[camber]

Hi Gentlemen

Originally Posted by IvanK

I guess the lead was maxed out as well. The convention is the lead would in normal circumstances give the wingman a "bit to play with" by setting a slightly reduced power setting. In a combat tail chase I guess the formation protocols were overlooked.

That is a more logical explanation. Perhaps that part of the report is a subtle dig at blue leader

Originally Posted by 41Sqn_Banks

My interpretation is that it is calibrated to +12 but on some days would rise to +12.5 and on other only to +11. So there is a 0.5 safety mentioned in the manual so the pilot doesn't panic if boost is higher than +12 on one day.

That makes sense

Originally Posted by 41Sqn_Banks

We should have a closer took to the mechanic of the boost control to understand what happens if gate and cut-out are activate at the same time. I'd suspect that the gate has the upper hand.

I am only going from http://www.enginehistory.org/Piston/...erlinABC.shtml, but my model of the function is as follows:

For the sake of argument I will state that at sea level, +12.5 psi boost is given at 60% throttle valve opening (real percentage unknown). The rated boost setpoint is +9psi, +12psi emergency with red tab pulled.

The pilot takes off with pilot throttle through the gate. The boost controller piston senses that boost is too high (>9psi) and is against "boost too high" rearward stop. But the gated throttle extension pulls the throttle valve to 60% open giving +12.5 psi.

As plane climbs initially, boost remains >9psi so the boost controller piston remains stuck on the "boost too high" stop. If the pilot throttle is kept gated, the resulting 60% throttle valve opening corresponds to less and less boost with height, and finally boost decreases until it is under +9psi.

At that point the boost controller piston has a job to do. It moves away from the "boost too high" stop, opens the throttle valve further (i.e. > 60%) and then keeps increasing it with height to maintain +9psi boost. At 100% throttle valve opening it has reached FTH for +9psi, the boost controller piston is at the "boost too low" stop and boost starts decreasing with more altitude.

At a "combat" height where the boost controller already has throttle valve opening >60% while maintaining +9psi (i.e above the effective take off boost height), what would happen if a pilot seeking more power suddenly goes through the gate?

Effectively nothing, as boost would remain at +9psi. But actually, boost would momentarily rise (how much depending on mechanical dynamic constraints on the control system). The boost rise would be momentary because the boost controller piston would react by moving closer to the "boost too high" stop in order to override the gate input and return the boost to +9psi. The only difference afterwards is that inside the boost controller, the piston is at a different position than before.

If the red tab is pulled, the same applies but the +9psi is instead +12psi.

So my take is generally the boost controller wins, not the gate. The documentation states the take off boost is ineffective over low altitude, but does not warn of adverse consequences if it is used higher. So I still think it is just ineffective and going through the gate is fine in combat (but make sure you pull the red tab, that IS important!).

Cheers, camber