User:TheLongTone/Zeppelin Class T

The V Class Zeppelins were a type of bombing and naval patrol airship produced by Zeppelin Luftschiffbau during the World War 1. They were designed to be capable of operating at an altitude that would put them beyond the reach of defensive aeroplanes and anti-aircraft fire. A total of nine airships of the intermediate S, T and U Class designs were produced before the definitive "height climber" V Class, of which ten were built, flew in August 1917. Operation at increased altitudes proved problematic and they were unsuccessful as bombers, although their increased altitude did increase the safety of their patrol work over the North Sea.

Background
Following the destruction of several Zeppelins during 1916 by the increasingly effective British defences, the German navy made a reassessment of the operational requirements of their airship fleet. The German Navy Ministry favoured the development of more powerful craft capable of higher speeds but with the same ceiling, but Peter Strasser, the commander of the German Imperial Navy Zeppelin sevice, favoured a different approach, believing that airships capable of bombing from an altitude that would put them beyond the reach of defending aeroplanes were necessary. This was to be acheived by reducing the number of engines from six to five and making the hull framework lighter. At the end of January 1917 a conference was called by the head of the Dockyard Bureau, and Strasser's proposals were accepted.

Intermediate types
Immediately after the conference the four newest R Class Zeppelins were modified by removing the bomb racks on the port side and one engine from the aft gondola, effecting a weight saving of 4070 to 4890 lb. Preliminary trials demonstrated a substantial increase in ceiling, and two R class Zeppelins already in production were finished with these modifications as S Class Zeppelins. The defensive armament was also omitted, and to make the airship less visible the undersurfaces were painted black. The first, LZ 42, was commissioned on 28 February and on 10 March succeeded in reaching an altitude of 19700 ft during a height trial.

On 1 April the first of two T Class Zeppelins, L 44, was flown. This had lightened hull framing and a redesigned streamlined aft gondola, with the engines driving a single pusher propeller. The second example, L 46, also had newly designed streamlined midships engine cars. The U Class, of which five were built, introduced a smaller and lighter control car, further reducing weight by 2430 lb

Class V
The V class combined the refinements of the S, T and U class ships with a completely new hull design, which had the main transverse ring frame spaced 15 m apart, with a pair of intermediate frames in each bay. This reduced the number of gasbags from eighteen to fourteen. . These modifications to the design both lowered the weight of the airframe and also increased gas capacity by about 7000 ft3. The first example built were powered by the Maybach HS Lu engine, which suffered from loss of power at altitude owing to lack of oxygen, reducing maximum speed from 60 to 45 mph. This had been foreseen and a new engine, the Maybach Mb IVa was under development. This had oversize cylinders and could not be run at full throttle below 5900 ft. The first Zeppelin to be fitted with this engine was L 58, which could reach 67 mph at sea level and 60 mph at 19700 ft. The existing Zeppelins were retrofitted with the new engine. The last example built, L 65, had cantilever tail surfaces with little external bracing. was developed, but this did not come into service until November 1917. The first V class, LZ 100 (L 53), flew on 8 August 1917. A total of 10 were built.

Class W
The W class was lengthened version of the V class intended to carry out a mission to resupply the German forces in East Africa. The hull had two extra bays added to accommodate two more gasbags, increasing the length to 743 ft and capacity to 2418700 ft3. The specially built LZ 102 was destroyed before it had finished trials, and LZ 104, a Class V Zeppelin already under construction was completed as a W class.

Class X
The X class was the final Zeppelin design to be built during the war, and was a development of the V class, lengthened to accommodate an extra gasbag, giving a length of 211.51 m (693 ft 11 in) and capacity of 2195800 ft3 and powered by seven engines, the two extra engines being carried in a second pair of engine cars either side of the hull. It was armed with a pair of Becker 20 mm cannon mounted in the control car and was intended to be able of carrying 10500 lbs on lower-level bombing raids or 6600 lbs when bombing from high altitude. The extra power gave L 70, the first example constructed and first fown on 1July 1918, a maximum speed of 81 mph. The second example built, L 71 was lengthened after completion to accomodate a sixteenth gasbag, resulting in a length of 226.52 m (743 ft 2 in) and capacity of 2418700 ft3: at the same time the aft gondola was replaced by a smaller unit containing a single engine. The third example constructed, L 72, was completed to this specification.

