I am hot, high, heavy and surrounded by mountains.
Accordingly, I have tried to find any reference in the PA31-350 POH to Max Continuous Power, or full power time limitation and can find neither, which rather surprises me.
Does anyone know a reason for not operating TIO540s at full power from 5600’ to 12000’?
Isn’t temperature the limiting factor – ie if in temp limits you can continue? The Lycoming engine manual as opposed to POH may be more useful?
If there is not a limitation in the AFM then it isn’t a limitation.
JasonC wrote:
If there is not a limitation in the AFM then it isn’t a limitation.
Is the right answer. Just watch temperatures. Some engines state MCP as a limitation, others do not. Also, reading the Lycoming manual for the engine may prove informative.
If there is not a limitation in the AFM then it isn’t a limitation.
…on the other hand, we know so much more now than we did when the POH was written.
It is sobering to think that the time from then to now isn’t much less than the time from the Wright brothers to then!
That’s why I was wondering whether anyone knew a reason, rather than what the POH says (which is mute.)
Actually, the PA31 is one of the few aircraft of that era that has LoP in the POH, so maybe the team were a little more switched on than their contemporaries.
Anyway, I’ll probably be off before most of you have woken up on a Sunday morning, so I’ll just suck it and see.
LOP was known by Charles Lindbergh. Quite an interesting history there. The problem with LOP is that, without engine instrumentation, the pilot needs to be way smarter than average.
Most Lyco engines are rated to run at max power continuously, subject to the CHT/TIT limits. The main change there in recent decades is the view that Lyco’s 500F CHT limit is too high unless you are renting the plane 
How did it go?
What do most people treat as max CHT?
I configured my EFIS to go yellow at 400. Occasionally see it, but usually that’s a trigger for a bit more IAS.
On our C210 (the only airplane I fly with an engine monitor) I try to keep them around 360F. The Alarm is set to 400F.
