The A-10 is a much loved (Army/Marines) / hated (Air Force) combat aircraft. I'm a big fan.
An interesting fact:
When I first started at Lockheed Skunk Works in 1985, I took a class in 'Survivability.' After all, Lockheed was still building the F-17 and supporting the SR-71. They should know something about survivability and 'STEALTH.'
The A-10 entered service in 1976. The A-10 was a first generation STEATH aircraft.
Wait?!?!?!? How can a aircraft as ugly and as obviously non-stealthy as the A-10 be considered a first gen stealth airplane?
STEALTH is a function of threat environment. For most aircraft (high flyers) the primary threat is RADAR. Hence, the development of "RADAR" stealth, if you will.
The A-10 is quite capable of 'taking a beating and still ticking,' as long as it is from small arms fire, etc. The cockpit is fully covered with heavy armor, critical systems are protected, too. But what about the engines?
The primary A-10 threat is infrared guided missiles. The most common, with respect to the A-10 that are threats, are called MANPADS. See the link.
https://en.wikipedia.org/wiki/Man-portable_air-defense_system
The A-10 engine placement is what makes the A-10 'STEALTHY.' The exhaust of the engine is very hot and also parts of the engine are very hot. The front compressor is also a heat source, but in a different IR frequency band.
If you look, the engine front face is hidden from ground view by the wing. The even more critical engine exhaust area is hidden by the tail plane and verticals of the A-10.
This is how the A-10 defeats MANPADS, its primary threat.