controls proved both light and effective, and its control characteristics were compared favourably with those of R101 by Nöel Atherstone, First Officer of R101. R100 was built suspended from the roof of its shed. The individual transverse frames were assembled horizontally then lifted up and slung from roof-mounted trackways before being slid into position and attached to the adjacent frames by the longitudinal girders. The ship remained suspended until the gasbags were inflated with hydrogen. By mid-1929 the ship's structure was nearly complete and its gasbags were inflated. Following inflation of the gasbags, the outer covering of linen fabric painted with aluminium aircraft dope was put in place, and it was completed at the beginning of November. Lift and trim trials were carried out on 11 November: empty weight was and gasbag volume was , giving a standard gross lift of and so a disposable lift of . Deducting for the service load (crew, stores and ballast) this meant the weight available for fuel and payload was . Propulsion It had originally been intended to design special engines for R100 which would be fuelled by hydrogen and kerosene but after a year's work it was realised that the engine would not be developed in time and it was decided to fit the Beardmore Tornado diesel engine that was being developed for the Air Ministry for installation in R101. At an early stage the Tornado was judged unsuitable because of its weight and other problems, and Wallis settled on the use of six reconditioned Rolls-Royce Condor petrol engines even though the fuel, with its lower flash point, was considered to be a fire risk under tropical conditions. The engines were contained in three gondolas, each with one engine driving a 17 ft (5.18 m) diameter tractor propeller and a second driving a 15 ft (4.57 m) diameter pusher propeller. The engines driving the pusher propellers were fitted with a gearbox to provide reverse thrust for docking the airship. Passenger and crew accommodation The passenger and crew accommodation were arranged on three decks occupying a single bay of the structure and entirely contained within the airship's envelope. The lower deck contained the crew accommodation. The second deck had a dining room, which doubled as the passenger lounge, plus the kitchen, 18 four-berth passenger cabins and a gallery on either side for passengers to enjoy the view through the windows built into the