its performance shortcomings; its inadequate manoeuvrability and its range. Following the Armistice, six groups 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. By April 1941, the German Armistice Commission had agreed with a proposal to standardise the Vichy Air Force onto the Dewoitine D.520, resulting in all other single-engine fighters being phased out. The Germans seized around 173 fighters, 83 of which being reportedly serviceable, which were pressed into service with the Luftwaffe. Chrisesco alleged that around 95 MB.152s were secretly modified during late 1941 – early 1942 with a rear-fuselage fuel tank, giving them the range to cross the Mediterranean Sea to freedom. Though the Greek government had ordered 25 MB.151s, actually only nine of these were actually exported to Greece by the time of the Armistice being signed. Those that were delivered were still in the process of working up when the Greco-Italian War broke out, leading to the wider Balkan Campaign between the major European fighters. The MB.151 fighters flew with the 24th Moira Dioxis (Fighter Squadron) of the Hellenic Royal Air Force, stationed at Elefsina against the Italians and Germans, scoring several air-to-air victories until 19 April 1941, when the last of Greece's MB.151s was shot down. At one stage, the Bulgarian government was in the process of negotiating the acquisition of MB.152 fighters with the Vichy government. During February 1943, a contract for delivery of 20 aircraft was signed, but this was vetoed by the German authorities, which by now had a controlling say within Vichy French politics. Instead, Bulgaria later received a series of Dewoitine D.520s to meet their needs. Variants MB.150 Single MB.150.01 prototype powered by a single Gnome-Rhône 14N-07 MB.151 MB.151.01 prototype and MB.151.C1 initial production versions powered by 920hp Gnome-Rhône 14N-35 engines (144 built) MB.152 MB.152.01 prototype and MB.152.C1 up-rated production versions produced in parallel with 151.C1, powered by 1,050hp Gnome-Rhône 14N-25 engines. (482 built) MB.153 Single MB.153.01 prototype with Pratt & Whitney R-1830 Twin Wasp engine MB.154 Proposed version with Wright R-1820 Cyclone engine. Not built. MB.155 MB.155.01 prototype converted from a MB.152 and MB.155.C1 production versions powered by Gnome-Rhône 14N-49 engines (35 built) MB.156 Proposed version with Gnome-Rhône 14R engine. Not built. MB.157 Single prototype of advanced version, converted from the MB.152 and equipped with a