How are fuel tanks constructed?

Two technologies are used to make fuel tanks for automobiles: Metal (steel or aluminum) fuel tanks welded from stamped sheets. Plastic high-density polyethylene (HDPE) fuel tanks made by blow molding.

What happens to drop tanks when jettisoned?

When a drop tank is jettisoned, very likely it is not retrieved and reused. This is also the case with (sadly, discontinued) Space Shuttle external tank. Those tanks were not reused either.

What can fuel tanks be constructed from?

Typically, plastic fuel tanks are made from these five different materials: high density polyethylene (HDPE), polypropylene (PP), regrind plastic (recycled polyethylene), a plastic adhesive or ethyl vinyl alcohol (EVOH).

How are plastic fuel tanks made?

Plastic tanks are formed by blowing a thick continuous tube of HDPE within a mold that determines the final shape of the virtually seamless part, which could include the filler neck.

What happens to the external fuel tank after separation?

During launch, tank and boosters are jettisoned and fall back to Earth after a shuttle’s initial push to the sky. Unlike the boosters, however, the external tank is not collected and reused. Instead, the tanks are discarded to burn up in Earth’s atmosphere.

Are fuel tanks pressurized?

The fuel tank is supposed to be pressurized so that gasoline vapors can be controlled and captured, rather than released into the atmosphere.

Are plastic fuel tanks safe?

Plastic tanks are about 30 per cent lighter, and they generally don’t have seams, which makes them less likely to rupture in a crash. Plastic fuel tanks are very tough. (It’s hardly as if a plastic tank is a glorified Coke bottle.) It’s even a better insulator if there’s a fire beneath the vehicle.

What happens to fuel tanks when they are empty?

In real combat, external fuel tanks are jettisoned when empty or as soon as the aircraft needs to get rid of them to accelerate and maneuver against an enemy fighter plane or to evade a surface to air missile. Several thousand drop tanks were jettisoned over Southeast Asia during the Vietnam War.

What is the purpose of external fuel tanks?

External tanks are extremely important for military aircraft as they provide fuel to integrate internal tanks and extend fighters and bombers endurance. Indeed, even if they can be refueled by aerial tankers, tactical jet planes heavily rely on the JP-8 fuel loaded on the external fuel tanks.

What happens to the external tank during launch?

Image left: An External Tank falls back to Earth after being jettisoned from the Shuttle. Click image to play video of External Tank separation (no audio) Photo credit: NASA. The tank is also the “backbone” of the Shuttle during the launch, providing structural support for attachment with the solid rocket boosters and orbiter.

Can a tactical jet refuel with an auxiliary fuel tank?

Indeed, even if they can be refueled by aerial tankers, tactical jet planes heavily rely on the JP-8 fuel loaded on the external fuel tanks. However, the auxiliary fuel tanks represent an additional weight, additional drag, and they will reduce the aircraft maneuverability.