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  #11  
Old 11-28-2014, 06:15 PM
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Sam Buchanan Sam Buchanan is online now
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Originally Posted by Toobuilder View Post
I thought long and hard about doing just that. In the end, I decided that I might just need to engage the starter in flight. The chances are so remote as to be incalculable, but I just can't get past that possibility.
Same here, my starter push button is wired through the master switch so inflight restart would be possible without having to remember what combination of switches have to be thrown to energize the starter.
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  #12  
Old 11-28-2014, 06:57 PM
Canadian_JOY Canadian_JOY is offline
 
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Something nobody has mentioned yet is the mechanical aspect of the switch installation. If you're note careful, this will bite you!

Normally we install toggle switches so when the toggle is "UP" in the "ON" position, the switch contacts are closed. Mag switches are exactly the opposite. "UP" actually is the "open circuit" position.

A good general guideline is the small hole we use for the anti-rotation washer on the switch is normally below the big hole for the switch toggle. For mag switches, the holes for the anti-torque washers are above the switch toggle.
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  #13  
Old 11-28-2014, 07:15 PM
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Quote:
Originally Posted by Toobuilder View Post
I thought long and hard about doing just that. In the end, I decided that I might just need to engage the starter in flight. The chances are so remote as to be incalculable, but I just can't get past that possibility.
My feeling on that is if you loose the engine during flight caused by fuel starvation, etc., the prop will continue to windmill. If the prop stops, you have other problems and probably don't want to use the starter anyway. Absolute worse case, you could always turn the avionics off to do a restart, but I can't imagine what circumstances would cause this scenario. YMMV.
Bottom line; Everyone needs to do whatever they are comfortable with.
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  #14  
Old 11-28-2014, 07:45 PM
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Quote:
Originally Posted by Canadian_JOY View Post
Something nobody has mentioned yet is the mechanical aspect of the switch installation. If you're note careful, this will bite you!

Normally we install toggle switches so when the toggle is "UP" in the "ON" position, the switch contacts are closed. Mag switches are exactly the opposite. "UP" actually is the "open circuit" position.

A good general guideline is the small hole we use for the anti-rotation washer on the switch is normally below the big hole for the switch toggle. For mag switches, the holes for the anti-torque washers are above the switch toggle.
You are correct...and it was inferred with bold font in post #4.

But it never hurts to reinforce this info because switches installed incorrectly could be deadly.
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  #15  
Old 11-28-2014, 07:56 PM
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AeroElectric Bob's latest Z-11 schematic shows toggle switches and includes the "start on Left mag" interlock.

http://www.aeroelectric.com/PPS/Adob..._Pdfs/Z11N.pdf
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  #16  
Old 11-28-2014, 07:57 PM
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Quote:
Originally Posted by Mel View Post
My feeling on that is if you loose the engine during flight caused by fuel starvation, etc., the prop will continue to windmill. If the prop stops, you have other problems and probably don't want to use the starter anyway. Absolute worse case, you could always turn the avionics off to do a restart, but I can't imagine what circumstances would cause this scenario. YMMV.
Bottom line; Everyone needs to do whatever they are comfortable with.
Mel, when I bought my -7 it came with a wood prop which made me think of what would happen if I lost my engine due to a stupid pilot mistake like running out fuel. In cruise flight at high speeds I would simply switch tanks with the prop turning (hopefully the other tank has fuel ), but seriously, if for some reason the same thing happens in the pattern and I'm within flap speed the wood prop does not have enough inertia to continue spinning, requiring a quick switch of the tank and a restart with the starter. I even tested it at altitude and once the wood prop stops spinning at low speeds it requires a drastic dive to over 120knots to get it to start the engine on its own . . . obviously not possible at pattern altitude. I know most people don't have wood props but it is something to think about.
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  #17  
Old 11-28-2014, 09:55 PM
jbDC9 jbDC9 is offline
 
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Quote:
Originally Posted by Bill_H View Post
You might consider using a keyed switch for the starter rather than a push button for safety reasons. Or in the fuel circuit or something. The RV12 has 2 switches for the dual ignitions and a keyed starter.
Huh? How is a keyed switch "safer" than a push button for the starter?

Quote:
Originally Posted by vic syracuse View Post
Here's a trick I use when using toggle switches, especially since Rotax recommends not using the standard key switches. I wire the 12 volts to the starter switch through the Strobe light switch. That way the strobes are on for starting and it takes both the master switch and the strobes on for the starter to be hot. Adds a little level of security and safety.
Again, huh? How does wiring a starter thru the strobes add security and safety? All I see from that scenario is annoyance from other pilots on the ground being blinded by your strobes.

I've had 2 mag toggle switches and a push button starter on my RV-8 for 1100+ hrs, three stone simple circuits with no safety issues... what am I missing? I don't mean to stir the pot, but these two posts make absolutely no sense to me unless it's some funky RV-12/Rotax thing. BTW, the original poster looks like he has an RV-8A.
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  #18  
Old 11-28-2014, 10:15 PM
sblack sblack is offline
 
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I guess the implication is that it is easier to accidentally engage a push button than a key switch. One could always use a momentary toggle with a cover.
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  #19  
Old 11-29-2014, 06:22 AM
vic syracuse vic syracuse is offline
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Quote:
Originally Posted by jbDC9 View Post
Huh? How is a keyed switch "safer" than a push button for the starter?



Again, huh? How does wiring a starter thru the strobes add security and safety? All I see from that scenario is annoyance from other pilots on the ground being blinded by your strobes.

I've had 2 mag toggle switches and a push button starter on my RV-8 for 1100+ hrs, three stone simple circuits with no safety issues... what am I missing? I don't mean to stir the pot, but these two posts make absolutely no sense to me unless it's some funky RV-12/Rotax thing. BTW, the original poster looks like he has an RV-8A.

This is why I even hesitate to try to help any more on this site. There always seems to be a smart answer. All you see is annoyance to other pilots from being blinded by your strobes??? Give me a break. Most checklists actually recommend that the anti-collision lights be on for safety prior to starting. On busy General Aviation ramps with a mix of corporate and GA traffic where there are lots of loading/unloading of passengers and ramp crew around, I find it imperative to get the strobes on, look around and yell very loudly. Yes it is a safety factor. Strobes on do tend to get everyone' attention. If it's at night I pay attention and delay a start so as to not inconvenience someone, and I will in fact turn the strobes off after start and leave the Nav lights on if it is distracting.

As for security, many years ago I had a friend who lost his homebuilt on a ramp at a fly in due to a drunk bystander getting in and starting it up and almost killing people before the aircraft came to a stop. So it's always been on my mind and I try to add a second level of security to the START function.

As for the engines windmilling, it's true for our typical fixed pitch and even constant speed propellers without a feathering function. But not so with the Rotax. They WILL come to a complete stop in flight if there is fuel starvation, and do require starter engagement to get going again. I test this function on every Rotax-equipped airplane I test fly.
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  #20  
Old 11-29-2014, 06:41 AM
94kb 94kb is offline
 
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Default start lockout

I hadn't thought about a drunk but I am concerned about kids. They will flip every switch and push every button. I put a SPST switch behind the panel which is in series with the start button. It is easy to reach and only I know where it is.
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