Stopping a helicopter

The heli guys I hang with just rest the palm of their hand on top of the rotor head and the blades slow to a stop.

Personally, I would set the idle trim to stop the engine.

Yes. Otherwise people will be alternating between laughing their asses off and rushing you to the ER.

If you have a programmable transmitter, set your throttle end points to "It's Dead, Jim" and max rpm, add a throttle-hold mix switch to set throttle position to idle. Now you have a useful throttle range, plus a kill switch...

The way I set 'em up is with throttle trim to high, the engine will run. Throttle trim to the low setting kills the engine. (assuming the left stick is full back)

I see you've also posted this question in other newsgroups. With all due respect , set the heli aside for awhile and get some experienced help before 'playing' with it again. If you don't know how to stop the engine , you are exposing yourself and especially those around you to the possibility of some very serious injury and you really shouldn't be messing with it. These can be very dangerous machines so please read all you can , and , above all , some expereinced help before you even start it.

KD.

"The OTHER Kevin in San Diego" wrote in message news: snipped-for-privacy@4ax.com...

If the following doesn't apply then please excuse the blatantly obvious suggestion. ;-)

It also helps if you're model is setup mechanically to fully close the throttle barrel. You need to make sure this is the case. Set the throttle stick to full idle position and the trim full down. Pop the link off the throttle arm and see if you can move the throttle arm itself any further. If you can, then you need adjust the end point adjustment in the transmitter to make up the difference, or you can make the control arm on the servo longer or a combination of the two. If you "do" have to make this adjustment, then also check the full throttle position in the same way. Chances are that if one end is off, the other may be too. Main thing you "don't" want is to have the linkage binding at the extremes.

There's no reason why you shouldn't be able to idle the engine low enough so that the blades aren't turning. In some cases, especially with a new model, the clutch may be a bit tight which will cause the blades to coast along with the engine but it shouldn't be so bad that you can't put your hand on the top of the rotor hub and stop the rotation with just a little pressure. If this is the case, it should get better as the clutch wears in. Hope this helps!

Fly Safe, Steve R.

There is simply no question about it: with helis you MUST be able to stop the engine from the tranny, and the idle position should be low enough to run the engine but not, or barely, engage the clutch. Anything else is unairworthy.

Once you've stopped flying pop your hand flat onto the blade hub to slow them to a halt. FLAT mind you, no dangling piggies!

What model of heli are you running?

Is it a 30, 50, 60 or 90 size? Is it a gasser?

Lay down on the ground on the muffler side and keep your hands below the blades, please. Wriggle yourself over near the muffler, and block the exhaust with your finger. If it gets too hot, have a rag handy and wrap it around your finger and use it to block the muffler. Assuming you are using a glow engine.. The engine should quit immediately.

Yes, assuming you have the throttle set correctly to the servo.

The best way to adjust throttle is to make sure the control arm to the throttle is closed tight when you connect it to the throttle servo at cutoff position with the radio turned on.

To be sure, try starting the engine at throttle cutoff position. If it starts, then you have done something wrong.

Max of Mad

This works especially well if it's a Bell 47 with simulated R/C North Koreans nearby.

? I beg to differ, but thats how I did it when I was a beginning and didn't know any better.

Nowadays, I wouldn't let go of the rotor head, but I'm not there to help him, and you obviously aren't either.

Hopefully he knows better now, since he knows how to get it started. Grab the rotor head when starting. Don't let go unless there is some slack. etc..

Max of Mad

Uh, lay down on the ground and crawl under the spinning rotor blades?? I don't think so. "Not" a good idea.

There's no reason whatsoever that you shouldn't be able to kill the engine from the transmitter. If it's an older model, does it also have an older engine? Engines sold not too long ago came with a mechanical idle stop. A small screw that limited the low end of the throttle travel in the carburator itself. If you've got one of these, it should have a small spring on it that helps to hold it where ever it's set. This needs to be backed off enough so that the throttle can close enough to stop the engine. If your engine doesn't have this, then you need to get the linkage set so that it closes the throttle completely. It's all in the setup.

Fly Safe, Steve R.

Steve,

I know it isn't safe. I'll state it for everybody.

Doing this IS NOT SAFE! You will be visiting a hospital very soon if you do this incorrectly!

