'Monsoon' was a British operation to deliver crated aircraft by ship to Takoradi on the coast of West Africa for local assembly and then air self-delivery to the Middle East across the African continent (January 1941).

The undertaking represented an early stage of the major British effort to keep their air units in North Africa and East Africa supplied with aircraft. Before Italy’s entry into the war on 10 June 1940, aircraft travelled to the Middle East either by sea along the short Mediterranean route, or by flying in easy stages by way of southern France, French North Africa, Malta and the Western Desert. After the Italian entry into the war, however, the passage of any convoy right along the Mediterranean entailed a major naval operation and, when France was forced out of the war late in June 1940, only the longer-range types such as the Bristol Blenheim light bomber and Vickers Wellington medium bomber could make the trip by air. Even these would face considerable dangers including with a night flight from the UK across the Bay of Biscay, the unpleasantly short runway at Gibraltar, and the night landing and take-off at Malta. Shorter-range aircraft could travel only by sea, however, and this would almost certainly entail a long and time-consuming journey round the Cape of Good Hope.

The route linking Gibraltar and Malta, and that linking Takoradi and Khartoum might between them serve for aircraft, but other essentials for the RAF and nearly all military reinforcements and supplies still had to make the long sea passage round the Cape of Good Hope in the face of possible U-boat attacks in the North and South Atlantic, and Italian air and submarine attack from Somaliland and Eritrea in the western Indian Ocean and Red Sea.

Improvement in the security of the reinforcements and supplies passaging to Egypt therefore required, in the short term, British air and sea superiority in the Gulf of Aden and the Red Sea and also, in the longer term, the removal of the Italians from their East African possessions. At the end of June 1940 the Italian forces in Eritrea, Italian Somaliland and Abyssinia totalled more than 200,000 men and 150 aircraft, against which the British could oppose slightly more aircraft but only some 19,000 men. Nevertheless, the British forces hemmed in the Italians from Sudan, Aden, British Somaliland and Kenya.

Even so, an alternative which the Air Ministry was quick to explore was the possibility of saving valuable time and shipping volume if short-range aircraft made at least part of the journey under their own power. Fortunately this was possible, for the completion of a number of pioneer survey flights before World War II had created the possibility of an air route linking Egypt and the west coast of Africa. By 1936 Imperial Airways was operating a weekly service between Lagos and Khartoum, at which point it connected with the regular route from England to the Cape of Good Hope. Thus there was already a series of primitive landing grounds spanning the African continent, although these landing grounds were located very far apart.

Almost immediately after the Italian entry into the war, the Air Ministry decided to use this route to reinforce the Middle East. An early decision was to base the western end of the route at Takoradi in the Gold Coast, which had been developed in the previous decade for the cocoa and manganese trade, as this provided better airfield and harbour facilities than Lagos in Nigeria. Its drier climate, too, would have less disastrous effects on aircraft left in the open. Thus Takoradi became the sea/land interchange point at which created aircraft would be unshipped and erected for their 4,000-mile (6450-km) flight across Africa.

An advance party of 24 RAF personnel reached Takoradi on 14 July 1940 under the command of Group Captain H. K. Thorold, an experienced maintenance officer. Thorold was quickly able to confirm the suitability of Takoradi, then set his group to work organising essential facilities such as roads, gantries, hangars, workshops, store houses, offices and living accommodation.

Thorold was also tasked with turning the primitive trans-continental landing grounds into efficient staging posts and perfecting radio communications along the whole route. The first stage, 378 miles (608 km) of humid heat and beset by sudden squalls, followed the coast to Lagos, with a possible halt at Accra. Next came 525 miles (845 km) over hill and jungle to a dusty airfield outside Kano, after which 325 miles (523 km) of scrub brought the aircraft to Maiduguri. A stretch of hostile Vichy French territory some 650 miles (1046 km) wide, consisting largely of sand, marsh, scrub and rocks, then brought the aircraft to El Geneina in western Sudan. There followed 200 miles (322 km) of mountain and great heat to El Fasher, and then 560 miles (901 km) to the north-east to Khartoum. From here the route extended some 1,000 miles (1610 km) to the north across two wide bends of the Nile river to Wadi Halfa and thence along the Nile river via Luxor to Abu Sueir near Cairo.

