John and David went down to the farm to try out the foam branches. Armed with a few bottles of Aldi’s finest washing up liquid (about 30p a bottle), we got out the Beresford, connected suction to the test tank, put in some petrol and water, and then noticed a lot of condensation on the spark plugs. Hmm, going to be difficult to start. First turn of the handle – nothing. Second turn, cough. Third turn, and it started! The warmth from the engine will soon dry it all out.
So we decided to try the modern (well, 1960’s) foam branch from the Green Goddess, with 25% detergent 75% water in the bucket, being drawn in from the pickup tube. Took a few moments to pick up – possibly air getting in the foam valve. Anyway, after a couple of minutes, we had used most of our mixture, and the foam looked rather good.
The next attempt was using the wartime No 2 Foam Branch, and a mixture of 33% detergent. That got going very quickly and produced very satisfactory demo foam. Two bottles of detergent produced a good load of foam using about 50-60 gallons of water.
Note that this foam differs significantly from the foam used by the Fire Brigades for real. Firstly, it is not thick, firm foam like whipped cream or shaving foam, it is more bubbly. And it does not stick to a vertical wall like real foam – it slides down. But for a re-enactment, this is a positive advantage, making it easier to clear up, and most unlikely to do any damage to any plane fuselage we sprayed, and unlikely to do any environmental damage, as the detergent is bio-degradable.
So this means that we can do a very presentable scenario at an airfield-based 1940s event, such as at East Kirkby, Newark Air Museum, or Elvington. Or even the new air show at Scampton in September? All we need now is a soundtrack of either an airfield being bombed, or an aircraft crash landing, and a bit of flame and lots of smoke. That is for the next training event!