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gothkrieger
07-28-2011, 11:20 PM
How does watching the Engine Manifold Pressure Gauge figure into engine management?

Col_SandersLite
07-29-2011, 03:37 AM
Originally posted by gothkrieger:
How does watching the Engine Manifold Pressure Gauge figure into engine management?

To demonstrate it very simply, try this.

Go to instant action, select a scramble mission with no opponents flying an aircraft with a manual supercharger. Off the top of my head, try an F4u.

Take off and do a standard 100% power sustained climb with rads open.

Watch your manifold pressure as you climb. It will start to drop off. When it does, switch your supercharger to the next stage and you'll see it pick back up.


Unfortunately however, the way manifold pressure is modeled it somewhat simplified and it's generally not all that useful in sim. For example, AFAIK, a lot of these aircraft did not *actually* have waste gates on their throttles. This means that if you apply full throttle below full throttle altitude, you actually get more manifold pressure than the engine is rated for (and you subsequently blow the engine!). This means you have to work the throttle with altitude to keep it at the desired manifold pressure. Try coupling this with a manual variable pitch propeller (IE, no CSP as nearly every aircraft in il-2 has) and you can see just how much workload that would be in a dogfight.