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Nov 14, 2006, 03:15 PM
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Battery discharge rates, more rain, and camera baseball


Based on the recharge time, we have an approximate discharge rate for hauling camera, camera table, LEDs, and 4000mAh battery: 14 Amps The following discharge rates are based on flight times and rated capacity:

LEDs and 3300mAh battery: 7.9 Amps
LEDs and 4000mAh battery: 8 Amps
3300mAh battery: 7.333 Amps
4000mAh battery: 6.9 Amps

Definitely approximate due to the uneven wear on the batteries. Also there were a few 30A spikes in there.

So the video returned from our first night camera flight was useless but interesting. Looked like a lunar takeoff near the ground, with the shadow of a spaceship drifting away, and a night airline flight in the air. Complete blackness most of the time with an occasional cluster of lights and faint silhouette of the horizon, making you think there's a seriously skilled pilot flying the copter.

Camera mount #5 was nihilistic. The takeoff orientation required lifting off at normal throttle, then as soon as the cables tightened, gunning the throttle to lift the camera before losing control.

The first attempt, in high winds and drizzle, used a gradual throttle increase with aggressive corrections to keep the camera on the ground until the last inch of cable was tought. This resulted in completely tangled cables and a camera which couldn't be righted, but a perfect landing.

The second attempt involved gunning the throttle and letting the cables snap into position, in 20mph wind. This caused 18 seconds of completely erratic flailing of the camera in a 2' circle. Managed to keep it in the air by concentrating on the rotor, but the camera looked like a brick about to break lose and the swaying circle was growing exponentially. Got it under 3' and let it crash. Destroyed the antenna.

After that, managed 25 minutes of flying in light rain and 20mph gusts without the camera. Just let the wind blow it into random orientations to escape from, all successfully with one unintended touch & go. Winds shifted between North and South constantly, resulting in forward flights to opposite sides of the field to keep the nose out.
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