200 I mentioned earlier has a hot amenities bar but it's impossible to switch on or off from the captain's seat. OK if flown with a co-pilot but not when single pilot. I suppose I could switch it on as a climb into my seat, pull the CB prior to start, and then reset the CB after start - but I shouldn't have to.

Make sure avionics databases can be upgraded using standard SD or USB memory devices. USB preferably due to ubiquity. I should be able to bring the memory device from my PC to the plane, plug it in and have the databases updated. None of this serial port + laptop dragged to the cockpit to download the update. Also the ability to upload flight plans generated on a PC and download monitoring information such flight & engine data for later analysis. Monitoring data must be in an open format, not some closed binary requiring special software to access eg CSV plain text instead of M$ .XLS or similar. Just about anything can open or import a plain text file.

Any hot battery buss courtesy lights should also have master switch near the exit so that they can all be switched off just prior to shutting the door after parking. Some the aircraft I fly have hot buss courtesy & cockpit light switches scattered through out the aircraft. The number of times I've had to go back through the plane to make sure *every* hot light is off so the battery doesn't discharge... Also any automatic courtesy light needs to have a selectable auto/off/on switch eg in baggage compartments. Sometimes I need or want to leave the door open without the light on, other times I don't want the light on at all.

XM weather (or equivalent)! I consider it to be the biggest advance in weather safety since onboard Wx radar. US centric, I know but that's where I am now & satellite weather is truly wonderful. The number of times I've either been able to do a flight where previously I'd have cancelled or delayed, or been able to save hundreds of track miles by having the big picture + immediately available TAFS & METARS.

Probably heaps of other things I've forgotten but have sat there wishing it was so, or not so.

PS: An aux. audio IN jack please, with automatic muting. I have this nice little MP3 player that works really well in the aircraft I fly...

ICT_SLB

20th Feb 2011, 04:57

Tinstaafl said:
"Numerous cockpit lights, individually controlled, both ambient & spot. Make sure at least one narrow beam spot per pilot seat can shine right where approach charts & paperwork will be held or worked on. That light needs to have a narrow field to reduce glare. A light on a curly cord is nice too - there's always spots that one would like to look at that's not directly exposed to light. One of the few things I really liked about the Islander. I could even shine it out the window to look for icing. Oh, and forget incandescent bulbs. Use LEDs."

LEDs have so low a power requirement it should be possible to have the required burn time and light output without trailing cables - just pull it off the charging plug.

"A spot to stick approach plates/charts while in use so they can be seen without obstructing the displays or interfering with operating switches & buttons. It must allow for bound documents, not just single sheets. Not everyone uses Jepps. and their annoying 'take the page out, put the page back in every single time you wish to use a chart' system. OK if two crew and the PNF can do the task but a right pain single pilot."

I would suggest an Electronic Flight Bag (http://www.esterline.com/avionicssystems/ProductsServices/Aviation/DisplaysVisionSystems/ElectronicFlightBag/tabid/2273/language/en-U) (EFB) would be better especially for a single pilot. You can also use it as a convenient additional weather display, preloaded routes, maps, live airport picture (including own ship), weight & balance.....

Tinstaafl

20th Feb 2011, 05:56

My preference is for a light on a cable. Can't get lost that way, although a secondary LED torch with a charging station is a good idea.

EFB data subscription can be expensive and aren't easily approved in some parts of the world. They also can't remove the inevitable paperwork so I still would want to see a narrow spot for writing, reading checklists (if they're not electronic), manuals, paper based information for non-EFB airstrips and the like.

glum

22nd Feb 2011, 19:04

It needs sun visors…If they can go all the way to the bottom of the windows and have the exterior facing surface reflective then they can double as sunscreens while parked.

Like this idea a lot. I’ve passed the info on to the cockpit structure designer…

Why overhead throttles? Sure, we all get used to throttle or trim knobs mounted above but I find it less comfortable than a lower, pedestal mounted set.

They’re just ‘conditioning’ levers. Three settings: Ground idle, flight idle and auto – at which point the main throttle comes into play.

Numerous cockpit lights, individually controlled, both ambient & spot…Oh, and forget incandescent bulbs. Use LEDs.

