Lighter Than Air

by Guy Warner

  In the bitter and crucial Battle of the Atlantic in 1942, nearly 500 merchant ships were sunk on the eastern seaboard of the USA alone. Remarkably, part of the answer was found to be the establishment of an eventual total of five Fleet Airship Wings, with a strength of more than 100 blimps in fifteen squadrons stationed not only on either side of the continental USA, but also in Jamaica, Brazil, Trinidad, French Morocco and Gibraltar; patrolling an area of over three million square miles (7.8 million square kilometres) over the Atlantic and Pacific Oceans, and the Mediterranean Sea between 1942 and 1945. They were very reliable, being available for duty eighty-seven per cent of the time; 35,600 operational flights were made in the Atlantic and 20,300 in the Pacific, for a total of 5,550,000 hours in the air escorting 89,000 ships loaded with troops, equipment and supplies. No ship escorted by a blimp was ever sunk and only one of the airships was lost to enemy action – K-74, which fought a duel with a U-boat.24

  After 1945 the USN carried on with using blimps in anti-submarine warfare, search and rescue (SAR) and early warning roles. Some were equipped with huge airborne radar sets for early warning of bomber attacks against the USA. Two of the largest airships were the ZPG-2 at 324 feet (99 metres) in length and a capacity of 875,000 cubic feet (24,777 cubic metres), and the ZPG-3 at 403 feet (121 metres) long and a capacity of 1,516,000 cubic feet (43,000 cubic metres), the latter being the largest blimp ever built. An airship of this type could stay aloft without refuelling for more than 200 hours. On 31 August 1962, the navy ended its use of blimps. In the 1980s the USN examined once more the possibility of reviving airships, but Congress terminated funding for the project in 1989.

  [Author’s note: It is of interest to note that Betty Usborne’s son, John Godley, later Lord Kilbracken, took part in successful anti-submarine operations, based in Ireland during the Second World War, which used what was regarded as outmoded technology. Maydown, in Co Londonderry, was the headquarters for MAC (Merchant Aircraft Carrier) ship operations. This type of aircraft carrier proved to be a highly effective countermeasure to the U-boat offensive from mid-1943 onwards. These were standard grain carriers or oil tankers fitted with an elementary flight deck from which a flight of three or four Swordfish biplanes was operated. Each flight of Swordfish flew from Maydown to join the carrier off the Irish coast, and returned to base after the journey across the Atlantic and back. It is a remarkable fact that, of the 217 convoys in which a MAC ship sailed, between May 1943 and the end of the war, only one was attacked successfully by a U-boat. Three parent units for the Swordfish were based at Maydown, 836 and 860 NAS, for operational deployment, and 744 NAS for training; 836 was the largest operational squadron in the FAA. Together, the Maydown squadrons provided over ninety Swordfish for some nineteen MAC ships. The last FAA squadron to relinquish the famous Swordfish was 836 at Maydown in July 1945. Northern Ireland remained a very important location for air anti-submarine activity for the next thirty years, with the Joint Air Submarine School (JASS) at Londonderry until 1969, the Air Anti-Submarine School at RNAS Eglinton (now City of Derry Airport) which closed in 1959 and RAF Coastal Command Shackletons flying from Aldergrove until 1959 and Ballykelly until 1971. The long tradition of maritime surveillance in Ireland is now maintained by the Irish Air Corps from its base at Baldonnel on the outskirts of Dublin.]

  The British Army Considers an Airship

  Remarkably, a plan conceived in the mid-1990s renewed the British Army’s connection with lighter-than-air aviation after a gap of some eighty years – in the bulbous shape of ZH762, a Westinghouse Skyship 500 built by Airship Industries of Cardington. It was 170 feet (52 metres) long, 46 feet (14 metres) in diameter and had a capacity of 182,000 cubic feet (5150 cubic metres). The helium-filled envelope was laminated, lined with gas-retention film and sprayed externally with a polyurethane coating. The car was attached to the envelope and was made from reinforced plastic; it was powered by two Porsche 930 engines of 205 hp (151kW) each, and, as with previous blimps, they were fitted with swivelling propellers and its ballonets were fed from the slipstream. Skyships have been used for tourist flights, fishery patrols, aerial photography and a range of other activities. This airship was flown by Army Air Corps pilots in the course of an extensive trials programme, which included a visit to 5 Regiment AAC at RAF Aldergrove. It had the advantages of being able to lift a considerable quantity of mission-related equipment and of being able to remain in the air for protracted periods of time. Against these benefits had to be set the undeniable facts that it was slow, not being capable of more than 30–40 knots (34–45mph/55–74kph) cruising speed and that it was not well-suited to windy or icy weather conditions. Useful experience was gained, but the AAC decided in the end not to establish a new airship unit.

