A Google search threw up a few references in an archive held at the Archives Centre, Churchill College, Cambridge. I combined a visit there with an appointment at the Union.
In a set of papers in the archive left by Air Commodore Francis Banks, who worked on combustion engines all his life, I found a few references. This is a summary of my findings so far.
The testing of the engines would go on until late into the night on a regular basis. It was, of course noisy and many things were deployed to counter-act the effects of such prolonged noise and smog.
A document on the Evolution of Schneider Engines by FR Banks goes into details about his experiences.
At certain power levels of the engine, the sound is so intense, and the walls so bare it was able to bounce the sounds off and intensify them even greater, that the body would literally shake. He recalls that as well as the bone shaking, the assault on his eardrums was so massive, that after just 30 minutes, he would be effectively deafened for 24 hours, and still hear buzzing in his head after 2 days!
Of course nowadays, one would not dream of using cotton wool as ear protection. Apparently back then, it seemed normal. FR Banks noted that such protection was useless, and full ear defenders were absolutely necessary. He doesn't note if the effects noted above persisted after use of the defenders. If so, I'd hate to think what effects not wearing the tins would have had.
To get Air Ministry funding for the development of the engine, Rolls Royce had to prove they could get an engine to run for an hour at full throttle, above a certain RPM, and a certain Bhp. These figures varied on what class of engine, and the intentions sought in development. I later learned that Rolls were a reluctant, late entrant into the game, but more on that later.
Many a time, eager, hopeful eyes were checking their watches as timings for tests approached 50 minutes. One one occasion, after a running time of 58 minutes, the assembled crew got showered by hot aluminium rivets as the carburettor split open. Crank shaft failure was blamed, and things weren't looking good, until it was found that the particular shaft had already totted up nearly 5 hours of running.
As well as the ear defenders, the crew would drink lots of mugs of milk. This had the effect of counteracting the exhaust fumes and poisonous gases. No clues are given if this was mixed with anything else, like coffee.
The engine has to start at between 1000 and 1500 rpm, until it warms up, it then has to boost its speed, and then manage to run unhindered for an hour. As I said earlier, the ranges depended upon the eventual class and development of the engine. To pass it's tests, the "R" had to run at 3200rpm and give 2000bhp.
In the end, the engines managed to do 2350 bhp,and weighed in at 1630 lbs which worked out at 11oz per bhp, or 200 bhp per cylinder.
You can tell these days are before the Arab world went into revolt over the perceived cheap price of gasoline. The "R" burned 3 gallons per minute, resulting in 200 gallons per test. It's written that they needed 80 gallons just to get any circulation in the petrol system at all.
FR Banks concludes with a few choice words about the predominantly young test crew at Roll Royce, and their work...
The cost of the "R" is very high, but the knowledge gained can be used immediately for the betterment of standard aero engines. Potentially this puts Rolls Royce and this country 5 years ahead of everyone else, and so it's cheap at the price.!
A finer crowd to work with would be difficult to find.
I have only scratched the surface on what the Archives held, I feel.
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