RichieN

My Feedback: (5)

I’ve been using kill switches on all my gassers after the same thing of servo tray coming loose happen to me. I’ve been using Rcexl and 42% and I’ve never had problem with any of them and so far I only see benefits of using them.
Few years ago I’ve lost the plane to receiver battery in flight failure. It’s not about loosing the plane, it’s about this helpless filling watching the plane gliding by it self. Since then I’m using dual battery and battery share on almost all of my planes-small glow stuff is excluded. This is just a peace of mind that makes this hobby more enjoyable for me. If it’s not mandatory it’s up to user preference.

warbird72

My Feedback: (79)

Metallica rules!!

MetallicaJunkie

indeed they....especially the old stuff im not a fan of Load or Reload and definitely not of St Anger.... Death Magnetic was ok

back on track before the mods get angry [8D]

i didnt realize this topic was gonna creat a pot to be stirred

stevenmax50

My Feedback: (1)

Cool

a1pcfixer

My Feedback: (7)

Yeah, uh-huh. sure.
Go back & read Post #3 again. (I told ya so)

willig10

T.O.M. Really? fear mongering? Uh to use your past comments about looking up things prior to asking May I refer you to the club rules that a lot of us are members of. This club is called the AMA and before I go there let me say a couple of things.

Can a gasser be flown safely without a optical kill switch or onboard servo operated choke? You betcha. Is it the right thing to do? I'll get to that in a moment.

I too fly full scale and you are correct we cut fuel to the engine. This option is not available to us as RC pilots. On a full scale carburated engine we have at our convenience 4 knobs in order they are:
1. Primer
2.Throttle
3.Choke
4. Mixture.

These are not available by means of using a transmitter on our RC aircraft while in flight. You can choke an engine to make it die but you are not gonna be able to cut the fuel until someone comes up with an inflight mixture control. If you have a vendor or part # please let us have it. Until then we really have4 options in flight available to control our RC engines:
1. Throttle
2. Choke
3. Trim switch
4. An onboard kill switch.

Now I will say this. I have and still do use only trim to kill my gassers on less than Giant scale aircraft. However I will never try to instill fear on anyone who wants to be safe. Safety should always be the main thing and trump any other activity. Can an RC gas engine be safe without an onboard kill switch? Yes.

Now let me expound on fuel consumption on a glow engine vs. a gas engine at the same throttle setting and the same amount of fuel in the same size tank. A 2 stroke glow engine will burn through a fuel tank rather quickly compared to a gasser. You all know this to be true. So If glow engine throttle sticks it is gonna dead stick long before the gasser does. I think we are all agreed on this.

Now to the meat of the matter. As per the club we belong to called the AMA if you go to the "Giant Scale" rules there is some verbage there that speaks specifically to this subject and I quote:

Rule 5: All engines must be able to be shut off from the transmitter by either a servo operated kill switch or by closing the carburator. All aircraft with ignition engines must have a manual emergency ignition kill switch visibly mounted on the exterior of the aircraft. Now bear in mind this rule is for a contest and is the minimum requirement.

As stated previously (and to all I am not fear mongering you into anything) it is your decision to use a choke, trim setting, onboard kill switch or whatever means you decide to be comfortable with. I choose to go the way I go as it is conveninet, light weight, inexpensive and it works.

I would love to have a "REAL" fuel cutoff switch for my gassers but have not come across any and if you guys know of any please give us a link on where we can purchase them. I can see maybe a Sullivan smoke pump working as a real fuel cutoff switch but they are around 100.00 or so.

Anyway not beating anyone up for trying to be safe. Good on you for doing so.

Regards
Glenn Williams

aussiesteve

Hello, My name is Steve and I fly full scale too

In my full scale planes (PA32R, EA300LP, DH87, AT504) I don't have a radio link affecting control surfaces, nor do I have amateurs working to build, maintain or fly them. (and how do you use the primer to shut the engine down anyway?) Enough said about that.

