Post by belov1 on Jun 16, 2008 3:32:27 GMT -5
British commercial airship program
Sic transit gloria mundi
At the middle of the 20-th years of the XX century wide possessions of British Empire were connected only by sea communication lines. Comfortable but slow liners take weeks to steam from London to Melbourne or Montreal. Telegraph or telephone cannot fulfill all requirements of communications between metropolis and widespread dominions and colonies.
Aircrafts were small, smelly, uncomfortable, noisy and, in some cases, extremely draughty. In the 1920s, they were not a serious contender to carry passengers on medium- or long-distance flight. The airship had much to offer.
In 1924, the Government agreed to establish aerial communication links with the far corners of the Empire. The decision was made to construct two entirely new airships to serve air routes to Montreal, Canada, and Karachi, India, with the final view to have a ship to reach Australia. A plan was also made that the ships could be of a military value to have the ability to carry some 200 troops or 5 airplanes. Whoever it was deemed that a ship of some 8,000,000 cubic feet would be required. However it was agreed to continue with the non military version of the ships. The original plans by 1926 were to have routes from Canada to Australia with a regular connecting service and stops en route. It was decided, that 6 airships would be enough to cover this service.
To serve Imperial Airship communications, mooring masts were constructed at Montreal, Ismalia in North Egypt and Karachi in India. Sites at Durban, Mombassa, Cape Town, Pert, Melbourne and Wellington were planned.
Following criteria were taken into consideration for airship base construction.
It follows from this that a site for an airship base should be selected as nearly as possible at sea level, since if an airship base is situated, say, 2,000 feet above sea level, the airship on leaving would halve less useful lift for freight. For the same reason the base should, if possible, not be sited so as to necessitate flying over mountain ranges at the outset or in the early part of the journey, since the ascent can only be made by reducing the load of the airship which is uneconomic from the operating point of view. On the other hand when an airship has been flying for some time and has thus used up a certain weight of fuel, an increase of height can be gained without the same loss of useful load. Due regard should also be paid to weather conditions, especially in choosing a site for a shed base with docking facilities, where an airship may have to be man-handled into the shed. They are not of so great consequence for an inter- mediate base with mooring mast only, as the airship would always be flown from the mast and not handled on the ground. At the same time local meteorological conditions might affect regularity of service; thus a locality in which thunderstorms are prevalent would generally be unsuitable. It was on account of climatic conditions that the shed base for India was sited at Karachi, leaving the question of bases at Bombay and Calcutta to be discussed later. In the immediate vicinity of a base there should be no obstruction such as hills, high buildings, etc., and any high masts for wireless telegraphy or meteorological purposes should be located as far as possible from the mast and shed, so as not to be a source of danger to an airship landing or leaving.
An airship site must be provided with mooring mast, capable to withstand the pull of the airship up to 30 tons in any direction under wind, hydrogen plant to refill and inflate airship gasbags, workshops and fuel storage, wireless and telephony communications. Of course, airship sheds were to be constructed at first at most important points only.
Thus, at the first stage, only four bases were built.
Cardington, Bedfordshire:
Ismailia, Egypt:
Karachi, British India:
Montreal, Dominion of Canada:
There would be two airships designed and built, one by private contractors, the R100, and one by the government's Royal Airship Works at Cardington, the R101. The Government team had all the data the government agencies could provide. A subsidiary of Vickers, the Airship Guarantee Company, was awarded the private contract and the R100 was built at Howden in Yorkshire. Barnes Wallis led the design team.
For some reason, there was an element of competition here, with the government ship in the forefront. The Labour government may have been trying to prove the superiority of their philosophies over the established system - it certainly seemed that way. The project survived through two changes in government but there were, once again, changes in policy and priority. Although the R101 team knew all about the R100, the reverse was quite different. Vickers did their own wind tunnel and structure tests and sent the results to a central aerodynamics data office. They got most of their information about the R101 from the newspapers.
R100 was ready first. After the trial flights and flights checking the outer cover ripple effect, the ship was tasked with a trip to Canada, successfully crossing the Atlantic to Montreal to the newly erected mast.
The ship slipped the moorings from the Cardington mast at 02.48 in the morning of the 29 August 1930. The ship flew over the Atlantic and headed down the Newfoundland coast to Montreal, arriving on the 1 August at 05.37am, after a voyage of some 78 hours and 49 minutes; a journey of 3,364 miles. The crew were deemed heroes for this voyage. The crossing was not as smooth as predicted when the ship encountered a rough storm flying towards the Canadian coast, causing a ripping to some of the outer cover. Temporary repairs were made in flight and then the cover was replaced at the mast at Montreal.
The crew enjoyed banquets and receptions in their honour. It was seen that this trip would be the start of many crossings and the start of commercial operations. On the 13 August 1930 the R100 was required to go on a "local" flight where it was received excitedly by all the towns she crossed over. On the 16 August 1930 R100 made her return to Cardington and, making use of the gulf stream, managed to knock off some 21 hours off the outward bound flight time, arriving on 16th August 1930 at 11.06am after 2,995 miles and a trip of 57hours 56 minutes.
On her return to Cardington she was then put into the shed for inspection and attention switched to the R101's flight to India, which was anticipated to be at the end of the year. Because many of the crew members were actually operating on both ships, the majority were transferred over to the R101.
The first leg of the final flight route as planned:
Bedford - London - Kent - leave cost over Hastings - North Paris - West to Rhone Valley - Toulouse - over the sea at Narbonne - across Mediterranean - Malta - Ismalia (Egypt).
After this success, the R101 needed another flight to prove it the better airship. It was to fly to India, leaving England for Karachi on the 4 October, 1930, and returning by the 18 October, 1930. Lord Thomson, the then Secretary of State for Air, would be one of the passengers. On the evening of 4 October, 1930, the R101 lifted off in bad weather, which soon became worse. Battling against a headwind, she wallowed for seven-and-a-half hours and flew only 220 miles (350 kilometers). Passing over the French coast, her height was estimated at just 300 feet (90 meters). The reason why this happened is unclear, but the pressure of the headwind may have affected the R101's altimeter, giving a false reading.
She was over Beauvais, when she started a steep dive, pulled up, dived again and hit the ground. She bounced, but then fell a second time, breaking at the point where the lengthening had been added. Sparks from a severed electrical cable were thought to have ignited the hydrogen, which destroyed her completely. All the passengers who were in their cabins were killed; only six crew members survived out of the 54 carried. The official report blamed the collapse of the forward gasbag, which was caused by a failure in the fabric covering of the envelope nose. Real cause of this disaster was never cleared. This may have been because most of the design team were on the R101 as passengers and died with her.
Whatever the reason, the disaster almost ended Britain's airship development. The passengers on the R101 were the champions of the Imperial Airship Scheme and it died with them. The R100, the success story of the venture, was overshadowed by the R101 disaster. She was returned to the shed, deflated and stored. When the scheme collapsed, there was no use for the R100 and she was sold for scrap, bringing just £450. Dismantling began in November 1931 and was completed in February 1932.