Details and Image
|Type||Model #.||Aircraft Maker / Name||Instrument Maker||Country||Construction||Date||Scale Length||Area of Use
|Disk||DH-114||de Havilland / Heron||de Havilland||U.K.||Matal||est. 1950's||Dia. = 17.8 cm||Flight Management
Comment: "1) Used for weight and balance calculations to make sure the aircraft is not tail heavy or nose heavy 2) A vey well made slide rule with a main disk and 2 smaller concentric disks, one on each side."