Lighter Than Air

by Guy Warner

  The Coastal Class was followed by the improved C Star Class, ten of which were constructed. It was an interim type produced at short notice by the team at Kingsnorth because of problems with the development of the North Sea Class. They were 207 feet in length (63 metres), 217 feet (66 metres) from C*4 onwards, with a maximum diameter of 47 feet (14 metres) and a capacity of 210,000 cubic feet (5943 cubic metres). The streamlined, tri-lobe envelope and the 220 hp (163kW) Renault engine aft, with a 110 hp (81kW) Berliet forward, allowed a faster top speed of 57mph (91kph). The car was clad in plywood rather than canvas, with portholes of Triplex glass to each side and in the floor. Provision was also made for static line parachutes for the crew in case of emergency. The longest flight made by a C* was one of thirty-four and a half hours, made by C*4 in May 1918.

  Coastal Star Class airship C*7, note C*5 in the background. (J.M. Bruce; G.S. Leslie Collection)

  A North Sea Class airship over East Fortune in 1917. (Jack McCleery)

  North Sea Class airship NS4.

  When the North Sea Class had recovered from its teething problems under the care of the Kingsnorth design team, it quickly proved to be the most efficient of the British blimps. The class was once more based on the Astra-Torres tri-lobe pattern, but was larger again, with a length of 260 feet (79 metres), maximum diameter of 57 feet (17 metres) and a capacity of 360,000 cubic feet (10,188 cubic metres). Power came from a pair of 250 hp (185kW) Rolls-Royce Eagle engines, with a design maximum speed of 55mph (88kph), though on occasions modified craft reached 70mph (112kph). Fifteen of this class were delivered before the Armistice, when production was cut short. The car, which contained control, navigation and wireless rooms, accommodation and sleeping space, was completely enclosed and was made from steel tubes clad in Duralumin and fabric. There was also a separate engine car connected by a walkway. The crew of ten were split into two watches, so patrols of several days in duration could be made. There were also cooking facilities on a hot-plate fitted to an engine exhaust. Up to five machine guns could be fitted and six 230lb (104kg) bombs could be carried. When the German High Seas Fleet surrendered and sailed into British waters in November 1918, NS-7 and NS-8, which were based at East Fortune on the Firth of Forth, escorted them in, positioned to starboard and in the centre of the fleet respectively. A world endurance record of 100 hours and 50 minutes was set by NS-11 in February 1919. In March, NS-11 and NS-12 made the first airship flights to Norway.

  Three large non-rigids of the Parseval type were built by Vickers at Barrow and assembled at the airship station at Howden in Yorkshire, and also gave useful service, as did the thirteen SS Twin Class, of which 115 were planned and which were about half the envelope size and two thirds the length of the Coastal Class.

  That their utility was valued throughout the war may be seen from two official documents, the first a memorandum from Captain F.B. Scarlett, DAD, and dated 26 March 1918:

  ‘The following shows the number and types of different airships in commission:

  ‘SS 9; SS Pusher 3; SS Zero 31; SS Twin 1; Coastal 9; Coastal Star 2; North Sea 3; Parseval 3 and Rigid 5.

  Notes

  ‘The SS Type was the first small airship commissioned, motive power supplied by one 75 hp engine. This type is now used for training.

  ‘The SSP Type is a slight improvement on the former.

  ‘The SSZ Type, which is in extensive use on most of the airship stations, is a decided improvement on the two foregoing types, and has proved extremely useful for anti-submarine patrol.

  ‘The SST Type is similar to the SSZ, with the exception that it has two engines and is known as the SS Twin. The first unit of this type has just undergone its trials, which were extremely promising, the extra engine giving this ship a greater speed and making it much more reliable in case of engine failure.

  ‘The C Type ship, known as the Coastal Patrol, will very probably be superseded by the SS Twin, although it has been extremely useful for patrol work.

  ‘The C Star Type is an improvement on the C and has not been commissioned very long.

  ‘The NS Type ship, known as the North Sea type, was designed for the purpose of doing extensive patrols in the North Sea, but up to the present has not given very good results.

