B-50 Superfortress

Infobox Aircraft
name = B-50 Superfortress
type = Strategic bomber
manufacturer = Boeing



caption =

B-50A-5BO "46-10" "Lucky Lady II", the first-ever aircraft to fly around the world nonstop.

designer =
first flight = 25 June 1947
introduced = 1948
retired = 1965
status = Retired
primary user = United States Air Force
more users =
produced = 1947-1953
number built = 371
unit cost = US$1,144,296Knaack, Marcelle Size. "Post-World War II bombers, 1945-1973". Washington, DC: Office of Air Force History, 1988. ISBN 0-16-002260-6.]
developed from = B-29 Superfortress
variants with their own articles = Boeing C-97 Stratofreighter

The Boeing B-50 Superfortress was a post-World War II revision of the wartime United States B-29 Superfortress with larger Pratt & Whitney R-4360 radial engines, a taller vertical stabilizer, and other improvements.

Design and development

The B-50 program began life as the XB-44 Superfortress. One B-29A-5-BN (s/n 42-93845) was modified by Pratt & Whitney in 1944 to accept the larger engines; the resulting "engine testbed" first flew in May 1945. If the engine modification had been included in the B-29 program, the resulting model was to have been known as the B-29D. However, due to other structural changes that would also be necessary to address the increased power, weight and fuel consumption, it was decided to change its military designation to a new model. Since the B-44 program was only for the engine modification, that designation was not considered, and in December 1945 the program was named "B-50 Superfortress".

Officially, the aircraft's new designation was justified by the changes incorporated into the revised aircraft, but according to Peter M. Bowers, a long-time Boeing employee and aircraft designer, and a well-known authority on Boeing aircraft, "the redesignation was an outright military ruse to win appropriations for the procurement of an aeroplane that by its designation appeared to be merely a later version of an existing model that was being canceled wholesale, with many existing examples being put into dead storage."

Revisions to the B-50 (from its predecessor B-29) would result in a top speed just short of 400 miles per hour, faster than many World War II fighters. Changes included:
* Larger engines
* Redesigned engine nacelles and engine mounts
* Enlarged vertical tail and rudder (to maintain adequate yaw control during engine-out conditions)
* Reinforced wing structure (required due to increased engine mass, larger gyroscopic forces from larger propeller, greater fuel load, and revised landing gear loading)
* Revised routing for engine gases (cooling, intake, exhaust and intercooler ducts; also oil lines)
* Upgraded fire-control equipment (to control remote turrets)
* Landing gear strengthening (takeoff weight increased from 133,500 to 173,000 pounds)
* Increased fuel capacity (this was largely addressed by adding underwing fuel tanks).
* Revisions to flight control systems (the B-29 was already difficult to fly; with its increased weight the B-50 would have been much harder to hand-fly).

Redesigned with a larger upper fuselage, the B-50 design would form the basis for the Boeing 377 series of airliners and C-97/KC-97 military transports, with 816 of the KC-97 built. The B-29 and B-50s would be phased out with introduction of the jet powered B-47 Stratojet. [ [http://www.aviastar.org/air/usa/boeing_b-50.php B-50 phase out for B-47] ]

Operational history

Boeing built 371 of the various B-50 models and variants between 1947 and 1953, some serving until 1965.

A reconnaissance variant, the RB-50B (a B-50B conversion) existed and played an important role in Cold War espionage.

An aerial refueling tanker conversion designated KB-50 was used in the Vietnam War.

In 1949, The "Lucky Lady II", commanded by Captain James Gallagher, became the first airplane to circle the world nonstop. This was achieved by refueling the plane in flight.

Although constructed in relatively small numbers, the B-50 was the last member of the B-29 family and was one of the last piston-engined bombers built. The B-50 was retired from its main role as atomic bomber in 1955. A number were converted into KB-50 tankers and lasted long enough to be deployed to Southeast Asia in support of tactical operations.

B-50s were grounded and removed completely from inventory when wreckage of a KB-50 that broke up in flight in 1965 revealed corrosion problems in the fleet.

No flying examples exist today, although several can be found in various air museums.

The USAF Strategic Air Command had B-50 Superfortresses (B-50s and RB-50s) in service from 1948 through 1954.

Variants

* XB-44: One B-29A was handed over to Pratt & Whitney to be fitted with the new Wasp Major 28-cylinder engines. Initially designated B-29D, this was eventually changed to B-50A in December 1945. (x1, converted)

* B-50A--First production version of the B-50. It had new wings that were stronger and lighter than the units on the B-29. It also had taller vertical tail than the B-29. (x60)

* B-50B--Increase in gross weight over the A model, from 168,480 lb (76,420 kg) to 170,400 lb (77,290 kg). Also included a new type of lightweight fuel cell. (x45)

* B-50D--Definitive production version of the B-50. The 7-piece nose cone window was replaced by a single plastic cone and a flat bomb-aimer's window. Many included the new boom-type refueling system. (x222)

* DB-50D--Drone director conversion of a B-50D, to be used with the GAM-63 RASCAL missile. (x1, converted)

*EB-50B--Single conversion of a B-50B to be fitted with a track-tread undercarriage. (x1, converted)

* KB-50--Air to air refueling tanker conversions of the bomber. (x134, converted)

