Operational History of The Savoia-Marchetti SM.81 - Spanish Civil War

Spanish Civil War

The main career of the SM.81 started on 28 July 1936. On a mission dedicated to supporting General Francisco Franco and his "alzamiento" (uprising) against the Republican government at the start of the Spanish Civil War; 12 SM.81s under the guise of Spanish civilian ownership took off from Elmas, near Cagliari, to fly to Morocco carrying 63 non-uniformed troops led by Colonel Ivanoe Bonomi. The anticipated ferry flight was around 1,135 km (705 mi), but several problems occurred en route.

The journey should have been flown in less than four and a half hours at 260–270 km/h (160-170 mph), but on encountering strong headwinds at 1,000 m (3,280 ft) they climbed to 3,500 m (11,480 ft). the best cruise altitude for the Alfa Romeo 125 engines. After five hours they were still an hour from their final destination of Melilla in Morocco. Trying to maintain tight formation despite the clouds was also fuel-costly, with non-linear flight, only nine aircraft managed to land at Melilla. One ditched in the sea, another crash-landed and a third force-landed without damage in Algeria. The remaining aircraft arrived with an average of only 130 L (34 US gal) of fuel remaining in the tanks, the most being the 200 L (53 US gal) left. This aircraft was sent to search for the missing SM.81s. Being only 3% of the total fuel capacity, this was enough for just a few minutes of flight and meant that, with only a slightly stronger headwind, all of them would have been lost or forced to land in Algeria. The surviving aircraft were valuable assets and soon put to use as troop-transports and bombers.

Franco's Spanish Army of Africa troops were fundamental to raising the fortunes of the alzamiento which had hitherto been mainly beaten by the Republican loyalists. On 6 August 1936, African troops were transported to Spain aboard four merchant ships. The threat of the SM.81s and their bombs, once reinforced by the Italian ship RM Morandini, were sufficient to keep the mainly Republican Spanish fleet at bay, which otherwise would have been able to prevent any Franchist convoy reaching Spain. On 9 August, SM.81s under the command of Ettore Muti, destroyed the Spanish Navy's fuel and ammunition reserves in the vicinity, forcing the fleet to use northern bases and further preventing interference with the sea-transport of Hispano-Moroccan forces.

After these exploits, the initial SM.81s were reinforced by aircraft from four other squadrons: 213, 214, 215 and 216 in two Groups (XXXIV and XXXV), and by 251 and 252 squadrons for the XXV ("Pipistrelli") Group. Throughout the war, SM.81s were used as attack aircraft as well as in the transport role and as bombers. Although some missions were flown with Fiat CR.32 fighter escorts, unescorted day missions were only made possible by flying in tight formation with mutual machine gun protection, and by the aircraft's ability to fly on instruments while in cloud. Sorties were increasingly flown at night after the arrival of Polikarpov I-15 and I-16s in Spain, at which point only seven of the original nine aircraft were still serviceable, having released 210 tonnes (230 tons) of bombs and contributed (together with Junkers Ju 52s) to 868 flights transporting Morocco's troops. After thousands of hours flown by 90 to 100 aircraft, at least 64 surviving SM.81s were left behind in Spain in the G-12 Group at the end of 1938. One example was lost near the end of the war in 1939 along with the lives of many senior officers. The precise total number of SM.81 losses during the war in combat and from operational causes is not known.