Vulching covers a variety of unacceptable attacks against other pilots online when they are unable to properly defend themselves. In the most traditional sense, vulching is defined as an attack against another player that is on the ground. This term generally includes aircraft which are landing, or have just taken off.

This is extremely frowned upon, and, when done online, may result in:

The circumstances determine the severity of the offence. If two pilots are dogfighting while spawning on the ground, it is fair to attack whenever the other pilot's wheels are off the ground. If a pilot is not already engaged, he should be allowed to climb at least 500ft before attacking, unless he does not intend to climb that high. If a pilot has declared his intent to land, he should be left alone. Attacking civilians without their permission is generally forbidden, and attacking a civilian aircraft while it is on the ground, landing, or taking off, is the worst form of vulching.

It is not vulching to attack player controlled tanks, anti-aircraft vehicles, or ships on ground, since these vehicles cannot fly. A player may be freely attacked on the ground after he has fired weapons at someone from the ground - this is also not considered vulching, because one may always immediately return fire.