H.M.Balloon Factory No.23
Beardmore No. 24
Armstrong Whitworth No.25
H.M. Balloon Factory R.29
When His Majesty’s Airship No. 9 (HMA No.9) was delivered in the closing months of 1916 it was almost obsolete as a result of the lengthy political vicissitudes that had bedevilled its production. It served a useful purpose, however, it had become the basic pattern on which the four rigid airships for the Admiralty were later to be based. The first of these ‘23’ class airships, HMA No. 23, was subsequently delivered from Vickers Limited, Barrow-in-Furness, to Pulham on 15 September 1917.
Design work had started in June of the previous year, the first flight being planned for that autumn, but considerable redesign had to be carried out when the original specification resulted in a vessel that was something like 3493 kg (7,700 lb) too heavy, the greater part of this excess being attributable to the choice of engines.
The first trial flight of No. 23, four days after delivery, turned out to be something of an anticlimax, for it was clear that she too was at least obsolescent, as might be expected from the original design source, and her modern counterparts had a lifting capacity some nine times greater than that of which she was capable. It is hardly surprising, therefore, that the planned total of 10 airships of this type was finally cut back to six, while No. 23 was relegated to training duties. The other units of the class were HMA No. 24 (Beardmore), HMA No. 25 (Armstrong Whitworth), HMA R26 (Vickers), HMA R27 (Beardmore) and HMA R29 (Armstrong Whitworth), the last pair being of the improved ‘23X’ class without an exterior keel. No. 26 was the first to receive the ‘R’ prefix for rigid airships.
Mindful that in the mid-months of 1918 there was a possibility of aerial confrontations between airships of the opposing nations, experiments were carried out with Sopwith Camel aircraft suspended beneath the envelope of No. 23; the plan in the event of an attack was for the two fighters to be released to defend the mother vessel. There was no provision at the time for the aircraft to be reclaimed.
In the spring of 1919 No. 23 was strengthened for tests at a mooring mast, but before they could be carried out she was broken up in September.
HMA No. 23