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The motor used is an AXI 2820/10 “Outrunner” type brushless motor with a Jeti 40-3P brushless ESC speed controller, (red label, but will explain in the text). The Hobby Lobby recommended battery pack is an 8-cell 1700-mAh NiMH pack. The recommended prop is an APC 10 X 7E. For those interested, the AXI motor designation of 2820/10 refers to the fact that the motor casing is 28 mm in diameter and 20 mm long, with a 10-turn stator!
There are three main battery types used to power electric model aircraft today. The first is the old standby, Nickel Cadmium battery pack (Ni-CD). This is the type battery that powers most radio control receivers and transmitters. Nickel Metal Hydride batteries (NiMH) weigh about the same as Ni-CD batteries but usually have more capacity, more milliamps, for a given cell size (same as regular battery cell size – D cell, AA cell, etc.). The newest and most advanced battery type is called a Lithium Polymer battery (Li-poly). This type offers very lightweight and greater voltage per cell, 3.6 V versus 1.2 per cell for Ni-CD and NiMH batteries.
 
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| BONNIE fuselage/tail, with Polk’s TRACKER-II transmitter, a tachometer and AstroFlight digital meter and the assortment of battery packs that Bob used in this test series. |
A close up showing the Li-Poly battery pack attached to the right side of the AstroFlight digital meter. The other side of the meter plugs into the Jeti ESC located inside the forward fuselage. |
The main purpose of this presentation is to first tell you what a NiMH and Ni-CD battery will do with the BONNIE-20. Then go on to show what improvements might be expected when switching over to the new lithium polymer (Li-Poly) batteries. A total of six battery packs were tried on this motor/prop set up (in the BONNIE). One 8-cell 1700 mAh NiMH pack that was recommended by Hobby Lobby, and 8 cell Sanyo1950 FAUP type NiMH pack, an 8-cell CP-1700 mAh Ni-CD pack and three different types of FMA /Kokam Li-Poly battery packs, several of which employed the new 2000 mAh (20C load capable) cells. All data presented here was taken using the same motor and prop (with one exception as noted).
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