Most thrust overall?
Well the most powerful aviation gas turbine to date is the GE90-115B, producing a whopping 115,000 lbs of thrust per engine at maximum static thrust settings.
Overall the aircraft with the greatest thrust to date has been the StratoLaunch. With 6 PW5406 engines, each rated at 56,000 lbs of thrust, this gives it the highest takeoff thrust at slightly over 340,000 lbs. For production aircraft, it’s the A380. With 4 84,000 lb thrust class Trent 900s, it gave the jet a massive 336,000 lbs of thrust on takeoff. This beats out even the AN-225 Myria, with its 6 Progress 6DT engines rated at 51,600 lbs each.
The most powerful turboprop still goes to the old dog - The Tu95 Bear. With four Kuznetsov NK-12 turboprop engines, each rated at 15,000 shp, no other turbopropeller came close.
The honor for the highest powered piston driven aircraft goes to the Hughes H-4 Hercules. The ‘Spruce Goose’ was driven by 8 Pratt & Whitney R-4350 Wasp Major engines at 3000 bhp, giving it 24,000 bhp at full throttle. This is also a sobering demonstration of the huge power to weight advantage of gas turbines over reciprocating engines. Consider that the Tu-95 mentioned above has half the number of engines yet still packs 2.5x the power of the Spruce Goose at full throttle.
The gas turbine powered airplane with highest thrust to weight ratio that I ever heard of was a stripped down Su-27 used by the Soviets in the 1980s for setting time to climb records, similar to the F-15 Streak Eagle program. The plane had a thrust to weight ratio of nearly 2:1 and had to be held back by steel cables during run up to full power as its own brakes were insufficient to restrain it.
But the X-15 beat them all. With a gross weight of 27,000 lbs and a Reaction Motors XLR99 Rocket Engine to give it a push at 70,000 lbs of thrust, it claimed a thrust to weight ratio of nearly 2.6:1!
Who knows? Maybe there’s an Aurora driver at Area 51 reading this right now who’s getting quite a chuckle out of it as he knows something I don’t!