captinjohn

I was reading a good thread about kill switches. A lot more RC fans are getting into Gas powered airplanes. Please get a thread going and please do not close it just because someone does not agree. Most people read right over the arguing....but I feel it is a very important subject. I like RC Pilots way of having the throttle shut engine off and to also have another servo to choke it killing engine. It is good to have what you are naturally do... to kill engine...looking for a kill switch is not soon enough some times. So I say set the kill for your engine in the most natural way. I would say Idle trim is a habit for most. But add a choke or optical kill too if you can use it fast enough. Thanks Capt,n

Jake Ruddy

My Feedback: (40)

I don't really agree with what you are saying about being fast enough. Most people fly with at least one rate switch, many like myself use 3 seperate switches. It should be second nature to flip these switches and your kill switch or dial just like turning on your windshield wipers or turning up the radio in your car.

captinjohn

Jake...you mentioned "like switching your car wipers on" did you ever get in another car and try to find the wiper and since they was in a different spot....it took more time to find the control you wanted. Is there anything that you agree with what in what I said? Why cannot people take any of the good ideas in any post and just use them if they want? The bottom line I tried to get across was use what feels natural to kill the engine. I am not saying what anyone needs to do. I am not going to get in threads either to find something to disagree about. In fact I t bet my bottom dollar...you will never see a thread that I have disagree-ed with some person. It is just common courtesy. Capt,n

BarracudaHockey

My Feedback: (11)

If you're saying to use the idle trim to kill the engine, I disagree, you should have something separate. I dont think a choke servo work 100 percent of the time if the engine fires by accident or the plane gets away if its cold it can still keep running so I prefer an optical kill.

To each his own.

AA5BY

I agree with Capt,n... the idle trim kill is what has been working very well for glow fuel and I do the same on three gassers I own. I do understand that with gassers it is usual to use plastic linkage and suffer a slight temperature variant trim issue with the throttle that can be annoying to the engine idle and thus are tempted to use the carb idle screw for low idle. I've experienced this but don't find it impossible to overcome.

On the other hand, a recent thread about who uses rate switches indicated many have abandoned rate switches for exponential mostly on the grounds that they no longer have to deal with looking for or feeling for a switch on the transmitter.

Having said that, the throttle trim is not much different than any other switch or knob on the transmitter so if there is another switch that seems convenient... and no matter how it is rigged... it becomes a choice of what works for the individual.

We still have one mode-1 flier and our field and he is an excellent pilot much better than I. Would it be ok for me to tell him he ought to conform? He'd counter with the argument that mode-1 provides better precision control because of less interaction of pitch and roll controls and I'd have to agree with him and then change to mode-1. Think about it.

Rodney

To me it makes a big difference in what transmitter I'm using. If it has the mechanical slide trim switches, I prefer the low trim/low throttle be set for cutoff. If digital trim, I prefer a separate button (kill button) type switch where, when you press it, it moves the throttle that extra bit to completely close the carb to kill the engine. When using an electronic ignition, I prefer a separate servo actuated switch which removes the electronic ignition power . An optical switch works well there also. Each individual needs to use whatever method he feels comfortable with.

Tired Old Man

My Feedback: (1)

I don't think Jake rents many cars, or at least different ones. If he did he would understand just how exasperating changing vehicles and switch/knob locations can be. Personally I find nothing at all intuitive between JR-Hitec-Futaba-and Airtronics radios once an owner has made their personal switch assignments. Just like I don't find all that many similarities between Saab-Ford-Chrysler-and GM when it comes to panel and switch layouts. It gets worse when it comes to sound systems and heat/ac control functions.

So I fully concur with the Captain in this. I'm steering clear of the engine kill subject.

Jake Ruddy

My Feedback: (40)

Well I am sorry you guys couldn't relate to my example. I was talking about your own radio and your own car IE. "Your car". I didn't think my example was that hard to grasp.

I fly tons of people's planes and always go over where all the switches are for rates and kills, gears, whatever is on the radio. If you are unable to remember where it is on someone else's radio then maybe you shouldn't fly other people's planes. As for your own radio I would think you would choose a spot suitable for yourself.

Sorry I disagreed with you CJ, I didn't think it was that big of deal. I don't think trim is enough, it doesnt help with a servo failure, or a loose muffler which makes the idle go often too high for trim to kill. The other advantage if you have a radio problem it kills the engine.

BY all means use what you like but I think it's smart to have a choke servo or optical kill.

Tired Old Man

My Feedback: (1)

Perhaps a little on the judgemental side?

I'll walk away now to avoid having the thread cut off.

JustPlaneSweet

My setup is the throttle trim will kill the engine and a separate servo actuates a normally open micro switch in the electronic ignition power line. I use a manual choke. Part of my normal startup routine is to verify the operation of the servo kill switch.

