The road to the American classic war-winning Republic P-47 "Thunderbolt" of World War 2 went through various iterations under the leadership of engineer Alexander Kartveli. In 1937 the United States Army Air Corps (USAAC) took into service the Seversky P-35 which was authored by Kartveli under the Seversky brand label (Seversky was reorganized in 1939 to become "Republic"). The P-35 was notable for it becoming the first American-made single-seat, single-engine monoplane fighter to feature all-metal construction, a fully-enclosed cockpit, and a completely retractable undercarriage. From this form the P-43 "Lancer" was eventually developed and arrived in 1941 to be used by the air services of the United States, China and Australia with production reaching 272 units before the end.
Even before the P-43 came to fruition, there was a stop at another Republic fighter offering - the P-44 "Rocket". The fighter was developed to a new U. S. Army requirement for an interceptor / pursuit type capable of speeds in the upper 300mph, lower 420mph range while flying under 20,000 feet of altitude. Republic beat out other submissions with their "AP-4J" which promised to fulfill the required specs.
Design work was, again, headed by Kartveli and drive power would stem from a single Pratt & Whitney R-2180-1 "Twin Hornet" engine of 1,400 horsepower fitted to the nose. A monoplane wing arrangement was, of course, in play and showcased rounded wingtips. The fuselage was well-contoured with the radial piston engine air-cooled and shrouded by a very tight cowling. A traditional single-finned tail unit was positioned to the rear in the usual way. The "tail-dragger" undercarriage was completely retractable. The cockpit, with its raised fuselage spine, was heavily framed and seated a single operator at midships. Armament was to be wholly machine gun-based: a mix of 2 x 0.50 caliber heavy machine guns paired with 4 x 0.30 caliber medium machine guns (a common arrangement of pre-war/early-war American fighters).
The AP-4J was estimated with a maximum speed of around 385 miles per hour and the Army thought enough of the Republic initiative to award a contract to the company for 80 aircraft on September 13th, 1939. Rather notable was the lack of any working, flyable prototypes to ensure a sound design. By this time, the war in Europe had just begun (September 1st) and reports from the front became critical to observers stateside and it was quickly realized that the modern mounts of Europe outclassed those being offered by the Americans.
The AP-4J was evolved into the AP-4L which was to install the Pratt & Whitney R-2800-7 series air-cooled radial of 2,000 horsepower. Additional internal fuel stores would be provided to help increase range. Cockpit armoring was now an essential quality of fighting warplanes as were self-sealing fuel tanks so these too found their way into the revised P-44 design - which was now ordered by the Army as the P-44-2 on July 19th, 1940. The initial contract called for 225 fighters to the newer standard and this was increased to 827 on September 9th of that same year. Even despite the added weight, Republic engineers were optimistically hopeful that their new fighter would hit the 422mph maximum speed envelope.
However, as soon as it arrived on the drawing boards, the P-44 Rocket was made more or less obsolete by events half-a-world-away. Fortunately for Republic it had also been hard at work at developing another fighter in the "AP-10" which also caught the Army's eye back in November of 1939 - this aircraft becoming the prototype XP-47 before being finalized in service as the classic P-47 Thunderbolt. With the XP-47 proving itself the more promising venture, the P-44 project was ended on September 13th, 1940 with no physical prototype to show for the years-long effort - such was the military aircraft design business. To keep Republic production lines open until P-47 manufacture could be brought up to speed, the P-44 contract was simply converted by authorities to purchase more P-43 Lancer fighters for the U.S. Army and its ally in China.
(OPERATORS list includes past, present, and future operators when applicable)
✓Air-to-Air Combat, Fighter
General ability to actively engage other aircraft of similar form and function, typically through guns, missiles, and/or aerial rockets.
Ability to intercept inbound aerial threats by way of high-performance, typically speed and rate-of-climb.
✓X-Plane (Developmental, Prototype, Technology Demonstrator)
Aircraft developed for the role of prototyping, technology demonstration, or research / data collection.
28.7 ft (8.75 m)
36.1 ft (11.00 m)
14.3 ft (4.35 m)
5,986 lb (2,715 kg)
8,598 lb (3,900 kg)
+2,612 lb (+1,185 kg)
(Showcased structural values pertain to the Republic P-44-2 production variant)
1 x Pratt & Whitney R-2800-7 air-cooled radial piston engine developing 2,000 horsepower and driving a three-bladed propeller unit at the nose.
2 x 0.50 caliber heavy machine guns.
4 x 0.30 caliber medium machine guns.
(Not all ordnance types may be represented in the showcase above)
Hardpoint Mountings: 0
AP-4J - Initial project submission; fitted with Pratt & Whitney R-2180-1 Twin Hornet radial piston engine of 1,400 horsepower.
AP-4L - Revised project submission; fitted with PW R-2800-7 radial engine of 2,000 horsepower; self-sealing fuel tanks; increased fuel load; cockpit armoring; additional machine guns.
P-44 - U.S. Army designation for production quality fighter.
P-44-2 - Revised Army model based in the AP-4L project submission.
Values are derrived from a variety of categories related to the design, overall function, and historical influence of this aircraft in aviation history.
The overall rating takes into account over 60 individual factors related to this aircraft entry.
Rating is out of a possible 100 points.
Relative Maximum Speed
This entry's maximum listed speed (373mph).
Graph average of 300 miles-per-hour.
Republic P-44-2 operational range when compared to distances between major cities (in KM).
Max Altitude Visualization
The 3 qualities we look at for a balanced aircraft design are altitude, speed, and range.
Aviation Era Span
Showcasing era cross-over of this aircraft design.
Ribbon graphics not necessarily indicative of actual historical campaign ribbons. Ribbons are clickable to their respective aerial campaigns / operations / aviation periods.
The "Military Factory" name and MilitaryFactory.com logo are registered ® U.S. trademarks protected by all applicable domestic and international intellectual property laws. All written content, illustrations, and photography are unique to this website (unless where indicated) and not for reuse/reproduction in any form. Material presented throughout this website is for historical and entertainment value only and should not to be construed as usable for hardware restoration, maintenance, or general operation. We do not sell any of the items showcased on this site. Please direct all other inquiries to militaryfactory AT gmail.com.
Part of a network of sites that includes GlobalFirepower, a data-driven property used in ranking the top military powers of the world, WDMMA.org, the World Directory of Modern Military Aircraft, and SR71blackbird.org, detailing the history of the world's most iconic spyplane.