Absolutely. Although with all the terminal charts etc available on the main screens the intention is that you won’t really have to use paper maps. I do know there are always charts to write on, notes to take and other books to look at though, so lighting is being addressed.

Have you used finger lights?

A spot to stick approach plates/charts while in use so they can be seen without obstructing the displays or interfering with operating switches & buttons.

As above, we’re intending to have all charts on the main displays, so there isn’t a need to have others clipped to something. Are we being naïve?

Lots & lots & lots of storage space/bins/drawers for manuals, charts, paperwork and the like, jacket, pilot's flight bag (pilot's bag reachable from the seat), pen holders, place to put a cup that can capture spills. How much empty space is there in the central pedestal? Same question for those side pods.

Storage space? Hmmm, it’s a pretty tiny cockpit so I’m not sure how much room there will be for ‘stuff’ but I do appreciate pilots need storage. I’ll speak to the cockpit structure designer about using some of the space in the side pods…

Make CB panels grouped & mapped to represent the system(s).

CB’s will be controlled through the touchscreen, so of course will be grouped by system. Mapped to represent the systems will need some thought…

Make sure seats can move far enough rearwards so that feet can't reach the pedals. Good for when a pax. is in the other seat or you're the PNF or even just want to stretch for bit.

Nice thought, but I don’t think there’s room - I’m not entirely convinced the crew will be able to get in without climbing over the chairs at present! Max endurance is only about 3 hours, so hopefully not too onerous.

Don't agree with replacing rudder/anti-torque pedals with twistable grips. The input is still needed so why move the inceptor?

Save weight, and for most of the flight they’re not used - all roll commands have cross coupling performed by the Flight control system. We’ve actually decided to keep the pedals as it was felt a step too far on such an ‘odd’ aircraft as a tiltrotor. I can however see them being removed in the future, since the playstation generation manage perfectly well with a twist joystick…

Don't do what Garmin did with the terrain alert on their GNS430/530 kit. The bloody alert occludes the entire map requiring an input to remove even though the advisory box also has a warning too.

Good heads up.

It's a right pain in the bum. You can disable the terrain alert, but only after each avionic power on then it defaults back to enabled after each shutdown.

Safety reasons I suspect.

Use knobs where possible, not a keypad. Keypads are a pain while bouncing around through turbulence. At least a knob can be gripped for support while using it.

We’re basing our design on the Garmin G3000, and having seen several video’s the touchscreen does seem pretty easy to use due to the raised band round the display. Additionally there are knobs which can be used in place of the touchscreen should you prefer to, of it fail.

Don't use push-push selection for either-or functions. Use push-pull so the force applied acts as feedback.

Ah, more good advice!

Definitely a hard switch to select altimetry scale. Also while on about hard vs soft switches: A hard switch for any function that gets used a lot eg heading bug, nav. course and the like. Transponder codes too, in a way. having to drill through menus to bring up a transponder setting page isn't on.

Ok, I was considering a separate control for the IFF since I appreciate the code does change often.

Auto-altitude arm. Once I enter the next alt. in the panel, I shouldn't then have to arm the thing.

I planned on having the rotary to set the height, then press the knob to activate it (like my BMW sat nav). Text will be orange when not active, and green when active.

Fuel gauges that aren't in the pax. field of view. Or at least, aren't obvious.

Hmmm, they get displayed at the top of the centre panel along with the engine info. Maybe we should move this to the bottom of the display…
Shouldn't have to be said but all switches reachable from the captain's seat.
Naturally. Especially for single pilot ops! There really aren’t many switches anyway…

Make sure avionics databases can be upgraded using standard SD or USB memory devices. USB preferably due to ubiquity. I should be able to bring the memory device from my PC to the plane, plug it in and have the databases updated.

Absolutely how we’re doing it.

Monitoring data must be in an open format, not some closed binary requiring special software to access eg CSV plain text instead of M$ .XLS or similar. Just about anything can open or import a plain text file.

Interesting thought, I’ll pass that on.