In many of my models (not all of them), I have Optokills. The reason for this is that it is effectively impossible to attend a fly-in or an IMAC meet here with a gasser without meeting the "Two methods of shutting the model off, one of which may be the throttle stick" rule. The actual rule doesn't say they need to be from the radio but it is usually construed as such and politically it is easier to just go with the flow and install an Optokill. I use the best one I can get (which is the SmartFly) and have never had an issue with that particular product.

On a couple of my smaller planes (less than 50cc), I use an IBEC to eliminate one battery and save weight and installation room. (T.O.M. - this is something we will agree to disagree on ). An added benefit of that unit is it incorporates the same features as an optokill so those planes have the same function by default.

My planes that have Choke servos have them because of the choke setup on the enigne making it more difficult to use a manual choke.

For the record, I agree entirely with T.O.M about the amount of fear mongering that goes on. Not so long ago there were plenty of 2.4 and even larger glow engines being used that had more power than many of the 30cc (2.4) gassers have now, there was never an "alternative to the throttle close-off" issue with those was there?

Don't get me started on why I have Canisters on a couple of my planes or why I changed fields a few years back because the old club ruled gassers out because they had a higher fire danger because of the ignition system

DISCUS54

My Feedback: (211)

Oh yea...misinformation and fear mongering to effect and end.... that's never been done before.[X(] I'll keep my opto switches. BTW, we use to have a lot of "Barneys" out here giving some of the guys a hard time, but most have moved on...to the TSA. Now think about it...where would you rather have them. Life is about matching talent with task.

OliverJacob

My Feedback: (12)

I fly full scale as well. We shut the engine down by leaning the mixture. And that is for safety. Since our older planes have a carburetor and dual magnetos, someone could accidentally start the engine by moving the prop in case we have a bad ignition switch or ground wire.
The choke rather floods the engine, which probably make it easier to restart, but it's not as safe.
I use an optical kill switch as safety. So should I leave the ignition on and someone decides to flip the prop, the engine won't start unless the tx and rx are left on, too. Which is unlikely. If you have kids in the house, you know what I am talking about.
There is no absolute safety but the $15 for the kill switch is money well spend.

my 2 cents

Speedy-Gonzales

My Feedback: (202)

I use the 42% "Zeus" that has worked flawlessly on my ZDZ 60. It is a kill switch, a voltage regulator, and it emables you to use your Rx battery for ignition module. You gotta compensate with a bigger battery(s) but it is a nice setup.

http://www.valleyviewrc.com/Zeus%20f...20Products.htm

Speedy

Upnet

My Feedback: (8)

As part of my ongoing "gasser" education....I assume a throttle stop prevents closing the throttle beyond where the stop screw is adjusted. So if you remove the screw...the carb can be totally closed with the stick...then further closed with the trim on the TX. Have I got that right?

7. Remove and toss the "stop screw" on the throttle arm plate, then unhook the little spring that pulls the butterfly closed, unless you want your throttle servo under constant load/tension. Do NOT REMOVE THE SPRING.

willig10

Upnet:
Not sure where you are in the gas engine side of the house and I am sure you are going to get a lot of opinions. Here is what I do to all New engines that I purchase that have Walboro carbs.

1. The setscrew gets removed entirely. (the one that holds the butterfly partially open for idle). I adjust the butterfly with my servo setup.
2. The return spring. Do not remove it but pull the spring tab away from thethrottle arm and let it drop under the arm. This will allow the throttle plate to move freely and the spring is now under the armand keeps the butterfly plate centered inside the opening for the carb.
3. The choke plate has a spring and ball that makes a positive lock. If you are going to use a servo to actuate the choke, remove the carb and then remove the spring and ball. Re-assemble and when you attach your servo and ball link you can adjust the throw with your transmitter to achieve full closure and full opening.

All that said. Some guys do not do any of the above. I do not like having any force fight on my throttle servos as it uses battery power to overcome and is hard on standard servos. I am currently out of town on business or I would have posted some pictures of the spring and throttle stop removed.

It is your decision to use a setup that you are comfortable with. I hope this helps you somewhat.

