Sir - There is something wrong in the Zeppelin comeback feature (Flight International, 29 November-5 December 1995) - at 72lb/in2 the airship would explode.
DAVID MORRELL
London, UK
Sir - I enjoyed the airship articles, but rigid internal He-pressure is not 72lb/in2- it is 27lb/in2 (or 1.88bar).
H O RUPPE
Munich, Germany
Source: Flight International