Any hot battery buss courtesy lights should also have master switch near the exit so that they can all be switched off just prior to shutting the door after parking. Some the aircraft I fly have hot buss courtesy & cockpit light switches scattered through out the aircraft.

Yeah, I worked on the L1011, which has a ‘ground bus’ switch by the door which brings the lights & sockets on for cleaning crew.

Also any automatic courtesy light needs to have a selectable auto/off/on switch eg in baggage compartments. Sometimes I need or want to leave the door open without the light on, other times I don't want the light on at all.
Ok.

XM weather (or equivalent)! I consider it to be the biggest advance in weather safety since onboard Wx radar. US centric, I know but that's where I am now & satellite weather is truly wonderful.

Do you think it feasible to have the weather fed to the FMS such that it can reroute automatically around bad weather? We have a couple of guys working on that…

PS: An aux. audio IN jack please, with automatic muting. I have this nice little MP3 player that works really well in the aircraft I fly...

We have an icon for music on our touchscreen… ;o)

Great feedback, thank you.

Tinstaafl

23rd Feb 2011, 00:16

Finger lights don't work when your hands are holding onto controls, setting switches & the like. Still need a narrow beam onto a viewing/work area. Whilst screen based charts are good, not all airstrips have charted procedures or diagrams. Companies that operate in the bush will usually have their own paperwork with information about the strip or landing area. Can include diagrams, textual description, limitations, mandatory items etc. Ditto things like search & rescue patterns. I used to be qualified in Australia as a civil SAR pilot. One of the things we did was drop smoke/flares, stores & rafts, following an instrument-like pattern to get accurate timing & positioning in winds. Need to be able to read that stuff. Paper maps & charts are still useful, even with electronic versions. If this is planned to be a useful utility aircraft then you have to expect it will spend a lot of time off the beaten track.

A feature request that could help: The ability to upload scanned charts/documents for display on the screen. Even better if the software allows the uploaded chart's scale to be entered + some reference point lat/longs so that the GPS position can be overlayed.

Another software feature request: Using the stored charts be able to plan or enter a route by touching cumulative waypoints on the screen, designate some as intermediate landing/refuel points and have a box-out form appear with known data & new data to be added (eg fuel upload). While doing the planning have a range ring on display that's calibrated to known or entered fuel on board and pre-set fuel flow. In flight the range ring could use measured FF against known quantity & grounds speed.

Also avionics based: Weight & balance calculations. Automatic if appropriate sensors are present, or manual if not.

Climbing over seats is surprisingly common so that's not a bother. If you can't find a way to extend the seat rail aft then try to find a way to have adjustable rudder pedals. If it's not pressurised then extending the footwell a bit into the nose shouldn't be too hard. Beech, in their Bonanzas & Barons have rather useful collapsible pedals so pax. can't interfere when the pedals are stowed. Another option could be to space the L & R pedals apart, leaving a gap between them that would give a bit of extra leg room.Sitting in a cramped space for two or three hours without being able to stretch one's legs is unpleasant & distracting. Even worse if you have a whole day of it.

Red/green mode lights for the altitude selector is nice but I'd still rather have the act of selecting the altitude automatically arm the mode, with it becoming active once a climb or descent is commanded.

If the throttles are to be on the pedestal, I'm not sure I like the idea of the condition levers being elsewhere.

If the CBs are to be operated remotely instead of physically, how will you guarantee redundancy so that no matter what the pilot can ensure that power was cut to the problem circuit. Thinking of fires here, and how they can completely disable remote switches if they burn through the control wiring. I know I like to be able to have the all-but-guaranteed ability to kill the power through any circuit to just by by reaching over & pulling the CB.

Hard switched code selectorsfor the TXDR is preferred but I could live with a softswitch as long as it was always able to be be accessed ie a permanently displayed TXDR switch on the screen that, when activated, sets the data intput buttons/knobs to IFF code entry. Still need a permanent IDENT button. Shortcuts/fast access to the emergency code(s) could be considered too. Garmin have on their transponder equipment

Meant to ask, is it pressurised? If not, then how about being able to open the windows. Not just a crack or a storm window but the whole thing wide open. Not inflight, but on the ground for ventilation and even egress. Again, have a look at Beech Bonanzas & Barons: Both mid fuselage windows are top-hinged & have a mechanism that holds the window open a small amount (but I'd like a more) and also pull a pin to release the limiter & the window swings up fully to be an emergency exit. Your design's crew side windows could be forward-hinged...

