High Altitude Landing and Takeoff

[gismo]

Not always. The engine might have an intercooler. Then this logic does not apply.

An intercooler will reduce the induction air temp but not enough to eliminate the heat gained by compression. This along with the airflow lost to the back pressure created by the turbine is the reason TN engines require a slight increase over ambient sea level pressure to make rated power.

 

[Apelsin Elise]

An intercooler will reduce the induction air temp but not enough to eliminate the heat gained by compression. This along with the airflow lost to the back pressure created by the turbine is the reason TN engines require a slight increase over ambient sea level pressure to make rated power.

And this is related to your original statement about DA inside turbo'd intake manifold how?

Effective or not, intercooler changes DA inside intake manifold. Otherwise, what is it needed for?

 

[Henning]

And this is related to your original statement about DA inside turbo'd intake manifold how?

Effective or not, intercooler changes DA inside intake manifold. Otherwise, what is it needed for?

With turbo normalizing, not much since there really isn't a great pressure rise. The primary benefit one sees from an inter cooler is greater resistance to detonation. The only time an inter cooler serves a performance benefit is when the waste gate is fully stopped down and you continue beyond critical altitude.

 

[Apelsin Elise]

With turbo normalizing, not much since there really isn't a great pressure rise.

Then modern turbo normalized systems (TAT, Western Skyways) include intercoolers for no good reason at all?

The primary benefit one sees from an inter cooler is greater resistance to detonation.

Agreed. This is the primary but not the only benefit.

The only time an inter cooler serves a performance benefit is when the waste gate is fully stopped down and you continue beyond critical altitude.

Lower CHTs, lower peak cylinder pressures and lower EGTs are realized way before the waste gate is fully closed.