Stan

captinjohn

In my first posting...I meant to say... by all means add a choke or optical switch...but make sure you practice using it to stop engine as quick as possible. If you cannot...you can chop up a few wings ect on other planes close by. I had a guy,s prop chop into my airplane. But it did not make us enimies....we actually flew together more. I had just met him when it happened!!!! Capt,n

Bashedit

My Feedback: (35)

It only took one time for me when the throttle linkage came loose. Had to fly the plane until the gas tank ran dry. Now I always have a kill switch. I have both the Smart fly and the 42% products type switches and they work well. Always shut down engine at the end of the flight with them and have them set to shut off if receiver goes into fail safe, don't want the plane to fly away to far.

larry@coyotenet

My Feedback: (21)

In my case it only took one time to have the kill switch go bad and cause me to lose a warbird when the engine died at the wrong time to stop using kill switches. It's six of one and half a dozen of another. I now set up my planes to die at low trim and normally use a kill button which is one of the functions on an Airtronic radio. Use whatever your comfortable with.

Larry

RTK

My Feedback: (1)

I just solved a problem with an intermittent optical kill switch I used for many flights. It actually introduce another failure point which did fail. I am not saying that a second means of killing an engine is bad, just that sometimes they induce problems and it can happen at the most inopportune time. On my larger planes I use a choke servo because it is easier to turn a knob than bend under a plane. I have lost a little faith in electronic kill devices.

liquid_TR

I really cant see the reason for an optical kill switch, apart from paying extra dollars for a useless and unnecessary prop..

Say you have a YS170 DZ glow engine on a 2m aerobatic model, swinging a 22x8 prop as hard as a 50cc gasser and vibrating just as much.

Does that one have an optical kill switch? A remote choke servo?? None!! Now shouldnt we use such a "dangerous" engine?
Should we manufacture a secondary system to shut the engine down by using a remote servo to pinch the fuel line? Its all none-sense to me..

Excuse me but in my not so humble opinion, optical kill switch is beyond you know what...
A remote choke servo can be handy if the cowling of the airplane is so tight that you cant run your finger in to pull or push a small rod to open or close the choke valve or you cant hook it up at all.. Thats about it.

If a throttle servo dies mid-air, its operator error 99% of the time.
If the throttle cable gets stuck, its operator error 100% of the time.
If the need for a optical kill fail-safe occurs with a depleted RX battery, its user error 99,999% of the time and the plane is trash in 30 seconds anyway.

jerdavis

My Feedback: (3)

Full scale airplanes have at least 2 ways and as many as 4 ways to power down an engine. Seems like a good idea to me.

Redundancy makes airplanes and people last longer.

A remote kill switch is easy to do on an ignition engine.

A remote kill is problematic for a glow engine. Most ways I can think of to kill a glow engine remotely (other than using the throttle) would be clumsy, bulky, and more likely to fail than the throttle. (It is tough to unscrew the glow plug remotely to interrupt the combustion process.)

Just a few thoughts.

JD

Tired Old Man

My Feedback: (1)

They have been using fuel cut offs in glow engines for decades but you don't see people running out in a panic to buy and use them like they are doing with gassers. It's not problematic at all, just that a glow engine is not perceived to be dangerous when for some reason a gas engine is. Their are far more propeller induced injuries with glow engines than gas. Seems with gas people think the sky is falling where with glow all is well and good.

So which is more dangerous, gas or glow? Realy think that through before comitting to an answer.

karolh

My guess is that some folks get swayed into thinking that an electronic remote kill switch is necessary because of the large size of most gassers.

Karol

Waynesworld

I put a 42% products kill switch on my 50cc gas engine. Flew the plane 5 or 6 times now and the last time i took it out the kill switch took a crap on me..glad i wasnt in the air..i fired the plane up and it just popped,dead, i have smart fly kill switch in my other 50cc plane and it has been trouble free, guess it wasnt worth saving $10.oo to get a cheaper switch

Jake Ruddy

My Feedback: (40)

I have seen so many problems with the non smart-fly ignition kill products its crazy, I dont know why people try and save the money without doing some reading.

RTK

My Feedback: (1)

Any time you put in more failure points you are bound to have more failures. Think about one of those big electrics, they are always ready to bit you. I would be much more careful with them than a gas engine sitting there not running.

Called up the company which optical kill switch I had bought and they are sending me a new one. The man on the other end of the phone was very nice and helpful, great customer service Quest, and yes I will be putting it back on with a little different wire hold down method.

Jake Ruddy

My Feedback: (40)

I tend to use extra sticky doublesided tape and have good luck. Include a drop of medium CA on the wood side from time and it seems to hold up. I use that for my satellite receivers as well.

karolh

I have a RCATS RC100 electronic switch fitted in one of my gas models which was installed more out of curiosity than anything else, and although it's proven to be very reliable and convenient to use I am not convinced that it has to be a standard item in ALL my models.

Karol

liquid_TR

You are missing the point.. these are not full scale planes.. the components arent upto 1:1 scale plane standards.. they are cheap and failure prone.

Redundancy components in these small RC planes usually present more failure points.. same story with completely unnecessary power expanders on 50-60cc class airframes..

I would rather spend my money making the model lighter with carbon fibre..

OldRookie

My Feedback: (13)

Well...in the first place the YS 170 DZ doesn't have an electronic ignition system, so the need doesn't even apply. Really bad analogy.
The YS 170 DZ also doesn't have a choke, so the need of a choke servo isn't necessary either. This is also a really bad analogy.

You know what they say about opinions and a**holes. Everyone has one, and they all stink.
Do what ever YOU like the best and let other people decide for themselves, without your attitude.

Greg