  Westinghouse Skyship 500 ZH762 at RAF Aldergrove in 1995. (5 Regiment AAC)

  The Airship Plane

  The last scheme hatched by Neville Usborne was the one that would result in his tragic, early demise – the idea of an aeroplane carried aloft by an airship. Though further development of the AP-1 was terminated, aircraft were indeed to be borne aloft by airships. Trials were carried out by both the British and the Germans in 1918. On 26 January, an Albatros D.III single-seat fighter, serial number 3066, was fixed under the airship L35 (Zeppelin LZ 80) of the Imperial German Navy to test the idea of protecting airships by attaching a fighter which could fly off to defend the mother ship if it was attacked. The pilot was in the cockpit throughout and could not be transferred in flight. The trial was a success in that the Albatros, which had kept its engine running for the duration of the flight as there was no way of manually restarting it once the Zeppelin was airborne, was released from a height of some 5000 feet (1500 metres) and flew away safely. Then, on 6 November, Sopwith 2F.1 (or ‘Ships Camel’ as it was commonly known) N6814, flown by Lieutenant R.E. Keys, DFC, of No 212 Squadron RAF, was dropped from the British airship R23 and landed at Pulham in Norfolk. R33 was the next British rigid to be used for experiments of this nature, releasing a pilotless Sopwith Camel in 1920 and then from October 1925 not only releasing, but also recapturing aircraft in the air. A specially developed trapeze was attached to the envelope from which was suspended a DH53 Hummingbird lightweight singleseater. When R33 had attained a height of 3800 feet (1150 metres), Squadron Leader Rollo Amyat de Haga Haig climbed down a ladder into the cockpit, the trapeze swung down and the Hummingbird, J7326, was released. He dived until the engine started, performed two loops and returned to the airship to hook on. As he came in to engage, the aircraft touched one of the trapeze stay wires and the propeller was smashed. The pilot then disengaged the suspension gear and dropped down to glide to Pulham airfield below. On investigation it was decided that the approach of the pilot had been incorrect and the trapeze should have only been lowered when he was approaching from the stern, then there would have been a perfect approach with the nose gear slotting easily into place. The second attempt was also imperfect and once more the pilot landed on the ground. The third try, on 4 December, was completely successful, flying J7326. The following year the same experiment was made with a pair of Gloster Grebe II fighters, J7385 and J7400; both were dropped successfully in October and November, but no attempts were made to hook on again. The first successful launch was achieved on 21 October 1926. The pilot was Flying Officer R.L. Ragg (Later Air Marshal, CB, CBE, AFC) of the Royal Aircraft Establishment.

  R23 and Sopwith 2F.1 Ship’s Camel N6622 in the shed at Pulham in 1918. It was also launched successfully and flown by Lieutenant Keys. Note C*9 in the background.

  R23 and Camel N6814.

  DH53 Hummingbird J-7326 suspended from R33 during trials in 1925.

  The most persistent and effective users of this idea were in the USA. The US Army Air Service experimented in 1923–1924 with a Sperry Messenger and Army Corps blimps TC-7 and TC-3, conducting numerous flights achieving successful launch and recovery. The US Navy devoted a great deal of time and resources to examining the possibility of using airship-borne
aircraft as fleet scouts. Tests were conducted using the USS Los Angeles. A rigid ‘trapeze’ was installed on the airship and a programme of flights was undertaken from 1929 onwards, the first successful ‘hook on’ being made on 3 July 1929 by Lieutenant A.W. ‘Jake’ Gorton, flying a Vought UO-1.25 In January 1928, the Los Angeles had also made a successful flight some 100 miles (161 kilometres) out to sea off the coast of Rhode Island, to land on the deck of the seaplane carrier, the USS Saratoga; she then followed up in March with a flight of 2265 miles (3624 kilometres) in forty hours from Lakehurst, New Jersey, to Panama, Cuba and back.26

  The USS Akron’s design included a hangar aft of the control car and crew’s quarters. At the time of her early flights, however, no aircraft were carried. In February 1932 a trapeze was installed. Unlike the device on the Los Angeles, it included a winch which allowed the hooked-on airplane to be hoisted through a T-shaped door into the belly of the airship, where it was then transferred onto an overhead trolley system and rolled into one of the four spaces provided in the hangar. The hook-on operations began in May 1932. On 4 May 1932, a Consolidated N2Y-1 successfully hooked on to the Akron’s trapeze and was hoisted inside the giant airship’s hangar.

