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Sunfish
14th Sep 2015, 21:40
I am in the delightful process of laying out an experimental instrument panel. I have some general human factors knowledge and am discovering one or Two things (switches grouped and spaced 25mm apart as per U.S. military study).


There is a Skyview EFIS, backup altitude and ASI a radio (or perhaps Two), magnetic compass on top and transponder to be fitted as well as warning lights and stuff.

I would welcome tips, suggestions references and the like especially any "don't do this" gotchas.

Simple, inherently obvious placement and good design is the objective, not some overly complex copy of an F18 cockpit.

tail wheel
14th Sep 2015, 22:19
Does this help?

http://www.concordesst.com/inside/cockpittour/graphics/flightcontrols.jpg

:p

Squawk7700
14th Sep 2015, 22:25
Radio(s) up top as close to eye level as possible. Otherwise you will struggle to read the small numbers, especially if you have to lower your glasses to see them.

If money is tight and you are on a budget, a good dual watch radio is pretty much as good as two radios.

Hook up some switches for interior lights as it's easier now than later. Fit a solid led strip light on the roof, they sell them at Jaycar for caravans and the like. Great for in the hangar where it's dark and if you need to work on your aircraft or find something on the floor.

If there is a built in instrument light available such as in the ASI or compass, make sure you connect it.

Missile switches for Rotax mags or a high quality keyed ignition.

Hasherucf
15th Sep 2015, 02:12
Decent thickness of the panel. Seen two panels in Cessna recently that radio racks were falling out or cracked through supports . They were fine back in the day when they had only two Comms. 0.063" or 0.080" . T3 is best but if its a home built I would go commerical

If you are CNC cutting the panel and you are tight for space consider cutting a perspex panel first and trial fitting the instruments.

Fit an avionics master.A guy came to me with a flat battery in an RV. He had all avionics and lights set through the one master switch. Most of his CB's were of the non pull type.

If you are a tall pilot remember the glare shield can obscure your view of some instruments . Mostly the audio panel.

Use self retaining hardware , don't rivet your racks in . Yes that does happen.

The Mid continent USB chargers are awesome. Great if you considering using an ipad or phone.

Consider powder coating or using screws with plastic washers

Just random thoughts :)

QFF
15th Sep 2015, 03:57
Missile switches for Rotax magsAre these the ones with the red guard? So presumably on is in the down and guarded (cover closed) position, to prevent accidentally turning mags off?

Another option would be the switch where you have to pull it out to move it from one position to the other - don't know what that's called...

Squawk7700
15th Sep 2015, 04:26
Are these the ones with the red guard? So presumably on is in the down and guarded (cover closed) position, to prevent accidentally turning mags off?

Correct, you don't want to switch them off accidentally, although I have seen a builder with them around the wrong way!

tecman
15th Sep 2015, 04:51
Don't know what sort of aircraft it is but I would say make sure you provide a decent glare shield over the panel, noting Hasherucf's comment about sizing it properly. I find a number of experimental class displays are just about useless for me because of washout and viewing angle effects (I'm not that tall, but tall enough to compromise optimum viewing angles with some randomly placed displays).

I would also provide a well-placed and solid iPAD mount, articulated enough to minimize the specular reflection for yourself and a range of other pilots. Quite a challenge in a bubble canopy, I found.

And having an aircraft with a fairly easily accessible panel reminds me what a joy that is. If you can't manage a one or two piece swing down option, at least a removable top and/or good side access will save you many building words (and skinned knuckles) in the future.

USB chargers (already suggested) and spare breakers are other obvious inclusions, as well as an appropriately placed power outlet for your ANC headphone buggery box. Mine sits in the centre compartment between the seats.

Don't forget to separate out the clean and dirty d.c. supplies and returns, or you'll curse the spurious whines and whirs for evermore :)

Ultralights
15th Sep 2015, 07:27
do it digitally..

https://pamuva1.smugmug.com/Other/SmugShots-1/i-FThxwh9/0/M/IMG_5230-M.jpg

https://pamuva1.smugmug.com/Other/SmugShots-1/i-RKwFqKg/0/M/IMG_5221-M.jpg

All switches moved to an overhead panel, so, not so easy to accidentally hit. and you have to make a conscious decision to look up and operate a switch.

Eyrie
15th Sep 2015, 10:27
An F-18 cockpit is actually pretty simple. MacAir did a great job on it especially the HUD.
I'm sure you can find a picture of it on the web.
Based on personal experience of 30 minutes in the sim.

john_tullamarine
15th Sep 2015, 12:36
Keep in mind that, from a Standards POV, you are looking at a design certification matter and you would be well advised to seek some guidance from an appropriate certification TP.

I see you are in Melbourne - if you wish I can put you onto a local top bloke (also a PPRuNer) whose background for this stuff is impeccable.

gerry111
15th Sep 2015, 13:06
Don't forget the coffee cup holders. :O

Centaurus
15th Sep 2015, 14:08
Install a large artificial horizon directly in front of the pilot.

