The Boeing Model 853-21 Quiet Bird was a US Army reconnaissance plane study developed by Boeing in the early 1960s from their Model 831.^[1] It was an early example of stealth technology, especially electromagnetic low-observability.^[2]

Design and development

Development of the Model 853-21 began in 1962 at Boeing Wichita, only a 1/2 scale prototype was produced which never flew, but tests showed that it had a very low radar cross-section (stealth aircraft).^[1]

Specifications

Data from Boeing^[1]

General characteristics

• Crew: 1
• Length: 33 ft 0 in (10.06 m)
• Wingspan: 33 ft 7.8 in (10.26 m)
• Height: 7.7 ft (2.3 m)
• Wing area: 179.5 sq ft (16.67 m²)
• Airfoil: 65A415
• Empty weight: 6,000 lb (2,721 kg)
• Gross weight: 8,150 lb (3,696 kg)
• Powerplant: 1 × General Electric CF700 , 4,200 lbf (19 kN) thrust

Performance

• Stall speed: 80 kn (92 mph, 150 km/h)
• Range: 1,160 nmi (1,330 mi, 2,150 km)
• Service ceiling: 47,000 ft (14,000 m)
• Rate of climb: 3,050 ft/min (15.5 m/s)
• Wing loading: 45.4 lb/sq ft (221 kg/m²)
• Thrust/weight: 0.52