By 1942, the world was at war with the United States committed to the fight in Africa, Europe, and the Pacific. The Pacific Theater required a major investment in over-water and on-water solutions and, for the attack role, the torpedo bomber and dive bomber were king. In the decade prior, the United States Navy (USN) shifted policy and accepted designs covering torpedo and bombing roles individually. However, during the war, it was seen that a combination design able to fulfill both roles was more tactically sound against the Empire of Japan's vaunted naval fleet.
In February 9th, 1942, the USN sought a new combination design and contracted with Curtiss Aeroplace and Motor Company to fulfill the requirement. The engine of choice became the Wright R-3350 air-cooled radial driving a three-bladed propeller unit at the nose and the usual crew of two or three was reduced to just one as technical advances and wartime theory offered simplification. To cover the bombing role, an internal bomb bay was required while a single torpedo (Mk 13-2 family) could be held externally along the ventral fuselage line. Two external hardpoints were also available for drop bombs. The structure of the new aircraft would have to satisfy the rigors and stresses inherent in the dive bombing action. Standard, fixed armament centered on 4 x 20mm automatic cannons for ground strafing and an possible air-to-air action the operator might encounter. For enhanced survivability, self-sealing fuel tanks were a must.
The performance specifications included an optimal operating range of 1,000 miles fully-laden. Range could increase to 1,500 miles with the optional fuel drop tanks.
Curtiss engineers moved on a pair of designs, the first fitting a conventional arrangement involving the R-3350 radial of 2,300 horsepower mated to a single three-bladed propeller unit at the nose and another housing the experimental Pratt & Whitney (PW) XR-4360-14 "Wasp Major" super-charged, water-injected radial of 3,000 horsepower driving a pair of three-bladed propellers in a contra-rotating arrangement. The result was the project "Model 96" for the company.
USN authorities liked what they saw in the promising attacker and contracted for both to be completed, each with their respective engine installations, to be known under experimental designations "XBTC-1" (Wright engine) and "XBTC-2" (Pratt & Whitney engine). The latter differed not only in engine and prop install but also in dimensions, being larger than its sister, and incorporated a Fowler flap (Model A wing) or duplex flap (Model B wing) arrangement in the wings. Dive brakes and edge slats also were standard.
Of note is that this Curtiss / USN marriage marked the first large scale commitment by the service in attempting to satisfy a multi-role attack platform when such ventures were typically reserved for fighter types.
The company initially moved fast on the agreement and delivered mockups before the end of 1942. Not all was right, however, for the Curtiss was deep in the American war effort and - coupled to the Army need for the Pratt & Whitney radial - the program began to stall into 1943 by which point the XBTC-1 initiative was dead before the end of the year by the Navy's decision. The service did, indeed, move forward with the XBTC-2 and contracted for two prototypes.
Curtiss Aeroplane and Motor Company - USA
United States (cancelled)
Ground Attack (Bombing, Strafing)
Ability to conduct aerial bombing of ground targets by way of (but not limited to) guns, bombs, missiles, rockets, and the like.
Special-Mission: Anti-Submarine Warfare (ASW)
Equipped to search, track, and engage enemy underwater elements by way of specialized onboard equipment and weapons.
Equipped to search, track, and engage enemy surface elements through visual acquisition, radar support, and onboard weaponry.
Maritime / Navy
Land-based or shipborne capability for operating over-water in various maritime-related roles while supported by allied naval surface elements.
X-Plane (Developmental, Prototype, Technology Demonstrator)
Aircraft developed for the role of prototyping, technology demonstration, or research / data collection.
Mainplanes are designed to fold, improving storage on land and at sea.
Inherent ability of airframe to take considerable damage.
Fuselage volume includes space for internally-held weapons or special-mission equipment.
EXTENDED RANGE PERFORMANCE
Capability to travel considerable distances through onboard fuel stores.
Ability to operate over ocean in addition to surviving the special rigors of the maritime environment.
Manual process of allowing its pilot and / or crew to exit in the event of an airborne emergency.
Features partially- or wholly-enclosed crew workspaces.
Features retracting / retractable undercarriage to preserve aerodynamic efficiency.
Ability to launch / release torpedoes against ocean-going threats / targets.
39. 0 ft
(11. 90 m)
50. 0 ft
(15. 25 m)
13. 0 ft
(3. 95 m)
monoplane / low-mounted / straight
Design utilizes a single primary wing mainplane; this represent the most popular mainplane arrangement.
Mainplanes are low-mounted along the sides of the fuselage.
The planform involves use of basic, straight mainplane members.
(Structural descriptors pertain to the Curtiss XBTC-2 production variant)
1 x Pratt & Whitney R-4360 Wasp Major air-cooled radial piston engine developing 3,000 horsepower driving 2 c Three-bladed propeller units at the nose in contra-rotating arrangement.
(605 kph | 327 kts)
(305 kph | 165 kts)
Max. Speed Diff
(+300 kph | 162 kts)
(8,000 m | 5 mi)
(2,955 km | 5,473 nm)
MACH Regime (Sonic)
RANGES (MPH) Subsonic: <614mph | Transonic: 614-921 | Supersonic: 921-3836 | Hypersonic: 3836-7673 | Hi-Hypersonic: 7673-19180 | Reentry: >19030
PROPOSED:4 x 20mm automatic cannons in the wings (inboard of wing-fold hinge). Up to 2,000lb of conventional drop bombs (2 x 1,000lb bombs) in the internal bomb bay or a single torpedo held under the fuselage. Also optional provision for external bomb mountings and jettisonable fuel tanks.
(Not all ordnance types may be represented in the showcase above)
Hardpoint Mountings: 2
Note: Diagram above does not take into account inline hardpoints (mounting positions seated one-behind-the-other).
XBTC - Base Project Designation. XBTC-1 - Proposed prototype carrying the Wright R-3350 Duplex-Cyclone engine; not ordered. XBTC-2 - Prototype model fitting the Pratt & Whitney R-4360 Wasp Major air-cooled radial engine; two examples completed with Model A and Model B wing structures, respectively; First prototype scrapped, second prototype lost to accident.