Country of origin:

United States of America

Description:

Two-seat military trainer

Power Plant:

One 112 kw (150 hp) Menasco C4S six-cylinder in-line air-cooled engine; or

one 108 kw (145 hp) de Havilland Gipsy 1 four-cylinder in-line air-cooled engine

Specifications:

History:

In 1934 Tubal Claude Ryan created the Ryan Aeronautical Corporation in a location similar to where the old Ryan Aircraft Company had built its designs. After the success of the Model ST-A development continued and lead to orders for military service. This model also was a low-wing wire-braced monoplane, the outer wing structure having two solid spruce spars, stamped aluminium alloy ribs, aluminium alloy leading edge back to the front spar, and fabric covering. Wing flaps extended over half the wingspan. The fuselage was of metal monocoque construction, and the tail unit was of the normal monoplane type, with metal framework and fabric covering.

Subsequently the type was built for civil and military operators in a number of variants, including the STM-1 with the Menasco C4S engine which provided 112 kw (150 hp) at 2,260 rpm; and the STM-2 which, after modification to meet US Army Air Corps requirements, entered service as the PT-20. Examples were supplied to South American Air Forces, Mexico ordering six in 1937, Honduras obtaining single-seat armed models in 1938, and Guatemala obtaining unarmed and armed variants, the latter being fitted with two 7.62 mm (0.30 in) Colt machine guns on the forward fuselage and a 7.62 mm (0.30 in) Lewis machine gun on each wing. China obtained 50 examples in 1939, these being fitted with a single fuselage-mounted machine gun.

In 1938 Lake Boga in northern Victoria was being considered as the site of a potential flying boat base and local representations were made to the Federal Government for the construction of such a base, as well as a base for land based aircraft at Swan Hill. Nothing happened for some time but in 1942 the concept was raised again, the idea to build a secret base being considered, a Department of Air minute referring to a flying boat repair depot at Lake Boga. To be located there was a RAAF Seaplane Training Flight which would operate four Supermarine Seagull Vs with a further two available; three Consolidated PBY-5 Catalinas with a spare, and a Netherlands East Indies Air Force Seaplane Training Flight, the latter to have two Catalinas, five Dornier Do.24Ks and 17 Ryan STM seaplanes, and a further five training aircraft.

As is well known, the base was set up as a flying boat repair depot for the RAAF and other country units operating in and around Australia but by the time the base was set up any chance of the NEI unit being attached to the base had dissipated. The two Catalinas, Dornier DO.24Ks and Ryan STMs had all been transferred to the RAAF but it is not believed any of the Ryans ever operated on floats from Lake Boga, although at least three are known to have operated at Rose Bay and Rathmines, NSW for a period on pilot training duties.

The surviving Ryan STMs and STM-S2s (floatplanes) from the NEI Air Force were received by the RAAF and allotted the serials A50-1 to A50-34. These aircraft were destined for the Netherlands East Indies Air Force as landplane and floatplane trainers, being shipped from Los Angeles, California on board the MS Java. Most were delivered to the East Indies and entered service but, in the face of the Japanese onslaught in the Pacific, they were only in service a short time. Twelve American instructors were sent to Surabaya to train crews in 1940, these aircraft being fitted with floats, and during air raids two of the floatplanes were attacked by Zeros. Two were lost and after the first air raid they were flown to safety for a time.

However, the situation became desperate and most of the survivors were dismantled and placed on ships for evacuation to Australia, 36 being known to have been loaded on the ‘MS Tjinegara’ in February 1942. A couple which were abandoned were captured and operated by Japanese crews. Some 48 are known to have been built for the KNMLD, serials S-1 to S-34 being landplanes and S-35 and S-36 as seaplanes, although there were more than two which operated as floatplanes. Five are known to have been lost in Dutch service, and two were lost to Japanese action. Records indicate 41 came to Australia and of these 34 received RAAF serials, being refurbished and operated as trainers. After overhaul and testing by Qantas, 28 were delivered to the RAAF and a further six were overhauled by ANA at Mascot, NSW from August 1942. It would seem those not allotted RAAF serials were used for spare parts. A couple of these latter aircraft were available for, and were transferred to, the civil aircraft register after the war.

A50-1 (c/n 447 – ex S-11) was received by the RAAF on 21 July 1942 and the last A50-34 (c/n 490 – ex S-54) on 27 August that year. Most were operated as landplanes, with a few of the floatplanes converted to a land undercarriage. They spent the war years in the training role, being used by RAAF BAG, WAGS and OAS units, whilst others were flown on light transport missions with Nos 1, 2 and 3 Communications Units. At least three (S-53, S-54 and S-55) are known to have remained on floats for a period and operated in the training role at RAAF Rathmines, NSW. One was photographed at Rose Bay at the Qantas base. After being withdrawn from service they were stored at RAAF Evans Head, NSW where a number were damaged by a hurricane on 9 April 1945. At least 20 were stored in the hangar when the storm blew in the doors.

