 It was also, therefore, a useful maneuver to early fighter pilots in their low-powered aircraft to quickly turn toward a pursuing attacker (which would tend to make a tracking gunshot more difficult because of the turn and climb involved) while climbing but not stalling the aircraft, or to position themselves quickly to make an attack on a turning enemy or an enemy flying on another heading.French aviators during World War I described it as "monter en chandelle", or "to climb vertically".However, it has since come to have a rather more strict definition for pilot flight testing purposes.