The Boeing B-29 Superfortress

United States of America
United States of America

side view front view under view

This bomber was responsible for dropping the first A-bomb ever used on an enemy, ever. Also the second... The origins of this bomber go years back, but the first official requirements issue was made in january 1940. Boeing already had experimented with older models which were pressurized, and had a very long range (VLR). When the requirements finally came, Boeing had a big advantage over the competition, having started on a similar project in 1939 already.
The bomber was to have a speed of 400 mph, a range of 5333 miles, and a bomb load of 2000 pounds delivered at the halfway-point at that range.

Versions:

Further pictures:

Boeing B-29 Superfortress in full flight
Boeing B-29 Superfortress in full flight

 

Technical data on the Boeing B-29 Superfortress
Powerplant 4 × Wright R-3350-23 Duplex Cyclone radials with 2 turbochargers, rated at 2200 hp (1640.08 kW) each Role during war
  • Heavy Bomber
Length 99 ft 0 inch Height 29 ft 7 inch
Empty weight 71360 lb Operational weight 138000 lb max
Wing Span 141 ft 2.75 inch Wing Aspect ratio 11.49
Wing Area 1736 sq ft Service ceiling 31850 ft
Maximum speed 358 mph at 25000 ft Cruising speed 230 mph at optimum altitude
Initial climb rate Climb to 20,000 ft in 38 min 0 sec Range 3250 miles typical,
5830 miles max
Fuel capacity internal 5,664 Imp gal (6,803 US gal) plus provision for 2,131 Imp gal (2,560 US gal) auxiliary fuel in a weapons bay tank Fuel capacity external -
Machine guns
  • 2 or 3 × 0.50 inch trainable rearward-firing guns in the remote controlled tail turret, 500 rounds each
  • 8 × 0.50 inch trainable guns in 2 remote controlled dorsal turrets, and 2 remote controlled ventral barbettes. 2 guns per position
Cannons 1 × 20 mm Hispano M2 type B trainable rearward firing in the remote controlled tail turret, 100 rounds (in stead of the 3rd gun)
Bomb load Up to 20,000 lb of bombs in two internal weapons bays rated at 10,000 lb each. Typical load was:
  • 4 × 4,000 lb bombs, or
  • 8 × 2,000 lb bombs, or
  • 12 × 1,000 lb bombs, or
  • 40 × 500 lb bombs, or
  • 50 × 300 lb bombs, or
  • 80 × 100 lb bombs, or
  • 1 × nuclear bomb
Later in the war a couple B-29's were fitted with 1 weapons bay, to be able to carry 1 × 44,000 lb bomb. Other aircraft received underwing hardpoints to be able to carry "Block Buster" bombs.
Torpedoes/rockets -
Crew 10: pilot, co-pilot, bombardier, flight engineer, radio operator, navigator, 4 gunners Naval or ground based Ground
First flight (prototype) 21 September 1942 Operational Service 1943 - 1960
Manufacturer Boeing Aircraft Company Number produced 3,960 total, 2,513 this version
Metric system
Length 30.18 m Height 9.02 m
Empty weight 32369 kg Operational weight 62597 kg max
Wing Span 43.05 m Wing Aspect ratio 11.49
Wing Area 161.27 m² Service ceiling 9708 m
Maximum speed 576 km/h at 7620 m Cruising speed 370 km/h at optimum altitude
Initial climb rate Climb to 6095 m in 38 min 0 sec Range 5230 km typical,
9382 km max
Fuel capacity internal 25.752 liters plus provision for 9.690 liters auxiliary fuel in a weapons bay tank Fuel capacity external -
Machine guns
  • 2 or 3 × 12 mm trainable rearward-firing guns in the remote controlled tail turret, 500 rounds each
  • 8 × 12 mm trainable guns in 2 remote controlled dorsal turrets, and 2 remote controlled ventral barbettes. 2 guns per position
Cannons 1 × 20 mm Hispano M2 type B trainable rearward firing in the remote controlled tail turret, 100 rounds (in stead of the 3rd gun)
Bomb load Up to 0.072 kg of bombs in two internal weapons bays rated at 4.536 kg each. Typical load was:
  • 4 × 1814 kg bombs, or
  • 8 × 907 kg bombs, or
  • 12 × 454 kg bombs, or
  • 40 × 227 kg bombs, or
  • 50 × 136 kg bombs, or
  • 80 × 45 kg bombs, or
  • 1 × nuclear bomb
Later in the war a couple B-29's were fitted with 1 weapons bay, to be able to carry 1 × 19.958 kg bomb. Other aircraft received underwing hardpoints to be able to carry "Block Buster" bombs.
Torpedoes/rockets -

Here is a quick overview of all different versions, without the full technical specifications:

