Convair YB-60

Convair YB-60
source
Name	YB-60
Caption	The Convair YB-60 in flight
Type	Strategic bomber prototype
National origin	United States
Manufacturer	Convair
First flight	18 April 1952
Status	Canceled
Primary user	United States Air Force
Developed from	Convair B-36 Peacemaker
Developed into	None

Convair YB-60. The Convair YB-60 was a prototype jet-powered strategic bomber developed for the United States Air Force in the early 1950s. It was a swept-wing, all-jet derivative of the Convair B-36 Peacemaker, designed to compete with the Boeing B-52 Stratofortress. Despite its impressive size and performance, the YB-60 was ultimately rejected in favor of the B-52, leading to the cancellation of the program after only two aircraft were built.

Development and design

The YB-60 project originated from a United States Air Force request in 1947 for a jet-powered successor to the Convair B-36 Peacemaker. Convair, leveraging its experience with the massive B-36, proposed modifying an existing B-36B airframe (serial number 49-2676) with a new swept-wing and tail assembly, powered by eight Pratt & Whitney J57 turbojet engines. This design, initially designated the B-36G, promised a significant performance increase over the B-36's combination of piston engines and jet engines. The official contract for two prototypes was awarded in March 1951, with the designation changed to YB-60. Key design features included a 72-degree swept wing, a redesigned vertical stabilizer, and the removal of all defensive armament to reduce weight and drag, relying on high-speed, high-altitude flight for survival. The fuselage, cockpit, and landing gear of the B-36 were largely retained, making it a substantially cheaper and lower-risk proposal than a completely new aircraft like the Boeing B-52 Stratofortress.

Operational history

The first YB-60 prototype (serial number 49-2676) made its maiden flight from Carswell Air Force Base in Texas on 18 April 1952, just three days after the rival Boeing YB-52. Flight testing revealed several deficiencies compared to the B-52; it was slower, less maneuverable, and suffered from stability problems, particularly in yaw. During a competitive fly-off at Wright-Patterson Air Force Base in Ohio, the B-52 demonstrated superior overall performance and handling. Consequently, the United States Air Force formally selected the B-52 Stratofortress as its new long-range strategic bomber in September 1952. Testing of the YB-60 continued briefly, but the program was officially canceled in January 1953. The second prototype, which was nearly complete, never flew.

Specifications (YB-60)

* **Crew:** 5 * **Length:** 171 ft 0 in (52.12 m) * **Wingspan:** 206 ft 0 in (62.78 m) * **Height:** 60 ft 7 in (18.47 m) * **Wing area:** 5,239 sq ft (486.7 m²) * **Empty weight:** 153,016 lb (69,407 kg) * **Gross weight:** 300,000 lb (136,078 kg) * **Powerplant:** 8 × Pratt & Whitney J57-P-3 turbojet engines, 8,700 lbf (39 kN) thrust each * **Maximum speed:** 508 mph (817 km/h, 441 kn) at 39,250 ft (11,960 m) * **Cruise speed:** 466 mph (750 km/h, 405 kn) * **Range:** 8,000 mi (13,000 km, 7,000 nmi) * **Service ceiling:** 53,300 ft (16,250 m)

Variants

Only the two prototype aircraft were built. The first was the converted B-36B (49-2676), which flew as the YB-60. The second prototype (50-2677) was built from the ground up but never completed flight testing before program cancellation. No production variants or further developments were pursued.

Aircraft on display

Neither YB-60 prototype survives today. Both aircraft were scrapped at Convair's plant in Fort Worth, Texas following the program's cancellation. No components are known to be held in museum collections.

Comparison with B-36 and B-52

The YB-60 served as a technological bridge between the Convair B-36 Peacemaker and the Boeing B-52 Stratofortress. It shared the basic fuselage and overall configuration of the B-36, but its swept-wing and all-jet propulsion represented a major advance. However, when directly compared to the purpose-designed B-52, the YB-60's derivative nature proved a handicap. The B-52 was faster, could fly higher, had a superior bombing navigation system, and was more agile. The B-36 remained in service as a nuclear weapon carrier until 1959, but its intended jet successor, the YB-60, was passed over, cementing the B-52 Stratofortress's dominance in Strategic Air Command for decades.

Category:United States bomber aircraft 1950–1959 Category:Cancelled military aircraft projects of the United States Category:Convair aircraft Category:Swept-wing aircraft