Virtual Museum - Navigation Instruments

Ref. No. 866.  US NAVY SEXTANT (BUBBLE) TYPE A-12. Plate on side reads “US Navy Sextant (Bubble) Type A-12 Serial 536-43 Contract No. NXS 6417 Mfr’s Drawing No. 11734 Link Aviation Devices Inc.”  Second plate reads “Patented US D132977 Patents Pending United States Great Britain Canada.”  Sextant comes with various accessories including battery cylinder, light bulb and fitting that goes into top of cylinder (the cylinder is inserted into the sextant for night use), spare filters (dark green, red, medium green), springs, battery sleeve and spare recording reel. The sextant is housed in a wooden box covered with khaki material and measures 320 mm x 110 mm x 205 mm.  Same tag as is on sextant is on outside of box.  Written on top of box in red paint is “NZ4008”, which is the serial number for an RNZAF Consolidated PBY-5 Catalina which flew in the Pacific Theatre.  This aircraft had the construction number of 1332 and was previously JX230. 
Ref. No. 7. ASTRO COMPASS MK II, circa 1940, Order No 42-20418-P, Part No 0500, Sperti Inc Cincinnati, Ohio, USA. Good condition, excellent bubble levels, sight glass slightly chipped.
Ref. No. 4. BUBBLE SEXTANT MK 1X A No 12612/42, 1942, Used RAF training command 1940-43 on Avro Ansons in England. Fully functional. Comes with 24 volt adaptor and case.
Ref. No. 247. U.S.NAVY BUBBLE SEXTANT AND CARRYING CASE. Circa 1940’s. Data plate on bottom reads “Sextant - Bubble Type (with altitude averaging device) AN-5851-1 Mfrs. Part No. 3014-2-B Mfrs. Serial No. 9517. Contract No. NOA(S)-2674 Bendix Aviation Corporation, Eclipse, Pioneer Division” Sticker on bottom reads “F.S.S.C. No. 88-S-350”. Fully padded plastic coated green canvas carry bag has “Case Sextant Carrying. BU. Aero., U.S.Navy, Stock No. R88-C-255. Mfrs. Part No. BX-22, Bendix Aviation Corporation, Eclipse, Pioneer Division, Teterboro, New Jersey, U.S.A.” plus “Handle With Care. This case contains precision Instrument. Remove batteries from battery case before stowing. Do not stow sextant in case unless averaging mechanism is unwound.” Case includes mounting arm which reads “Arm-Sextant Suspension. Stock No. R-88-A-595 For use with Pioneer Sextant AN-5851 in navigation dome,” plus extra rubber eye cup.
Ref. No. 97. OBSERVERS COMPASS - TYPE O6A. Circa 1940. Air Ministry. 98mm across. 190mm length (excluding prisim). Complete with case and bakelite holder for mounting in aircraft. Ref No. 6A/1248. No. 17569.H. Black. Handle takes battery for thumb activited light.
Ref. No. 497. PELORUS-DRIFT SIGHT MARK II-B. Circa 1940s. Complete in box with instructions. Sight includes brass shaft and sighting tube plus base plate with scale and small wood block. Label on box reads “Pelorus-Drift Sight, Mark II-B, Bu. Sero, U.S.Navy, Contract No. NXS-4557, F.S.S.C. No. 88-S-840, Aerial Machine and Tool Corp., 260 West Street, New York, N.Y.” In addition to instructions, the box includes a brass tube, split pin in small container and a bag of silica drying compound.
Ref. No. 107. DRIFT SIGHT MARK 2-C. Circa WWII. Exterior label reads "Base Drift Recording Mark 2-C Pelorus DRIFT SIGHT BU. AERO. U.S.NAVY Fssc No. 88-B-110 Contract No. NXS-8588 Waltham Watch Co. Waltham. Mass. Approx. measurements are 165mm length, 130mm width and 80mm high. Top consists of disc with 360 degree graduations and a drift scale. A winding mechanism on the right side and a switch on the left rotates a roll of paper within and the drift is recorded by a pointer.
Ref. No. 63. COMPUTER, AIR NAVIGATION, DEAD RECKONING TYPE MB-4, Circa 1940's. Serial No AF5804958. Spec MIL-C-5414B, Contract No N383-51576A, Stock No R6605-224-7478-V170, MFRS Part No FAA-46C, G Felsenthal & Sons Inc, U S Government Issue.
Previously owned by Charles Kelly, who flew with the RAF Pathfinder Force.
Ref. No. 62. HEIGHT AND TRUE AIRSPEED COMPUTER Mk 1V. Circa 1930's. Broad arrow. Ref No 6B/345. True air speed and altitude computer.  Previously owned by Charles Kelly, who flew with the RAF Pathfinder Force.
Ref. No. 30. COMPUTER, HEIGHT AND AIR SPEED. Mark 1, Circa 1936. Computer in mahogany box 165mm X 165mm X 40mm. Brass plaque on front reads "COMPUTER, HEIGHT AND AIR SPEED, MARK 1, THE LONDON NAME PLATE Mfg. Co. Ltd. LONDON & BRIGHTON, SERIAL NO.3571/36 STORES REF. NO. 6B/108". Computer 145mm diameter.
Ref. No. 645. COURSE AND SPEED CALCULATOR MK II. 1940. RNZAF. Ref. No. 6B/119. H.T.A. (1928) Ltd. 66/40.
Ref. No. 56. NAVIGATIONAL COMPUTER. Circa 1940. Air Ministry. MK 111D REF No 6B/180. Serial No 12544/40. Bakelight base. Aluminium upper. Perspex window. Includes notebook. Grid below perspex is probably linen and is rotated via knob lower right. Useful speeds up to 400 knots.
Ref. No. 89. COMPUTER DEAD RECKONING MK 4A. Circa 1950. Ref No. 6B/2645. Air Ministry. Made by the London Name Plate Mfg Co Ltd of London & Brighton. Came with brown canvas cover with broad arrow on front. Includes computations for converting TAS to Mach No. Inscribed C.W.B.Kelly, who flew with the RAF Pathfinder Force.
Ref. No. 90. COMPUTER DEAD RECKONING MK 4A. Circa 1950. Ref No. 6B/2645. Air Ministry. Mat covering. Includes computations for converting TAS to Mach No. Inscribed W.M.McLeod, who was a W/O RNZAF pilot who also flew RAF Lancasters.
Ref. No. 93. "DOUGLAS PROTRACTOR", Circa 1970, W & G Precision Instruments, Australia. In cardboard cover with instructions. .

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