  ‘The P ship is the original German Parseval type.

  ‘The R type ship is known as the Rigid and has been constructed on the lines of the German Zeppelins. These ships should still be considered as experimental.’14

  The second is a planning paper written for the Board of the Admiralty, setting out airship requirements in the event that the war continued into 1919:

  ‘In pursuance of Minute 354, the committee have reviewed the situation with regard to Rigid and Non-Rigid Airships, and they have agreed upon the following report and recommendations:

  Non-rigid Airships

  ‘In connection with the approved programme for completing 115 SS Twin-Type airships by June 1919, the committee found that the experiments with the Sunbeam Dyak engine, referred to in their previous report, have been successful, and that the Air Ministry are arranging to have this class of engine built for the Admiralty by the firm of Messrs Sunbeam. The delivery of this engine will commence in December, some months earlier than was anticipated, but on the other hand the dates for delivery of Rolls-Royce Hawk engines indicated in the previous report of the committee have been somewhat deferred.

  ‘The approved programme of SST airships should therefore ensure the completion, by the end of June 1919, of 117 airships (including two experimental) which, with fifty-eight SSZ in commission and one in reserve, and thirteen SS and SSP airships (that is 189 in all), and allowing for a deletion of six for obsolescence, but making no allowance for casualties, would give us a stock of 183 airships from 1 July next.

  Rigid Airships

  ‘The committee found that the dates for the completion of rigid airships as indicated in their previous report had not been, and, cannot be realised, owing to difficulties in regard to construction and trials, shortage of labour, and in some cases alteration of design. By Board Minute 354, the number of rigid airships to be maintained in commission has been reduced to eleven, so that no further housing accommodation for rigid airships is required beyond that at present existing and in course of construction at Howden in Yorkshire and Killeagh in Co Cork, Ireland.

  Generally

  ‘The committee recommend that in future the situation with regard to rigid and non-rigid airships should be reviewed by them at intervals of three months, when account will be taken of any further orders rendered necessary by casualties which have occurred during the previous quarter.

  Summary

  ‘The report of the committee may be summarised as follows:

  1. ‘That the approved programme of SST airships should ensure the completion, by the end of June 1919, of 117 Airships (including two experimental) which, with fifty-eight SSZ in commission and one in reserve (obtainable by utilising large spares already in stock), and thirteen SS and SSP airships (that is, 189 in all), and allowing for a deletion of six for obsolescence, but making no allowance for casualties, would give us a stock of 183 Airships on 1 July 1919.

  2. That no further housing accommodation will, prior to 1 October 1919, be required either for rigid or non-rigid airships beyond that already existing or approved.

  Recommendations

  1. ‘That a further forty-eight SS Twin airships be now ordered for delivery in July, August and September 1919, in order to maintain continuity of production and to allow for casualties.

  2. ‘That no further large spare parts be ordered for SSZ Type, and that this type of vessel be allowed to die out as existing large spares are used up.

  3. ‘That the SS and SSP type be maintained as necessary by minor repairs only, and that they be allowed to die out when it becomes necessary to use large spares.

  4. ‘That non-rigid airships lost, prior to 1 October 1918, be made good from stock, but that subsequent to that date, ships completely l
ost be struck off the establishment, and ships partially destroyed, of which any material part remains, be replaced out of spares.

  5. ‘That the situation with regard to both rigid and non-rigid airships be reviewed by the committee at intervals of three months.’15

  No other contemporary aircraft could have performed the jobs airships undertook. None could match the airships’ endurance or slow speed capability. They could stay close to the convoys and their escorts for extended periods; either scouting ahead for submarines or mines, or standing off to windward, ready to swoop down rapidly to investigate a possible threat. Indeed, it could be said that the airships’ potential was, even by the later stages of the war, not fully appreciated. Those operating with the Grand Fleet were sent ahead on scouting missions, but were forbidden by the C-in-C, Admiral Beatty, to go beyond visual range of the leading vessels, thus not breaking radio silence, but greatly limiting their range of vision over the horizon.

