title: Curtiss XNBS-4
text: # Curtiss XNBS-4
  
  The Curtiss Model 36 XNBS-4 was a 1920s prototype biplane night bomber built by the Curtiss Aeroplane and Motor Company for the United States Army Air Corps.
  
  ## Development
  
  The XNBS-4 was developed by Curtiss as an improvement on the Martin NBS-1. Two prototypes, AS68571 and AS68572, were built. The design did not enter production because it offered no significant improvement over the NBS-1.
  
  ## Specifications
  
  Data from National Museum of the United States Air Force and Aerofiles
  
  General characteristics
  
  * Crew: 4
  * Length: 46 ft 6 in (14.17 m)
  * Wingspan: 90 ft 2 in (27.48 m)
  * Height: 15 ft 9 in (4.80 m)
  * Airfoil: Curtiss C-72
  * Gross weight: 13,795 lb (6,257 kg)
  * Powerplant: 2 × Liberty L-12A V-12 water-cooled piston engines, 435 hp (324 kW) each
  
  Performance
  
  * Maximum speed: 100 mph (160 km/h, 87 kn) at sea level
  * Cruise speed: 95 mph (153 km/h, 83 kn)
  * Stall speed: 53 mph (85 km/h, 46 kn)
  * Range: 620 mi (1,000 km, 540 nmi)
  * Service ceiling: 13,000 ft (4,000 m)
  
  Armament
  
  * Guns: 5x 0.3 in (7.62 mm) machine-guns
  * Bombs: 1,907 lb (865.0 kg)
  