In December 1945 there were some 22 examples at No 2 ADs Care and Maintenance Unit at Evans Head and tenders were called for their disposal, these being obtained by Brown & Dureau Ltd. Many were converted to civil standard and a number of registrations allotted, some 20 appearing on the Australian civil register. These include: VH-AHF (c/n 450 – ex A50-7, S-14); VH-AGY [ntu] (c/n 452 – ex S-16) exported to Hong Kong as VR-HDY, later LN-TVF; VH-AGU/WEB (c/n 454 – ex A50-27, S-18) which crashed at Taree, NSW on 6 April 1961; VH-BBJ/-BXN/-RUM (c/n 457 – ex A50-30, S-21), exported to the US in March 1965 as N8146; VH-AGV (c/n 458 – ex A50-17, S-22) exported to the US in 1969 as N17343; VH-AGD (c/n 459 – ex A50-11, ex S-23) which crashed at Mildura, VIC on 15 October 1967, later becoming VH-AWG and surviving; and VH-ARR/-BNG/-RAF (c/n 464 – ex A50-4, S-28) which crashed at Broken Hill, NSW on 8 June 1952.

It is interesting to note, firstly, that three Ryans have been allotted the registration VH-AGR, these being c/n 466, 475 and 483. VH-AGW (c/n 465 – ex A50-22, S-29) was in 1969 fitted with a 112 kw (150 hp) Lycoming O-360A four-cylinder engine but in later years was converted back to its Menasco engine. VH-AGR³ [ntu] (c/n 466 – ex A50-18, S-30) was exported in 1981 as N2617W, later becoming N466WA in the United States. VH-ARS/-RAE (c/n 467 – ex A50-2, S-31) crashed at Clifton, QLD on 13 February 1970 and is undergoing restoration. VH-AHD (c/n 469 – ex A50-34, S-33) later became VH-AED, its old registration VH-AHD again becoming available in October 2006 and the registration being changed.

VH-DBD (c/n 471 – ex A50-23, S-35) was owned by Donald Kendell, founder of Kendell Airlines. It was extensively damaged in an accident in Queensland in May 2006 and has been rebuilt. VH-AGQ (c/n 473 – ex A50-1, S-37) crashed at Mullumbimby, NSW on 31 January 1949. VH-AHE (c/n 474 – ex S-38) was withdrawn from service in 1956. VH-AGR² (c/n 475 – ex A50-9, S-39) was rebuilt using parts from c/n 483, which had crashed at Bankstown, NSW in February 1951. VH-AGZ (c/n 476 –ex A50-31, S-40) was exported to the United States where it became N288Y. VH-AHA (c/n 481 – ex A50-32, S-45) operated from November 1947 until withdrawn from operation in August 1951. VH-CXR (c/n 482 – ex S-46) crashed at Wyndham, WA on 20 July 1985. VH-AGR¹ (c/n 483 – ex A50-5, S-47) crashed at Bankstown, NSW on 13 February 1951.

VH-AGX [ntu] (c/n 490 – ex A50-26, S-54) was exported to Hong Kong as VR-HDM. VH-AHC (c/n 492 – ex A50-29, S-56) after some restoration at Bankstown, NSW was exported to New Zealand where the restoration was completed, the aircraft becoming ZK-STM in 2013. Later the registration was changed to ZK-ABC. VH-AGB (c/n 493 – ex A50-6, S-57) crashed at Queen’s Park, Geelong, VIC on 25 August 1946. VH-AHG (c/n 494 – ex A50-3, S-56) was exported as VR-HDK, later becoming PI-C324. A couple were re-engined with de Havilland Gipsy Major engines. As noted, a number were lost in accidents over the years, and a couple exported, but half a dozen or so survive.

Another STM noted above (c/n 489 – ex VH-AGS, A50-13, S-53) was operated for a period in New Zealand as ZK-BEM. After withdrawal from service in July 1967 it was donated to the MOTAT Museum in Auckland. It was eventually obtained by the New Zealand Warbird Association on loan and was restored to airworthiness in 1998, becoming ZK-BEM again but now fitted with a 93 kw (125 hp) Menasco L-365-1 Pirate engine. This engine was found to be unreliable and in 2012 was replaced by a LOM Prague M337AK in-line engine from the Czech Republic, this unit providing more power but being smaller and lighter.

In recent years at Tyabb, VIC work has progressed on the restoration of further Ryan airframes. Graham Hosking obtained a collection of Ryan ST-A and STM aircraft from the United States, including a number of incomplete airframes, engines and extensive spare parts. The first aircraft completed has been configured in the markings of an ex-Fuerza Aerea Hondurena (Honduran Air Force) aircraft. In June an STM-1 (c/n 302) was registered to its owner as VH-RYS at Morwell, VIC, the STM-1 differing from the STM-2, the model mainly used in Australia, in not having an external longeron under the cockpit.  About eight examples of the ST series are known to survive in Australia but not all are airworthy.