Different versions of the Boeing B-29  Superfortress
Boeing XB-29 Superfortress The prototype of the Superfortress. It was powered by 4 × Wright R-3350-13 Duplex Cyclone radials with 2 turbochargers, and was without defensive armament.
Number built: 3
Boeing YB-29 Superfortress Operational test version of the Superfortress. It was powered by 4 × Wright R-3350-21 Duplex Cyclone radials with 2 turbochargers, and was fitted with defensive armament.
Number built: 14
Boeing B-29 Superfortress The first mass produced and fully operational version of the B-29.Because it was rushed into service there were a great number of technical problems. To avoid a slowing down of production, all aircraft would be flown to a specialised airfield in Kansas, were all discovered problems would be taken care of. In the meantime these solutions were also included in the production lines, and caused an enormous number of "blocks ". These "blocks " all signified one or more major improvements in the design. It is said that the first 175 aircraft had more than 9,900 faults and defects, which were attended too at Salina, Kansas. This number declined during the course of many months when feedback from Salina was fed to the productionlines accordingly.
Because the European Theatre was already supplied sufficiently with B-17's and B-24's, the decision was made to deploy the B-29 in the Pacific war against japan, where it's extended ranges proved to be vital against the Japanes homelands.
After the capture of the marianas, the B-29 came in full range of Japan, and lesson learnt that in stead of daylight bombings with HE bombs at high altitudes the Superfortress would have more effect in night-raid at low-and medium altitudes with incendiairy bombs. The lack of a night-fighter arm meant that the B-29 could strip most of it's defensive armament, and therefor could carry a heavier bomb load.
A number of these aircraft were fitted with the APQ-7 radar bombsight, improving results even more. This radar had a wing-like construction below the fuselage, 14 ft (4.27 m) wide.
Number built: 2,513
Boeing B-29A Superfortress Based on the B-29, but powered with 4 × Wright R-3350-57/59 Duplex Cyclone radials with 2 turbochargers. Also the wingspan was increased to 142 ft 2.75 in (43.35 m), and the forward dorsal barbette recieved 4 guns in stead of 4.
Number built: 1,119
Boeing B-29B Superfortress The last production version of the B-29. Revisions of the aircraft were the removal of all barbettes, and the addition of an APG-15B radar to aim and fire the tail turret's guns automatically.
Number built: 311
Boeing B-29F Superfortress Conversions of 6 B-29's for use in extreme weather conditions, such as Alaska. These aircraft were later converted back.
Number converted: 6
Boeing B-29MR Superfortress Some B-29 were converted to be able to be refueled in mid-flight (R stands for Receiver in this designation)
Number converted: 74
Boeing CB-29K Superfortress Conversion from a B-19 to act as a freighter.
Number converted: 1
Boeing DB-29 Superfortress Conversions to remote control drones and targets like the QB-29
Number converted: unknown
Boeing EB-29B Superfortress Conversions of a B-29 to act as motherplanes for air-launch of the McDonnell Douglas XF-85 experimental aircraft
Number converted: 1
Boeing ETB-29A Superfortress A single conversion of a TB-29A Superfortress, to accomodate the air-launch of 2 F-84B Thunderjet fighters which were attached at each wingtip.
Number converted: 1
Boeing GB-29 Superfortress Conversions of B-29's to act as motherplanes for air-launch of the Bell X-1, X-2 and Douglas X-3 supersonic research aircraft
Number converted: unknown
Boeing KB-29M Superfortress In order to project the global superppower role the US possessed after the war, it had to be able to reach very lang ranges with it's bombers. Because there were ample bombers without immediate successors the decisions was made to refuel their bombers in mid-flight. The flying tankers were known as EB-29B Superfortress., and fueled the B-29MR Superfortress.
Number converted: 92
Boeing KB-29P Superfortress Not happy with the British adopted way of refuelling in the KB-29M, Boeing devised another refueling system. The new system, called "Flying Boom" had a much higher transfer rate, and produced lower drag.
Number converted:116
Boeing QB-29 Superfortress Conversion of B-29's to act as remote controlled targets.
Number converted: unknown
Boeing RB-29A Superfortress Redesignation of the FB-29A Superfortress
Redesignated aircraft
Boeing RB-29J Superfortress Some operational test aircraft designated YB-29J (6 conversions from B-29's) were used as testbeds for new engines, and were powered by 4 × Wright R-3350-CA-2 fuel injected radials. Of these, a couple were used as photo-reconnaissance aircraft, earning the RB-29J designation. 2 Other YB-29J aircraft were converted to the YKB-29J refuel tankers.
Number converted: 2
Boeing SB-29 Superfortress Post-war conversions of B-29's to act as air-sea rescue aircraft with parachute dropped lifeboats.
Number converted: 6
Boeing TB-29A Superfortress Conversions of B-29A's to act as Crew trainers
Number converted: unknown
Boeing WB-29 Superfortress Conversions of B-29's to act as Weather reconnaissance aircraft. These were the last Superfortresses to be in service in 1960
Number converted: unknown
Boeing F-13A Superfortress Conversions of B-29's and B-29A's to act as long range strategic reconnaissance aircraft. The standard equipment were 3 K-17B, 2 K22 and 1 K-18 cameras.
Number converted: 118
Boeing P2B-1 4 Aircraft were transferred to the US Navy to fulfill a long-range maritime search role.
Number transferred: 4
Boeing Washington Mk I for the RAF During the wait for the Avro Lincoln the RAF needed to fill a gap in their long-range bomber arsenal. Some 87 were loaned to the RAF by the USAAF in 1950, and all were returned by 1955.
Number transferred: 87

Remarks:

Like said before, this aircraft is most noted for dropping the first 2 A-bombs. Also it had a number of inventive features, like the pressurized crew cabin (not common for bombers), and later versions having an automated gun turret, equipped with Radar and automatically aiming (B-29 B).
Also, the long distances this aircraft could cover meant that the Allied forces could take the war to Japan, forcing them to invest more resources in defensive measurements in stead of only attacking.

Strengths:

Weaknesses:

 

 

© by Frans Bonné, 2000
Last revision: 9/20/00