I don't think autoflight routing around Wx is feasable. Weather, traffic & ATC demands are too variable. And no matter what the avionics show, Mark 1 eyeball is still a final arbiter of what's out there. The number of times what I see out the window is worse than the XM or radar shows and choose not to go there, or the XM or stormscope shows something that isn't there. XM information can be old too. It's not real time.

Are fuel tanks in the wings? How does the crew get up there to refuel or check the caps? A couple of permanently extended or flip out steps in the fuselage would be nice eg Cessna's step kit for their high wing singles. The steps don't have to be large - just enough for a toe purchase while climbing onto the roof. Didn't need steps in an Islander because I could stand on the R. pax door edge & pull myself up onto the wing using the R. engine cowl & roof. Also what about checking engine oil pre-flight? Will the dipstick/sight guage be accessible without a ladder?

Just some more thoughts....

Good luck with your project.

glum

6th Mar 2011, 11:17

Well we had our PDR last week, with examiners from Airbus giving feedback on the 80 designs it's taking to develop this little puddle jumper.

Overall they were pleased with what we've achieved, though observed that we hadn't put enough emphasis on safety - at least in our presentations.

Guess it's easy to run away with our creative sides, and let slip the bonds of reality!

Kerling-Approsh KG

15th Mar 2011, 18:20

Forgive me, as I may be arriving late at this party, but have you considered fitting TSAS?

Some years ago, I had the pleasure of trying out NASA/USN's TSAS. It consisted of a pad installed on the pilot's seat and a waistcoat worn by the pilot, connected to a small pneumatic system.

ABSTRACT:

Pilots and astronauts do not experience spatial disorientation in normal day-to-day terrestrial activities. On the ground, the perception of position and motion is determined by central nervous system integration of concordant and redundant information from multiple sensory channels (somatosensory, vestibular and visual) which collectively yield veridical perceptions. In the acceleration environments experienced by pilots and astronauts, the somatosensory and vestibular senses frequently present false but concordant information concerning the direction of gravity or down. When presented with conflicting sensory stimuli, it is normal for pilots and astronauts to experience episodes of disorientation. Visual instruments and displays developed over the past 70 yr have not solved the problem. A simple solution to maintain spatial orientation is to provide true information using the same sensory channels we use so successfully on Earth.

METHODS:

The Tactile Situation Awareness System (TSAS) developed by NASA and the U.S. Navy uses a matrix of mechanical tactile stimulators (tactors) applied on the torso and limbs to convey orientation cues (e.g., gravity vector) in an intuitive fashion to the skin. A series of in-flight experiments to validate and test a variety of tactile displays and concepts has been carried out in both helicopters and fixed wing aircraft.

RESULTS:

Pilots were able to fly complex maneuvers with no instruments or outside visual references (blindfolded) with less than 20 min of training. Recovery from unusual attitudes solely by tactile cues was trivial. Lab tests have shown the TSAS improves performance under conditions of high workload.

CONCLUSIONS:

When orientation information is presented via intuitive tactile displays spatial orientation is easily maintained in altered sensory conditions including unusual acceleration environments.

abstract ends

I've written before that I initially perceived this to be snake oil... However, the system enabled me to hover a medium helicopter with which I was not familiar, in simulated white-out conditions, with great accuracy (I wasn't current in rotary wing flying then, either). The system was programmable through various modes according to the task, for example, hover, transition, tactical weapons modes, etc.

It works by providing tactile stimuli, and the immediate way such stimuli are transmitted to the brain is central to the system's effectiveness. Response is immediate and instinctive.

For example, if you set it ip for a six foot hover, and you sink slightly, the seat pad taps the pilot's posterior at a rate dictated by the deviation; drift left, and the left side of the torso receives a similar cue.

I wrote before: "our tactile senses are enormously overlooked in flight deck design" and I stand by those words now.