Regards
Glenn Williams

Upnet

My Feedback: (8)

I have one gas plane...yet to fly. I have been looking at the "sticky" . To set it up correctly. Thanks for your reply.

cloudancer03

My Feedback: (22)

oh boy do you like stirring a b ee hive!as someone here said you'll get answers from every angle and in the end its still up to u to decide.personally I like killing the throttle from transmitter.I have been doing that with all my glow planes and its very reasonable from a safety standpoint.

aussiesteve

Hi Upnet
Cloudancer & Willig are right, there are a number of opinions on the answers to your questions.
Here are mine from my experience

Throttle Stop Screw
Remove it and cut off the mount for it (not the entire mount though as part of the mount sometimes acts as a stop point for full open - take a close look and see).

Throttle Servo adjustment
Once the throttle plate has fully closed, it can not be closed any further. I set mine so that the throttle plate is fully closed wiht the throttle stick fully down and the throttle trim about 2 or 3 clicks open from the lowest setting. I also set the throttle open to be about 1% (on the End point adjustment) off the full throttle open point, this is to preserve the throttle servo form bottoming out and that last little bit of the throttle travel serves no practical purpose for us on any of our engines.

Throttle linkage. Add an extension on the throttle arm so that you use as close as possible to 100% of the throttle travel to move the throttle from fuly closed to fully open. There is also a set of pictures somewhere that Jody made up that shows how to get the most out of a throttle linkage (I don't have them here)

Throttle return spring.
Don't remove the spring entirely as it acts as a spacer on the throttle shaft. If you decide to use a different arm for the throttle arm (Some use Steering arms etc) put a similar spacer in its place (Some use silicone tubing, others use a cut down spring, some use a brass or aluminium tube as a spacer).
There is no practical need to disconnect the spring from the arm but there are a couple of practical reasons to leave it connected to return the throttle. 1 is to help the throttle return in the case of misfortune, the other is to remove any accelerated wear on the servo traiin from vibration. The amount of back pressure on the servo will cause no harm if you use a decent servo and it wil lnot drain your battery any faster.

Diablo-RCU

My Feedback: (1)

Do you folks use Optokill switches on your elevator or aileron servos? What are you going to do to prevent those servos from failing and crashing your plane? I use no kill switches at all because I like to keep things simple and avoid multiple points of failure. Be smart when you select your servos and the control linkage so they are unlikely to fail. Make sure your plane is glued together well enough so that the engine box won't fall off in flight.

Speedy-Gonzales

My Feedback: (202)

Being able to kill your gas engine with a remotely operated device is MANDATORY at any AMA or IMAA event. You can do as you wish on the "back 40" but otherwise it is required NOT an option. Also if your flying site is a AMA Chartered flying site it is required under the AMA safety guidelines. It is noted that the AMA guidelines are just as mentioned. They are guidelines but nonetheless should someone get hurt the buzzards will show up in short time. Even if I have mis-stated the remote kil guidelines it is just smart thinking to have some device in place.

On the other side of the fence is this:
We have a flyer in our club that was flying a Converse Indiana and they fly on hard surface there which limits the use of a plane restraint. The plane was being held by his spotter and when the plane fired it lurched forward and severed 3 of the pilots fingers in a split second. NO time to flip any kind of a switch to avoid tragedy. IN a startup situation would it be safe to say the person starting the engine should not have the transmitter. Much room for debate here I'm sure.

I am getting more off on to the subject of safety but the kill switch is a safety device. Having a kill switch will never make mishaps obsolete but I'm sure all will agree you should at least have something in place. Doesn't matter what brand or type as long as it works.

I would say that the ground is the most often used "kill switch" known in our hobby. Not the safest but the most used!![:@]

SPEEDY

J-3

RC-100FO Electronic Switch

a1pcfixer

My Feedback: (7)

Possibly the best posting so far in this thread has been....

Might do us a world of good to take a moment to step back
and view the bigger picture here.