  USS Los Angeles moored to USS Patoka.

  The USN then ordered a new design of aeroplane which many have believed was specifically for the role of airship operations, the Curtiss F9C-2 Sparrowhawk. It was in fact developed from a specification for a very small carrier-borne fighter.27 It was a stubby little aeroplane and could fit inside the airship’s hangar, and was first hooked-on to the Los Angeles in October 1931. The training carried out included night hook-ons for which the only illumination of the trapeze was by hand-held flashlights.28 The Heavier-than-Air Unit of ZRS4 and ZRS5 began operating as scouts from the Akron the following year, but as mentioned above, the airship was destroyed in 1933. It had been discovered that the process of hooking-on required no extraordinary flying skills. The relative speed of the airship and the aeroplane were almost zero, the pilot approached the trapeze in an almost stalled attitude and slid his skyhook over the yoke of the trapeze. A spring-latch prevented him from drifting back off the yoke. If he stalled completely during his approach, he had at least 1000 feet (404 metres) of altitude in which to recover and then try again. Taking off was even easier, he simply pulled a lever in the cockpit to release the skyhook. The USS Macon also had provision for Sparrowhawks. They proved to be a success in scouting up to 200 miles (320 kilometres) ahead of the airship and their range was extended by removing their landing gear during over-water operations, replacing this with a belly fuel tank, which increased the aircraft’s range by fifty per cent. On 19 July 1934, just how effective they could be was demonstrated. President Roosevelt was aboard the cruiser USS Houston, steaming west across the Pacific towards Hawaii. At noon, to the astonishment of the ship’s crew, two tiny aircraft were spotted diving toward the ship, which they then circled – to the President’s delight. As they were more than 1,500 miles (2400 kilometres) from land it seemed impossible that any aircraft could have the range required to operate so far from base. No aircraft carriers were operating anywhere nearby. Then Macon appeared overhead and orchestrated a series of demonstrations, during which the aircraft dropped mail and messages, which were recovered and winched into the airship’s hangar. The President radioed the airship’s commanding officer congratulating him; it had been a highly effective piece of publicity for the US Navy. Sadly, all such experiments came to an end when the Macon too was lost. Remarkably, the crash site was found in 2006 and the wreckage of several Sparrowhawks was discovered on the sea bed. A plan to construct the much larger ZRCV, which would have carried nine dive-bombers, was never taken beyond the concept stage.29

  On 7 July 1933 the first Sparrowhawks hooked on to the USS Macon.

  A F9C-2 Sparrowhawk attached to the trapeze of the USS Macon.

  Finally, in the spring of 1937, General Ernst Udet, flying a Focke-Wulf FW-44 Stieglitz made either one or two in-flight hook-ons to a trapeze fitted to the German Hindenburg. The aim of this project was to develop an aerial delivery system for mail or passengers. The trials were not wholly successful as Udet experienced considerable difficulty attaching the light training biplane to the trapeze in the turbulent air underneath the airship.