The main RAF party of some 350 officers and men, including 25 ferry pilots, joined Thorold’s initial group at Takoradi on 24 August. Small maintenance parties were sent out to the staging posts, British Overseas Airways Corporation navigators were enrolled for the initial flights, and BOAC aircraft were chartered to return the ferry pilots from Abu Sueir. It was also laid down as a general principle that single-seat fighters should be led by a multi-engined aircraft with a full crew.

With these preliminaries arranged, and a first semi-experimental delivery began on 15 November 1940 with the 'Stripe' delivery of the first aircraft, and continued on 19 December 1940 as the elderly fleet carrier Furious departed the UK for Takoradi with nine Fairey Fulmar carrierborne and 39 Hawker Hurricane land-based fighters to arrive on 19 January 1941 under escort from Freetown, Sierra Leone, by the light cruiser Delhi and destroyers Encounter and Isis, the first consignment of six Blenheim Mk IV light bombers and six Hurricane fighters docked at Takoradi on 5 September, to be followed on the following day by 30 Hurricane fighters in the elderly carrier Argus. These aircraft were complete except for their outer wing panels and long-range tanks. No time was lost. The Port Detachment of Thorold’s unit quickly unloaded the aircraft and transported them to the airfield. There the Aircraft Assembly Unit took over, exercising much ingenuity to make up for the unexpected absence of various items, including the humble but essential split-pin. Last-minute difficulties, including the collapse of the main runway on 18 September, were rapidly overcome, and on 19 September the first air convoy of one Blenheim and six Hurricane machines, was ready for the flight to Egypt.

By now French Equatorial Africa, between north-eastern Nigeria and western Sudan, had joined the Free French movement, and the pilots had the consolation of knowing that they would be flying all the way over territory which was diplomatically well disposed, if unfriendly in other respects.

The Blenheim accelerated along the runway, took off, climbed, and circled, to be joined in a few moments by its six charges. Seven days later, on 26 September, one Blenheim and five Hurricane fighters reached Abu Sueir.

A series of small campaigns associated with the air ferry route across the Sahara were those in the Fezzan, which took the form of incursions into, and then the crossing of, this Italian-held desert in southern Libya by Général de Brigade Charles de Gaulle’s Free French forces commanded by Colonel Philippe Leclerc. These forces comprised Tirailleurs Sénégalais and Chad infantry, and the camel-mounted Groupe Nomade de Tibesti, supported by radio and navigational units of the Long Range Desert Group and, at first, 14 bombers.

The successes of these forces, which were based at Fort Lamy in French Equatorial Africa and raided to the north past the Tibesti mountains into southern Libya, prevented the Italians from interfering with the Takoradi air route. The Chad area from which these campaigns were launched was the only Free French territory contiguous with Axis soil: in the view of de Gaulle, if the British were forced out of Egypt, which seemed likely in 1941, the area could be of pivotal importance in defending the rest of colonial Africa. de Gaulle was therefore convinced of the importance of taking the offensive in the area.

After Major Jean d’Ornano of the Chad garrison had been killed during the first Free French and LRDG raid into the Fezzan in January 1941, Leclerc replaced him. Based at Fort Lamy, and staging through Largeau (Faya), Leclerc’s force took Kufra oasis in March 1941. Then, this time staging through Largeau and Zouar, the French raided Italian outposts in the area of Murzouk, the Fezzan capital, in the following February. Then in December 1942 Leclerc sent 3,250 men and 1,000 vehicles supported by 12 aircraft to destroy all Italian resistance around Murzouk, which was occupied on 12 January 1943, and tackle the Italian outposts at Tegerhi, Ouaou el Kebir, Zuila, Gatrun and Ghat. Heading to the north toward the Mediterranean, the French force then took Sebha, Brach, Hun and Ghadames before overcoming stiff opposition at Mizda, which they captured on 22 January, before entering Tripoli on 26 January after covering 1,600 miles (2575 km) since leaving Chad. Leclerc’s unit then became part of General Sir Bernard Montgomery’s British 8^th Army as 'L' Force.