Electrically Powered Ultralight Aircraft

On Tue, 7 Aug 2007 16:12:16 -0500, "Gig 601XL Builder"
wrDOTgiaconaATsuddenlink.net wrote in
:

Here is a 100hp electric motor. I don't know if it is typical for an
electric motor but damn the thing weighs over half a ton. I might make the
601XL a little nose heavy. But it's priced right up there with a Lyc of
equal power.

http://www.baldor.com/products/detai...neralPur pose

Catalog Number: D50100P
Description: STOCK MOTOR,368AT,100HP,1750/2000RPM,DPFG
Ship Weight: 1,118 lbs.
List Price: $21,195
Multiplier Symbol: N2


Right. Those are the type I used to install in the early '70; that
was about forty years ago. Today the situation is a bit different.

Here's a small electric motor manufactured by the same fellow, Bob
Boucher, who designed the Sonex motor:


http://www.astroflight.com/store/sto...y3CKHwWtA02470

Cobalt 90 Direct Drive Motor
Cobalt 90 Direct Drive Motor, 30 to 40 cells, 1500W

Astro 90 Cobalt Motor p/n 690
Model No. p/n 690
Name 90 Cobalt
Armature Winding 10 turns
Armature Resistance 0.111 ohms
Magnet Type Sm Cobalt
Bearings Ball Bearings
Motor Speed /volt 256 rpm/volt
Motor Torque/amp 5.3 in-oz /amp
Voltage Range 24 to 48 volts
No Load Currrent 3 amps
Maximum Continuous Current 35 amps
Maximum Continuous Power 1200 watts
Motor Length 3.7 inches
Motor Diameter 2.1 inches
Motor Shaft Diameter 0.25 inches
Prop Shaft Diameter 5/16 inch
Motor Weight 32 oz


Expected Performance of Cobalt 90
Battery Prop Amps Watts Rpm
36 Nicads 14x7 20 amps 800 watts 9,000 rpm
36 Nicads 14x10 25 amps 1000 watts 8,500 pm
36 Nicads 15x10 30 amps 1200 watts 8,000 rpm
36 Nicads 16x10 35 amps 1400 watts 7,500 rpm


This is a small motor, as you can see, but it uses ~1,500 watts, so at
720 watts per horsepower, that's about two horsepower, and it weighs
32 oz, or about two pounds. That works out to about one horsepower
per pound for this type of motor. I have no idea if a one hundred
horsepower motor of this type would weigh 100 lbs or not, but it seems
reasonable.