Radical Departure

My Feedback: (13)

I would like to relate an unfortunate accident I had thursday night. My first in 5 years of flying. I hope this post will save someone else from learning this lesson also. I'll start by saying that I'm self-taught and have been flying for about 5 years. 90% of my planes have been electrics spanning a variety of motor sizes. I always approached my planes with safety first, beit on a field or on the bench. But there's a difference between thinking about it and actually thinking about it. When I was a young paratrooper, by the time I hit the 25th jump mark, I thought I knew all about it. Then I made a rookie mistake and came close to messing myself up bad. I came to the conclusion that I knew just enough to be dangerous. I failed to see a situation unwrapping because of my misplaced confidence. I did not know as much as I wanted to think I did. And thats what happened here. Maybe I'm at that dangerous know-it-all point with RC.

I had made some changes to the electronics on my E-Flite mini-ultra stick. It has a 480 Outrunner, 2100 li-po, APC 10x5 prop. I had everything plugged up and all controls worked fine. But.. I needed to reverse all control surface servos. I started with channel one, reverse, clicked over to channel two, reverse, everything going okay, click over to channel three, reverse, BAMM!!!!!! In the blink of an eye the engine jumped to full throttle, and the plane jumped into my left hand. Immediately lots of blood and fingers going numb. The impact had caused the prop to stop spinning but the motor was still humming as I clamped my right hand to the top of my left to slow the bleeding. A quick trip to the hospital and four hour wait confirmed what I already knew, that being several tendons and vessals were cut. 18 or more stitches. I looked like I had been in a knife fight. Tuesday I got to a hand specialist to schedule tendon/vein re-attachment surgery, to be followed with a bout of physical therapy.

I've replayed the events in my mind a hundred times or more. I know what I did. Normally I work with control surfaces from the side or back. But I was rusty with the servo reverse procedure, so I had the booked opened, radio next to it, and plane facing toward me, as illustrated in the radio manual. The first pic is the 'scene of the crime' as I left it. I located the procedure and start stepping through servos. The throttle was in the down position. So when I hit reverse on channel 3, the throttle, 'stick down' was now 'stick up', hence full throttle. Stupid stupid mistake, and a totally unexpected one which could have been prevented by simply disconnecting an engine lead if I was going to be working in front of the plane. Not to mention why I thought I needed to reverse that channel, instead of just blindly going from one to the other. This kind of mistake just never crossed my mind as one that could happen. but it did.

Some will say I got what I deserved, and while I might debate that, in a way they're right. This split second error in judgement will cost me lost time at work, and a large out-of-pocket medical expense even though I have insurance. Any plane I was remotely thinking of buying is off the table. Heck, it'll be a month before I can even hold a box. I share this as a warning, especially those new to RC and starting with electrics, that dispite the small innocent appearance, brushless motors even in the smaller sizes pack a punch equal to a .10 - .15 gas engine. They are not toys, and can become dangerous in the blink of an eye. I hope this will get some of you to examine your own practices and to conscienely consider safety in all your RC activities. I'm going to be 'off the net' for a while so I'm not going to be able to reply to any questions, etc.. in a timely manner. I'll respond to the thread as soon as I'm able, if necessary. Now get out there and go flying!!!!

bkdavy

My Feedback: (1)

Nobody "deserves" to be bitten by the prop. Sorry to hear about your accident. Hopefully the damage will not be permanent.

I work as a safety inspector for the Department of Energy, and I can honestly say that most accidents and injuries occur when people get so used to doing things one way without accident, that they don't recognize if a change occurs that makes the situation hazardous. In your case, the practice of working on your plane on a bench with the battery connected. I would submit that anytime the power is connected to an electric plane, the plane should be positively restrained, much the way a glow igniter should never be attached to a glow plane unless the plane is positively restrained. This simple practice is often overlooked or ignored.

At our club, we built the Meroke field tables so every plane is restrained when its on the bench. Pilots can't override it, and it makes it easy.

Good Luck!
Brad

coolbean

In a sense I would say that electric motors are more dangerous than fuel engines
1. Just because they arn't running now doesn't mean they arn't dangerous.
2. They don't stop spinning until the current is stopped.

GeneG

My Feedback: (11)

Sorry to hear what you had to go through. Coolbean is right, People tend to treat electrics as if they are not dangerous. Not only will the motor start with only 1 mistake (moving the trottle as opposed to the mutiple mistakes required to accidently start a glow engine) but the Electric Motor keeps turning regardless of what the prop is doing. The glow engine will quit while the electric motor keeps trying to move that prop, making a bad situation worse.

I used to fly the bigs ones for a living. You learn quick that you don't just read the steps and you never assume anything. Concentrate and Focus on every step before you move to the next one. Verify everything. On the flight deck I was trained to look and touch every knob and switch before moving to the next one. I still do that today out of habit even at the RC field.

Here's to wishing you a speedy recovery. And of course get back on the horse as quick as you can, the longer you wait the harder it will be to do.

jetmech05

I hope people are listening here. I can see how this can happen to anyone. OH sure sure! you say, not me, but your at your computer, not at the field and you dont have get it in the air itis.
thank you radical for your tail of woe. perhaps you have saved someone.
In the last 2 months I've seen 2 hands bitten by props 1 required stitches the other was a stratched thumb nail.
I work in aviation I know saftey is a habit. be careful

Arrow IV

Radical,
Sorry to hear about your incident, hope you make a full recovery and quick too!! Yeah thats the hard part a prop at rest is a snake in the grass. You don't think about it till it bites you. Don't be so hard on yourself though could have happened to anyone. I know how it went, your concentrating on something else and POW... that one fraction of a second that changes the next few months of your life. Been there, done that...
One other thing, this is for the "Greenies" those APC props may as well be steak knives flyin around the front of that plane!!! Great for performance, BAD for fingers!! Be safe all!!!

Bruno Stachel

My Feedback: (4)

Hal,
I made a very similar mistake with a GWS Slowstick. I turned the transmitter on then plugged the battery in. The motor lit up on full speed, even though I mad sure the throttle was off. I had the transmitter on the wrong plane with a reversed throttle setting. The prop probably would have stopped with little damage, had it hit my arm dead on. But just enough of the blades caught my forearm to give it over a dozen one inch cuts from my wrist to my elbow. Nothing serious, but I endured a few days of stinging and folks asking me if I got attacked by a cat.

I saw two serious prop strikes last year. One by a two stroke engine running high rpm's, and another by a giant scale gasser. The guy with the gasser caught a blade on the wrist, and easily could have bled to death. You could see the vein or artery (the one you check for a pulse) throbbing in the cut. But luckily it was not ruptured. I suppose the tendons protected it. He ended up with numerous stitches and some numbness. Some PT and OT and I believe he's almost back to normal.

Sorry for the gore, but I think it's good to share these prop strike stories. Every time I hear of or see one it makes for a nice course correction for any careless familiarity I may develop.

Dart373

My Feedback: (2)

It does not matter what esc brand, but I had an ESC go bad and just start up a mini funtana on my right thumb/hand. I was reading directions for the programming, and it just lit off with my transmitter 4 feet away... My friend yanked the battery after the plane flew into the wall. I was lucky, 4 stitches... these newer electrice can hurt you. Glad you are ok..

SO.. from now on, any electric can start anytime... period..

Gullwing72

I feel ya, I had my first plane bite me one week after I completed it. Beit not as bad tendon wise, I got 22 stitches in two fingers. That was about two and half years ago. Lets just say any time I work on the any of my planes with the battery plugged in now one wire gets pulled off the motor. I hope all goes well in the future..........GW

Railinrob

+1

I did the exact same thing about 2 months ago and got the meaty part of my thumb about 3/8" deep all the way to the middle of my thumb and the doctor glued it back together with some kind of "skin safe CA" and tape I got off easy.Now if I do anything to do with programming I take the prop off.

AERORICH73

OOOWWW, it hurts just reading your story. I certainly hope the medical people can fix up your
hand to normal again. I have not been eager to mess with the electric scene because of the
possiblity this type of accident would happen to me. Thank you for posting this mishap for all
to read. It should do a lot for emphasizing the extra precautions needed when using electric
power systems in models.

Rich S.

