<p>During the closing stages of World War l, the little-known Ordnance Engineering Corporation of Baldwin, New York, designed a single-seat fighter biplane. This proved of interest to the new US Army Air Service which had been formed on 24 May 1918. Designated by the company as the Orenco D, it was a robust-looking twin-bay biplane of all-wooden construction with the fuselage skinned with plywood, its tailskid-type landing gear including heavy Vee struts for the through-axle main landing gear. Selected powerplant was the Wright Model H, this being a licence-built version of the Hispano-Suiza 300-hp (224-kW) V-8 liquid-cooled engine, which in the case of the Orenco D was given a nose radiator installation.
</p>
<p>Only four prototypes (40107-40110) were procured from Ordnance Engineering (which failed to make any other sales and soon went out of business) and delivery of these began in January 1919. The type was given a thorough evaluation before—later in 1919—the USAAS requested US aircraft manufacturers to tender for the production of a batch of 50, the contract eventually being awarded to the Curtiss Aeroplane and Motor Company of Buffalo, New York. Only minor modifications were introduced by Curtiss, the most noticeable being a slight increase in span of the upper wing and the introduction of horn-balanced ailerons. Delivery of these aircraft (63281-63330) began in 1920 and was completed during the following year. Before delivery of the Curtiss-built Orenco Ds, the USAAS had introduced a new system of type nomenclature, pursuit aircraft with liquid-cooled engines being known as Type I and given PW designation prefixes. These designations were not applied to aircraft already delivered, although the Orenco D was listed as a Type I aircraft. Lack of documentation would suggest that it was far from successful in service and that it was soon taken out of use.
<item><hi format=bold>Powerplant:</hi> one 200-hp (220-kW) Wright H V-8 engine
<item><hi format=bold>Performance:</hi> maximum speed 139 mph (224 km/h); cruising speed 134 mph (215 km/h); climb to 1,227 ft (374 m) in one minute; service ceiling 12,468 ft (3,800 m); range 342 miles (550 km)
<item><hi format=bold>Weights:</hi> empty 1,907 lb (865 kg); maximum take-off 2,820 lb (1,279 kg)
<item><hi format=bold>Dimensions:</hi> span 33 ft (10.06 m); length 21 ft 6 in (6.54 m); wing area 273 sq ft (25.36 m<su>2</su>)
<item><hi format=bold>Armament:</hi> two fixed synchronized 0.3-in (7.62-mm) Browning machine guns
