.To expand on an above comment. It is possible to have HORSEPOWER without TORQUE. Torque relates to ROTATIONAL FORCE . Horsepower is the rate of doing work, Move a weight through a distance in a certain period of time and you can express it as HORSEPOWER,or WATTS or various other quantifications. The work could be a hydraulic cylinder lifting a weight or a dog pulling a sled.
For work to be done there must of course be movement through a distance. A steam engine exerting a force but not rotating ( ZERO RPM) is producing ZERO HORSEPOWER
In many aircraft applications the HORSEPOWER figures are very misleading. Very often a screaming 2 stroke making 3 Horses at the crank will not pull vertical as well as a 4 stroke making only 1.5 horses at the crank.
The difference is EFFICIENCY , smaller props at high RPM are not as efficient as larger ,slower turning props. This is where REAL horsepower measurement would calculate how fast a 10 pound plane climbs vertically with a two stroke and compare that rate of vertical ascent two the 4 strokes performance with the same plane at the same weight.
Not saying horsepower is meaningless ,just that the HP number doesn't always mean performance.