Interesting thread, because that's precisely what the German navy used its rigid airships for during the Great War, for naval reconnaissance, although primarily for its surface fleet. The latent threat these airships posed was recognised by the Royal Navy and led to the fitting of high angle guns to its ships and eventually aeroplanes to be flown from gun turrets on capital ships. A Zeppelin, L 23 was shot down by Flt sub Lt Bernard Smart flying a Sopwith Pup launched from the cruiser HMS Yarmouth in August 1917. The superiority of aeroplanes over airships was more than proved during the Great War. If a Sopwith Pup (or even a BE.2c of all things) could shoot down a Zeppelin in 1916 (the year when the first rigid airships were shot down over Britain by BE.2cs), then their use in WW2 would have been entirely wasteful.
large rigid airships required an awful lot of aluminium and and awful lot of labor.
This was the main reason why big rigids were considered a waste militarily even during the Great War. Only the Germans built large numbers of them for military purposes. Although Britain had rigids during the war, it had only a handful and chose to devote its airship effort to non rigids for maritime patrol, at which task they proved relatively successful - as did the US Navy's use of blimps during and after the war in the same role. Militarily, the rigid was a needless waste of money. Non rigids were faster, could respond to submarine threats more quickly from the ground and the air, were easier to handle on the ground and in the air and were significantly cheaper than a rigid airship to build and maintain. For less than the cost of one 23X Class rigid, the British could build three SSZ non rigids, or two bigger, long ranging North Sea Class non rigids.
R29 s
R.29, a 23X Class airship and the only one credited with the destruction of a submarine; the U boat UB 115.
SSZ 59
the Submarine Scout Zero Class SSZ.59 about to land on HMS Furious in 1918.
NS 7 NS 8 sm
The North Sea Class non rigids, NS.7 and NS.8.
The Admiralty calculated that the construction of one airship shed big enough to house a rigid airship cost the same as a dreadnought to build. It wasn't the hydrogen that killed the rigid airship, it was the cost and the logistics of operating them in the face of the cheapness and ease of operating aeroplanes and their ever increasing performance as technology improved.
EF airship facilities
A typical RNAS airship station, with its giant sheds and hydrogen processing plant.
These photos are from my own collection and I have permission to use them from the original source.