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key or keyless

Stockmanreef

Well Known Member
Maybe this should be a poll, but i would like to get a feel for keyless with push start, push start with hidden key/switch, or keyed ignition.

Thanks
ken
 
Limited audience

This may be kind of like nosewheel vs. tailwheel, slider canopy vs. tip-up, or fixed-pitch prop vs. constant speed. Everyone has a preference, and for their own good reason.

I will point out that by limiting this to the RV-14 forum, you probably will get fewer replies than if you had posted it to a more general forum, like "RV General Discussion/News." Folks who have been flying RV-3s, -4s, -6s, etc. for a very long time probably have some good experiences to share.

It's a good question, and I'm interested in the replies you get. However, I'm probably 2 or 3 years away from making this decision myself.
 
I do not like key switches in airplanes. There have been too many issues and at least one AD issued on aircraft key switches.

I have been using toggle switches for the past 21-years and more than 3,300 hours. I have a spring return to OFF toggle switch that looks just like my ignition toggle switches. Most major switch manufacturers have switches in this configuration.

Toggle switches should cost less than a key switch and are more reliable.

Just my opinion.
 
Maybe this should be a poll, but i would like to get a feel for keyless with push start, push start with hidden key/switch, or keyed ignition.
Thanks
ken

Personally I don't like "key" ignitions. They do fail and the problem is that unless you test the "Off" position periodically, you won't know it's failed. By killing the engine with the mixture, the "Off" position does not get checked regularly. When you do a mag check, you check the left, right, and both positions, but not the "Off" position.

I am now in the process of changing out the key switch on my Legend Cub to toggles and push-to-start switches.
 
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I keyed the Master with a nice "jet ski" switch, and toggled the e-mags. Push button start. I like it so far...
 
My RV-10 has a key switch but I am planning for a push button type in the -14.

Ron RV8 - can you elaborate on the “jet ski” switch? I am not familiar with that other then the “marine kill switch”..
 
I considered the following

1.) Reliability - Key switch vs. toggle, I'm sure there will be many arguments on which is better and why. Gary and Mel both make good points though.
2.) Security - Cars use keys, and 765,484 were stolen in the US in 2016.
3.) Liability - What if at the ramp or a fly in some kid decides to climb in your plane and start pushing buttons. The engine may never fire but the prop will still spin, and with enough force to cause significant injury.

On good council I too put a simple key switch to the master.
 
I also put a key switch to the master and a push button start. Separate toggle switches for the ignition. I could never forgive myself if some child got access to the plane and inadvertently swung the prop. My system is wired such that even if the key switch failed after the engine was started, the engine would keep running.
 
Ron RV8 - can you elaborate on the ?jet ski? switch? I am not familiar with that other then the ?marine kill switch?..

Same idea: have a big fat sliding contact switch be the only thing connecting to the battery. Dramatic reduction in PIC confusion in case of battery fire or other electrical malfunction such as stuck starter relay. I used a 1000A marine switch, comes with removable "key" which provides minimal physical security.
 
I?ll be using a three position double pole Honeywell TL toggle switch with a lockout...(off/on/momentary start). The lockout is between off and on which will keep me from inadvertently flipping it to the off position. I?ll have a separate three position double pole toggle switch for a mag switch (off)/on/(off). I?ll be running an electronic EFI type of an ignition and really don?t need a ?mag? switch....or in this case a ?coil? switch, but I still like to have the ability to check each one independently. I may elect to install a simple little hidden on/off toggle switch under the edge of the panel somewhere that?s easily accessible to me so that I can block the power going out to the starter solenoid if the momentary start toggle is engaged. That on/off toggle would just live in the on position unless I were somewhere that I thought there may be a safety issue.

Mark
 
Thanks for the responses. I did just post to the general forum to see what more people think as rv7boy suggested.

Thanks
ken
 
When i redid the panel on my 4 i went to nice toggle switches and push button start. However for safety my starter button is only active when left mag on, right mag off and strobes on. This helps keep kids from being able to just push the starter button. Was pretty easy to wire and I would definitely do it again on my new plane.
 
