Two problems. First, a downloaded Bloch 174. Engine parameters in .cfg and .air files are correct. But, on attempting take off, the engines give less than 20" MP and less than 1000 RPM - should be 45" and 3000 RPM. At full power, the aircraft won't move - and, yes, the brakes are OFF.
A similar problem with some flying boats. Some will take off quite happily: others just wallow there at full power and don't move.
Any ideas
If you have Propeller and Mixture Controls fitted, make sure that they are both pushed fully forward for take off:
Propeller set fully fine.
Mixture set fully rich.
Trimmed for Take-Off.
Flaps as required.
For float planes, raise nose slightly to put the plane "on the step", (lift the tips out of the water), whilst still in the water...
...patience is required...

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Hope that helps...

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Paul... 8-)...!
...Just a little tip for the unwary...

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If you decide to change aircraft from the aircraft you were previously flying, and you left the Propeller and Mixture controls in the "Coarse" and/or "Cut-Off" position, when you change aircraft they will have very little "power" available, and may not even start..

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Always check the positions of
ALL the aircraft's controls immediately upon changing aircraft...

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Keep your Insurance Company happy, and lower your Premiums!... 8-)...!
...is it just me?...

...None of the Smilies seem to be working!....Bugger!....

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