Hi. Had a look around the forum, but didn't find a good answer for my question. did find a few things to check though.

 

This specifically references turbroprop engines.

I have a B1900D that I fly. It's static thrust rating in the aircraft .cfg file is 150.

 

If I go look up B1900D technical specs, I see a PT6 engine with 1279 shp (Shaft Horsepower) rated at 954kW takeoff thrust. Have looked for a good technical spec conversion for Shp or kW to lbs/ thrust but have not found a good one. Can anybody converrt the real PT6 engine specs into a real value for the static thrust rating in the .cfg file?

 

In comparing aircraft the static thrust rating of the default Beech King Air is 158.

The BAE ATP is 2200 which is what I'm thinking the B1900D should be close to.

 

I can only get 220 knots out of my 1900D at most. The real specs say I should get over 300.

So, I'm guessing something is goofy with the static thrust number.

 

Appreciate any input you have.

 

Bill

Hi.

 

Strictly, there is no conversion.

 

Thrust is a force (lb / sq in in Imperial, or Nm^-2 in SI units).

 

Power (horsepower in Imperial and watts in SI) (W = Nms^-1) is proportional to force (Nm^-2)× speed (ms^-1).

 

Since static thrust is measured at zero speed, the power developed is zero. Always.

 

Sounds counter-intuitive doesn't it.

 

I suspect the static thrust rating in the cfg file is a Microsoft fudge factor. The best way to establish some sort of conversion factor is probably to have a look at a good sample of other config files and compare values for static thrust rating, power, max speed et c.

 

The choice of IAS, CAS, TAS or GS may influence things too.

 

Best regards,

D

Doh!

 

Sorry... thrust is a force but I've been using pressure in the post above and it's too late to edit.

 

Power equals pressure times speed, and power is proportional to force times speed. Whether it's pressure or force the outcome is the same with zero speed.

 

I'd only had one coffee.

D