Pretty much all flying was suspended today due to poor weather and no combats were reported – no doubt a welcome day off for the pilots of the RFC who have been suffering from high losses.
Castor oil is used as a lubricating agent in rotary engines by injecting it directly into the fuel/air mixture. The design of the rotary engine without an oil sump means that all the lubricating oil is lost during flight (a “total-loss” system). Again having no sump, the oil is simply thrown out of the engine into the air – a rate of two gallons (4.5 litres) per hour is typical. Most rotary engines had a cowling to direct the oil away from the pilot, but this does not appear to have been completely successful as many pilots talk of being covered in castor oil after a flight, and many aircraft have tell-tale stains on the fuselage from the oil.
Castor oil is a well-known laxative and some pilots have also commented that one of the unfortunate side effects of being splattered in oil is nausea and diarrhea. Many are known to drink brandy and milk in an attempt to stave this off. Though others suggest that this is an old wives tale and may simply be a cause of the natural fear of flying in these contraptions with the enemy shooting at you. The alcohol again may just be a way of calming the nerves.
Perhaps the German the the German use of “ersatz” mineral oils becasue they cannot get castor oil has some advantages afer all.