<p>The Mahoney-Ryan Aircraft Corporation, in 1927, was responsible for the construction of the Ryan NYP monoplane 'Spirit of St Louis' in which Charles Lindbergh made the first nonstop solo flight across the North Atlantic during 20/21 May 1927. A temporary boom in sales followed this achievement, bringing a merger with Detroit Aircraft Corporation in May 1929, but this company did not survive the depression of 1930-31.
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<p>Sensing a new demand for lightplanes, T. Claude Ryan founded the Ryan Aeronautical Company in 1933-34, using as his key to the market a two-seat light monoplane which had the designation S-T. Production of this began in 1934, and it was available in three versions with engines of 95-150 hp (71-112 kW) as S-T, S-T-A or S-T-A Special. When the US Army Air Corps began to show interest in the procurement of new primary trainers, a single example of the Ryan S-T-A was acquired for evaluation under the designation XPT-16. When delivered in 1939, this represented something of an evolutionary step for the USAAC, for it was the first primary training monoplane to be acquired: all previous USAAC primary trainers had all been biplanes.
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<p>Early evaluation resulted in considerable interest in the type, and very soon an additional 15 YPT-16s were procured so that a wider evaluation program could be completed more rapidly. These differed from the XPT-16 only by the addition of an electric starter. Both of these initial versions were powered by the 125-hp (93-kW) Menasco L-365-1 inline engine, although the XPT-16 was re-engined with a 125-hp R-440-1 engine to become the XPT-16A.
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<p>An order for 40 production aircraft followed in 1940 under the designation PT-20 and these, delivered in 1941, were generally similar to the YPT-16s except for minor structural changes such as wider cockpits and strengthened airframes.
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<p>During 1941 the US Army decided that the five-cylinder Kinner R-440 radial engine offered better performance than the Menasco inline, and the 100 PT-21s ordered in 1941 were powered by the 132-hp (98-kW) Kinner R-440-3 engine. The installation of this engine in a streamlined nose fairing, with its five cylinders projecting through the fairing and left uncowled, meant that the PT-21, and subsequent Kinner-engined variants, were easily identified. Their entry into service showed the superiority of this airframe/engine combination, with the result that 13 of the YPT-16s and 27 of the PT-20s were re-engined with 132-hp (98-kW) Kinner R-440-1 engines, and were redesignated PT-16A and PT-20A, respectively. Three PT-20s delivered with civil (as opposed to military) versions of the Menasco engine, the D-4, were designated PT-20B.
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<p>With the rapid expansion of aircrew training during 1941, Ryan received a contract for 1,023 examples of what was to be the final and most extensively built version, the PT-22 Recruit. This introduced several changes, including deletion of the wheel spats and main landing gear unit fairings which had proved troublesome with aircraft which were making far more take-offs and landings per day than had been envisaged during original design, and by installation of a 160-hp (119-kW) Kinner R-540-1 engine; in other respects these aircraft were similar to the PT-21. 250 aircraft re-engined with the R-540-3 engine received the PT-22C designation.
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<p>Ryan also built a number of S-Ts for export, and included among these orders was one from the Netherlands for the supply of 25 S-T-3s (basically the same structurally and with the same powerplant as the USAAC PT-22s). By the time these were ready for delivery, the Netherlands had already been overrun by German forces and, with the designation PT-22A, they were acquired by the US Army. Used mainly at civilian-operated flying training schools throughout the US, the Ryan trainers gave valuable service before their retirement towards the end of World War II.
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<p>This demand for training aircraft was not exclusive to the USAAC, for the US Navy had initiated a similar expansion of its training program. Following US Army evaluation of this trainer, the US Navy also ordered 100 examples of the Ryan S-T-3 version with Kinner R-440-3 engines on 19 August 1940, these being designated NR-1 Recruit and remaining in service until mid-1944.
<item><hi format=bold>Performance:</hi> maximum speed 131 mph (211 km/h); cruising speed 123 mph (198 km/h); service ceiling 15,500 ft (4,725 m); range 352 miles (566 km)
<item><hi format=bold>Weights:</hi> empty 1,313 lb (596 kg); maximum take-off 1,860 lb (844 kg)
<item><hi format=bold>Dimensions:</hi> span 30 ft 1 in (9.17 m); length 22 ft 5 in (6.83 m); height 6 ft 10 in (2.08 m); wing area 134.25 sq ft (12.47 m<su>2</su>)