On my -8, I had toggle switches on the panel for the mag & EI and a Start pushbutton on the stick. It worked perfectly, never failed, and was a joy to use. I'll use the same system on the new -14A.
 
I just have a big push button on my panel.

Who in their right mind would steal an experimental?

They are more likely to bust open you canopy and take you radios than the entire plane.
 
I have flown across the Country twice now and at each stop, left keys in the airplane - even at rural airports in Mississippi. Thinking back, that probably wasn't real smart.
 
I have flown across the Country twice now and at each stop, left keys in the airplane - even at rural airports in Mississippi. Thinking back, that probably wasn't real smart.

I use a key, and never leave it in the plane. The risk is not theft, so much as the legal doctrine of an attractive nuicence - stupid kid starts airplane, prop kills his friend, parents sue for millions. At least I make it harder to start.
 
I use a key, and never leave it in the plane. The risk is not theft, so much as the legal doctrine of an attractive nuicence - stupid kid starts airplane, prop kills his friend, parents sue for millions. At least I make it harder to start.

Does this legal doctrine apply to that the same kid impaling his eyeball on your pitot tube because, well, hes a boy and crawling under a wing or fuse is a stupid boy trick......and youre out millions despite the fact that the remove before flight tag is hangin' out his eye socket?

Of course, each to his own, and its a good hangar discussion, but I dont buy the key switch argument on a legal basis....I'm more worried about my own safety wrt key switch failure. Toggle switches for me - starter arm toggle in series with a starter engage momentary toggle. Both semi hidden from plain view but still one hand operation from the left seat.
 
Key with Button

Here's an example of a pushbutton with a key for security. Mag switches are locking toggles, key switch is a Honeywell AML series. The pushbutton is a nifty double pole momentary, with a lighted bezel from NKK. It's wired such that when engaged, one pole grounds the right mag, while the other engages the starter solenoid. That second pole and the lighted bezel get battery voltage, from the VPX starter switch output, via the key switch. In this way, the starter can only be engaged with the key on and the engine RPM below the VPX threshold. When the engine starts, the lighted bezel goes out and the button cannot engage the starter if pushed by mistake. It works great and makes my inner geek smile :D

i-rpWrZ4L-L.jpg
 
There has been a lot of advice given on this thread but one thing to keep in mind is that in a stressful situation the first thing to go is your fine motor skills, followed closely by your ability to remember complex tasks.

I can't stress how important it is to keep the process of starting your aircraft as simple as possible.
 
I can't stress how important it is to keep the process of starting your aircraft as simple as possible./QUOTE]

Totally agree. In my setup, if the engine stops, the starter button lights up and you push it.
 
paddy- that is cool. I don't know enough about electrical to wire that up.

What about a flip cover over the starter button that covers the start button after the plane is started to prevent hitting when the engine is on?
 
Button

No need for a cover. If the engine RPM is above 600, the button is inactive and the bezel light is off. When the engine stops, the button lights up to indicate that it's active again and "encourage" you to push it should you not be on the ground at the time.
 
For those who use a push button for their starter and are worried about inadvertent activation of the starter, if you also use a circuit breaker to control power to the start solenoid then a simple lock on the start circuit breaker is a cheap, easy and light solution to the problem.

I use a circuit breaker collar when the airplane is left unattended outside the hangar. When it's in the hangar it's behind a locked door so I don't worry about inadvertent operation of the starter.

An example of a circuit breaker collar - there are other types available.
https://www.aircraftspruce.ca/pages/el/circuitbreakers_locks/skyloxlockoutdevice3.php
 
No need for a cover. If the engine RPM is above 600, the button is inactive and the bezel light is off. When the engine stops, the button lights up to indicate that it's active again and "encourage" you to push it should you not be on the ground at the time.

What do you mean "when the engine stops" What triggers the light? A rpm limit value? Or does it need to be at zero rpm to reactivate? How do you wire that it pick up zero rpm?
 