Not one of these fancy tiny EFIS Garmin types which looks like a small V upside down designed as flight director surrounded by all sorts of other information. An artificial horizon that stands out like dog's balls if you get into cloud and into an unusual attitude. :ok:

Sunfish
15th Sep 2015, 20:46
Reading 20.18, I need an "airspeed indicating system", a magnetic compass and an altimeter.

I thought maybe a Dynon pocket panel or suchlike might be a backup but that only uses GPS data for (ground) speed and altitude so I will fit the 2 1/4 inch units I have.

While the skyview is the primary display, I have a well found fear of "the blue screen of death" because its happened to me on a yacht with multiple GPS, gyro compass, fluxgate compass, autopilot etc. and it can be extremely confusing. I want to be able to switch the bugger off if necessary and revert to paper map, clockwork ASI and Altimeter, watch and magnetic compass.

I'm working in plywood now and have the throttle, mag switches, main and auxiliary fuel pumps in a row workable without releasing the grip on the throttle. Prop control switch and controller similarly accessible above.

Hand will have to come off for start and flap actuation. Right hand on stick does trim, PTT autopilot disconnect.

Will fit an avionics master.

I have plenty of "missile switch" covers but as they face "downwards" and toggle switch actuation is "up" for On they seem only really useful for emergency backup battery power and start power switches that are normally off.

The Lane A, B, and fuel pumps will have mil spec switch guards though. Somewhere I have "lift" up lever toggle switches andI might use them for lanes A and B if I can find them.

The skyview is going to sit in a 0.63" frame with four quick release fasteners on the corners. That gives me simple access to the back of the panel which would otherwise require contortions.

dubbleyew eight
16th Sep 2015, 10:11
sunny I have a panel that is steam VFR. utterly reliable.
beyond that I have an artificial horizon.
I would reiterate the comment of centaurus.
put an artificial horizon in the centre of your panel.
put the other vfr instruments around it and the engine monitoring instruments away in front of the passenger.

there is a rare book on fatal accidents in curtin uni library (or was).
one of them shows the post mortem face of a pilot.
very neatly impressed in his forehead are the row of switches that punctured his head and caused his death.
the photo of the cherokee dashboard shows an identical row of switches right at the bottom of the panel by his knee.
he was found sitting in his seat with a properly done up lap sash seat belt.
under high deceleration the human body is capable of elongations that would be normally attributed to the octopus.
make sure that whatever is in front of you you would be prepared to smack your head into. because one day you actually may.

think carefully about how you set out your panel because one day that care may save your life.

Aussie Bob
16th Sep 2015, 10:31
Reading 20.18, I need an "airspeed indicating system", a magnetic compass and an altimeter.If you are day VFR then that is all you need :). Keep it simple, look out the window. Put the savings into flying said machine.

Centaurus
16th Sep 2015, 13:42
If you are day VFR then that is all you need . Keep it simple, look out the window. Put the savings into flying said machine.



Keep it simple, look out the window. Sod's Law guarantees that one day and despite you best intentions, you will find yourself in lowering visibility with no visible horizon and no artificial horizon installed in your LSA. Unless you are a superb and current pilot flying on limited panel then you will be dead in 45 seconds so the experts say.

Sunfish
16th Sep 2015, 20:36
Centaurus, one of the modes of Skyview, which I already have, is a full screen display. This will have to suffice for a clockwork AH:

http://www.aero-news.net/images/content/sportav/2009/Dynon-SV-D1000-1009b1.jpg


Another is the classic steam gauge layout:

http://static1.squarespace.com/static/5324c2c8e4b0137cd27d6ff8/t/55a5e38ee4b06913f20ab755/1394952822719/SkyView-Touch-EFIS-with-six-pack_PFD_web.jpg

I also have the autopilot servos.

Talking to some more knowledgeable folk at Ausfly, I think I learned that the presence of such equipment represents a temptation similar to the one that has killed so many Cirrus pilots - pressing on when one should not because of misplaced faith in the automatics and ones ability to interpret them correctly.

The question then one has to ask oneself is "would I be trying to do this without the Dynon gear?. If the answer is no then land or do not depart in the first place.

Centaurus
17th Sep 2015, 14:40
Another is the classic steam gauge layout:


Get rid of that pesky V bars FD and you have a decent AH.

