"http://www.wired.com/wiredscience/2012/03/human-bird-wings-hoax/ "

"Mechanical problem? A prop adapter slipping or the motor axle?"

"The motor can't pull more power than the battery can give.  I have had a flip caught on video and posted here  http://www.availabilitydesign.com/Downloads/UAVCrash.html  - there is more power applied as you can hear but the cause…"

"Could be I manually calibrated each ESC. I have read in the forms to use a hand programmer to make sure they all have the same settings. I have noticed one ESC has breaking turned on while the others do not. I am also wondering if the motors are…"

"I don't know much about quads but isn't there some sort of balance calibration for the escs to be done before flying?"

"You can use a drill press as a press to remove the shafts. Just put a drill bit in backwards."

"If you plug all the ESCs into the board depending on how the ESCs regulate voltage they might fight with each other and things could get hot. "

"In my humble opinion those motors were under powered for that frame. I am flying at 8500ft so I wonder if that has something to do with it. "

"Or from inside Germany:  www.lipoly.de   I use them a lot and they are cheap and very fast."

"I buy my APC props from these guys in Dayton, Ohio.  radicalrc and ecubedrc.  Its the same store. Fast service and cheap shipping."

"The point is that it's hard to find sets of both-handed props in most sizes. 10x4.5 and 12x4.5 seem to the only ones widely available, 10x4.7 props exist too but are not that easy to find (or cheap!)."

"I made a quad with high kv motors. It works fine with the 10x4.5 props but I wonder how it would work with 10x3 props."

"Just search ebay for 10x4.5 propeller."

"Hi Matthew   I guess these seem like the main sizes for the copters, have you a "special" size in mind?   Martin"

"Thanks Martin,   Where to buy in the USA. Seems like there should be more choices of different props.   Matthew"