S.H.I.E.L.D’s Helicarrier Could Lift-off Using Today’s Technology

S.H.I.E.L.D Helicarrier from The Avengers movie

Immediately after watching The Avengers movie (on opening day; and yes, it’s been quite a while), I set off, tongue firmly in cheek, to reality-check S.H.I.E.L.D’s Helicarrier. Professor Allain’s Wired blog “Could the S.H.I.E.L.D Helicarrier Fly?” arrives at a different conclusion than I did, so I thought it’s finally time to write up my alternate assessment.

Like the professor, I began by looking into Nimitz class aircraft carriers. Built using HSLA-100 steel, those 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 m Helicarrier by about half to 55,000 metric tons (t).

Next, could real fans fit in the space allocated and still generate enough thrust to lift 55 kt? Using the Harriers Alpha Jets on deck as measuring sticks shows that each of the four fans is 51 m in diameter giving a total rotor area of 8,200 m². The Helicarrier name invites comparison with helicopters, so I initially checked its fans against the remarkable Russian Mi-26 heavy-lift helicopter. The Mi-26′ has a maximum takeoff weight of 56 t using a rotor 32 m across to provide a lift/area ratio of 0.07 t/m². That herculean helicopter’s lift/area ratio provides only 1% of what S.H.I.E.L.D needs to fly. Helicopter rotors are out.

Fortunately, engineers have already done better, much better; the Rolls-Royce LiftSystem in the F-35B produces far higher lift/area ratios. For instance, the front LiftFan generates 20,000 lb of lift from a 127 cm (50 in.) fan and the whole system generates 19 t (41,900 lb) of lift from 2.51 m² of duct area (LiftFan, jet exhaust, and roll-posts). Its 7.56 t/m² ratio leaps two orders of magnitude past the Mi-26 and provides plenty of lift-off thrust for S.H.I.E.L.D’s headquarters. To sustain a single rotor failure, the Helicarrier engineers must have improved on Rolls-Royce by at least 14% to 8.61 t/m² or more. Nonetheless, the Helicarrier appears to fly within the laws of physics here.

Spinning those fans requires an enormous amount of power and generating it presents an even bigger engineering problem, but it hovers (barely) within the realm of possibility. 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 (that’s more power than all of the nuclear power plants in the USA combined). Any power source would need to be scaled up, but allocating 20% of the carrier’s gross tonnage to the power plant sets the minimum power density at 10.8 kW/kg; for comparison, here’s a quick rundown of some real-world power densities:

  • A Pratt & Whitney F135 jet turbine in the F35B produces 38 kW/kg
  • The RS-25D Space Shuttle Main Engine delivers the highest power to weight ratio available today at 1445 kW/kg
  • For something closer to home, the LS9 supercharged V8 in a Corvette C6 ZR1 produces 638 HP and weighs 530 lb (dry) for a power to weight ratio of 0.9 kW/kg
  • The Indy Car Series 2012- engine weighs just 112.5 kg (248 lb) and puts out 522 kW (700 HP) 4.46 kW/kg or 5× the specific power of a Corvette but just half of what’s needed
  • A Nimitz A4W nuclear reactor weighs a lot more but at least it contains enough fuel for two decades; it generates 0.05 kW/kg with older, 18% efficienct steam turbines
  • The Los Alamos Heat Pipe reactor (alpha of 0.43) combined with 40%+ efficiency turbines raises its specific power to 0.8 kW/kg

Unlike the Nimitz aircraft carrier, nuclear reactors, even lightweight research reactors, won’t work. S.H.I.E.L.D would need around 530 A4W reactors to generate 117 GW and those would weigh over 2 million metric tons; that wouldn’t just ground the Helicarrier, it would sink it!

Shuttle main engines would weigh 81 t or 0.15% of the total. Using the rest of the weight allocation for cryogenic fuel provides 2 hours of flight time in a tank 111 m long and 11 m in diameter.

