Engine/Prop

Question 1

Would it be normal to run the engines with manifold pressure higher or lower than the propeller RPM?

Answer 1

Run the engine with the MP lower than the RPM

To avoid stress and detonation on the engine, the MP should not be higher than RPM x100

Increase power- Prop up before throttle (Rev up)
Decrease power- Throttle back before Prop (Throttle back)

Question 2

In the event of a propeller overspeed, what would be the best course of action?

Answer 2

Throttle to idle , prop RPM to midrange , if this doesn’t work reduce airspeed, rpm, shutdown engine and feather

Question 3

With regard to best range what would be the best settings for RPM (min/max) MP (min/max) and Mixture (rich/lean)

Answer 3

RPM - mid range
min RPM for min MP
Lean mixture - consult POH for best power settings

Question 4

What is the purpose of a propeller CSU?

Answer 4

To match propeller RPM as selected to changes in airspeed - to maintain selected RPM - it controls the flow of oil into the propeller hub.

Question 5

How is the temperature of the engine oil controlled?

Answer 5

It is controlled via an oil cooler. Comprises of matrix of baffles or galleries which oil passes through- matrix absorbs heat and exhausts it overboard.

Anti surge valve fitted allows cold viscous oil to bypass or in event cooler is blocked.

Question 6

During engine run up, at what RPM are the magnetos tested?

Answer 6

2200RPM ( 175rpm max drop and within 50rpm drop of each other) - it puts a load on the system