Jim Bailey, Yellow Springs, Ohio wrote and published a sim for CP/M back in 1987 called "Instrument Flight".
He describes it:
"It had four aircraft, realistic flight characteristics, character graphics of the standard T instrument panel and also included a view of the runway after breakout. Very crude. There was also an interpreter which you could create your own scripts for to provide ATC guidance. Not a canned script, but rather the ability to request vectors on the fly and get an intercept to the localizer or request the full approach on your own. It hollered at you if you were off your altitude!
It was marketed by Spite Software in Portland, Oregon for USD$40. It was featured at the front of their Spring 1988 catalog. There was also a nice review of it in CP/M Times for Spring 1988.
I had a lot of fun writing it and made a little money too. I ended up getting an instrument rating eventually and own a Cessna 172F which I fly on instruments.
I later wrote another version of the scripting system which used the Heathkit voice phoneme synth and ran in parallel with the MicroSoft sim. It monitored FlightSim's memory to find the aircraft location, heading, altitude, radio settings, etc. You pushed key sequences to make requests or respond to queries and ATC talked back in that funny voice we now associate with the weather radio.
It worked great but I couldn't sell it because the new SoundBlaster D/A boards came in and wiped me out. Played with the damn thing for many happy hours though. Both projects were pure fun!
Thanks for the museum. Very interesting."
Jim Bailey, Yellow Springs, Ohio
It hollered at you if you were off your altitude!