A myth has arisen that L 72 was intended to bomb New York: this originated with a conversation between Ernst Lehmann and Colonel William Hensley of the US Army, who was visiting Freidrichshafen with a view to purchasing a Zeppelin for the US Army. Hensley uncritically believed Lehmann's boast.

Operational history
High-altitude operation proved problematic for a number of reasons. At the time the extent to which wind conditions at high altitudes could differ from those encountered at lower levels was not appreciated, and the German weather forecasting balloons only gathered data at relatively low altitudes.

Increased altitude also made navigation more difficult, with the airships often entirely reliant on radio direction-finding. Until 1918 the system used by the Germans involved the Zepelins sending signals which were received by ground stations who would work out their position. If more than a few airships were in the air the system became overloaded.

The flight crews suffered from lack of oxygen and the extreme cold, both of which severely reduced their efficiency. Initially compressed oxygen was supplied, but the crews considered it a sign of weakness to use it, and only began to use it when their commanding officers began to make its use compulsory. However, the oxygen supply was often contaminated by oil or glycerine, leading to stomach probems, and it also tended to leave users with cracked lips and hangover-like symptoms. Later, liquid air was substituted for pure oxygen, with more satisfactory results.

icing and freezing of ballast water and even the fluid in the compasses. Furthermore the venting of hydrogen made necessary by the greatly reduced atmospheric pressure at high altitude led to a problem caused by limited hydrogen production and storage capacity. Each mission entailed the loss of around 28,000 cu m (1,000,000 cu ft) of hydrogen. The hydrogen generating plant at the base at Nordholz had a capacity of 43,000 cubic metres (1,520,000 cu ft) per day, with storage for another Low-pressure storage 30,000 cubic metres (1,060,000 cu ft) usable capacity High pressure storage 180,000 cubic metres (6,340,000 cu ft).

The first raid over England using the modified R class airships was carried out on 16 March by L 35, L 39, L 40, L 41 and L 42. Carrying bomb loads of between (35-4,000 lbs the Zeppelins encountered unexpected high winds, which their reduced engine power.

Also cloud cover made navigation difficult, and none of them bombed London: the nearest place to London that was bombed was Canterbury. The winds made the return trip difficult. Three managed to return. L 40 was severely damaged on landing and L 39, probably suffering from failure of one or more engines, was blown over Allied territory and shot down in flames by antiaircraft fire near Compiègne.

A second attack on London on 23-4 May also failed, with no bombs falling closer than Braintree in Essex. On 16-17 June a six-Zeppelin raid was planned, but two were unable to leve their shed because of wind and two others turned back because of engine failures. The S-class L 42 succeeded in bombing an ammunition store in Ramsgate, but L 48, the first U-class, was shot down after being attacked by  several aircraft: Lieutenant Pierce Watkins, flying  a B.E. 12 was credited with the victory. The Zeppelin had made landfall near Orfordness and with two engines not working, had attempted to bomb Harwich rather than attempting to reach London and had ten reduced altitude to exploit an expected tailwind at lowere altitude, and was flying at about 15000 ft. . The Zeppelin came down near Theberton: uniquely, three members of the crew survived the crash, altough one of them died of his wounds on Armistice Day, 11 November 1918.

On 27 July 1917 General Ludendorff proposed that all airship production should cease in order to conserve strategic resources such as aluminium and rubber for aeroplane construction. Admiral Scheer insisted that Zeppelins were essential for naval scouting duties. After referring the matter to the Kaiser, Zeppelin production continued, but the rate of production was reduced from two a month to one every two months, and it was ordered that in general the airships were only to be used for scouting.

