AC engines for the R100 airship

[Old Crock]

Some subscribers and readers to the forum may not know that in 1927 the AC company supplied engines for the government-funded R100 airship project. The engines were used to run the auxiliaries (the main engines were six Rolls-Royce twelve-cylinders!)
   
   Here's a photo, with interesting caption, from the archives of 'Flight' magazine (issue 13 Oct 1927) showing the familiar AC-6, in vintage form with its single updraught carb, cam-driven waterpump etc.
   
   

[ACOCArch]

quote:Originally posted by Old Crock
   
Some subscribers and readers to the forum may not know that in 1927 the AC company supplied engines for the government-funded R100 airship project. The engines were used to run the auxiliaries (the main engines were six Rolls-Royce twelve-cylinders!)
   

   
   Great photograph, taken in the Ferry Works I believe.
   
   There is an account of the use of AC's Light Six engine in R100 in the Simpson Interview published in the Dec 2002 ACtion Archive. An extract from this is presented below.
   
   "...... The Company had always been prepared to take on a variety of outside work to earn an honest shilling and during the Kaiser war had made Le Rhône engine parts and later the Pobjoy radial aero engine. In the same vein, after the liquidation, two engines were initially supplied for the R100 airship and later a third as a spare for the flights to and across Canada. They were used to drive generators on the ship, chosen no doubt for their power/ weight/cost ratio.
   This led to an adventure for Simpson and Joyce's ex mechanic Malkin. It had been arranged for one of these airships to take a party of MP's on a tour of Britain but on the eve of the big day, amidst the last minute preparations at Cardington, one of the generator motors was overheated and ran its bearings. Our two heroes were despatched from T.D. in response to the ensuing SOS complete with tools and spares and not a little misgivings about the intense cold -it was January and well below freezing - airships in general, and the fact that only mechanics under 5ft 8 ins were employed by the ministry on these craft. Both men were larger than this.
   By the tirne they had covered the sixty odd miles to deepest Bedfordshire, it was dusk and the lift to the top of the mooring mast some hundreds of feet up was broken so they began with a long climb, clutching their tackle, followed by a hair raising scramble across a whippy plank into the nose of the ship as the fabricated tunnel for VIP boarding had not been finished either. Once within, the route was up the central gangway, then third or fourth turning to the right, out to the side of the envelope where jackets had to be removed to squeeze out through a fox hole, down a ladder and into the auxiliary power unit gondola.
   The AC engine was mounted with its sump protruding into the airflow to aid cooling so it had to be raised up and lowered onto its side, leaving a gaping black hole which they avoided falling into at all costs! Even the loss of a tool there would have cost at least a half hour in recovery. The fitting took all night in those conditions and upon completion they learned a few more details of airship design. Like the fact that the AC power units relied upon the cooling blast from the propulsion unit ahead, which relied upon the unit ahead. Indeed only the front engine on each side was truly self sufficient when stationary.....
   ".....When the third engine was ordered from the newly installed Hurlocks at the High Street works they no longer enjoyed the facility of a test bed, since the old one had been at Ferry Works and the new one was yet to be built. Yet the Ministry inspector had to approve it running so it was dropped into the works van and driven  about to prove the point......
   
   I have not been able to find any further information about R100, including no response from the website.

[Julian Parsons]

First part of large collection of airship specialist stuff is selling 21 March in Lewes, includes a lot of R100 items and photos, though haven't seen anything re AC... see wallisandwallis.org