Sign in to follow this  
Damlimey

Chicken & Egg

Recommended Posts

Hi all,

Another sound.cfg related question.

During an engine start up, does the start up sound drive the timing of the engine start up or is the engine start up driving the sound?

The reason I ask is that I want to slow the engine wind up down a little in one of my models rather than having it all just burst into life.

If it is the engine that drives the sound, is there a way of affecting the timing?

Thanks in advance,

D

Share this post


Link to post
Share on other sites
Help AVSIM continue to serve you!
Please donate today!

Although I suspect that the engine start up drives the sound, I have to admit that I don’t know the answer to your very good question! I have lots of addon aircraft and, in many of them, the sound does not seem to be well synchronised to engine start / propellor animations. This applies particularly to some of the old large radial engines where, during the startup process, the prop generally had to turn through 10 or more blades before ignition was initiated. In the main this is poorly replicated except by one or two developers and in many the engine simply bursts into life, as you describe.

Bill

Share this post


Link to post
Share on other sites

Yes, it does seem to be something that has no obvious control mechanism beyond getting the bonnet up and digging into FS. However, like you I have seen some models where the start up seems a little slower. I'll be interested to see what some of the grown ups in here know about it.

D

Share this post


Link to post
Share on other sites

The way we retard the turbine startup involves using custom sound files and coded timing of the playback in addition to an external engine simulation that doesn't use the sim's turbine data .

Default turbine modelling will only spool up quickly , nothing you can do in the sound folder to change that .

Best CJ

 

Share this post


Link to post
Share on other sites

Another way of stopping a jet engine from springing to life like a recip in FS9/FSX is to monitor the combustion flag using FSUIPC in a gauge or LUA script, and quickly cycle it from on to off to on as soon as the engine lights off (e.g. as soon as combustion flag changes from 0 to 1 during start)...this interrupts the start sequence coded in the sim and the engine will then spool more or less normally.  If you do it that way, custom sound files aren't needed.

Regards

Share this post


Link to post
Share on other sites

What w6kd has said is very interesting as what I have done so far is to substitute the fuel pump sfx for a turboshaft wind up sfx which runs until the fuel valve is opened and the start up is triggered. All of this sequence is managed by a collective button box of my own design using FSUIPC.

So, my question now is... Would the combustion flag manipulation be covered in the FSUIPC users or advanced users guide or do I need someone like you to talk me through it? (Hint, hint).

In excited anticipation,

D

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this