MS 733 Alcyon

The Morane-Saulnier MS.733 Alcyon (Kingfisher) is a two- or three-seat basic training monoplane built in France by Morane-Saulnier. It entered French military service in the early 1950s as a replacement for pre-war Stampe SV.4 biplanes, and is known for its unusually complete instrument-flight equipment for a piston trainer and for the armed MS.733A counter-insurgency conversion used in Algeria.

Development

The prototype MS.730 first flew on 11 August 1949, powered by a 180 hp (130 kW) Mathis 8G.20 inverted V8. The engine was replaced with a war-surplus 240 hp (180 kW) Argus As 10 and the aircraft flew again in November 1949 as the MS.731. Two further prototypes designated MS.732 flew in 1951 with retractable main wheels in place of the original fixed gear. The production MS.733 followed, with five pre-production and 200 production aircraft built. Deliveries comprised 145 to the French Air Force, 40 to the French Navy and 15 to the Cambodian Air Force.

Design

The Alcyon is a low-wing cantilever monoplane with tailwheel landing gear, fixed on the MS.730/731 prototypes and with retractable main units from the MS.732 onward. The MS.733 is powered by a Potez 6D inverted inline piston engine of 179 kW (240 hp), giving a maximum speed of 260 km/h, a cruise of 230 km/h, a range of 920 km, an endurance of 4 hours 40 minutes and a service ceiling of 4,800 m. Length is 9.32 m, wingspan 11.28 m, wing area 21.90 m², empty weight 1,260 kg and gross weight 1,670 kg. Avionics fit included two VOR-ILS sets, one ADF, two VHF radios, a radar altimeter, an attitude indicator and a directional gyroscope, permitting full IFR work.

Armament

Training aircraft were unarmed and had no hardpoints. Seventy French Air Force machines were fitted with machine guns for gunnery training, and some were converted to MS.733A standard with a SFOM 83 reflector sight suspended from the cockpit roof and two 7.5 mm MAC 1934/M39 machine guns in the wings with 500 rounds each. Two underwing hardpoints were added, typically carrying paired Matra Type 14 rocket rails with four stacked SERAM 28 kg T10 heavy rockets, plus a smaller station between the rails rated for a 50 kg bomb.

Operational History

MS.733A aircraft served in the counter-insurgency role in Algeria from 1955 to 1959, when they were replaced by the T-28S Fennec. After the Algerian War, surviving French Air Force aircraft were either sold or converted back to MS.733 trainers, with several going to the Moroccan Air Force for COIN duties. French Navy aircraft operated exclusively from land bases and were not fitted with carrier landing equipment. Cambodia received 15 aircraft for training and COIN work, and Air France bought five civilianised MS.733s as single-engine trainers; the type was also used by civilian flying schools for navigation training as a cheaper alternative to twin-engine aircraft. Several Alcyons have since been restored to flying condition in France by private owners.

Variants

• MS.730: Prototype with a 180 hp (134 kW) Mathis 8G.20 engine, one built and later re-engined.
• MS.731: The MS.730 prototype re-engined with a 240 hp (179 kW) Argus As 10.
• MS.732: Two prototypes with a 200 hp (149 kW) Salmson 8.AS.02 and retractable landing gear.
• MS.733: Production variant with a 240 hp (179 kW) Potez 6D 02; five pre-production and 200 production aircraft built.
• MS.733A: Gunnery trainers modified for the counter-insurgency role, in service 1955–1959.