There.

But, if you can't get a heli engine to quit, you might try the method I mentioned if you are semi-experienced, and/or not a dumbass.

I was positioning my response for someone who is not experienced and wanting to know how to force a helicopter motor to stop running when his other methods failed, and he asked for help.. I also offered advice to prevent him from using my method in the future.

Max of Mad

On Wed, 28 Sep 2005 18:20:12 -0500, Max of Mad wrote in :

When I first read what you wrote, I was SURE you were pulling his leg.

Then I read the rest of your post and thought about the height of rotor blades and their length.

I saw that your technique would work in many situations.

Better than waiting for the engine to idle through an entire tank.

I'm filing the suggestion away in my bag of tricks. Hope I don't ever need it, but it might come in handy.

Marty

I hear ya Max. I meant no disrespect. It's just that most of us, even those with more than a little experience with these things, tend to grossly underestimate the amount of energy in the rotor blades, even when they're turning no faster than what they'd be doing with an engine running "just" fast enough to keep the clutch engaged.

I've accidentally put my shin into the tip of a rotor blade while leaning over the rotor system to slow it down with my hand. The engine was at a comfortable idle, the clutch was disengaged, and the rotor wasn't turning very fast at all and it still left a respectable cut and knot on my leg. I don't even what to know what it would do to me if it hit me in the head or, God forbid, the face!

As an alternate suggestion, try using some kind of stick to pull the fuel line off the carb. I used a broom handle to do this once. It was still pretty awkward but it kept me out from under the rotor disk. Of course, that's assuming you've got something like that available and the model's not in a fuse.

Just a thought!

I once in the early stages of learning got caught out with the battery going flat on the heli just at point of take off, that was scary as the wind was blowing and trying the lift the heli and it was skidding across the ground, I was helpless, there was no way I could of safely approached it to try and stop it, luckily the nightmare as it seemed ended when the fuel ran out, yet another big lesson learnt on preparation.

Not to be a killjoy, but being a heli-ite on and off...... I do worry about the rest of the heli's setup as the throttle must be about the simplest bit to get right. PLEASE get someone who knows about helis to have a look at it - these bloody things can do you or anyone else a whole lot of damage. I've seen fliers with loads of plane experience come to grief with helis because the setup and mechanical integrity is FAR more critical. Dave :^)

I worry, too. But, I figure the best way is to be helpful first, and remindful if they listen. Telling people they are stupid will get no-one exactly no-where these days..

Especially with model helicopters. Last year, I was test-running my 30 size hawk in the driveway when the neighbor's 13 year and 14 year old daughters came running over and stood less than 10 feet from my heli while I was hovering it 3 feet off the ground.. I landed and shut it off as fast as possible.. They thought it was cool, and they wanted me to let them try flying it. My, "HELL NO!" sent them scampering back home.

I still have nightmares. And I don't test run in the driveway anymore.

Model helis are dangerous. Even leccys are dangerous. A 30 size leccy will be just as cruel as a 30 size glo.

How to get that across to a total n00b requires the knowledge of a teacher.

Max of Mad

I know you meant no disrespect. None taken.

You are exactly right there. From re-reading my earlier responses, I see that it applies to me as well. Sadly true.

The last shin knot I had came from my heli. :) It hurt like hell, too. I had shut down and was reaching to grab the hub to stop the blades, and my shin helped me to do that.

Soon after, I found myself thinking the same thing that you just explained.

A most excellent alternate suggestion. I may just use it next time. I can reach the fuel line on my heli as easily as the muffler. Depending on how full the tank is.. I may have to hold the line to keep fuel from siphoning all over the ground.. I'll figure something out, though.

Max of Mad

That's definately a nightmare situation. I thought about that when I was first getting into helis, and so I bought a battery cycler. I threw a 1400mah batt in for the receiver. I even upped my transmitter battery to 1800mah.

I learned this the hard way with a model airplane..

I recommend that anyone getting into helis do something similar. Get a battery cycler (or borrow one) and check your batt capacity every other month.

Max of Mad

I'm surprised that no one has suggested tossing a coat, jacket or blanket over the machine. Might cause some minor damage but at least no one will bleed.

John L.