Methods of remotely killing a gasser;
1) Throttle servo only (mechanical)
2) Choke servo (mechanical)
3) Ignition kill (electronic)
4) Micro switch + servo (for magneto setups)
5) Combination of above choices

Choosing one or a combination of those is far more important
than none -or- which is assumed to be best.

No single choice is immune to eventual failure.
No single choice is best for everyone.

Fear mongering can come from many sources. Possibly the worst
is from hobbyists who attempt to degrade & demean others who
don't follow their chosen method, and instead think for themselves
and select their own method of killing their engine. When fear &
intimidation are used to reinforce an opinion, they've instantly
lost all credibility to their argument.

There is NO perfect solution to this subject of remotely killing your
gasser, NONE! Each choice has it's pro's & con's. Except for a few
loose cannons, the majority here see the value of having several ways
to kill their gasser.

More important than WHICH choice we make, is that we HAVE a means of
remotely killing our engines.[sm=thumbup.gif]

Regarding the survey, I'd bet Robert Ritchey is happy![8D]

Tired Old Man

My Feedback: (1)

Read the IMAA rules again. Your first statement is wrong. The rules state you must have a secondary means of shutting off the engine. The rules were written in the days when a magneto was present. A manually activated switch on the outside of the plane meets the requirements since it was used to interrupt the circitry of the magneto. An idle trim throttle close meets the fisrt cut method requirement.

No remotely operated kill is not now or ever been required in any of the AMA or special interest group regulations that are part of the AMA. IMAC and IMAA are two of those special interest groups. What you mentioned in the quote is an often mentioned misinterpretation of the engine kill rules.

Tired Old Man

My Feedback: (1)

Willig,

A throttle return spring is a negligible force on a servo if the servo is sized correctly to begin with. Use an amp meter sometime to actually measure the current draw instead of trusting the statements of others that say the spring generates higher current draw from the battery.

If the spring was a current hog just think how bad the situation must be for people using digital servos on large flight surfaces. All the weight of those surfaces would have to be making the digital servos work harder to maintain neutral against the force of gravity. The reverse is more the case. Once a servo reaches its commanded position the current draw falls off to almost zero, even when using digitals on large fligth surfaces.

Facts beat tribal knowledge, and the use of accurate set up equipment and some experience develops knowledge generated from facts.

acerc

A while back I said I use them. But now after many, many flight's I have not found a need for it. In the beggining I was advised to use them so I did. Now between the throttle cut and choke I see no need. Just connect everything appropriately and there is no issue. If you did'nt have a problem killing your glow you won't have a problem killing your gas. If you did, thenyour not doing something right.
And I'm with T.O.M on the throttle spring. Leave it on.
IMHO!

Tired Old Man

My Feedback: (1)

My opinion below inside quote:

If one needs to have a survey result to determine what they should do in their hobby they have yet to learned enough about the activity they wish to participate in to make reasonable decisions and choices. They lack both experience and the ability to think for themselves

clivemc

new technology ( and this is not specific to opto kills before someone points out they are not new) is often met with negativity or secptiscm- i couldnt agree more. there is no right and no wrong, other than maybe one point. Do not use an opto kill as your sole means of cut off, engine setup is important. but to add an opto kill when your setup is already there - why not? i do and its a great added extra for me

no offence guys, but we all move forward with technology. just stop and think for a while, how many of your daily chores are now enhanced by electronic automation or devices. My opto kill is just that for me, its my first automated / flick of a switch engine kill device, but should it fail i have backup......... and for all those that say you can bump the switch by mistake and cut your engine, they should learn how to use their tx and switches more. heck if you cant operate a switch how often do you push down instead of pull up ????

Tired Old Man

My Feedback: (1)

Although I'm certain the comments about the use of new technology were not directed at me, consider; what flight systems use the latest advanced technology to provide the greatest relibility and accuracy of flight in aviation? The answer is unmanned aviation and passenger carriage commercial aviation. I work in one of those fields so one should be reasonably assured that the technology I work with is quite a bit more advanced than what modelers have available to them.

There is nothing even remotely advanced in technology where remote engine cut offs are concerned. Unless one considers the 1980's advanced.