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Bell D-36

United States (1950)

Detailing the development and operational history of the Bell D-36 All-Weather Heavy Fighter / Night-Fighter Aircraft Proposal.

 Entry last updated on 7/24/2017; Authored by Staff Writer; Content ©www.MilitaryFactory.com



  Bell D-36  
Picture of Bell D-36 All-Weather Heavy Fighter / Night-Fighter Aircraft Proposal


The proposed mixed-powerplant Bell D-36 all-weather fighter had a poor showing against rivals when presented to USAAF authorities.

The pace of technological developments concerning military aircraft during World War 2 (1939-1945) showcased to American warplanners that many new types would be required after the war in order to meet all-new over-battlefield demands. In August of 1945 characteristics were fleshed out for several new category designs and one of these formulated to become a new United States Army Air Forces (USAAF) all-weather heavy fighter / night-fighter.

The wartime version of the heavy fighter was typically a twin-engined platform armed with machine gun and cannon armament for ground attack actions and air-to-air combat. An inherent bomb-carrying and rocket-launching capability were added to many of these designs to produce a true multirole performer. These aircraft were usually crewed by two personnel (though the Lockheed P-38 Lightning required just one) and were deployed on all manner of sorties against the enemy.

The committee agreed upon several performance factors - a minimum top speed of 550 miles per hour and a combat radius of 1,000 miles. Standard, fixed armament would be 6 x 0.50 caliber Heavy Machine Guns (HMGs) or harder-hitting 4 x 20mm cannons in their place. Of course the design would also have to include an inherent bomb-carrying capability and support the launching of high-velocity rockets to contend with most any mission set thrown its way.
Bell joined others in submitting possible designs for review and their offering came in the form of the "D-36". Engineers elected for a high-winged monoplane form which sat the cockpit aft of a short nosecone but ahead of the wing mainplanes. The wing mainplanes would house nearly all of the proposed fuel stores allowing the fuselage section to contain all other mission-pertinent components including armament, crew spaces, radar and avionics. The tail was raised and capped by a single vertical fin afforded mid-mounted horizontal planes. A tricycle undercarriage was envisioned. The engines were installed by way of nacelles fitted into each wing, underslung in the usual way and running from beyond the wing leading edges to the trailing edges. Each engine would power a three-bladed propeller unit though it was expected that a four-bladed assembly would be featured in the future without much change to the powerplant scheme. A crew of two, the pilot and a radar operator, were to be seated side-by-side in the wide cockpit setting.

The General Electric TG-100 (T31) turboprop gas turbine engine was to take up its position in each wing to supply conventional power with provision made to adopt a larger, more powerful engine in the near future. A drive shaft was intended to join the pair at the fuselage allowing one engine to drive the other propeller as needed - a fuel-savings feature as well as a security measure should one engine fail. The propellers rotated in a "counter" action to eliminate torque manufactured by either installation and each held a reverse-pitch function to quickly decelerate the aircraft in-flight. There was also additional power to be provided by 2 x Westinghouse 24C-6 turbojet engines installed within the fuselage - making the D-36 a mixed-powerplant aircraft.

No fighter would be complete without an armament suite so the D-36 was proposed with 4 x 20mm cannons fitted to the nose assembly. An additional 20mm cannon was to be installed, aft-facing, at either engine nacelle to offer a rearward-firing function and counter the threat posed by any trailing interceptor. Interestingly, each gun mounting was to have a small degree of movement to offer fine-tuning when aiming. While the aforementioned armament was to be a standard fit and fixed in place, the D-36 was also designed with the required bomb- and rocket-carrying capability. This was to encompass 2 x 1,000lb bombs along with 8 x 5" (127mm) High-Velocity Aircraft Rockets (HVARs).

The Bell D-36 proposal was passed on by authorities due to issues centering on the complexity of the conjoined engine arrangement as well as what was deemed below average vision out-of-the-cockpit. There were also concerns about the basic design as it stood and its general acceptance of ejection seats for the crew which would have required a redrawing of the forward section. The gun armament in the nose was also thought to have blinded the crew when firing in the dark of night. Perceived control characteristics and estimated performance were the high marks of the submission but not enough to warrant a development contract - in fact authorities found the other competing designs bested Bell's design in several major performance categories. Of the nine proposals submitted, Bell's ended in sixth place.

The winning bid, presented by Northrop as the "N-24", would go on to become the Cold War-era warrior F-89 "Scorpion" jet-powered fighter in operational service. The Curtiss XP-87 "Blackhawk" jet-powered interceptor (detailed elsewhere on this site) also came from the same all-weather heavy fighter requirement but was also passed on after two prototypes were completed. This ended Curtiss' involvement in fighter-making.

Performance estimates of the Bell D-36 included a maximum speed of 550 miles per hour, a service ceiling of 43,250 feet, and a range of 2,600 miles (when flying at 20,000 feet altitude). Rate-of-climb was to reach near 7,660 feet-per-minute.
Bell D-36 Specifications
National Flag Graphic
United States
Year: 1950
Type: All-Weather Heavy Fighter / Night-Fighter Aircraft Proposal
Manufacturer(s): Bell Aircraft - USA
Production: 0
Supported Mission Types
Air-to-Air
Interception
Unmanned
Ground Attack
Close-Air Support
Training
Anti-Submarine
Anti-Ship
Airborne Early Warning
MEDEVAC
Electronic Warfare
Maritime/Navy
Aerial Tanker
Utility/Transport
Passenger Industry
VIP Travel
Business Travel
Search/Rescue
Recon/Scouting
Special Forces
X-Plane/Development
Structural
Crew: 2
Length: 47.08 ft (14.35 m)
Width: 56.10 ft (17.10 m)
Height: 16.24 ft (4.95 m)
Empty Weight: 18,739 lb (8,500 kg)
MTOW: 30,005 lb (13,610 kg)


Installed Power
2 x General Electric TG-100 (T31) turboprop gas turbine engines of unknown horsepower output in wings driving three-bladed propeller blades in counter-rotating fashion; 2 x Westinghouse 24C-6 turbojet engines in fuselage.

Standard Day Performance
Maximum Speed: 550 mph (885 kph; 478 kts)
Maximum Range: 2,600 mi (4,185 km; 2,260 nm)
Service Ceiling: 43,258 ft (13,185 m; 8.19 mi)
Rate-of-Climb: 7,660 ft/min (2,335 m/min)


Armament
PROPOSED:
4 x 20mm cannons in nose assembly.
2 x 20mm cannons in engine nacelles, aft-facing (one gun per nacelle).

OPTIONAL:
2 x 1,000 lb conventional drop bombs
8 x 5" (127mm) High-Velocity Aircraft Rockets (HVARs)


Operators List
United States (not selected)

Series Model Variants
• D-36 - Bell Proposal Designation


Supported Weapon Systems
Graphical image of an aircrat automatic cannon
Graphical image of an aircraft conventional drop bomb munition