Tinstaffl, I didn’t say the climb rate is unchanged. In my scenario, which is academic, the excess thrust is unchanged, which implies the climb gradient is unchanged, which implies the ROC is increased for a temp increase. And actually, I wasn’t using any graph, just a 3 step hypothesis that I thought is clear to follow, but difficult to explain. See my previous post.
Oh, I see bookworm posted a reply so yours also.
Here's the 3 steps again
1. Regardless of temperature, climbing at V min drag gives a constant amount of excess thrust.
2. This constant amount of excess thrust gives a constant climb angle.
3. This constant climb angle gives a higher rate of climb on cool days than very cold days.
Caveat: dealing with a case of near CONSTANT thrust output from the engine, eg non bypass jets.
(See Keith's earlier posts about why this is not entirely possible).I use "cool" and "very cold"
to avoid the flat rated questions.
Bookworm, your question about Keith's post was
"Surely the drag depends on the dynamic pressure and therefore the CAS squared?"
Not sure what you mean. I get dynamic pressure is .5 * V ^ 2 * p
and therefor to tas squared. Drag = thrust required, and P = T x V, so Power is proportional to tas cubed.
this help?