Constant Speed Prop Question

ILSstud

ILSstud

Well-Known Member
As I was flying today I started wondering about the prop angle and RPM setting. If I set a constant speed of say 2300 RPM and 20 inches of MP, and then I reduce the MP to say 15'', the blade angle will increase because of the governor's "input," but what exactly will slow the plane down as a result of the lower power setting (the engine is still rotating at 2300 RPM)? My thought was that the increased blade angle creates a larger drag force coefficient which absorbs energy and bleeds off airspeed. Sorry if this sounded stupid, it's been a while since I've gone over this.
 
If you reduce power, the blade angle is going to have to decrease to a lower ('flatter') pitch to maintain RPM. Therefore, the prop is taking less of a "bite" of the air (AOA is lowered), and producing less thrust.
 
You must log in or register to reply here.
Back
Top