After all these years WOFF’ing I thought I had seen it all but apparently not.
Flying a Balloon Defense mission (luckily) in my Dr.1 when I get a “System Failure” message. Normally the cause is pretty obvious but not this time. Check the Triplanes sparse gauge set-up and, seeing nothing, keep flying. Speaking of that what is the gauge on top of the cowling? I forget.
Anyway after about 5-7 minutes I start to hear a rather high pitched squeal and since I was behind the lines immediately switched off the engine thinking the next thing will be a fire. Was this a simulated failure of the lubrication system?