Originally Posted by
India Four Two
I'm confused (not difficult these days!). Does this mean that Cessna de-rated the engine by installing a finer pitch prop? Why would they do that?
And how does changing the prop allow an increased gross weight?
When Cessna restarted the C 172 line in 1996 the engine was changed from the previously used 160 hp carburated O 320 engine to the fuel injected IO 360. This bigger engine is normally rated for 180 hp. However to keep it the same as the old models the prop was pitched so that it would only develop 160 hp. Since the same 2400 lbs gross weight of the legacy airplanes was retained, performance stayed the same.
The problem is the new models fancy interiors and other design changes to make the aircraft safer, added weight. Thus the payload was significantly less than the legacy models. When customers started complaining Cessna decided to restore the engine to 180 hp and up the gross weight to 2550 lbs. The C 172 S now carries the same payload as an old 1980's vintage 160 hp P model C 172, but burns 1.5 gallons per hour more. Isn't progress wonderful
