Fuel starvation

Fuel starvation and fuel exhaustion (sometimes referred to as fuel depletion) are problems that can affect internal combustion engines fuelled by either diesel, kerosene, petroleum or any other combustible liquid or gas. If no fuel is available for an engine to burn, it cannot function. All modes of transport powered by such engines can be affected by this problem, but the consequences are most significant when it occurs to aircraft in flight. Ships are affected to a lesser extent – with no propulsion, they cannot maneuver, and are at risk for collisions or beaching.

An important distinction is the mechanism behind fuel starvation:

Fuel leaks can be considered as a third kind of fuel starvation: The airplane starts off with sufficient fuel, but yet it does not reach the engines.

There are two main ways that an engine can run out of fuel:

Fuel starvation is slightly different from fuel exhaustion, in that fuel is in the tank but there is a supply problem which either fully or partially prevents the fuel from reaching the engine. Causes may include a blocked fuel filter, problems with fuel tank selection if multiple tanks are installed, or more commonly water-contaminated fuel. Fuel has a lower specific gravity than water which means that any water in the fuel will collect in the bottom of a fuel tank. As fuel is typically drawn from the lowest part of the tank, water is delivered to the engine instead and the engine starves.

Many incidents have happened on aircraft where fuel exhaustion or starvation played a role. A partial list of these incidents follows:

A number of aircraft have been abandoned by their crew (both intentionally and sometimes accidentally) when the aircraft has continued on its own until fuel exhaustion caused it to crash:

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