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390mg Plane - My Lighest Plane & Unoffical Record Holder

To date, this is the lightest plane I've ever built. It held the unofficial record of the world's lightest plane for about 4 months back in July of '08 until it was bested by one weighing 225mg. To date, I don't believe any lighter ones have been made.

This plane is my crown jewel of micro plane accomplishments... Despite the mountain of headaches it took to build. It has a 3.1" wing span, a 1" chord, and is 3.5" long. Flight times were surprisingly high, around 4-5 minutes, considering the size of the motor. An infrared transmitter/receiver system was used to control the throttle and rudder. The rudder control is done though an electromagnetic actuator.

The frame is made of carbon fiber rods ranging in size from 0.01" (0.25mm) to 0.005" in diameter. All the rods less than 0.01" diameter were hand sanded down to size. The covering on all the surfaces is OS film (DuPont).

All the electronics in the IR receiver - microprocessor, FET, and IR detector - were sanded down to reduce weight. The aluminum that encases the 8.5mAh lithium polymer battery was trimmed away to get the battery weight lower. Even then, the battery weight was 75% of the plane's weight.

The motor and propeller were custom designed & built to power this plane. The motor is a single phase brushless design swinging a 0.6" prop. A video of it can he seen here.

Weight Breakdown:
Airframe + Act: 37mg
8.5mAh Li-Po + On/Off Switch: 290mg
IR RX: 25mg
BL Motor: 30mg
Prop: 5mg
Landing skids: 3mg

All up Weight: 390mg

Original Post: 390mg Plane on RcGroups


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3D Printed Mechanical Pencil

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