I have a keyed switch (Steinair) that controls power through the push button starter. Mags (soon to be P Mags) are controlled through toggles. When I leave the plane somewhere I turn the ‘starter enable’ keyed switch off and remove the key. No kid can turn the prop, even if they were to turn on the master. If the mags are left on after shutdown, I have a piezo buzzer connected through the dual pole mag switches, powered by a 1 amp fuse hot to the battery and grounded through the white wire on my Plane Power alternator (alternator fail wire). It makes a noise after engine shutdown (ie. alternator failure) if I leave either mag switch on. This is independent of master switch position, since it’s hot to the battery. Also makes a noise before engine start with mags switch(es) on until the alternator is ‘alternating’. When I get my P Mags I’ll probably wire this buzzer to the downstream post on the master solenoid to alert me when the master is left on, since the P Mags are not hot with the master off. When working on something that requires the mag switch(es) to be on now (mag timing), or master on for EFIS work after PMag install, I’ll just pull the ATC fuse out of the holder to silence the buzzer.
 
paddy- that is cool. I don't know enough about electrical to wire that up.

What about a flip cover over the starter button that covers the start button after the plane is started to prevent hitting when the engine is on?

I agree, that does sound cool.

If I ever make it home in the RV to visit my Mom, I'll let you try mine. My starter button is oversized and no guard is needed; you really have to want to start it to push it because it has a pretty strong internal spring.

This is the button i have, only i didn't install the ugly rubber cover. 11 years and 835 and I have never wished for anything different.
 
I got a pretty good deal when I bought my RV-4 because the panel was original to '92 and in desperate need of fixing and updating. Not long after, the key switch started acting up. I wasn't quite ready for a whole panel, so I just cut out the section with the old plastic toggles, removed the key switch, wired in some B&C toggles on a small piece of aluminum, and riveted it back on. Works great for now. I'll get more elaborate with safeties when I actually build a new GRT panel.

I went with toggles because I think it is easier, safer, and more reliable than a keyed set up. I've built a few hot rod cars and always used toggles and buttons. Much simpler to source if one goes bad. And, I know a couple of folks that have lost keys...myself included.
 
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Sure is.

Personally I don't like "key" ignitions. They do fail and the problem is that unless you test the "Off" position periodically, you won't know it's failed. By killing the engine with the mixture, the "Off" position does not get checked regularly. When you do a mag check, you check the left, right, and both positions, but not the "Off" position.

I am now in the process of changing out the key switch on my Legend Cub to toggles and push-to-start switches.

I agree with Mell on this one. But it is what you like and want in your aircraft that matters here. We have a keyed aircraft PMA switch with both Mag's as is standard on most factory production aircraft. Never have had one fail on anything we have had if it was a good make switch that was TSO'ed. We did learn a trick many years ago that we have adopted in our POHB and on any aircraft we fly set up with a standard key switch. We do a run-up then bring the power back down to an RPM just over idle, say 900-1,000. Then I turn the key to off for a spit second for three cycles. This checks the "P" leads for ground on both Mag's as the engine will stop firing on both sides if the grounds are working and helps clean the contacts in the switch just before flight. If the engine does not try to stop firing, we know to go back to the hangar tell we get it sorted-out. Hope this helps someone.
Yours, R.E.A. III # 80888

P.S. We also have a Key on the inside of some panel. I want tell you witch on the aircraft somewhere. That can be gotten at with a simple tool. Also a good idea on road trips to have a Hide-A-Key kind of deal, on board.
 
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... We do a run-up then bring the power back down to an RPM just over idle, say 900-1,000. Then I turn the key to off for a spit second for three cycles. This checks the "P" leads for ground on both Mag's as the engine will stop firing on both sides if the grounds are working and helps clean the contacts in the switch just before flight. If the engine does not try to stop firing, we know to go back to the hangar tell we get it sorted-out. ...

This was standard operating procedure at the 135 seaplane I operator I worked for.
 
RPM Limit Value

What do you mean "when the engine stops" What triggers the light? A rpm limit value? Or does it need to be at zero rpm to reactivate? How do you wire that it pick up zero rpm?

