I did up a sound pack for the C-123 (the original version) that incorporated radial engine and jet engine sounds. It wasn't all that hard to do....I am attaching a copy of the sound config file (renamed as a txt file) so you can look it over.
While we can have mixed-power sound packs, we can't have mixed-power flight dynamics. The best (meaning ONLY) way to do it is to set up the air and config files to use the auxiliary jets as additional radial engines. That's how I set up the original C-123.....as a 3 engine plane. I would start the engines using an engine control panel. First the left radial, then the right radial, then the left jet and then the right jet. Did the same thing for the C-119 with the roof mounted jet pack.
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