Mark Warren performed a calculation that scaling up the F35-B’s thrust ratio (55,000 shp delivering 41,900 lb thrust) implies the Helicarrier carries engine(s) capable of 157 million horsepower (shp) or ~117 gigawatts output. Allocating 20% of the carrier’s gross tonnage to the power plant sets the minimum power density at 10.8 kW/kg.
A 650 MW thermal integrated molten salt reactor with a supercritical CO2 turbine would have about 400 MWe of power with about 200 tons of weight. This would be about 2 kW/kg.
There have been other molten salt designs with about 18 KW of power per liter. Those are early generation designs and the engineers believe that they can achieve 100 kW per liter. So yes an advanced molten salt reactor could provide the power for a SHIELD helicarrier.
This is interesting but also shows that advanced molten salt reactors and supercritical CO2 turbines would be so revolutionary in their power density that even fanciful engineering becomes feasible.
The Nimitz class aircraft carriers were built using HSLA-100 steel. They are 333 meter long carriers displace about 100,000 long tons. S.H.I.E.L.D, with flight as a design goal, would clearly upgrade to titanium, employ aircraft construction techniques, and use other advanced methods to lighten their 450 meter Helicarrier by about half to 55,000 metric tons (MT).
The Rolls-Royce LiftSystem® enables short take off and vertical landing (STOVL) operations for the supersonic capable F35 Joint Strike Fighter. The LiftFan, a 50-inch, two-stage counter-rotating fan capable of generating more than 20,000lbf of thrust, is driven from a conventional gas turbine and produces the forward vertical lift. The 3BSM is a swivelling jet pipe capable of redirecting the main engine thrust downward to provide the rear vertical lift. It can rotate through 95 degrees in 2.5 seconds and passes 18,000lbf of thrust. Aircraft roll control is achieved using the Roll Posts mounted in the wings of the aircraft, which provide a further 1,950lbf of thrust each.