Signedprinted in black on instrument: BU. AERO. U.S. NAVY / AIRCRAFT NAVIGATIONAL / COMPUTER / MARK 8 / F.S.S.C. No. 85-C-1150 / CONTRACT NO. 99820 G. FELSENTHAL & SONS, CHICAGO
FunctionUsed by the U.S. Navy for altitude correction, air speed correction, speed index.
Instructions printed on instrument: "FOR / AIR SPEED CORRECTION / On the scale above set the air temperature / opposite the pressure altitude on the base. Read / true air speed on miles scale of the base oppo- / site calibrated air speed on minutes scale (Cali- / brated air speed is the reading of the instrument / corrected for instrumental and installation errors.)"
ProvenancePrivate Donor, Troy, NY.