Smart Fly Optical Kill Switch

[storklappe]

Today I started up my new DA-100 in my new airplane for the first time. The new engine started after several flips. It started at full throttle (the stick was at low throttle).

My Dad was holding the plane by standing in front of the stab. He couldn't reach down and hit the ignition battery switch on the side of the plane and I couldn't quickly get to the switch since I was in front of the prop.

Fortunately, it was a non event because my Dad just hit the Smart Fly optical kill switch on the transmitter.

Although I checked everything over several times before running the engine,I still screwed up because I missed the throttle servo being reversed. With it reversed the throttle cut function wouldn't have any effect.

I am sure glad that I put in the Smart Fly system. I didn't think that I could make a bone head mistake like having the servo reversed.

[3DBatixkid]

Pretty sweet to have the kill in there. Buddy of mine started his plane without the transmitter on. Dont know how it got to half throttle, but it took off, did a 180, and took out the left wing of a beautiful carden behind him. He ordered a kill right after that.

[All Thumbs]

Yeah... I'm with Zack. I'll never run an airplane without an optical kill. The other real benefit is you cannot start the motor without the receiver power turned on.

[Mark Davis]

I use the Smart-Fly kill switches on all my gassers... I like the idea of being able to kill the ign from the Tx... That is until the day I let a buddy fly one of my planes... He flipped a switch which he thought was smoke... You guessed it, he killed the engine while doing rollers at 100 AGL...

I bet you check servo throws & directions next time you start the engine on a new plane...

[Mark Davis]

Duplicate post...

[DKjens]

If you're ever in doubt and you can't visually inspect the operation of the carburetor, flipping the engine with ignition off will sound very different with open and with closed throttle.

[Dan J]

I think your crazy not to have an ignition kill on a gas plane. It's so much safer.

[MattyMatt]

I agree as well... this should be a manditory saftey item. It is in my planes. Lets face it, it isn't expensive.

For those that think it is, the first time you have to replace a prop because you ran off the run way on a windy day and had a prop strike... you could have cut the engine and it just paid for itself. This happed to my buddy the first flight... he saved it because he put the optical kill in.

[rcplane]

Great piece of mind, knowing you can shut it off like that.
We all have seen the guy with the throttle servo disconnected, flying forever waiting for the plane to run out of gas.
One time a guy here had plastic pushrod for the throttle and it melted. The throttle was so low it would hardly fly but to high to land, it went on forever, until..... it melted a bit more and crashed. Bummer.
Smart fly forever!

[Kiwi]

I agree 100% they should be mandatory, fail safe only works if the linkage is intact so in my humble opinion its pretty much worthless unless you can kill the spark.

On a funnier note have you ever seen a guy loose the servo and have it jam on full throttle. You know you cant do much more than go up when that happens so when your tanks full your really in a pinch. You cant keep going up so you must come down, but on full power. There is not much you can do except pray that you dont rip the wings off.

Most times the plane ends up shredded. Next time your out try parking the throttle at full power and fly for a minute. Its a near impossible act to do something to keep your plane intact, under control and in a position that when it does run out of gas your going to get it back.

Electronic engine ignition kill systems should be mandatory on gas planes.

Kiwi

[DKjens]

Kiwi, my man, with a throttle stuck open, you just do a million waterfalls, he he.

I also try to promote the SF Optical Kill Switch to anybody with a gas engine just for those reasons, it's independent of the receiver and fail safe setting, it will not let the engine start and it will shut it down if loosing power.

[ronfurious]

Could'nt you add a program mix to the cut off sw that the throttle stick must be below about 1/4 throttle to enable the cutoff switch. Even if the linkage or servo malfunctions the > 1/4 throttle signal "mix" would prevent inadvertant activation of the cutoff switch while retaining all the benifits of it.

[sweetpea]

Sure you can do all that......but

There have times when I need to kill the engine now! Taking the battery out of the loop is the fastest way to do it! I use both smart-fly and Electro Dynamics optical kills.

Also all that mixing means absolutely nothing when your throttle servo fails, gets hung-up or you have some other problem that needs the engine killed.

[bosshoss]

A friend lost a Carden when his thrott servo jammed at just over idle , too fast to land. 32 oz tank, not enough battery....just when he was thinking of greasing it in and nosing over to kill it, it quit....the batteries quit. totaled.

I will never fly a gasser without a remote kill independent of the throttle. SF Opti-kill or even a old-school servo and switch.

[catman3070]

	Quote: Originally Posted by sweetpea
	Sure you can do all that......but There have times when I need to kill the engine now! Taking the battery out of the loop is the fastest way to do it! I use both smart-fly and Electro Dynamics optical kills. Also all that mixing means absolutely nothing when your throttle servo fails, gets hung-up or you have some other problem that needs the engine killed.

This is absolutely correct. I never used to run kill switches until I had a throttle servo jam at just under half with a full tank. Longest 25 minutes I have ever flown. Looking on the positive I can almost do a rolling circle with my eyes closed now.