The last major airship raid on England, which became known as the "silent raid", was launched on 19 October 1917, when 11 Zeppelins, including two V class, set off to bomb targets in the Midlands. The raid killed 36, injured 55, and caused £54,346 material damage but resulted in the loss of five Zeppelins, victims of engine failures and adverse weather: despite a favorable weather forecast the airships encountered winds of over 45 mph at altitude. The wind dispersed the Zeppelins and blew them considerably off course. The T class L 44, probably suffering from failure of some of its engines, was blown over French territory and shot down by antiaircraft fire near St. Clément and L 49, also suffering from engine failure, was forced down by French fighters near Bourbonne-les-Bains. The crew were unable to set fire to the Zeppelin, and a detailed examination was made of the design: this would contribute greatly to the design of the American USS Shenandoah. The modified R class L 50, similarly blown off course and disabled, was deliberately flown into the ground by its commander at Dammartin. The impact tore off the forward gondola and sixteen of the crew escaped from the airship and survived, but four crew members remained on board as the lightened craft lifted off: it was blown south, crossing the coast near Fréjus and presumably came down in the Mediterranean. L 45, also a modified R class, was blown south of its intended targets and caused much of the damage caused by the raid by dropping three 200 kg (660 lb) bombs on London, one falling in Picadilly. L 55, short of fuel and unable to regain its base, crash landed and was damaged beyond repair.

The U class LZ 97 (L 51) and the V class LZ 105 (L 58) were among the 5 airships lost in the explosion at the airhip base at Ahlhorn on 5 January 1918, and on 19 July 1918 the U class L 50 and the V class L 56 were burnt in their shed as a result of being bombed during the Tondern Raid.

On 6 August L 70, the first example of the X-class Zeppelins, accompanied by four V class zeppelins (L 53 L 56 L 63 and L 65) took part in the last bombing raid of the war. Again poor weather forecasting played an important part in events: a headwind had been expected but was not as strong as expected, resulting in the airships arriving within sight of the English coast before darkness fell. L 70, with Peter Strasser on board, was intercepted and shot down by a D.H. 4 flown by Egbert Cadbury, and L 65 was also damaged. No bombs fell on English soil.

On 11 August 1918 L 53, the first V class to enter service, was shot down while on a naval patrol by a Sopwith Camel flown by Lieutenant S. D. Culley flown from a lighter towed by HMS Redoubt. Redoubt was part of the escort for a force of torpedo boats sent to attack German shipping near Terschelling. The airship, patrolling at around 19000 ft, spotted the escorting force and investigated, but had been spotted and launched the Camel at 08:58. The climb to the altitude at which the Zeppelin was flying took about an hour, but eventually Culley was able to position himself around 300 ft below the Zeppelin and empty a double drum of inceniary and explosive ammunition into it, setting ot on fire.

The U class LZ 98 and the V class L 63 L 65 were wrecked in their sheds on 26 July 1919 by their crews.

The V class L 64 and the later X-class L 71 were handed over to the United Kingdom as war reparations. Both were flown by German crews to Pulham Airship Station in June 1920, where they remained in storage until 21 June 1921, when they were hastily broken up in the shed in order to house the British airship R36, which had been damaged while being moored and urgently needed to be housed.

The third X class, L 72, was not completed until after the end of the war, and was given to France as war reparation and, renamed Dixmude, taken into service by the French Navy. Delivered in August 1920, it remained in storage for three years since its gasbags had deteriorated and needed to be replaced: the French elected to manufacture the rplacements themselves, but initially did not have the manufacturing capacity. It made a number of flights in 1923, including several crossings of the Mediterranean to Tunisa, before being lost when it exploded in mid-air on 21 December 1923 off the coast of Sicily probably after being stuck by lightening killing all 52 (42 crew and ten passengers) on board.