Spitfire makes only 300 mph?

[Peril]

Originally Posted by Kurfürst

Looks like it's only a faulty boost gauge Than..



The thing about rpm is odd though. I believe you have to fly 3000/+12 to get max speed, less rpm should yield less power..

Not less power 'to the air' if your prop is entering compression FX due to high tip speeds. Power to the engine is one thing, transferring this to the prop/air another. The larger props in Targetware also had the same effect where props became inefficient in this manner at high RPMs..

Perhaps the props data/size is wrong if this is incorrect here?

Food for thought.

[Viper2000]

Originally Posted by Peril

Not less power 'to the air' if your prop is entering compression FX due to high tip speeds. Power to the engine is one thing, transferring this to the prop/air another. The larger props in Targetware also had the same effect where props became inefficient in this manner at high RPMs..

Perhaps the props data/size is wrong if this is incorrect here?

Food for thought.

Typical tip Mach numbers were around 0.9ish (column #6); typical prop efficiencies were around 70-80% (column #12/13), and shock losses were assumed to be about 7% (column #14).