World War Photos

Beaufort L4449

Detailed Construction of the Beaufort

The Bristol Beaufort, a British twin-engine torpedo bomber, was primarily constructed from light alloys, with wooden doors and fabric-covered control surfaces. The design emphasized sub-component assembly and interchangeability between components, a characteristic of many Bristol designs of the period.

• Fuselage: The Beaufort’s semi-monocoque fuselage was built in three sections, shaped by lipped channel and Z-section formers, with multiple formers used at fuselage joints and other stress points. The fuselage was further strengthened by angle-section stringers. Most of the construction utilized Alclad or aluminum, but Hiduminium sections were used at the fuselage/fuselage and fuselage/wing joints.

  • Forward Fuselage: Extending forward from the wing’s front spar, this section housed the pilot and navigator/bomb-aimer. An armor plate was installed in front of the instrument panel for their protection, but the V-windscreen, which incorporated clear vision panels and a ring-and-bead sight for the fixed guns, was left unprotected. When a torpedo sight was fitted, it was positioned above the pilot’s head.
  • Rear Fuselage: This section extended aft from the front spar to the stern frame, accommodating the Wireless Operator/Air Gunner (WOp/AG) and the rear gunner. The area near the turret was reinforced with three heavy longerons.
    • Aft of the radio compartment, which was situated between the wing spars, was a chemical toilet that also functioned as a step, followed by the 27-inch wide, two-part main entrance hatch. The cabin had a width of 54 inches.
    • To provide the turret gunner with a better field of fire, the fuselage was cut away in an inverted “V” shape aft of the turret.
    • The stern frame supported the horizontal and vertical tail surfaces and the self-centering tailwheel, which retracted into a waterproof well but was frequently locked down.

• Bomb Bay: Initially designed to be 100 inches long, the bomb bay was widened to 60 inches to accommodate four Small Bomb Containers side-by-side with the bomb doors fully closed. This gave the lower fuselage its distinctive bell-shaped cross-section.

  • Bomb Load: The bomb bay could hold a variety of payloads, including:
    • Four 250 lb anti-submarine bombs side-by-side
    • Two 250 lb “B” or 500 lb general purpose (GP) bombs
    • Two 250 lb bombs plus two 500 lb GP/medium capacity (MC) bombs
    • Four slim 500 lb semi-armor-piercing (SAP) bombs
    • Four 250 lb depth charges
  • Torpedo Carriage: The bomb bay could also be fitted with a special rack to carry a torpedo, a magnetic mine, or a 2,000 lb bomb. Fore-and-aft extensions formed the 19-foot torpedo cell.

• Wings: The Beaufort featured cantilever wings with an RAF 28 airfoil section. These were constructed in three main sections, with the outer panels bolted to the outer ends of the center-section spars. Two span-wise spars, incorporating full-depth webs and top and bottom extruded Hiduminium booms, formed the foundation of the wing structure.

  • Center Section: The center section extended through the fuselage, carrying all weights and forming the roof of the bomb bay. Near the outer ends of its parallel spars, square-section steel-tube mounts on tubular bearers were installed for the engines and main undercarriage, which were housed in streamlined nacelles. Two main fuel tanks, each holding 194 Imp gal, were situated inboard of the engine mounts, between the spars.
  • Outer Panels: The spars of the outer wing panels tapered and converged towards the detachable wingtips. These panels housed an oil cooler and a 91 Imp gal fuel tank, each with a fuel jettison pipe, located just outboard of pickup points for an external 250 lb bomb carrier.
  • Armament and Other Features: The leading edge of the port outer wing contained twin adjustable landing lights, and a fixed .303-inch caliber Browning gun with 300 rounds was positioned inboard of the lights.
    • The ailerons were made from Alclad ribs on a tubular Duralumin spar. Hydraulically operated split flaps were installed between the ailerons and the fuselage. A four-man inflatable dinghy was stored in the port wing root.

• Tail Surfaces: The tail surfaces were built with similar construction to the ailerons, using Alclad ribs on a tubular Duralumin spar. Both the elevators and rudder were similar in design to the ailerons.

The Beaufort was a larger aircraft than the Blenheim, despite having only a 2-foot greater wingspan. However, due to refinements in design and the extensive use of high-strength light alloy forgings and extruded sections, its structural weight was proportionately lower. The center-section was inserted into the rear fuselage, and the nacelle structure was integrated into the ribs where the main undercarriages were attached. Both the front fuselage and the stern frame were detachable at jig-drilled transport joints, as were the outer wings and wingtips. This construction made the Beaufort well-suited for sub-contract manufacturing, as components could be transported by road or rail and then assembled at a central location.