CYAC.COM is a crack for the Chuck Yeager's Air Combat.
======================================================
NOTE: I know there's a yeager.com out there, but someone mentioned that it
didn't work for them, so I uploaded this file.
======================================================
It will execute the file yeager.exe (hopefully) disabling the doc check.
The loader needs about 1K of RAM for itself + some RAM for a copy of the shell
(COMMAND.COM in my case takes 2.8K) + whatever is needed for the yeager.exe.
I'm sorry, but it has to load shell, so make sure your COMSPEC is set.
Overall you can run it if you have 4K of RAM more than the game needed.
I posted the patch for the yeager.exe some time ago, but people have trouble
finding an expander for the executable (it's OPTLINKed) so here is the loader.

usage: CYAC parameters
File yeager.exe should be in the working directory or in the PATH.
E-mail me in case of problems.
                                                       Michael Yakubovich

Internet:       U94_MYAKUBOV@VAXA.STEVENS-TECH.EDU
Bitnet  :       U94_MYAKUBOV@SITVXA