  Conclusions

  It remains to evaluate and to guess where Neville Usborne’s ability and desire for success could have taken him had he not met his untimely end. His ambition and technical ability took him to Barrow and HMA No 1, the ability he displayed there, despite the failure of the Mayfly, saw him posted to Farnborough, where he really learned to become an airshipman. Fortunately, the Royal Navy retained just enough of an interest in airships to allow Usborne to be in the right place at the right time, Kingsnorth, so that all that he had learned could be put into effect in the design of two highly successful classes of airship. Sadly his bravery and his questing intelligence, his desire to solve the pressing Zeppelin problem, resulted in his untimely and tragic death. He was admired by his peers, many of whom reached high rank in the RAF or the RN, or high positions in civil aviation. He was well-connected socially, ambitious, dynamic, commercially and mechanically minded, and also had the ear of a leading industrialist. In November 1915 Usborne drew up proposals for the formation of a post-war aeroplane company.30 He envisaged a small number of skilled designers working for a company which would supply aircraft, flying schools, repair facilities, the design of aerodromes, and which would acquire the rights for mail services to developing markets in foreign countries (eg South America). His fertile mind also considered USA to Europe mail and passenger services. He had concluded that airships would not be viable as a commercial success except perhaps for very long overseas journeys. He was by no means alone in this supposition. For example, on 3 May 1919, a regular columnist for the Belfast daily morning newspaper, the Northern Whig, who wrote under the pseudonym ‘An Old Fogey’, wrote an article entitled ‘Ulster’s Great Aerodrome’. He was moved to quote Lord Tennyson, who foresaw, ‘the nation’s airy navies grappling in the central blue,’ which had certainly been realised in the preceding four years, but he also looked forward to another of his lordship’s predictions coming to pass, ‘the heavens filled with commerce, argosies with magic sails, pilots of the purple twilight, dropping down with costly bales.’ There then followed a speculative section entitled Commercial Flying; ‘Now the Air Ministry have published a map showing several routes for the guidance of pilots, and have issued a set of rules of the road and a scale of the charges to be made for the accommodation of civil aviators and their machines at government aerodromes, including Aldergrove. Transatlantic commercial flying, in the opinion of experienced aviators, will come in the near future and the importance of Aldergrove may be still further enhanced by its becoming an important transatlantic air station. Then we may expect announcements in our Saturday morning newspaper such as the following – “Belfast and New York Air Service – Departures from Aldergrove next week as follows: Thursday, Dalriada 3000 hp: Saturday, Ben Madigan 4000 hp: both Belfast built airships. For passage apply etc.’”

  His letter of 7 January 1916 to Vickers, with his proposals for post-war aerial transport, received an encouraging reply from the chairman, Sir Trevor Dawson, who himself had been a gunnery officer in the Royal Navy in the 1880s and 1890. Success in the aviation business after the First World War was much on the minds of many of those who had gained vast flying experience during the conflict. Some tried breaking long-distance records, others joined the fledgling airlines and many more set up joy-riding companies. Few in the end made their fortunes. Two ex-military airmen were particularly successful; Sir Alan Cobham, who founded Flight Refuelling Limited after a decade of long distance flights and air displays all around the UK, and Ted Fresson, who was the pioneer of civil aviation in the far north of Scotland and the Isles. Perhaps Usborne could have joined this very short list, but it would have been a struggle. It was not until the 1930s that civil ai
rcraft were designed in Britain that were sufficiently cost-effective to make running an airline in any way economically viable. Even then the biggest players were: the Government and Imperial Airways; the four big railway companies and Railway Air Services; and the investment house Whitehall Securities and British Airways. Industrially, Sopwith, Vickers, Handley Page, De Havilland, Avro and the rest survived on their wits, contracts for military aircraft, light sporting types from the late 1920s and civil airliners in penny packet numbers. If Usborne had gone into the administration of civil aviation, he might have prospered there, as did Sefton Brancker and Frederick Sykes. On the other hand many of his airship contemporaries rose to senior rank in the RAF or the Royal Navy; Masterman (1880–1957) and Maitland (1880–1921) were both Air Commodores, Elmhirst (1898–1982) became an Air Marshal, Sueter (1872–1960) a Rear Admiral, and both Bell Davies (1886–1966) and Usborne’s own brother, Cecil, (1880–1951) reached the rank of Vice Admiral. It is safe to say, I believe, that he would have made a lasting mark and would not be such a forgotten figure.

  Appendix I

  Lighter-than-Air Flight Before the Advent of the Dirigible

  In 1766 the English scientist, Henry Cavendish, announced his discovery of the density of inflammable air (or hydrogen as it was later named by Lavoisier) which was lower than that of any other element. By pouring sulphuric acid over iron filings, he was able to collect a sufficient quantity of the gas for his research. (Cavendish (1731–1810) was an English chemist, best known for his experiments on hydrogen, demonstrating its relative lightness compared to air. He announced the results of his research into the specific gravity of inflammable air (hydrogen) in 1766, which led the Professor of Chemistry at Glasgow University, Dr Joseph Black (1728–1799), to suggest the use of the gas for balloons.)