The engine doesn't need to be completely stopped to engage the starter, if it's windmilling at something less than the preset 600 RPM limit, the starter can be engaged.

The VPX includes a starter protection feature such that the voltage output to the starter switch is inhibited above 600 RPM. This feature makes it possible to have an easily accessible push button that needs no protection from inadvertent activation while the engine is running. I just wired the light on the starter button to show when the starter is enabled (under 600 RPM - light on) vs inhibited (over 600 RPM - light off).
 
I agree with the "keep it simple" doctrine as well, so I have three toggle switches side by side: Left, Right, and Start. Left and Right are ON-OFF toggles, Start is (ON)-OFF (ie. momentary ON). For safety I have one of the military-style red flip-covers on the Start switch, that I have to flip up in order to use the starter. Flipped down it holds the switch in the OFF position.

To protect from the "liability" issue people have, I suppose I could wire a second switch in-line to the Start switch but located out-of-sight on the sub-panel. I'd want to be sure that it was well clear of anything that might move in the cockpit during flight, as I wouldn't want it disengaged by accident and preventing an in-air re-start if needed. I haven't installed one of these yet.

When I bought the plane already flying, it had a Cessna-style keyswitch. I found I didn't like the keyfob swinging around in circles all the time while I was attitude testing.
 
I agree with Mell on this one. But it is what you like and want in your aircraft that matters here. We have a keyed aircraft PMA switch with both Mag's as is standard on most factory production aircraft. Never have had one fail on anything we have had if it was a good make switch that was TSO'ed. We did learn a trick many years ago that we have adopted in our POHB and on any aircraft we fly set up with a standard key switch. We do a run-up then bring the power back down to an RPM just over idle, say 900-1,000. Then I turn the key to off for a spit second for three cycles. This checks the "P" leads for ground on both Mag's as the engine will stop firing on both sides if the grounds are working and helps clean the contacts in the switch just before flight. If the engine does not try to stop firing, we know to go back to the hangar tell we get it sorted-out. Hope this helps someone.
Yours, R.E.A. III # 80888

P.S. We also have a Key on the inside of some panel. I want tell you witch on the aircraft somewhere. That can be gotten at with a simple tool. Also a good idea on road trips to have a Hide-A-Key kind of deal, on board.

In my past Warrior, the problem was not in the off position, it was that the switch was worn and would go PAST the off position to the left, and everything was HOT again even if you remove the key.
 
Key Switch

To take this a step further: I check key switches as described above but wiggle the key around while the engine is spooling down in the off position. If the switch is a little worn sometimes this will cause the ground to be lost and you can get a mag to fire. If this happens I consider it a failed test and would replace the switch. RV9 will have toggles and starter button.

Don Broussard
RV9 Rebuild in Progress
57 Pacer
 
Just to throw into the mix:

I have a keyswitch (industrial grade from McMaster) to enable the mag switches and starter pushbutton. Key out -> mags remain grounded and starter cannot engage. Key in -> mag toggle switches enabled, starter pushbutton enabled. (The pushbutton is DPDT and simultaneously grounds the right, non-impulse-coupled mag during start).

With the key out, no amount of button pushing or toggle switching will allow the starter to engage, and no amount of dumb-@ssery by kids or spectators messing with the prop will let it accidentally kick over with a hot mag.

Key goes in my pocket at shutdown *every time* for safety.

FWIW, I think a "hidden safety switch" is more likely to be forgotten at some point...out of sight, out of mind, as they say.
 
Just to throw into the mix:
With the key out, no amount of button pushing or toggle switching will allow the starter to engage, and no amount of dumb-@ssery by kids or spectators messing with the prop will let it accidentally kick over with a hot mag.
Key goes in my pocket at shutdown *every time* for safety.

But again since you normally kill the engine with the mixture, you still need to periodically "test" the off position of the switch. The typical "mag check" does not test the off position.
 
We did learn a trick many years ago that we have adopted in our POHB and on any aircraft we fly set up with a standard key switch. We do a run-up then bring the power back down to an RPM just over idle, say 900-1,000. Then I turn the key to off for a spit second for three cycles.

