The Airspeed AS.51 Horsa was primarily a wooden troop-carrying assault glider, designed and built by Airspeed (1934) Limited, specifically for use during World War II.

The Air Ministry issued Specification X.26/40 calling for a large glider aircraft, capable of accommodating up to 30 fully-equipped paratroopers, destined for operations in Northern France. Amongst the particulars was the instruction that the aircraft should make use of wood as its main construction material, in order to conserve critical supplies of metals.

Airspeed (1934) Ltd was amongst the companies receiving the specification and produced initial designs at Hatfield, under the leadership of A Hessell-Tiltman. The war effort was in full swing at the parent de Havilland Aircraft Company, which had recently acquired a controlling interest in Airspeed, so the team was based in the classrooms of the de Havilland Technical School.

This was never ideal due to the constant threat of air raids and so the Airspeed team relocated to Salisbury Hall, at nearby London Colney. Salisbury Hall was also the home of the DH98 Mosquito design team, led by Ralph Hare and Ron Bishop. The DH98 Mosquito was subsequently dubbed ‘The Wooden Wonder’ and so the synergy between the two projects was of great benefit.

The final design for the new glider was completed in just 11 months, an extraordinary achievement given that Britain was at the height of its conflict with Germany at the time and the Battle of Britain was being fought in the skies of southern England.

With the designs complete, the first two prototypes were built at Salisbury Hall before being transported to the Fairey Aviation Works at Hayes, near the Great West Aerodrome, where the first prototype (DG597) was first flown on 12th September 1940 by George Errington. It was first towed into the skies over West London and Berkshire by an Armstrong Whitworth Whitley then released and, after a short period, landed with very little difficulty. Allocated the Airspeed designation AS.51, the type was christened ‘Horsa’, after the legendary fifth-century conqueror of southern Britain. Five additional prototypes were then quickly assembled and test flown at the Airspeed Works in Christchurch, Dorset.

As soon as production began, a number of suggested improvements and refinements were made by expert subcontractors, some with decades of wooden furniture experience. These resulted in the Airspeed AS.58 Horsa II.

This was a modified design featuring a reinforced floor, together with a hinged nose section in order to accommodate military vehicles for both transport and combat roles. Another significant upgrade was fitting a stronger twin nose-wheel, plus a modified tow attachment. All of these added to an increased all-up weight of 15,750 pounds (7,140 kg). It should be noted that although Airspeed (1934) Limited was responsible for most aspects of the Horsa II, they never manufactured or assembled any of this marque.

With seating for up to 30 troops, the Horsa was much bigger than its American contemporary (the Waco CG-4A) which only had a capacity of 12.

The type’s most famous sortie was carried out by six Horsas, codenamed Operation Deadstick and delivered an advance force of 80 paratroopers, on the evening of 5th June 1944, the night before the D-Day landings. These men, from D Company of the 2nd Oxfordshire & Buckingham Light Infantry, were transported by the Glider Pilot Regiment into the countryside, just four miles from the Normandy coast. Under cover of darkness and after an almost silent approach, they were responsible for successfully securing the strategically important bridge (now known as Pegasus Bridge) at Bénouville, over the Caen Canal in Normandy.

The Horsa was a major factor in a number of operations that followed the successful Normandy assault. These included Operation Dragoon and Operation Market Garden, which involved 1,205 gliders in 1944. A year later Horsas were involved in Operation Varsity (March 1945) when 440 aircraft carried soldiers of the 6th Airborne Division across the Rhine, in the type’s final operation of the war.