Re the square image. Is there an AH to be seen among all those pretty colours? Ah Yes! I see it now hidden in the terrain. If it is hard to see, then it is useless...:ugh:

Sunfish
17th Sep 2015, 21:08
Centaurus, how about one of these? Suction cup mount for when the Skyview fails? Battery powered.

http://dynonavionics.com/downloads/Dynon-D1-Top-Panel.jpg

..Otherwise it's a venturi and a vacuum AH and ditch the electronics, autopilot and GPS. I suppose I could make and fit a spring gauge ASI on the left wing strut.:E

Capt Fathom
17th Sep 2015, 21:31
Re the square image. Is there an AH to be seen among all those pretty colours? Ah Yes! I see it now hidden in the terrain. If it is hard to see, then it is useless...
Ah..if there is a terrain display, you don't need the AH!

training wheels
18th Sep 2015, 00:28
Sunny, will you be getting a mode S transponder installed? Would genuinely love to see your adventures on Flightradar24. (Or do you also need ADS-B to appear on FR24?)

Ultralights
18th Sep 2015, 06:41
doesnt the skyview have battery backup? and nice having the dynon next to the compass...

dubbleyew eight
18th Sep 2015, 07:48
Sod's Law guarantees that one day and despite you best intentions, you will find yourself in lowering visibility with no visible horizon and no artificial horizon installed in your LSA. Unless you are a superb and current pilot flying on limited panel then you will be dead in 45 seconds so the experts say.

2 points.

I have needed my artificial horizon on 3 occasions as a vfr pilot.
never regretted having one.

the 45 seconds to death is often repeated but it is rubbish.
in turbulent conditions it is probably quite correct but conditions are not always turbulent.
I ran out of safe options one night after being told some incorrect last light info.
I flew a neutrally stable Tailwind for 20 minutes in total darkness.
To my amazement there was no lights visible in the countryside, no horizon visible at all. just an impenetrable matt black darkness.
I couldn't see any of the aircraft structure around me and couldn't see a hand placed in front of my face it was so dark.
by carefully managing my head so that I was not subject to somatogravic illusions I flew by the sound of my engine note and a steady hand on the controls for 20 minutes until I was able to rescue the situation. (the moon came up)
the experience reinforces the advice given in a 1950's book on navigation.
'a pilot is not lost until he succumbs to panic and ceases to think logically.'

at about the same time a chap in NSW flew into cloud in a dragon rapide, lost it and killed 7 people.

it isn't automatically a death sentence but it can become one.

john_tullamarine
18th Sep 2015, 11:07
I flew a neutrally stable Tailwind

.. ah, a little bird which redefined directional stability for me. Only ever had the one fly with Pete Furlong yonks ago .. a couple of circuits saw my interest wane ..

Fred Gassit
18th Sep 2015, 11:25
Lots of great advice given already:

I didn't see anything regarding engine instruments.

I substituted an engine monitor for the traditional gauges. Cheaper than a quality set of gauges and more useful data besides.

I put in a second pressure sender (<5psi) to a big red light for the oil pressure.

Something to get me home if the monitor goes completely.

Squawk7700
18th Sep 2015, 12:15
The reason why you couldn't see your hand in front of your face is because I suspect it was between your legs.

The name is Porter
18th Sep 2015, 12:32
Copy other panels, not completely but a combination of all the panels you like. Then go to Complete Avionics on the Gold Coast to do your loom. Work out what you like and don't like. G3X was non negotiable for me, GTN750 etc. It all falls into place if you take your time and don't listen to the bull**** from others that have put stuff in, realised its crap and try and talk you into doing the same so they're not alone.

Sunfish
18th Sep 2015, 13:25
No point having an oil pressure gauge with a rotax or other high precision engine according to a modern engine expert.

If the pressure drops much at all the thing will seize. There is no gradual decay where the thing sputters and runs on 10% oil pressure, it either works at full pressure or it is about to catastrophically fail.

Fred Gassit
18th Sep 2015, 14:04
Fair enough, just run the big red light then, cheaper than the EMS at $5 from Autopro.:}

Centaurus
18th Sep 2015, 14:38
the 45 seconds to death is often repeated but it is rubbish.

Depends on your height when you lose the AH. :E

Observed an overconfident businessman who owned his own Cirrus, in a flying school "simulator" practicing holding patterns. During the holding pattern inbound turn his instructor failed the AH without telling the student. He never picked it until too late and it turned out he couldn't be bothered to practice on limited panel (Turn Coordinator) as he claimed it would never happen in a Cirrus. . Within 45 seconds his VSI was off the clock in a steep spiral dive and I can testify he would have crashed as he was clueless what to do. The instructor mercifully "froze" the simulator when all was lost.

I recall 20 + years ago reading a BASIS report of a Mooney over- flying Mildura (?) from Adelaide on very dark night when the vac pump failed; thus AH failure. He reported having difficulties with his AH and that he would do a 180 and land at Mildura. He never made it and broke up in mid-air trying to fly on the turn indicator. That 45 seconds to death wasn't far off. No turbulence - just pitch black outside and probably never practiced limited panel instrument flying.

If you don't believe me check this link: https://www.atsb.gov.au/publications/investigation_reports/1997/aair/aair199703221.aspx

Squawk7700
19th Sep 2015, 00:59
Isn't it actually 178 seconds to live?

Maybe 45 before you lose it and 178 to when you are no longer living.