Curious...wouldn't that cause a back/after-fire?
 
Curious...wouldn't that cause a back/after-fire?
One flying school I attended did that as SOP at shutdown. Never had a problem the 7 or 8 times I did it with their planes. If it was such a risky thing to do, I wouldn't think it would stay as a SOP. YMMV.
 
But again since you normally kill the engine with the mixture, you still need to periodically "test" the off position of the switch. The typical "mag check" does not test the off position.

Edited: There are two hazards to verify against...inadvertant starter engagement, and "hand-prop" accidental starting. For the first, two tests suffice...the starter button is lit by the same power circuit that comes from the keyswitch to the starter so it won't be lit if the key is off, AND it's easy enough to press the start button and witness no starter engaged. For the second, the only mag that matters is the impulse-coupled left mag. This is actually *dual* fault tolerant with the keyswitch...the keyswitch would have to fail ON (open the circuit to the mag), AND the mag rocker would have to fail ON (same) on the shield (return to mag ground) side.

Neither would fail-safe a broken p-lead on the conductor (mag to rocker switch) side, granted, but that's true of all cases I know of.
 
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If I owned a 40 year old multi thousand hour plane then I would worry about a worn out key switch. My plane that will serve me the remainder of my flying career without needing an engine overhaul so a key switch should suffice. YMMV
 
If I owned a 40 year old multi thousand hour plane then I would worry about a worn out key switch. My plane that will serve me the remainder of my flying career without needing an engine overhaul so a key switch should suffice. YMMV

Don't be lulled not a false sense of security. Age isn't necessarily the fail factor of switches. I've seen fairly new switches fail too. Bottom line is that if you have a key type switch, you should check the "off" position periodically.
 
BTW I have had some issues with the key switch in my Warrior and because of those, I plan with my RV-10 to do something like Paddy describes, above. Although until reading his posts, I hadn?t considered using the VP-X to disable the starting circuit at some threshold engine speed.
 
My RV4, with a brand new key switch caused intermittent backfires on startup. This would shear a pin in the lycoming starter.
I happened a few times before I changed switches and I carried a spar shear pin, which was a half moon key, in my tool kit.

One time I was giving my young niece a ride from her place to our farm for a vacation. The anxious parents were standing clear and waving good bye to their child on her first flight. As luck would have it on start up it backfired and sheared the pin. I got out my tool kit, removed the cowlings, and fixed the starter. It took about 45 minutes. During that time I was sure that my brother and sister in-law were having second thoughts about this homebuilt aircraft!

I replaced that switch with toggles and did not use key switches on the eleven planes that followed it.
I have never had a problem with the toggle switched whether mags or electronic. I do a mag check at run up and always to a check at shutdown to confirm mags off.
 
This is a standard check that needs to be done to satisfy at least one AD on keyswitch ignitions in many aircraft...
http://rgl.faa.gov/Regulatory_and_G...C14960A415D956BD86256E520053A53E?OpenDocument

Indeed. However, the AD does not direct returning to "BOTH" after going to "OFF".

We do a run-up then bring the power back down to an RPM just over idle, say 900-1,000. Then I turn the key to off for a spit second for three cycles.

It's that part that seems like it might cause a after/back-fire. Would there not be unignited fuel in the cylinders and also down the exhaust? When switching back to "BOTH", seems like all that fuel is ready to ignite.
 
A mag grounding Check is imperative. There was a recent fatality from a hot mag in a 182. I have found a broken P-lead twice in the past decade by doing a grounding check. I do it at shutdown, mags off at idle and then on. Then advance to 1200 or so and pull the mixture. I also never leave the key in the ignition. Lastly, all guns are loaded and all mags are hot. They should be handled the same way for the same reason.
 
Shut down with mag switches instead of mixture?

Because my Fokker D.VII wannabe doesn't have a mixture control, every shutdown is a check of the mag toggle switches/p-leads. I've wondered why I don't shut down the O-320 in the RV-6 the same way.........
 
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