  Another limitation imposed on the use of airships was described by Rear Admiral Murray Sueter, when he revealed in a book published after the war that he had proposed to the Admiralty in 1915 a scheme for the extensive aerial surveillance of shipping to be carried out by airship in the Mediterranean. This was turned down on the grounds of cost and in Sueter’s opinion prevented the solution to what became a very costly destruction of shipping in that theatre.16 He made this summary of the RN Airship Service’s contribution in World War One, which had grown in size to 580 officers and 6534 men at eighteen airship stations:

  On 1 November 1918 there were 103 airships in commission, five rigids, one Parseval, six North Sea, ten Coastal Star, four Coastal, twelve SST, fifty-three SSZ, three SSP and nine SS.18 It should be noted that in the course of this valuable service only fifty-four airshipmen lost their lives from all causes. Sixteen airships in total were lost, mostly through accident or mishap. The most intense part of the campaign was from June 1917 to October 1918. During these sixteen months, on average, fifty-six airships were on duty every day and a total of 9059 patrols were carried out, the average duration of which was six hours and seventeen minutes. A total of 59,703 hours were flown, including 2210 escorts of shipping; 134 mines were sighted, of which seventy-three were destroyed; forty-nine U-boats were spotted, twenty-one of these were attacked with the help of surface craft and six by airships on their own. Their deterrence value was immense – during the entire war there was only one instance of a ship being escorted by an airship being sunk. This may be placed in context by considering the fact that of the 12,618,283 tons of merchant shipping lost in the First World War, 11,135,460 tons were sunk by U-boats – eighty-eight per cent of the total. During the final fifteen months of the war, SS type airships carried out over 10,000 patrols, flying nearly one and a half million miles in more than 50,000 hours. The submarines were kept below the waves, where they used up valuable battery power and were restricted to a speed of only eight or nine knots. A brief log entry from a captured U-boat speaks volumes; ‘Sighted airship – submerged.’ An analysis written in a respected, post-war, monthly magazine noted:

  ‘The Germans stated that what they disliked most in the Irish Sea area were the airships that were always passing over them. They did not fear the bombs these craft carried, but they did dislike having their own position continually reported to the surface patrols, who, as a result, gave them little rest. There is no doubt that the morale of submarine personnel is much affected by continual nerve strain.’19

  The Royal Navy’s non-rigid airships did not win the battle against the U-boats on their own, but they made a highly important and unique contribution, without which the struggle would have been much more difficult. It was; ‘An instrument of knowledge rather than power.’20

  There is a remarkable consensus of opinion between contemporary commentators, politicians and airshipmen, as well as historians in later years. There is not a single dissenting voice, all agree on the utility, effectiveness and value for money of the naval non-rigid airships. Within a few months of the cessation of hostilities most of the non-rigids were withdrawn from service, as the RAF contracted hugely, and financial pressures bit into the budget. They were used extensively in mine-clearance operations, but by the summer of 1919 most had been deflated for the final time. The last non-rigid to serve with the RAF was NS-7, which was based at Howden in 1920, training the crew of R38. It flew for the last time on 25 October 1921.

  It was to the airships’ advantage that they operated in an environment without predators or effective countermeasures; there were no aircraft carriers to bring fighter aircraft within range and the U-boats were not equipped with antiaircraft armament, nor did they really wish to remain on the surface and fight it out. Experimental use was made of SSZ1 in towing trials with the Lord Clive Class monitor, HMS Sir John Moore, off Dunkirk in 1916. The plan was to see if the airship could be used to spot for the monitor’s 12 inch (304mm) guns as it bombarded German positions. It was quickly realised that the slow speed of the airship made her employment that close to the enemy coast impracticable. Another airship, SS-40, served briefly on the Western Front from Boubers-sur-Canche, near Arras, in the summer of 1916; she had a larger envelope, which was painted black. On a trial flight from Polegate it was noted by the War Office acceptance team; ‘The ship became invisible as soon as she took off; seemed to go round in a circle and fade away. Never saw her again till she landed. Very good show!’ However, in France, the results were disappointing as the Black Ship, or Bertha the Black Blimp, as she was known, could only operate safely at night, when there was little that could be seen, so the experiment was abandoned after only two flights. Or was this merely a cover story? Interestingly, the memoirs of one airship pilot, relating to his time at Kingsnorth, refer to SS-40:

  ‘Disappearing from time to time, she was used for night work over France, dropping men behind the lines.’21

  SS-40: The Black Ship.

