Electric-powered Tigerkitten "E" purrs
Design and development
Robert Benjamin’s Tigerkitten "E" was derived from a proven design, his Bobcat Mk.2, by reducing the size to fit a .05 motor, reengineering the structure, and taking advantage of the near-total lack of vibration from electric power to achieve weight reduction. The Bobcat’s aerodynamic layout, takeoff performance, and durability were not compromised.
Two Tigerkitten "E" prototypes were built. They were structurally identical but featured different color schemes and power systems; the second prototype incorporated some internal refinements.
Construction and materials
To compensate for the motor and battery weight on the light structure, Robert used good-quality, 4- to 6-pound density, contest-grade balsa. He used Hot Stuff adhesives, primarily thick UFO CA with an occasional shot of fast-setting thin glue.
Covering and finish
- First prototype: covered with Sig Silray cloth dyed with Rit fabric dye, attached and sealed with clear nitrate dope; Stits Polytone used for the color finish.
- Second prototype: covered with Litespan and finished with two coats of clear nitrate dope and two coats of clear Polytone.
- Markings: made to order from Vinylwrite Custom Lettering.
Power system and radio
Robert used Astro Flight cobalt motors in both prototypes with SCR cells (1200 mAh, then 900 mAh) and 11 x 7 propellers (Rev-Up and APC). Throttle control was via Jomar SM-4s.
An Airtronics Championship 7 FM transmitter was used with radio batteries from SR Batteries.
Typical flight duration:
- Approximately 5 minutes with aerobatics
- 6 to 7 minutes with easy flying
Flight characteristics
When trimmed as indicated, the Tigerkitten "E" flew precisely where the modeler pointed it, with just a touch of positive stability in all axes. Robert preferred to land slightly fast, touching down mains first with the tailwheel still in the air rather than a three-point landing.
Invited to a noon demonstration, Robert reported: "In winds that never dropped below 20 mph, the little 'Kitten flew a satisfying basic aerobatic routine, surprising the large crowd with its clean, silent flight despite conditions that would have discouraged many from putting their gas models in the air."
Plans and ordering
The Tigerkitten "E" was featured in the September 1991 issue of Model Aviation (MA) as AMA Plans Service listing 697 and is available for $14 plus shipping and handling. AMA members can access the magazine’s digital library on the AMA website to read more about it. See page 150 or go to www.modelaircraft.org/plans.aspx for ordering information.
Transcribed from original scans by AI. Minor OCR errors may remain.
