SPIT MK I/II and over boost

[41Sqn_Banks]

Originally Posted by Crumpp

There is a definite fixed by design relationship between airspeed and climb rate based on excess power or thrust depending on whether we are talking rate or angle of climb.

Again ... you are talking about TAS and I asbolutly agree about the relation between TAS and climb rate. However IAS is influenced by installation and instrument errors and density of air. The "design relationship" cannot take these factors into account, hence there is no direct relation between IAS and rate of climb.

TAS and climb rate are in relation.
TAS and IAS are in relation.
But there is no direct relation between IAS and climb rate. For example: IAS changed becaused by a frozen pitot tube, but this will not change the climb rate.

I want to make clear that I do not want to say that IAS is mathematically constant for a theoretical maximum rate of climb. I absoluty agree with you that theory says is is decreasing. However what I want to say is that there are pratical references that indicate that for a specific aircraft the IAS for maximum rate of climb can be near constant over a certain altitude range.