Curtiss XPW-8B / F6C / P-1 Hawk / P-2 Hawk / AT-4 / AT-5


Curtiss P1

With its origins in the Model L-18-1 (which stemmed the PW-8 US Army production fighters), the Curtiss model 34 / XPW-8A became the P-1 prototype. A biplane single-engine, single-seat fighter with fixed landing gears, tapered-wings, wheel brakes and more powerful engines, produced a large number of variants for the Curtiss company.

Armed with an array of .303 caliber machine guns, the aircraft had a flight ceiling of over 20,000 feet and speeds in excess of 150 miles per hour.

On 7 March 1925, Curtiss was awarded a contract for 15 production examples of the model 34A XPW-8B as the P-1, this being the first fighter to which the company assigned the name Hawk. Externally similar to the XPW-8B, the P-1 was of mixed construction with wooden wings and steel-tube fuselage with fabric skinning, and was powered by a 435hp Curtiss V-1150-1 12-cylinder water-cooled engine. The first aircraft became the XP-17, and the final five aircraft were completed as model 34B P-2s, three of these later being converted to P-1A standards.

They were delivered to the 27th and 94th Pursuit Squad-rons from August 1925, with 435-hp Curtiss V-1150-1 12-cylinder liquid-cooled V-type engines.


Curtiss P-1A 1926

Follow-on contracts were placed on 9 September 1925 for Model 34G 25 P-1As (which had a 7.62cm longer fuselage), revised engine cowling and slightly heavier all‑up weight. They were delivered from April 1926, they served with the 17th, 27th and 94th Pursuit Squadrons. One each was used for XP-6A, XAT-4A, XP-3A, AND XP-22.

Next production version was the P-1B (again an order for 25, in August 1926), powered by a 435-hp V-1150-3 engine, which had larger main wheels and a modified radiator.

The 33 P-1Cs, ordered in October 1928 and delivered by April 1929, also utilized the V-1150-3 engine and were fitted with wheel brakes.

All these sub-types carried an armament of two 7.62mm guns.

In the meantime, the USAAC had ordered advanced trainers utilising the same airframe. These comprising 35 AT-4s (180hp Wright V-720), five AT-5s and 31 AT-5As (220hp Wright R-790), and, in 1929, these were re-engined with the V-1150-3, all 35 AT-4s becoming P-1Ds and four AT-5s and 24 AT-5As becoming P-1Es and P-1Fs respectively. One other P-1F resulted from reconverting the XP-21, which had previously been a P-3A.

These conversions were essentially similar to the P-1B apart from having only one gun. Four P-1s were supplied to Bolivia, one P-1A went to Japan, and eight P-1As and eight P-1Bs were supplied to Chile.

The P‑2s (model 34B) were the last five machines from the original P‑1 contract, but powered by 505‑hp V‑1400 engines; three of these P‑2s were converted later to P‑1A standard. One became the XP-6.


The Curtiss F6C Hawk series of aircraft was the US Navy/Marine model of the US Army's P-1 Hawk series. The US Navy began fielding the P-1 it as a carrier-based aircraft while the US Marines operated it as a land-based fighter.

In March 1925, the US Navy ordered nine P-1s with provision for float operation as (Curtiss Model 34) F6Cs (the F5C designation was not assigned, to avoid confusion with the F-5 flying boat). Five of these were delivered as Model 34C F6C-1s with provision for float undercarriage, but no arrester gear, and four (with arrester hooks) as Model 34D F6C-2s. These had 400‑hp Curtiss V­1150 similar power plant to the USAAC's P-1 and the standard two 0.30‑in (7.62‑mm) gun armament. Two of the F6C-1s were later converted to -2 standard. The last four became F6C-2s. In 1927, 35 additional aircraft were ordered, these using the P-1A airframe and being designated F6C-3. Two F6C-1s were converted to -3 standard and one F6C-3 was fitted with a Pratt & Whitney R-1340 radial as the XF6C-3.
A batch of 35 incorporating these improve­ments was ordered in 1927; these, plus two others converted from F6C‑1s, entered with the USN and USMC in 1928 as the Model 34E F6C‑3. One became the F6C-6 racer and later became the XF6C-6 monoplane. A twin‑float F6C‑3 won the Curtiss Marine Trophy race in 1930 at a speed of 264.1 km/h (164.1 mph).

Two F6C-2s (the balance of the F6C-1 contract), fitted with arrester hooks and strengthened landing gear, were used for deck trials.


The US Navy had decided, by 1927, to standardise on air-cooled radial engines, which were more easily maintained at sea than liquid-cooled inline engines. After trials with a Pratt & Whitney R-1340- engined F6C-3, a production contract was placed for 31 fighters powered by this 410hp radial as F6C-4s (model 34H). The first of these aircraft, which was retained for test purposes was assigned the temporary designation XF6C-7, and deliveries commenced in February 1927. Possessing the same twin-gun armament as its predecessors, the F6C-4 proved more manoeuvrable than the V-1150- powered models, but was becoming obsolescent by the time that it was delivered. The F6C-4 were issued to one squadron only (in the USS Langley) for operational use until 1930; others were put into service as advanced trainers.

A total of 75 of the F6C series Hawks were produced for the US Navy.

Experimental F6C models were:
XF6C-5 (first F6C-1 fitted with a 525hp Pratt & Whitney R-1690 Hornet)
XF6C-6 (an F6C-3 converted to parasol monoplane configuration for the 1930 Thompson Trophy race)
F6C-6 (an F6C-3 modified for 1929 air races and returned to -3 standard)
XF6C-7 (an F6C-4 with an inverted air-cooled Ranger SGV-770 engine).

Curtiss P-1
Engine: 435hp Curtiss V-1150-1 12-cylinder water-cooled

Curtiss P-1B
Take-off weight: 1 330 kg
Empty weight: 955 kg / 2105 lb
Wingspan: 9.63 m / 31 ft 7 in
Length: 6.91 m / 22 ft 8 in
Height: 2.72 m / 8 ft 11 in
Wing area: 23.23 sq.m / 250.05 sq ft
Range: 966 km / 600 miles
Maximum speed: 253 km/h (157 mph).

Curtiss P-2
Engine: 505-hp V-1400 engines

Curtiss F6C-3 Hawk
Engine: 1 x Curtiss D.12 Conquerer water-cooled inline, 400hp.
Length: 22.83ft (6.96m)
Wingspan: 31.59ft (9.63m)
Wing area: 23.41 sq.m /251.98 sq ft
Height: 3.25 m / 10 ft 8 in
Maximum Speed: 154mph (248kmh; 134kts)
Maximum Range: 351miles (565km)
Service Ceiling: 20,299ft (6,187m; 3.8miles)
Armament: 2 x .303 inch machine guns
Accommodation: 1
Empty Weight: 2,161lbs (980kg)
Maximum Take-Off Weight: 3,349lbs (1,519kg)

Curtiss F6C-4
Span: 9.60 m (31 ft 6 in)
Length: 6.86 m (22 ft 6 in)
Gross weight: 1263 kg (2784 lb)
Maximum speed: 249 km/h (155 mph).



Curtiss F6C-4



Curtiss P-1 Hawk