In most cases, a missed approach is begun at or before the applicable DA or MDA for the approach being flown. Because any later decision to go around must have followed an earlier positive decision by PF to continue to a landing, it is often described as a rejected landing or a baulked landing, although neither term has any formal definition. It may or may not involve at least part of the landing gear contacting the runway and in extreme cases, touchdown may have occurred on all main landing gear units.