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        Video A iPhone shot down my radian :D

#1 acetech09 Sep 02, 2012 10:41 AM

A iPhone shot down my radian :D
 
1 Attachment(s)
I'm doing a slow flyby of the strip when my friend starts recording with his iPhone. Only a few seconds after he starts recording (movie not edited) my engine gives out and I have to land. I was already about 30 mins into a thermal flight, and the failure happed right after he started filming. I CALL SHENANIGANS! (sarcasm)

Just listen to the audio. Sorry I don't have a better video - he emailed it to me in low quality.... but you can get the point.

Radian Motor Fail (0 min 8 sec)


EDIT: The Radian gets its revenge

#2 bobthenuke Sep 02, 2012 01:22 PM

Several years back this was an issue with Multiplex EVO. FWIW.

#3 carlsoti Sep 02, 2012 08:04 PM

I'm calling BS. You flew for 30 minutes, then expected a full throttle zoom? I think the expectations of your equipment are more likely to blame than Apple.

#4 acetech09 Sep 02, 2012 08:34 PM

It's a radian. + thermals. And a 2200mAh battery. Do you soar much?

Standing voltage was at 3.8-3.9v upon landing. Was low, and might have triggered the cutoff, but I wouldn't expect a cutoff to make that weird grindy noise.

#5 carlsoti Sep 03, 2012 12:17 AM

I didn't hear the weird grindy noise. My mistake. I didn't realize that's what it was you were talking about. I'm still not convinced the iphone had anything to do with it. The rf band it operates in is nowhere near 2.4g or 72mhz. It's possible a harmonic could intersect the fequency, but at such a low power, it's not likely. It could be a bearing going bad. That could cause all the issues seen. Bad bearings can be grindy. A grindy bad bearing could also spike the amp draw, knocking down the voltage of the battery, and trip the LVC. The grinding metal against metal can also produce rf that can interfere with a wide swath of the rf spectrum.

EDIT:Actually, listening back to it, it sounds like the motor is spinning in the collet. Been there, done that. Check it out. If that's the case, you need to scruff up the motors output shaft, and make sure there's absolutely NO trace of any lubricant inside the collet./

BTW, yes I do soar. Nothing I'd consider putting a 2200 in, though. I've got a couple EasyGliders, one is pure glider, the other flies on a 1300 because I don't have anything smaller, and a fleet of busted up DLGs from my previous cycle F3K campaign. It didn't go as well as I had hoped, but my buddy George went to Sweden and placed 2nd in the world, just behind Joe Wurts. As things are going right now, he's in a spot to make another run at the gold, and I still have a pile of broken gliders. :D

#6 acetech09 Sep 03, 2012 10:22 AM

Quote:

Originally Posted by carlsoti (Post 22625152)
The rf band it operates in is nowhere near 2.4g or 72mhz. It's possible a harmonic could intersect the fequency, but at such a low power, it's not likely. It could be a bearing going bad. That could cause all the issues seen. Bad bearings can be grindy. A grindy bad bearing could also spike the amp draw, knocking down the voltage of the battery, and trip the LVC. The grinding metal against metal can also produce rf that can interfere with a wide swath of the rf spectrum.

Heh... I was joking about the iPhone thing... I'm pretty sure it was a coincidence. I'll check the collet.

#7 acetech09 Sep 03, 2012 07:39 PM

Collet seemed to be the problem. There was quite a bit of play. Tightened it down, and spent about 4 hours today at the field soaring. Taped my iPhone to the bottom of it and did some impromptu aerial photography :D

#8 RCSwitz18 Sep 04, 2012 10:51 PM

Quote:

Originally Posted by acetech09 (Post 22632436)
Collet seemed to be the problem. There was quite a bit of play. Tightened it down, and spent about 4 hours today at the field soaring. Taped my iPhone to the bottom of it and did some impromptu aerial photography :D

Yeah, i wouldn't do that :D
Hopefully the tape was strong!

#9 acetech09 Sep 04, 2012 11:00 PM

Just finished editing the video - and uploading to youtube now. Should be done in about 40 mins:


The iRadian (4 min 48 sec)


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