Question for real life F-15 maintainers

What is the high frequency buzzing noise I've heard Eagles make during some maintenance procedures? The engines are off...

Not an F-15 maintainer, and not sure if this is something you can do without the engines running, but are you talking about the nozzle test?

The sound of something else other than an engine running after engine shutdown.

I'm not an Eagle guy but I think what you are trying to point out is the avionics cooling fans shutting off when the power from the generators shut's off. When engine RPM goes below a certain percentage the generators will stop delivering power to the aircraft systems. Shutting off fuel flow to the engines stops the combustion process but the engine is still spinning keeping the generators running until the engine spool's down enough that the generators will no longer deliver electricity to the aircraft systems to run things like avionics cooling fans.

I'm not an Eagle guy but I think what you are trying to point out is the avionics cooling fans shutting off when the power from the generators shut's off. When engine RPM goes below a certain percentage the generators will stop delivering power to the aircraft systems. Shutting off fuel flow to the engines stops the combustion process but the engine is still spinning keeping the generators running until the engine spool's down enough that the generators will no longer deliver electricity to the aircraft systems to run things like avionics cooling fans.

Well, I want that in my DCS Eagle and any other aircraft with a similar setup...;)

Auxiliary Power Units (APU). Once the engines are shut down, the Auxiliary Power Units disconnect from the electrical busses and that's when the APU winds (whines) down.

Source

Auxiliary Power Units (APU). Once the engines are shut down, the Auxiliary Power Units disconnect from the electrical busses and that's when the APU winds (whines) down.

 

Source

I assume these APU are not like the kind airliners have and you're not meaning the JFS, right?

I think we should wait for someone that has actually work on the F-15.

The F-15 does not have an APU, it has a JFS which is only used for the start and AFAIK, has nothing to do with the shutdown procedures. It could be the sound of the AMADS spooling down but I do not know since my experience on the F-15 is very limited.

Of all the things the FC3 F-15 could use, why bother with something so trivial?

I think we should wait for someone that has actually work on the F-15.

 

The F-15 does not have an APU, it has a JFS which is only used for the start and AFAIK, has nothing to do with the shutdown procedures. It could be the sound of the AMADS spooling down but I do not know since my experience on the F-15 is very limited.

 

 

Of all the things the FC3 F-15 could use, why bother with something so trivial?

What do you want to see?

If you are referring to just after engine shut-down, then the sound you hear is the emergency generator that comes on-line when the generators go off-line. The emergency generator is driven by hydraulic power and there is enough hydraulic pressure to drive it until the engines spool down.

Eagle Keeper for 12 years. McDonnell Douglas and Boeing for 7 years.

Thanks for the info kdrum! :thumbup:

Always great to see so many knowledgeable folks around here.

What do you want to see?

- Completely modeled cockpit with working switches and ability to do all require procedures to run the radar or proper engine start, etc.

- Fully modeled systems.

Thanks for the info kdrum! :thumbup:

Always great to see so many knowledgeable folks around here.

U R Welcome.

- Completely modeled cockpit with working switches and ability to do all require procedures to run the radar or proper engine start, etc.

- Fully modeled systems.

+1

- Completely modeled cockpit with working switches and ability to do all require procedures to run the radar or proper engine start, etc.

- Fully modeled systems.

+1

It almost brings a tear to my eye that nearly all the switches, buttons, connectors, arguments, etc. exist but are linked to nothing.

Even if it's not full fidelity couldn't at least the main comm panel be used for radio

Or the MPCD contrast/brightness toggles

Maybe someday...:cry:

- Completely modeled cockpit with working switches and ability to do all require procedures to run the radar or proper engine start, etc.

- Fully modeled systems.

Yes please :thumbup:

I think we should wait for someone that has actually work on the F-15.

 

The F-15 does not have an APU, it has a JFS which is only used for the start and AFAIK, has nothing to do with the shutdown procedures. It could be the sound of the AMADS spooling down but I do not know since my experience on the F-15 is very limited.

 

 

Of all the things the FC3 F-15 could use, why bother with something so trivial?

I was a F-15 engine guy for 4.5 years

But yes, the F-15 has JFS for starting only, no APU or even battery power. If we needed power, we always used a -60.

I was a F-15 engine guy for 4.5 years

 

But yes, the F-15 has JFS for starting only, no APU or even battery power. If we needed power, we always used a -60.

Do you remember "Limited Duty Mode"? or am I showing my age.

- Completely modeled cockpit with working switches and ability to do all require procedures to run the radar or proper engine start, etc.

- Fully modeled systems.

++1

Do you remember "Limited Duty Mode"? or am I showing my age.

Don’t believe I’ve ever heard of that, lol

++1

+1

A month ago Belsimtek posted this on reddit

If you mean F-15C ASM then we can say that currently it is not on our plate. Currently we are helping ED with F/A-18C. And our current projects are F-4E, Mi-24 and NS-430.. If we will get back to F-15 later we will make community aware of that for sure.

Fingers crossed...