the recoil force of the A-10’s gun was greater than the forward thrust of the engine.

it's more complex than this - and it's not that the 'thrust of the recoil was greater than the engines' - the problem is gasses produced by the firing process reducing the engine thrust output (and sometimes choking the two giant turbofans entirely!) while simultaneously shaking the entire airframe like crazy and the forces the gun's firing produces against the airframe (long bursts could distort the mounting points). It'll slow the warthog down, but it wouldn't stop it by force of motion in the opposite direction. They also did all kinds of stuff with the barrel shroud and canopy cleaner because fouling would coat the windshield and muzzle blast would blind the pilot

and sometimes not all the propellent in each 30mm shell wouldn't be fully burned before being ingested by the engine, leading to some fun times lol. they figured it all out tho, just do relatively short bursts and an automatic-engine-restarter and it became a really awesome platform.

https://www.twz.com/air/birth-of-brrrrrt-how-the-a-10s-avenger-cannon-went-from-terrible-to-terrifying

edited for derp