Only heavier aircraft such as the Boeing 747 have to dump fuel if they have full tanks when they must make an emergency landing. Otherwise they cannot land because the plane is too heavy.
Medium-sized aircraft such as the Boeing 737, and smaller aircraft types, need not dump fuel in case of an emergency landing, since the difference between maximum take-off and landing weight is relatively small. In addition, they lack the technical ability to dump fuel.
Fuel evaporates before reaching the ground
In cases where an aircraft must dump fuel, the pilot should preferably be directed to a flight path or area located over water. If this is not possible, then dumping should occur over an unpopulated area and from an altitude of at least 6,000 ft (1,850 m). This gives the fuel time to evaporate before reaching the ground.
It is difficult to determine the exact area affected by fuel dumping in such a situation, because this depends on the quantity of fuel that is dumped, the speed of dumping, wind, temperature and humidity.
Whirlwinds can be mistaken for dumping
A meteorological phenomenon in the form of whirlwinds may occur during landing, which is sometimes mistakenly interpreted as fuel dumping. All aircraft leave whirlwinds behind them, and when the weather is humid outside, they are visible due to the condensation of water vapour in the air. A whirlwind behind an aircraft is called a vortex.
Facts about fuel dumping
| 2010 |
So far, two fuel dumpings have occurred during 2010
(one over the Baltic Sea north of Gotland and one in Gävle Bay). |
| 2009 |
no fuel dumping occurred |
| 2008 |
one fuel dumping occurred |
| 2007 |
no fuel dumping occurred |