* KB-50J--Tanker B-50s with improved performance, via two extra General Electric J47 turbojets under the outer wings. (x112, converted)

* KB-50K--Tanker conversions of the TB-50H trainer aircraft. (x24, converted)

*RB-50B--All but one of the B-50Bs were converted into the recon role. These were fitted with nine cameras in four stations, weather instruments, and a bomb bay capsule holding the extra crew members. (x44, converted)

* RB-50E--Special photographic conversions of the RB-50B, modified at Wichita. (x14, converted)

* RB-50F--Conversions of the RB-50B, fitted with SHORAN navigation radar for special missions. (x14, converted)

* RB-50G--Conversions of the RB-50B, fitted with electronics countermeasures statios along with the SHORAN radar. (x15, converted)

* TB-50A--Trainer conversion of the B-50A. (x11, converted)

* TB-50D--Trainer conversion of the B-50D. (x11, converted)

* TB-50H--Newly built trainer planes. (x24)

* WB-50 --Weather reconnaissance conversion of the B-50.

* WB-50D--Weather reconnaissance conversions of outdated B-50Ds, fitted with meteorological equipment. (x36, converted)

* YB-50C--Version to be fitted with the Variable Discharge Turbine version of the R-4360 engine. None were built.

* B-54A--Proposed version of the YB-50C.

* RB-54A--Proposed reconnaissance version of the YB-50C.

Survivors

* B-50A-5BO "46-10", ", Planes Of Fame, Chino, California (D) [ [http://www.afa.org/magazine/march1999/0399luckylady.asp Lucky Lady II] ]

* B-50D-115BO "49-310", ex-WB-50D, " 48-114 ", , Dayton, Ohio (D) [ [http://www.nationalmuseum.af.mil/factsheets/factsheet.asp?id=369 USAFM, Wright-Patterson AFB] ]

* B-50D-120BO "49-0351", ex-WB-50D, " Flight Of The Phoenix ", Atwater, California (D) [ [http://www.elite.net/castle-air/boeingwb50.html Castle Air Museum] ]

* B-50D-125BO "49-372", ex-KB-50J, " 372 ", Tucson, Arizona (D) [ [http://www.pimaair.org/collection-detail.php?cid=33 Pima Air Museum] ]

* B-50D-125BO "49-389", ex KB-50J," 48-014 ", MacDill AFB, Tampa, Florida (D)
note: On "46-10" " Lucky Lady II " it has been reported that nose section is not original to this airframe

Operators

;flag|United States|1912
*United States Air Force

pecifications (B-50D)

aircraft specifications

plane or copter?=plane
jet or prop?=prop

crew=8: Pilot, co-pilot, flight engineer, radio/electronic countermeasures operator, two side gunners, top gunner and tail gunner
length main=99 ft 0 in
length alt=30.2 m
span main=141 ft 3 in
span alt=43.1 m
height main=32 ft 8 in
height alt=10.0 m
area main=1736 ft²
area alt=161.3 m²
empty weight main=80,610 lb
empty weight alt=36,560 kg
loaded weight main=121,850 lb
loaded weight alt=55,270 kg
max takeoff weight main=173,000 lb
max takeoff weight alt=78,470 kg
engine (prop)=Pratt & Whitney R-4360
type of prop=radial engines
number of props=4
power main=3,500 hp
power alt=2,600 kW
max speed main=395 mph
max speed alt=343 kn, 636 km/h
cruise speed main=244 mph
cruise speed alt=212 kn, 393 km/h
combat radius main=2,100 NM
combat radius alt=2,400 mi, 3,860 km
ferry range main=5,000 NM
ferry range alt=5,760 mi, 9,270 km
ceiling main=36,650 ft
ceiling alt=11,170 m
climb rate main=2,225 ft/min
climb rate alt=11.3 m/s
loading main=70.19 lb/ft²
loading alt=343 kg/m²
power/mass main=0.115 hp/lb
power/mass alt=193 W/kg
guns=
** 12× .50 in (12.7 mm) M2 Browning machine guns in remote controlled turrets
** 1× 20 mm (0.787 in) cannon in tail
bombs=
** 20,000 lb (9,100 kg) internally
** 8,000 lb (3,600 kg) on external hardpoints

See also

aircontent
sequence=

related=
* B-29 Superfortress
* XB-44 Superfortress
* C-97 Stratofreighter
* Boeing 377 Stratocruiser
similar aircraft=
* Tupolev Tu-4
lists=
* List of bomber aircraft
* List of military aircraft of the United States
see also=

References

Notes

Bibliography

* Jones, Lloyd S. "U.S. Bombers, B-1 1928 to B-1 1980s". Fallbrook, CA: Aero Publishers, 1962, second edition 1974. ISBN 0-8168-9126-5.

External links

* [http://home.att.net/~jbaugher2/b50.html Boeing B-50 Superfortress Joe Baugher's Encyclopedia of American Aircraft]
* [http://www.globalsecurity.org/wmd/systems/b-50.htm B-50 Design and Specifications, Global Security.org]
* [http://www.warbird-central.com/american/bombers/B-29/B-29_serials.html B-29 & B-50 production batches and serial numbers]
* [http://home.att.net/~jbaugher/usafserials.html USAAF/USAF serials 1922 to present day.]