Flight, May 1934

THE B/J OJ-2 OBSERVATION AIRCRAFT
Generally similar to the OJ-1 Observation Machine supplied in quantities to the U.S. Navy

   BUILT primarily for observation work with the U.S. Navy, the B/J OJ-2 machine, constructed by the B/J Aircraft Corp. of Baltimore, Maryland, is readily adapted for Army Cooperation work or for use as a commercial two-seater. It may be used as either a landplane or a seaplane. The machine is of metal construction with fabric covering, except for the wings, which are of wood. Either the Pratt & Whitney "Wasp Junior," of 400 h.p., or the "Wasp Senior" 550 h.p. may be used. Although originally produced with open cockpits, the machine may be supplied with a cabin top. A large amount of work with Zap flap and aileron installation has been done on this aircraft.
   The fuselage is of welded chrome molybdenum steel truss type with duralumin channel fairings. Metal sheet is used to cover the forward portion, while the rear, except the "turtle" deck, is covered with fabric. The engine mounting is detachable. Wooden construction is mainly used for the wings. The spars are of the wooden box type, with flanges of spruce and webs of plywood. The ribs are of the truss type, made from spruce and plywood. Duralumin tubular compression struts and swaged steel wires are used for the drag system. Duralumin sheet extending to the rear of the front spar on both surfaces forms the leading edges. Frise ailerons are fitted to all four planes. Duralumin construction covered with fabric is used for the tail surfaces. The tail plane is adjustable from the pilot's cockpit in flight.
   An undercarriage of the conventional split type may be fitted, or a cross-axle type with an internal splined shock absorber leg, which allows the whole to travel in a vertical direction only, the remainder of the gear being rigidly stressed. The tail wheel is of the swivelling type rotating through 360 deg., and may be locked from the cockpit. For use as a seaplane, the aircraft is fitted with a central main float and two wing-tip floats of duralumin construction. Within the fuselage is tankage for 90 gall, of fuel. When the "Wasp Senior" engine is installed, two auxiliary tanks of approximately 20 gall, capacity each may be installed. A Hamilton Standard metal airscrew and low-drag wing cowling are generally used.
   Provision is made for the installation of wireless, emergency flotation gear and pyrotechnics. One fixed 0.30 calibre Browning gun is installed in the starboard side of the upper centre-section, and another Browning gun is mounted over the rear cockpit. Five hundred rounds of ammunition are provided for the fixed gun and six hundred rounds for the rear gun. Bomb racks may be fitted to the port lower wings of the "Wasp Junior" model, and on both lower wings of the "Wasp Senior" type. A total bomb load of 500 lb. may be carried by the more powerful version, while the "Wasp Junior" powered type carries only 250 lb.
   The table applies to the standard OJ-2 fitted with the Pratt & Whitney "Wasp Junior." When fitted with the "Wasp Senior" and a cabin top over the cockpit the top speed at sea level is estimated to be 175 m.p.h., the normal range at cruising speed 548 miles, the maximum range 790 miles, and the absolute ceiling 19,200 ft. With an engine rated at 500 h.p. at 11,000 ft. the estimated speed at that height is 190 m.p.h.

B/J OJ-2
Pratt and Whitney "Wasp Junior"

DIMENSIONS
   Span 33 ft. 8 in. (10,28 m)
   Length 25 ft. 8 in. (7,84 m)
   Height 10 ft. 10 in. (3,30 m)
   Wing area 284-2 sq. ft. (30,65 m)

WEIGHTS
   Weight empty 2,323 lb. (1 058 kg)
   Useful load 1,390 lb. (631 kg)
   Gross weight 3,713 lb. (1 688 kg)
   Wing loading 13-1 lb./sq. ft. (63,9 kg/m2)
   Power loading 8-9 lb./h.p. (4,03 kg/h.p.)

PERFORMANCE
   Speed at sea level 154 m.p.h. (248 km/hr)
   Speed at 5,000 ft. (1 525 m) 150 m.p.h. (242 km/hr)
   Speed at 10,000 ft. (3 050 m) 142 m.p.h. (228 km/hr)
   Speed at 15,000 ft. (4 575 m) 121 m.p.h. (195 km/hr)
   Stalling speed 57 m.p.h. (92 km/hr)
   Climb to 10,000 ft. (3 050 m) 12-1 min.
   Service ceiling 15,300 ft. (4 660 m)
   Absolute ceiling 16,700 ft. (5 090 m)
   Range at cruising speed 530 miles (854 km)