One of those days....

[solentlife]

What surprises me - is my two 2.4Ghz radios which are cheap Chinese .. FlySky 9X and other a 6EHP heli job - both have dedicated throttle hold switches ..

Being a 450 RC guy as well as fixed wing has got me into habit of always flippin that kill switch before I connect LiPo ... when I land and model stops - I flip that switch ....

I've seen and had myself clipped by a prop that started unexpectedly when connecting up. Luckily not as bad result as Wolfe here. But boy did it hurt !
I also flip the switch after landing as I've seen another go up to a model after landing ... NOT the pilot ... and get clipped by prop ! So I avoid both by using that switch religiously.

But word of caution :

I use that kill switch and one time in the house - I have a large banquet / party room that I used to test pitch etc. on my 450 in.
I flipped the switch so motor was dead. Connected all up ... 450 was on the floor. Operated sticks to watch swashplate movement ... something was wrong and I wondered if it was just a bad setting or the radio ... I pressed the keys on front of Tx to enter menu ... changed model memory .... to see if my other settings did same ... that disengaged the Kill switch and the 450 took of in that room at full throttle, still with pitch gauge on one rotor blade ... Hit TV, bounced of, hit ceiling ......... came across the room at full bore straight into wifes Xmas tree ............. tangling up in branches and fairy lights. As it went into the tree it missed me by a hairs breadth ! I felt the rotor wash across my face ....

What had happened was switch was reversed along with throttle on another memory ........ next was FRIGHTENING !!

Lesson learnt ... Wife was p*****d of that her decorations and tree were 'customised' ...

So even that 'kill switch' throttle hold can be not enough when the fools gremlins are at work ....

Wolfe ... hope the hand heals fully and you can get out to play !!

[wolfewinde]

Scary story, Solent.

The hand seems to be fine.

I am just trying hard to get into the practice of moving VERY SLOWLY and deliberately when it comes to plugging in the batteries. Paying close attention to where the radio is sitting, plane pointed away from everyone, double checking "throttle off", and picking up the radio very slowly and carefully so as NOT to bump the throttle, and making sure i already have a hold of the plane where a sudden "throttle on" would not cause any damage before I pick up the radio

I think I was just getting lax after hundreds of flights with no close calls. It is too easy to get in a hurry and not not take a bit of extra time to be careful and fully engage the brain LOL.

Probably was a good lesson - especially since I got away with no real damage to the hand.

Wolfe

[payne9999]

iI looked inside my DX6i and there are two wires going to the throttle cut momentary switch. I am going to put another micro toggle in the radio to kill the throttle.

I am not real comfortable with using the throttle high method when plugging in the plane. I would rather go with a hard switch and rely on the ESC as a secondary system of the radio link was lost.

I suppose the best thing would be an Anderson power pole jumper enable on the motor wires on each plane.

Dave

[Larry3215]

Originally Posted by payne9999

iI looked inside my DX6i and there are two wires going to the throttle cut momentary switch. I am going to put another micro toggle in the radio to kill the throttle.

I am not real comfortable with using the throttle high method when plugging in the plane. I would rather go with a hard switch and rely on the ESC as a secondary system of the radio link was lost.

I suppose the best thing would be an Anderson power pole jumper enable on the motor wires on each plane.

Dave

If your radio link is bad/lost it wont matter if you are using a throttle cut switch or throttle stick position to "safe" the model. Both will be irrelevant if the tx goes bad or link is lost.

The esc will do what ever its built in 'failsafe' dictates - if it has one and if it works.

The removable shunt in the battery lead is the only 100% for sure "safety off"

[John_]

After a few close calls I'm using arming plugs switches on my electric planes. I had a really scary close call, listen to this one, so now I use the Arming Plug Switch system from www/ SharpRC. com.

I converted a nitro SuperSportster MKII to a 1.2KW electric plane, it spins a 11x7 prop at 16,000 RPM. Uses 5S-3600mA at 60 Amps. I nearly got the prop in the face at high RPM in my basement when I was setting it up. Listen to this scenario, which I had never concidered, and it might help you:
1. Turned on Tx, Spektrum Dx6i
2. Plugged in Lipo
3. Did some testing on the elevator, then got called up stairs for dinner.
4. Forgot to unplug Lipo, and turned off Tx. The Rx shut down to the Safe Mode (throttle off, surfaces neutral) and my ESC does not beep without Tx signal, like some ESC's do.
5. Had dinner, and came back down stairs.
6. Did other work for 30 min, then turned Tx with throttle at some high position.
7. Rx had been waiting in Safe Mode position (throttle off, surfaces neutral) for the Tx signal to return. This is what the Rx is susposed to do in the event it temporally looses the Tx signal during a flight!!! Well when it re-found the Tx signal the motor roared to life and the fuselage shot off the bench past my face!!!!!!
8. It took me 1 hour to calm down and figure out what the he*l happened. And learned a valuable lesson.

By the way I've showed this scenario to several Club members on my plane and their planes, and the same thing happens everytime. You can do it yourself. Secure your plane, Tx on, Lipo in, test everything, turn throttle down, Tx off, move throttle up, (make sure plane is secure and everyone is safe), and Tx On!!! And she comes roaring to life.

[Larry3215]

Thanks for the detailed explanation of the problem and the heads up!!

[John_]

Wolfe, that totally sucks, sorry to hear about that. I've had a few very close calls with the electric planes, and been soooooooo lucky. My friend got his middle finger tip cut to the bone right next to me from a 32" foam yak, from just a just a little plane! Now I use the ArmSafe arming plugs switch from SharpRC .com, I've tried a few different ones but these are smaller and have much better current carring capacity.

[dumo01]

By no means am I discounting use of the safety plug, it would have added an additional pause point to check things over, but might not have prevented this situation if the safety plug were not pulled when the Tx was shut off, similar to not disconnecting the battery.
I guess that that a more basic safety rule ( which Lord knows I have violated myself on more occasions than I like to remember ) is don't power the plane up with the prop on unless you really need it for flying or power tests.
Really glad to hear you were on the lucky side of this one.
Thanks for the excellent reminder

[dumo01]

Wolfe

Heck of game by your Spartans. Congrats on the win but I suspect that will put Wisc in an ugly mood for next week
Oh well...., if it were not a night game I could go fly

[constantCrash]

TAKE THE PROP OFF IF YOUR WORKING ON A PLANE. That 5 minutes of work can save countless fingers and maybe your life.

[mred]

Sorry to hear about your hand, but glad it wasn't hurt very bad. I got attacked by an APC electric prop once and that was enough to tell me to stay as far away from that rotating razor blade as possible. I also have a program that I can enter in my radio that will put a two switch arming system on my motor so it won't make any difference in where that throttle is, it won't run unless both switches are set. That's on the Airtronics SD-10G and it works great. The only problem with that was, in the beginning I was all set to go fly and had everything set up and ready to arm the throttle, but forgot that I had to set those two switches. It took me about 20 minuets to remember that I had to set those switches to arm the motor. Meanwhile I was checking everything trying to find out why my throttle wouldn't work. One thing I did learn a long time ago. NEVER stand in front of any airplane during start-up unless you have something to block the plane so it won't move. On electric planes, I stand behind the wing while I hook up the battery and get it ready to fly. Always stand behind the plane while adjusting the needle valve and a 4 stroke WILL throw a prop if it backfires at full throttle. Even double nutting it will not stop it from throwing a prop. I also ALWAYS use an electric starter while starting my engines. Beats getting fingers in the prop any day.

Ed