As always, click the pictures to enlarge. Postcards by W. H. Applebee, John Drew and Mays.
Beta was completed in May, 1910. The envelope was that of the Baby enlarged, and now had a volume of 35,000 cubic feet. The car was composed of a long frame, having a centre compartment for the crew and engines, which was the standard practice at that time for ships designed by the Astra Company. A 35 horse-power Green engine drove two wooden two-bladed propellers by chains. The ship was fitted with an unbalanced rudder, while the elevators were in the front of the frame. This ship was successful, and in June flew to London and back, and in September took part in the Army manoeuvres, on one occasion being in the air for 7 3/4 hours without landing, carrying a crew of three. Trouble was experienced in the steering, the elevators being situated too near the centre of the ship to be really efficient and were altogether too small.
In 1912, Beta, having been employed regularly during the previous year, was provided with a new car having a Clerget engine of 45 horse-power. In 1913 she was inflated for over three months and made innumerable flights, on one occasion carrying H.R.H. the Prince of Wales as passenger. She had at that time a maximum speed of 35 miles per hour, and could carry fuel for about eight hours with a crew of three.
In 1910 the Gamma was also completed. This was a much bigger ship with an envelope of 75,000 cubic feet capacity, which, though designed in England, had been built by the Astra Company in Paris. The car, as in Beta, was carried in a long framework suspended from the envelope. This portion of the ship was manufactured in England, together with the machinery. This consisted of an 80 horse-power Green engine driving swivelling propellers, the gears and shafts of which were made by Rolls Royce. The engine drove the propeller shafts direct, one from each end of the crankshaft.
Originally the envelope was fitted with inflated streamline stabilizers on either side, but at a later date these were replaced by fixed stabilizing planes. At the same time the Green engine was removed and two Iris engines of 45 horse-power were installed, each driving a single propeller. There were two pairs of elevators, each situated in the framework, one forward, the other aft. In 1912, having been rigged to a new envelope of 101,000 cubic feet capacity, the ship took part in the autumn manoeuvres, and considerable use was made of wireless telegraphy.
In a height reconnaissance the pilot lost his way, and running out of petrol drifted all night, but was safely landed. When returning to Farnborough the rudder controls were broken and the ship was ripped. In this operation the framework was considerably damaged. When repairs were being carried out the elevators were removed from the car framework and attached to the stabilizing fins in accordance with the method in use to-day.