I just traded my Trex 600N for an EF yak 54 with a DA50. It came with a smart fly otic kill. I'm trying to loose weight by running one Li-po. Is it safe to Y three lines from the lipo....two to the Rx and one to the smart fly?

if your on 2.4 I would say yes.i run a single 2300 a123 to RX and ignition with two power leads off it.
good luck with the diet I couldn't get mine under 18lbs. with a single a123.and there wasn't nothing in the plane that wasn't needed to fly the plane.no spinner.wheel pants,igntion kill,it was basic glow engine set up.
one other thing will have to drop your voltage down to 6 volts max for the ignition.

I would suggest you get an IBEC with some noise filtering from the ignition to receiver. Tech-Aero IBEC works well as an ignition kill as well as supplying regulated voltage to the ignition and do not require a mechanical switch. It is turned on when you switch on a channel.

1 battery, 2 leads on all my 50cc stuff, no issues, you don't need an IBEC but they make a convenient ignition kill but if you already have the smart fly just run it like that.

You must regulate that voltage though. I would get an IBEC for safety too. Without it, you have no way of switching the ignition unless you are touching the plane.

What part of "it came with a Smart Fly optical kill" didn't you read in the first post?

myself I don't use any type of IBEC, or ignition cut off.it's just one more gadget to eliminate when you start having trouble with engine missing,not starting.nothing wrong with just a simple throttle cut,it has work for me for 15 years with out any problems.
I know all you worry warts are going to pile on top of this.

Originally Posted by closetguy

myself I don't use any type of IBEC, or ignition cut off.it's just one more gadget to eliminate when you start having trouble with engine missing,not starting.nothing wrong with just a simple throttle cut,it has work for me for 15 years with out any problems.
I know all you worry warts are going to pile on top of this.

To each their own of course and many run without a kill switch but I've had and seen my fair share of throttle servo failures. Most were at idle on a near full tank of gas. What would your throttle cut do in that situation? Fly around for an hour or more hoping you had enough receiver batt left? What if the throttle was jammed in some way causing a major drain on your batteries? Without a remote kill switch you'd be SOL.

Sure - an optikill can go bad or cause engine trouble but that's not inherent to the device itself. They can fail just like servos and everything else can but with a big difference of having no moving parts so the reliability in theory should be higher. The situation can become much worse if you lose control of your plane in a WOT situation. An optikill can be set to switch off the igniton in failsafe mode.

No issues in 15 years is like a smoker saying they haven't gotten cancer in 15 years of smoking so it's OK for them to keep smoking. Just my 2 cents - I simply choose not to play russian roulette with my planes.

Ah, the well seasoned veteran has spoken. If you don't do it the Cerus way, you are putting the world in jeopardy. Thanks for the grandfatherly advice!

Originally Posted by BarracudaHockey

What part of "it came with a Smart Fly optical kill" didn't you read in the first post?

What part of the "I want to reduce weight" don't you catch on to.
Ps, just busting your chops.

thanks guys..I wasn't sure so I put in a 1600nimh until the ibef arrives

Originally Posted by Cerus98

To each their own of course and many run without a kill switch but I've had and seen my fair share of throttle servo failures. Most were at idle on a near full tank of gas. What would your throttle cut do in that situation? Fly around for an hour or more hoping you had enough receiver batt left? What if the throttle was jammed in some way causing a major drain on your batteries? Without a remote kill switch you'd be SOL.

Sure - an optikill can go bad or cause engine trouble but that's not inherent to the device itself. They can fail just like servos and everything else can but with a big difference of having no moving parts so the reliability in theory should be higher. The situation can become much worse if you lose control of your plane in a WOT situation. An optikill can be set to switch off the igniton in failsafe mode.

No issues in 15 years is like a smoker saying they haven't gotten cancer in 15 years of smoking so it's OK for them to keep smoking. Just my 2 cents - I simply choose not to play russian roulette with my planes.

worry wart no. 1

the previous owner had installed two switches. I cut both female switch leeds and soldered them to a male deans...which connects to a Li-po. the male switch leeds Y into both aileron channels. I guess I'll find out tomorrow how many milliamp hours two flights takes out. What battery size do you guys use for a single hi-voltage battery setup. I have a 25C 2500mah, but a buddy has a bunch of 4000's he'll sell.

I personally like flying at the field, not charging. I'll scarifice 4 oz of battery weight to fly all day long!!

BTW- My Comp ARF MX2 uses 2 4000mAh Lipo on 8 Savox 2270's and JR 9411 on throttle. I can fly all day long on 8000mAh!! Well, all weekend!!

Originally Posted by Knobby

Ah, the well seasoned veteran has spoken. If you don't do it the Cerus way, you are putting the world in jeopardy. Thanks for the grandfatherly advice!

If you wanna take it that way that's certainly your choice - free country and all. I merely laid out my opinion and a few facts. I know many who don't run kills and many who do. Some know the risks but some don't either. This hobby is about continuous education and spread of knowledge. The potential for an engine to have issues due to a kill switch is a small price to pay for peace of mind.

Besides that - closet was expecting someone to say it - didn't wanna disappoint.

Originally Posted by Bunky F. Knuckle

I personally like flying at the field, not charging. I'll scarifice 4 oz of battery weight to fly all day long!!

BTW- My Comp ARF MX2 uses 2 4000mAh Lipo on 8 Savox 2270's and JR 9411 on throttle. I can fly all day long on 8000mAh!! Well, all weekend!!

Amen to that. My 33% Hangar 9 Extra has redundant (x2) 2700 mAh 6v receiver packs and a 2500 mAh 4.8 ign pack. It's no 8000 mAh but its plenty to not have to worry about field charging.