Chocks_Away

I can fully sympathise with you too, I got bitten on my second outing with an IC plane two years ago, and it bloody hurts.
I started it up, and put my hand through the "Invisible" spinning prop without thinking, to remove the glow start - OUCH !
It was only a .40 size on tickover, but managed to cut me 6 times in a split second, and it never stalled the engine, it carried on going.
I thought it had just rapped my knuckles, until I looked down in horror & saw all the blood.
I now fly IC and electric, but have so far been ok since, probably due to being more careful now.

The only way to be safe while setting up electric planes while you have the battery connected, is to remove the prop while you carry out any mods such as setting up your radio, at least if the motor does fire up then, it won't cause you any grief.

Get well soon.

NCIS

I haven't ever been bitten "YET" but that sounds like it had to really hurt. I'm sorry about the mishap. Everyone has a brain fart now and again and you surely didn't deserve that to happen. Good Luck!!!

Gibbs

lrtx1

I took one to the forearm the other day. In front of the plane with a starter, holding on to fuse behind engine...with plenty of clearance between prop and forearm....lol Until oil cause a little slip in the grip. Arm got straight, arm got bloody. No major repairs needed. Just a couple of drops of thin CA.. lol I was extremely lucky. Keep it safe and think about all the what if's.....

Layne

bigchap

always take the prop off when setting up the radio on an electric plane,i learnt that one a while ago! !

LonestarMan

NCIS, don't worry; sooner or later I'm gonna make you earn your bloodwings signed, Prop.[>:]

Arrow IV

Lonestar,
Dude that's not funny.

LonestarMan

Nothin' but love for you man.....[sm=thumbs_up.gif]

Arrow IV

And they say chivalry is dead...

shag555

I had a 40 sized conversion take off on me as soon as I turned on the transmitter. Luckily it was in the garage and my kids were not around. I hadn't flown the plane in months, thus, the procedure of start up wasn't even spit polished. I had the wrong plane, and it full throttled on me. It didn't hit me... Went under my truck and caught the tail on the axle - tore the tail off.

Someone mentioned removing the prop... I know when adjusting my heli, I just pull the motor wires from the esc... Couldn't you do that with a plane too (provided you can get to it), or even build in a manually operated 2nd switch from the esc to the motor??? Even one wire would do the trick on these brushless motors.

I don't fly electric planes anymore, but I'm in to electric helis now... This has me thinking it would be a good idea to put this 2nd arming manual switch in there somewhere... Is this possible???

MPB

SLFlt

My Feedback: (1)

I have a hole in the insulation of my garage door from a similar experience with a Li-Po Brushless system on a Formossa I. Luckily I got away with only a broken prop and dented nose cone. From then on my mantra with electrics is "if the battery is connected, the engine is at idle" (like a gasser). I also don't walk away from a connected electric with my antenna collapsed. That's another story! Press on. Hope you are doing better.

Regards,

-SLFlt

CGRetired

My Feedback: (1)

I just had 5 stitches on my right index finger from doing something similar, not reverse servo, but by being somewhat careless and nonchalant in my handling the electric aircraft. What happened to me was simple carelessness. I was behind the motor when this happened.

My plan was to check motor/ESC current with a WATTSUP meter. All was hooked up and I started to run the motor up. I thought I had the plane secured so it would not move. Well, it was not. When I got about 3/4 throttle, it started to move. I simultaneously hit the throttle and reached for the front of the plane, aiming my hand for the area just behind the motor and in front of the canope. Well, I missed and reached into the prop's rotational disk. What resuted was a clean cut along the side of my index finger that was deep enough for me to head to the ER and get the 5 stiches. All was ok other than that. Full movement and pretty much no pain. PLUS a lesson learned about Electrics and playing with them with the mind wandrering.

DS.

NCIS

LonestarMan,

Thats funny but true.[&o]

Gibbs

LonestarMan

Yeah, I recertified myself about a year ago.... 14 X 8 Zinger wood__ full throttle__ 8800 RPM__going backwards on a starting stand__ I attempted to grab plane and TX at the same time__BAD__ BAD[&o]. Almost split the prop in two__ Now my left wrist looks like I tried to commit Hari-Kari or somethin'.......

8178

My Feedback: (17)

The best approach is to install the prop when you are at the flight line before the battery is connected and remove it at the flight line after the battery is disconnected. When the battery is connected assume that the motor could start at any time!