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Dumb question, feel free to ridicule me: Most aircraft keep fuel in their wings, but said wings are thin because fuel is not under (high) pressure. Why can't we

Dumb question, feel free to ridicule me: Most aircraft keep fuel in their wings, but said wings are thin because fuel is not under (high) pressure. Why can't we have thicker wings, or thinner tanks, that can accommodate hydrogen vessels?

Ourgon 5y ago
The answer is air resistance which increases with the third power of the object speed. Airships are fairly slow which allows this type of design. Passenger or freight jets are supposed to be fast, this being their major appeal over ship and rail transport.
kurthr 5y ago
I think for safety and convenience, they're likely to use the upper portion of the fuselage for storage. That way, if there is a leak... it goes up and out. https://cleantechnica.com/2022/01/12/money-talks-zeroavia-nails-paine-field-site-for-hydrogen-aircraft-rd/ https://cleantechnica.com/2022/01/12/money-talks-zeroavia-na...
- ncmncm 5y ago
  It will be assumed there are leaks at all times, and positive airflow will be maintained to eliminate possibility of ignition. But the fuel probably should be stored liquified in outboard nacelles, anyway.
Hnrobert42 5y ago
The article describes “dry” wings which allows for more flexibility and some other benefits. The fuel is stored, depending on the model, under the fuselage or at the rear of the aircraft.
carabiner 5y ago
Thinner tanks would have to be strengthened and heavier because they're under pressure and the non-spherical shape leads to higher stresses. It'd be like building a main cabin shaped like a square; the volume to weight ratio would suffer. Thicker wings... this would have major reductions in performance. For cruising speeds of today, thinner airfoils are favored for low drag at supercritical speeds. Airfoil design is delicate and minute changes in the shape can dramatically affect the performance (operating cost) of the entire aircraft. Biggest tradeoff in commercial aircraft design is operating cost vs. everything. Anything can fly with a big enough engine on it, even a lead block. That's not the challenge. Minimizing cost per passenger-mile though is everything.

Ourgon 5y ago

The answer is air resistance which increases with the third power of the object speed. Airships are fairly slow which allows this type of design. Passenger or freight jets are supposed to be fast, this being their major appeal over ship and rail transport.

kurthr 5y ago

I think for safety and convenience, they're likely to use the upper portion of the fuselage for storage. That way, if there is a leak... it goes up and out. https://cleantechnica.com/2022/01/12/money-talks-zeroavia-nails-paine-field-site-for-hydrogen-aircraft-rd/ https://cleantechnica.com/2022/01/12/money-talks-zeroavia-na...

ncmncm 5y ago
It will be assumed there are leaks at all times, and positive airflow will be maintained to eliminate possibility of ignition. But the fuel probably should be stored liquified in outboard nacelles, anyway.

Hnrobert42 5y ago

The article describes “dry” wings which allows for more flexibility and some other benefits. The fuel is stored, depending on the model, under the fuselage or at the rear of the aircraft.

carabiner 5y ago

Thinner tanks would have to be strengthened and heavier because they're under pressure and the non-spherical shape leads to higher stresses. It'd be like building a main cabin shaped like a square; the volume to weight ratio would suffer. Thicker wings... this would have major reductions in performance. For cruising speeds of today, thinner airfoils are favored for low drag at supercritical speeds. Airfoil design is delicate and minute changes in the shape can dramatically affect the performance (operating cost) of the entire aircraft. Biggest tradeoff in commercial aircraft design is operating cost vs. everything. Anything can fly with a big enough engine on it, even a lead block. That's not the challenge. Minimizing cost per passenger-mile though is everything.