Turbines have high enough specific power but need to be scaled up a lot; just ganging together 3,000 P&W F135 turbines would be an engineering and maintenance nightmare! Real-world engines have high enough specific power for the Helicarrier, but scaling them up would be incredibly difficult.

For in-world consistency, I also had to consider Tony Stark’s imaginary arc reactors. His Mark III could generate 3 gigawatts (3×109 watts) and the Mark IV upgrade quadrupled that to 12 gigawatts (12×109 watts). Stark could easily pickup either version by hand and so I’ll assume a maximum weight of 50 kg. That’s 240,000 kW/kg! and a specific power 1,600 times greater than the Shuttle turbopump! Using an exotic power source like that obviates the need for anything fancy; just scale up a standard AC induction motor and watch it fly!

7 Responses to “S.H.I.E.L.D’s Helicarrier Could Lift-off Using Today’s Technology”

  1. Shiloh Says:

    What about the limited use of Hydrogen to help with lift. The gas could be stored in ballast like tanks used in submarines. Couldnt a system like that be used to augment the turbines lift?

  2. MissedThePoint Says:

    That’s gonna be a nightmare for the loadmaster to balance out all that weight for stable flight.

    Would be funny watching lower tech countries using hot air balloon tech to try and match something like this. 😀

  3. RebelDroideka Says:

    Something similar was considered by the U.S. after World War 1, but cancelled because it would have required too much space inside the body of the craft. So the USS Los Angeles (ZR-3) and its sister ships are the closest to a real helicarrier we’re likely to get. http://www.airships.net/us-navy-rigid-airships/uss-los-angeles

    • #iwannarideahelicarrier Says:

      For now.. I could see them working out a project like this, and putting plans in motion to build one within the next, say 15-20 years lol.. every time Hollywood makes a fancy, new looking technology, the military tries to copy it for real world application, and vice-versa.. I would even go as far to say they probably have some scientists locked in a room somewhere right now, working on the theory of it.. once they design it, they need to power it.. therein lies the waiting..

  4. Gerald Nobody Says:

    I appreciate that you took the time to consider changes to the classic aircraft carrier design methodology (i.e. different materials chosen with flight in mind), but I have one more suggestion: what changes in architecture might be allowed that would increase plausibility. We’re not talking in this article about efficiency, of course, just “could it be done?”

    Specifically, a floating aircraft carrier has horizontal runways that emulate land-based runways, and specifically, typically two or more of them. The two reasons I can surmise for this are: (1) catapulting a plane /upwards/ (against gravity) would take a good amount of power and extra machinery compared to the horizontal catapult used today, and the only other way to let them go is horizontally; and (2) the planes need wind to create lift, so the ship turns based on the wind to maximize this effect, both for takeoff (for lift) and landing (breaking).

    In a helicarrier, however, it seems to me that you could effectively drop planes (at an angle) to let them accelerate, and with sufficiently accurate sensing equipment and computer controls, might be able to let them fly up to the carrier (again, at an angle), cutting their engines/thrust at exactly the right moment, letting gravity slow the plane and allowing them to be more or less caught in mid air (a technological feat, granted, but I’d think feasible with our minds put to the task). I’m also ignoring the incredible stress level pilots would experience (“holy f##@$ holy f*%# holy f%@! holy f%%%$#$#@!!!!!!!!!!!! ………………. it worked!??!!!?!?”).

    I’m not sure what other architectural changes could be made, but we have advanced the state of technology and have extremely powerful computers compared to those available in the 1960s, so let’s not stick to the limitations admitted to at the dawn of the nuclear age (we have production-level self driving cars on the road today… surely the military could begin to accomplish/develop something to put an aircraft at exactly the right point at exactly the right moment to be plucked out of the air?) – what exactly could computers help with?

    Finally – considering the increased use of drones today and the incredibly varied ways in which supporting, storing, powering and controlling them is different that our manned air fleet – how many changes could be made that would support a drone-only carrier? Given that we could probably even have a heavier-than air flight path for this type of carrier, could it even be somewhat practical?

  5. Me Says:

    God, the Helicarrier is awesome

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