The Bloch MB.150 was a French low-wing, all-metal monoplane fighter aircraft with retractable landing gear and enclosed cockpit developed by Société des Avions Marcel Bloch as a contender in the 1934 French air ministry competition for a new fighter design.
Although the competition was won by the Morane-Saulnier M.S.406 prototype, development proceeded culminating in the first attempted flight of the MB.150.01 prototype in 1936. Unfortunately, the aircraft proved unable to leave the ground. With modifications consisting of a strengthened wing of greater area, revised landing gear, and installation of a 701 kW (940 hp) Gnome-Rhone 14N-0 radial engine with a three-blade constant speed propeller, the MB.150 finally flew in October 1937.
Bloch MB.150-155 muodostui sarjasta ranskalaisia hävittäjälentokoneita ennen toista maailmansotaa sekä sen kestäessä.
Näistä ei MB.150 tullut tuotantoon, sen sijaan MB.152 osoittautui olevan kelvollinen hävittäjäkone. Itse asiassa sarjan viimeisin malli oli MB.157, josta valmistui vain pelkkä prototyyppi. Tämän tyypin koneita valmistettiin ennen natsi-Saksan hyökkäystä vuonna 1940 niin vähän: malleja MB.151 sekä MB.152 yhteensä 140 kappaletta, ettei sillä suuren suurta sotilaallista merkitystä enää ollut.
Bloch-hävittäjät olivat Ranskan ilmavoimien ehdottomana vähemmistönä toisiin hävittäjätyyppeihin nähden, pois lukien Dewoitine D.520. Moottori oli Gnome-Rhônen valmistama kaksirivinen tähtimoottori, ja siivet noudattivat trapetsimuotoa.
Osa modifioinnista, eli tämän konetyypin tuotannollisesta kehityksestä, liittyi amerikkalaisvalmisteisten (lähinnä Pratt & Whitneyn TwinWasp) moottorien suunniteltuun käyttöön. Ne olivat ranskalaisia kevyempiä sekä tehokkaampia, mutta niiden läpimitta oli myös suurempi.
Tyyppiä MB.155 käytti Ranskan Vichyn hallitus, ja tämä oli koko sarjan taistelukykyisin hävittäjäkone. Se oli varhaisia edeltäjiään voimakkaampi – 1 060 hevosvoiman Gnome-Rhône 14N-tähtimoottorillaan ja muita aerodynaamisempi. Sitä muokattiin ja vahvistettiin muun muassa panssarointia lisäämällä, tähän mennessä Ranska oli tosin jo ehtinyt hävitä sodan Saksalle.
Nämä tyypit suunnitteli ranskanjuutalainen Marcel Bloch, joka vaihtoi nimensä myöhemmin D'Assaultiksi (suom. hyökkäys).
Handed over to the Centre d'Essais du Materiel Aerien (CEMA) for service trials, its performance proved sufficiently interesting to warrant further development. This brought, at the very beginning of 1938, a small increase in wing span and installation of a 14N-7 engine. When trials were completed in late spring 1938, SNCASO was awarded an order for a pre-production batch of 25 of these aircraft.
No such production of the MB-150.01 occurred, the aircraft being totally unsuitable for mass production. Redesign would lead to the MB.151.01 and MB.152.01 prototypes, developed and produced in parallel. By the outbreak of World War II, some 120 had reached the Armée de l'Air, but few of them were flyable, most missing their gunsights and propellers.
The MB.153 and MB.154 were intended as testbeds for American engines, but only the former flew, and when it crashed, a few days later, damaged beyond repair, pursuit of these alternatives also ceased. Instead, attention shifted to extending the range of the MB.152. This was achieved by moving the cockpit aft in order to make room for a new fuel tank. Other modifications included a slightly broader wing and revised aerodynamics around the cowling.
Length: 9.1 m (29 ft 10 in)
Wingspan: 10.54 m (34 ft 7 in)
Height: 3.03 m (9 ft 11 in)
Wing area: 17.32 m2 (186.4 sq ft)
Empty weight: 2,158 kg (4,758 lb)
Gross weight: 2,693 kg (5,937 lb)
Max takeoff weight: 2,800 kg (6,173 lb)
Powerplant: 1 × Gnome-Rhône 14N-25 14-cyl. two-row air-cooled radial piston engine, 805 kW (1,080 hp)
or 1 x Gnome-Rhône 14N-49 engine rated at 820 kW (1,100 hp)
Propellers: 3-bladed variable-pitch propeller
Maximum speed: 509 km/h (316 mph; 275 kn)
Cruising speed: 450 km/h (280 mph; 243 kn)
Range: 600 km (373 mi; 324 nmi)
Service ceiling: 10,000 m (32,808 ft)
Time to altitude: 2,000 m (6,600 ft) in 3 minutes 24 seconds
Wing loading: 155.4 kg/m2 (31.8 lb/sq ft)
Armament: 2 × 20 mm HS.404 cannon with 60-rpg + 2× 7.5 mm MAC mg with 500 rpg
or 4 × 7.5 mm MAC mg with 500 rpg
The result, designated MB.155 performed favourably in flight tests and was ordered into production in 1940, however only 10 aircraft had been completed by the Fall of France. Under the terms of the armistice, the remaining 25 on the production line were completed and delivered into Vichy service. From there, some eventually made their way into the Luftwaffe after 1942.
The final member of the family, the MB.157 utilised a far more powerful engine and eventually became a very different aircraft as the design evolved from the MB.152 to accommodate the larger and heavier powerplant. Unfinished at the time of the armistice, it was ordered to be completed and flown under German supervision. Demonstrating superb performance, it was taken to Orly where the powerplant was removed for testing within a wind tunnel. The excellence in the design was confirmed. It was later destroyed in an Allied air raid.
MB.151s and MB.152s equipped nine Groupes de Chasse (fighter groups) during the Battle of France, but they were largely outmatched by the faster Messerschmitt Bf 109E. Six groupes continued to fly in the Vichy French Air Force until this was disbanded on 1 December 1942, the aircraft being passed over to the Royal Romanian Air Force by the Germans.
Though the Greek government had ordered 25 MB.151s, actually only nine of these were exported to Greece. They flew with the 24th Moira Dioxis (Fighter Squadron) of the Hellenic Royal Air Force in Elefsina against the Italians and Germans, scoring several air-to-air victories until 19 April 1941, when the last MB.151 was shot down.
During World War II, the Bloch MB.152 had destroyed at least 188 enemy aircraft, and lost about 86 of their own. They proved tough aircraft, able to stand considerable battle damage, and a good gunnery platform, but with many problems: poor agility, poor weapon reliability, poor range (600 km, but here the Bf 109E was only slightly better, around 660 km), and were notably underpowered.
In 1944, several surviving MB.152s were liberated at an airfield in mid-southern France. After being flight-tested and evaluated, and painting out the balkenkreuzen and swastikas, they were fitted with more powerful American engines and went up against the last remnants of the Luftwaffe with the Free French.