On 24 September 1916, the destiny of British airship flying changed dramatically. Until that time, British designers and constructors in government and private industry had lagged behind their German counterparts. But as the sun rose that morning over the fields beside the Essex village of Little Wigborough, it revealed the vast – and remarkably well-preserved – skeleton of one of the newest German naval Zeppelins, the L33.
L33 had been brought down the night before when it had been taking part in a large-scale bombing raid on London and Essex. The craft had come to earth relatively gently, and despite the best efforts of the crew to destroy it before they were apprehended, the structure and mechanics were virtually intact, with only the outer covering and gasbags largely burned away.
The Admiralty, which had authority over airship design, moved immediately to protect the wreck, and then to study it. British rigid airships were neither as advanced or as successful as German ones. The first British rigid airship, HMA No 1 (known unofficially as ‘Mayfly’) built between 1909 and 1911 was an embarrassing failure. It was drastically overweight, and broke its back before a flight could be attempted. Indeed, the German rigid airships had started in a manner that was barely more successful, but Count von Zeppelin’s drive and persistence, and the faith of his backers, meant that by trial and error, the highly successful craft of WW1 could be developed. Britain was starting later, and in a more halting fashion – Vickers’ airship design team was disbanded after the Mayfly failure. A second British rigid airship was commissioned in 1913 – HMA 9r, which was partly based on knowledge gleaned from the hurried examination of Z IV by the French that year. On the outbreak of war, 9r was almost finished but construction was suspended by First Lord of the Admiralty Winston Churchill, and the design team (including a youthful Barnes Wallis), dispersed.
Later, the decision was reversed and 9r was completed, and further rigid airships commissioned. But 9r had only been ready three months when L33 fell into the Admiralty’s lap, and the successor 23r class were still a year away from being ready. (In fact, 23r would be fitted with an engine taken from the wreck of L33!) The Admiralty was now well and truly sold on the benefits of airships, with their high loitering time and ability to spot submarines more easily than fixed-wing aeroplanes. A large number of non-rigid airships were now in operation, and providing sterling service, particularly with convoy escort, but it was not until the 23X class (an improved 23) that the Navy would have any rigid airships able to undertake operational service. Only one, R29, met the enemy in combat, helping to destroy two submarines.
L33 was state of the art compared with the mostly dated and overbuilt British rigid airships – even the 23X class. Her streamlined hull form was much more efficient than the parallel-sided British ships. Her engines were more powerful and reliable, she was stronger and yet lighter for her size, which was much bigger overall than the British ships. The Admiralty went over the considerable remains with a fine-tooth comb, going so far as to recover items that had been taken from the site before the guards had arrived (and prosecute those who failed to hand their ‘souvenirs’ in), and elected to create virtual copies. Naturally, by the time they were completed, it could be expected that German airships had advanced further, but nevertheless, the blueprint provided by L33 gave the British industry a huge shortcut towards modern rigid airship designs.
And the design did not remain a slavish copy. Although the overall pattern and structure of the new British airships – coincidentally starting with the R33 – followed L33’s closely, their propulsion and other systems was amended during the design and construction process to mirror new Zeppelin developments. For example, the outer aft propellers were no longer to be mounted on outriggers and connected to the rear gondola by inefficient driveshafts. Instead, the rear engines were coupled to run a larger propeller on the gondola. The forward gondola was split into two, the after part containing an engine, and the forward part containing radio direction-finding equipment, with the slight gap (faired over with canvas) avoiding vibration being transferred from the engine to the sensitive equipment.
The first of the R33 class appeared after the armistice of 1918, but still before the Treaty of Versailles had been signed, so if hostilities had recommenced, the RAF, which had taken over flying from the Royal Naval Air Service, would have had an effective and modern rigid airship.
As it was, R33, built by Armstrong Whitworth, was used for various propaganda and trials purposes, transferred to civilian authority and mothballed, then reconditioned in the 1920s to assist with the development of the UK’s ambitious airship programme. One area where the British innovated was in the development of mooring masts, where German practice was simply to manoeuvre the airship on the ground with the aid of handling parties.
R33 proved the soundness of her design when she was damaged in a storm on 16 April 1925, and driven over the North Sea. She did not crash, nor even have to make an emergency landing, but the skeleton crew on board were able to keep her in the air until the winds abated and they could make their way back to Norfolk from the Dutch coast.
R34, the second vessel in the class, built by Beardmore, was even more prestigious, making the first East-West crossing of the Atlantic, and the first return crossing, achieved in July 1919.
R35 was cancelled, and R36 was modified while under construction to a lengthened design incorporating developments from newer captured Zeppelins. She also provided valuable service and lessons, including endurance flights of 30 hours, for the airship service that, tragically, would never come to fruition. Without question, the British airships that were conceived with the capture of L33, were the most successful, safe and effective in British service.