  This is corroborated to an extent in a memoir by Air Marshal Sir Victor Goddard in preparation for a talk on the BBC in 1955, which was never broadcast:

  ‘Many’s the time that the Black Ship sailed over the lines at night through that long summer and autumn of rumbling, bloody battle. But never once with an agent to drop. Spies are brave men, but they didn’t fancy our airship as a mode of travel. Instead, Flight Sub-Lieutenant Billy Chambers and Captain C.R. Robbins made night reconnaissance from which all too little could be learned about the enemy’s movements. Coming back from a clandestine operation, the crew of the Black Ship would sing a bawdy song as they approached their hangar at treetop height, with the engine throttled back. The singing was to alert the ground crew and also to discourage any Tommies below from taking pot shots at the almost silent shape. Chambers was mentioned in dispatches in General Haig’s report on the Battle of the Somme.’22

  Despite this hint of cloak and dagger work it can be said that the technology was only able to survive in the context of the conditions pertaining between 1914 and 1918, or was it?

  To war with the US Navy (Twice)

  A small number of blimps were used for coastal patrol duties by the US Navy in 1917–18. An assortment of small non-rigids of various sizes was maintained by the US Army, and then exclusively the navy, between the wars. The major operator in the inter-war period was the Goodyear-Zeppelin Corporation of Akron, Ohio, which built the following small, helium-filled, non-rigid airships, including Pony (1919–23), Pilgrim (1925), and the extended fleet of the later 1920s and early 1930s: Puritan, Volunteer, Mayflower, Vigilant, Defender, Reliance, Resolute, Rainbow, Enterprise, Ranger and Columbia. A typical example would have been 140 feet (42.67 metres) in length, with a diameter of 40 feet (12.19 metres), a volume of 112,000 cubic feet (3169 cubic metres), driven by two 110 hp (81.4kW) engines, giving a speed of 60mph (96kph) and the ability to carry six passengers. By 1942 they had made 151,810 flights, 92,000 flying hours, with a total distance of more than 4,000,000 miles (6,437,000 kilometres) in every state east of the Mississippi, but als
o to Texas, California, Cuba, Canada and Mexico, carrying 400,000 passengers in complete safety. Their versatility was immense: delivering mail and newspapers, taking aloft press reporters, newsreel cameramen and radio announcers to report on sports and other events, facilitating wildlife, civil engineering and traffic studies, disaster and emergency relief, rescues from the Everglades and at sea, and pleasure flights, to list just some of the roles for which they were used.23 The pilots, crew and ground staff gained vast experience operating their craft in all weathers and became very confident with the ability of their ships to fly in all but the most adverse of conditions. Perhaps the worst hazards were the attentions of trigger-happy and thoughtless hunters, which at least proved that the blimps could sustain bullet damage and fly on. Many of the Goodyear pilots were commissioned as reserve officers in the USN, giving a nucleus of experience from which the naval airship service could expand. As for the Goodyear blimps, they had naval markings applied and were pressed into service for training duties.

  A Goodyear blimp lands at the Century of Progress Exposition held in Chicago in 1933–34.

  The Goodyear fleet at Akron.

  USN blimp G-1.

  USN blimp K-3.

  In 1941 the US Navy had a handful of blimps. After the attack on Pearl Harbour in 1941, the Navy asked the US Congress for authorization to purchase many more. By June 1942 the construction of 200 helium-filled airships had been authorized. During the next three years Goodyear built a total of 168. At its production peak, the company was turning out eleven airships monthly. The United States was the only power to use airships during World War II, and the airships played valuable roles. The USN employed them for minesweeping, search and rescue, photographic reconnaissance, scouting, escorting convoys, and anti-submarine patrols.