Was showing friends how the Spark gesture mode operated and had some trouble having it land in my hand so grabbed it and turned it upside down to turn it off. No problem so far. Was flying at a beach house on the shore. Was not near any magnetic sources to my knowledge and did not redo compass calibration.
Then without turning power off to aircraft, connected to the RC and took off. The aircraft lifted off from a deck railing about 10 ft above the beach and then immediately veered to the right and backwards and crashed into a house about 50 ft away.
When recovered, found that the left rear propeller was completely missing and three of the four plastic lenses on the motor mount bottoms were missing, exposing the individual motor LEDs!
Can't understand how the prop would have fallen off to cause this movement? Would that be consistent with that kind of motion, off to the right if the left rear prop fell off just after take off?
It had flown fine during gesture mode and power to it wasn't turned off.
Or would the prop have possibly completely be lost during the collision?
Here's the flight record map and aircraft damage photo.