The Morane-Saulnier MoS-121, also known as the Morane-Saulnier MS.121 was a French fighter prototype of the 1920s. It was Morane-Saulnier's first fighter design after World War I.

MoS 121
Role	Fighter Type of aircraft
National origin	France
Manufacturer	Morane-Saulnier
First flight	1927
Number built	1

Development

As a direct result of concern over the escalating cost of fighter manufacture, the French government and air force instituted a program for chasseurs légers or 'light fighters' in 1926. This was unofficially known as the 'Jockey' program, and it envisaged the use of moderate guns, minimal equipment and small amounts of ammunition. Emphasis was placed on climb rate, endurance and a ceiling (high for the time) of 8000 metres. To meet this requirement, Morane-Saulnier designed the MoS-121, renamed the MS 121 in 1927, as a single-seat parasol monoplane of mixed construction.

Operational history

After flying for the first time in mid-1927, it proved underpowered and incapable of climbing easily and was discarded in favour of the Morane-Saulnier MS.221.

Specifications (MoS-121)

Data from Jane's all the World's Aircraft 1928,[1] The Complete Book of Fighters[2]

General characteristics

• Crew: 1
• Length: 6.717 m (22 ft 0 in)
• Wingspan: 9.8 m (32 ft 2 in)
• Height: 2.885 m (9 ft 6 in)
• Wing area: 16 m² (170 sq ft)
• Empty weight: 990 kg (2,183 lb)
• Gross weight: 1,250 kg (2,756 lb)
• Powerplant: 1 × Hispano-Suiza 12Jb , 347 kW (465 hp)
• Propellers: 2-bladed wooden fixed pitch propeller

Performance

• Maximum speed: 253 km/h (157 mph, 137 kn) at 1,000 m (3,300 ft)
  

250 km/h (160 mph; 130 kn) at 2,500 m (8,200 ft)

246 km/h (153 mph; 133 kn) at 3,500 m (11,500 ft)

• Endurance: 1.5 hours at full throttle
• Service ceiling: 8,700 m (28,500 ft)
• Time to altitude: 1,500 m (4,900 ft) in 3 minutes 44 seconds
  

3,500 m (11,500 ft) in 9 minutes 19 seconds

4,500 m (14,800 ft) in 13 minutes 11 seconds

6,500 m (21,300 ft) in 25 minutes 25 seconds

7,500 m (24,600 ft) in 36 minutes 5 seconds

• Wing loading: 78 kg/m² (16 lb/sq ft)
• Power/mass: 0.2694 kW/kg (0.1639 hp/lb)

Armament

• Guns: 2x fixed forward firing 7.7 mm (0.303 in) Vickers machine-guns with 300 rpg

References

Wikimedia Commons has media related to Morane-Saulnier MS.121.

Further reading

• Lacaze, Henri & Lherbert, Claude (2013). Morane Saulnier: ses avions, ses projets [Morane Saulnier: Their Aircraft and Projects] (in French). Outreau, France: Lela Presse. ISBN 978-2-914017-70-1.