Instrument readings for Mil power?

[Voyager]

Is there a general guideline on what the engine instruments should read for Mil power? Trying to get the power settings for takeoff right, and not sure what I should be seeing on the gauges to show its set right. Piston Engines typically have a manifold pressure and RPM you're supposed to be at, but I'm not sure what the equivalent numbers would be for the F-14B's GE's

 

Thank you,

 

Harry Voyager

Edited April 30, 2019 by Voyager

[electricaltill]

Is there a general guideline on what the engine instruments should read for Mil power? Trying to get the power settings for takeoff right, and not sure what I should be seeing on the gauges to show its set right. Piston Engines typically have a manifold pressure and RPM you're supposed to be at, but I'm not sure what the equivalent numbers would be for the F-14B's GE's

 

Thank you,

 

Harry Voyager

Be wary of the gauges. The fuel flow gauge in particular is for the (F-14A) TF30 engines, for unknown reasons. Heatblur acknowledge this in the manual and state it will be changed eventually.

 

Fuel flow at military power should be about 10,000pph, (per engine) and as you'll see the gauge shows completely different.

[Voyager]

Ok, so I understand, if the instruments were working correctly, should I be controlling jet engines by fuel flow? Or is it a different control factor? Or are jet engines inherently "squishy" at the instruments and should only be managed by throttle position?

 

Understand, In coming in form props, where there is a strong link between manifold pressure and power output. Does such a relationship between fuel fow and power exist here?

[sLYFa]

where there is a strong link between manifold pressure and power output. Does such a relationship between fuel fow and power exist here?

For jets with large bypass ratios, N1 is used to measure power output. Some engines show EPR (engine pressure ration) which is even better. None of these are available in the F-14 though, so you are stuck with N2 (for the Tomcat probably even better then N1) and FF to judge power output.

I prefer to use FF as it can be read more precisely on the tape gauges, will vary strongly with altitute however.

For MIL power, you should get the following readouts depending on ambient conditions:

RPM: 95-104%

EGT: approx. 935

FF: 9000-12000 PPH

[Longiron]

Can also reference nozzle position for full military power, it will be fully closed.

Also good to use if you want to throttle the AB, just watch nozzle position but AB is pretty sensitive.

[Eldur]

Fuel flow at military power should be about 10,000pph, (per engine) and as you'll see the gauge shows completely different.

 

Well, that's exactly what I get, so it's definately not completely different. The numbers are obstructed, but counting the dashes up, it shows the tapes just at or slightly above the 10 mark. To the left, the nozzle indicators (those that go up to 5) are down to 0. Before reaching mil power, the nozzles are open slightly, indicating something 0.1-0.2ish. Then they pop down to 0 when pushing the throttles forward. That and a clicking noise are the indicators that you're at mil. Pushing the throttles further forward will eventually engange afterburners and the nozzles will open up to 2 instantly from where it is possible to reduce the afterburner power until it's shut off again once the nozzles are completely closed again. And again, afterburner FF is not shown, neither in the A, nor in the B AFAIK.

 

The thing that has to be changed still is the TIT gauge which is for the TF30. The F110s should have EGT tapes instead and probably different numbers as well.

 

Edited May 1, 2019 by Eldur

[Voyager]

Ok, so to recap, at takeoff, run the throttle up until the fuel flow hints 10kpph (one notch below the top of the upper white male on the FF indicator) then let the engine spin up to 100% RPM, and watch the nozzles to make sure they don't go over 1.5-2?

[electricaltill]

Well, that's exactly what I get, so it's definately not completely different.

I was speaking in terms of the fuel flow in relation to the throttle position, in which sense MIL is not military power...but I'll leave it there so I'm not repeating myself from my other thread.