Hi GtE, I wonder how you factor in height asl in those calculations ?
Our flying club had recently fitted a new propeller to a C152, so myself and my passenger took it out to see if we could find any performance increase. We climbed to about 10,000ft where we found it just ran out of lift.. 50ft/min was all it would do. Pull back on the stick and it would descend (-300 f/m.).. Push forward and it would descend, any angle of bank and it would descend..
Whether this could be called a stall I don't know, but there was only one stick position that would give us a climb.... The engine was leaned out for max rpm, which I think was about 2300 rpm. The Indicated airspeed was about 60 knots. At a rough guess we would have run out of fuel before it would climb another 1000ft.
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