Inaccurate performance data for BOB fighters in COD comparing to RL data

[Skoshi Tiger]

Originally Posted by Crumpp

Sometimes it will and sometimes it will not.....

It all depends and it is just as likely to end your trip that flight as the next if the motor is damaged.

I doubt it would be just as likely. If you read the memorandum point one and two,

"A recent increase in the number of engine failures, due to the failure of bearings, is an inication that some pilots are over-stepping the engine limitations laid down in the Pilot's handbook.

2. The use of the automatic boot cut out control enables the pilot to get an emergency boost of +12lbs per sq in. from the engine for 5 minutes when circumstances demand it. Some Pilots "pull the plug" with little excuse on every occasion."

The wording of this memo suggest that the practice of exceeding the limits was quite widespread. Now if it was as you suggest a 50-50 chance of engine failure when the limits were exceeded then the culprits responsible for abusing their engines would be quickly identified and I expect grounded. The practice of exceeding the limits would only become common place if the pilots thought they could get away with it. Maybe thats why they put the wire seal on the boost control to make it obvious to the maintenance staff that it had been used. Then the pilot would have had to justify their use of boost after the mission.

As long as they didn't overheat their engines and the correct fuel was used the boost control still limits the boost available to stop destructive pre-ignition and detonation as a cause of engine damage. (ie if you run the 12lb boost on 87 octane fuel you could get servere and possibly imediate damage from detonation, but not with 100 octane fuel.) So what was left was damage caused by accellerated wear on the engine that was "liable to manifest themselves on some subsequent occasion"


http://www.spitfireperformance.com/dowding.pdf