I thought some of you might get a laugh out of this:
So I just unlocked the S.U.R.G.E in my career game, and deciding to be prudent, tested it out in my sandbox. I'm glad I did, because I now have to mount a rescue mission for an AIRCRAFT that is stuck in ORBIT. I was really surprised at just how much thrust it got in the upper atmosphere. I did NOT expect it to shoot the thing all the way to Iota's orbit (GPP). I especially didn't expect it to get an encounter with it, let alone get a small gravity boost that put it into orbit! So here I am, looking at an aircraft with an atmosphere-only engine, in a stable, if very eccentric, orbit, holding two Kerbals, no supplies, and the only thing in the way of habitation (MKS-LS) is the cockpit. Time to start planning the rescue craft...
A beauty shot and screenshot of the orbit: