When I got into my A7 squadron, they were still flying the A-7B Cosair which had a TF-30 engine in it, and was considered on the low side for performance in the A-7.
That was the same engine that was used in the Tomcat, and was basically not a fighter engine, but a bomber engine, so it didn't perform the same way (responsiveness-wise) that they would expect a fighter engine to respond. I believe the same engine was used in the F-111 (engines were designed for the F-111) and was subject to the same issues.
The F-14D had the GE F110 engine which was apparently pretty good, and made the plane truly awesome.
When we upgraded our A-7B Corsairs to A-7E Corsairs, it used a Rolls Royce-Detroit Diesel Allison TF-41 engine which gave improved performance, but had issues with turbine blade cracks. It was a higher bypass turbofan engine, and because of the turbine crack issue, the engine used a thermocouple-limit mechanism (a governor on the temperature at the outlet of the turbines (EGT) so if the temperature got too hot it would cause the engine to lose power and reduce the temperature or keep it steady. That helped with minimizing the turbine cracks.
As an aside, the TF-41 engine was also used in the Royal Navy F-4 Phantoms which they flew into the 1990's.
Every x amount of flying hours (maybe 500, I don't remember exactly) we had to remove a fuel nozzle and feed an optical borescope into the combustion can, feed it back to the turbine, and examine the turbine blades individually for cracks. One person would operated the borescope and examine the blades, and at their command, someone else would give a turn to the turbine with a giant ratchet wrench attached to the gearbox so more blades could be examined.
We had a guy who fed the borescope in a little too far, and when he told the guy to advance the blades, it simply chopped off the end of the optical borescope. Someone once told me those borescopes cost something like $50K-75K in 1970's money!
My last job before I got out was to work with Detroit Diesel Allison to install an Inflight Engine Condition Monitoring System (IECMS) which was a new thing for combat planes at that time. We were a pioneering squadron. Detroit Diesel Allison specially installed all kinds of sensors on the engine, and figured out how to write them to a recording tape (a metal cube about 3 inches to a side) so they could try to predict in advance when a plane might be developing problems that could result in a loss of an engine. They recorded exhaust gas temps (EGT) vibration, airspeed, RPM, throttle position, altitude, and so on.
When every flight came back and landed on the ship, I had to be there to pull out the big heavy recording tapes, put a fresh one in, and record and manually reset any alarm flags on a analog visual indicator.
The parachute riggers made me a special bandolier for the flight deck that I could carry six of the tape cartridges in.
I then took the tapes down to a special compartment, hooked them up to a Digital PDP-11 computer, download them and make a special paper tape record of the flight (it was so primitive by today's standards, it was a roll of tape maybe an inch wide, and as you transferred it to the tape it made a pattern of holes in the paper roll of tape that could be played back!
I had a special program where, if I saw any issues, I could choose the appropriate parameters in the program that would best display the issue, set the axis correct to best display them on a paper graph, print it out and give it to the maintenance officer and the Detroit Diesel Allison representative.
For example, if a vibration flag was triggered in the plane, I would read the tape, select the RPM, EGT Vibration level from the appropriate sensor and throttle position, then plot and print them.
It was very heady stuff then. Of course, all of this is completely standard on all military aircraft now I presume, but in the late 1970's...it was pretty cool.
Here is a link to a technical article, and shows a depiction of my squadron's plane at the time (1978): A-7E/TF41 Engine Conditioning Monitoring System
Funny...as I used a command line interface to enter the parameters, you would occasionally mistype something, and it would spit back "PARAMETER INCORRECT-REENTER PARAMETER"
One day, I kept reentering the wrong thing and after the fourth or fifth time, the program spit back "PARAMETER INCORRECT-ARE YOU IN THE US MARINES?"
When I got it wrong again, it said "PARAMETER INCORRECT-WHAT IS ON THE END OF YOUR ARMS SHITFINGERS?
As I continued to deliberately make mistakes, it spit back ever increasing obscene and abusive responses to my mistakes! I thought it was hilarious!
Someone, somewhere had a sense of humor!
I was on the Big E 73/74.
Welders cut through a bulkhead into the tape storage room.
Firefighters then ran into the computer room and sprayed down everythin with salt water.
ROFL!!!
I didn't write that program … but I have written software like that.