Immelmann turn
1. Level flight.
2. Half loop.
3. 180° roll to bring aircraft back level.
The Immelmann Turn refers to two quite different aircraft maneuvers. The maneuver nowadays usually called an "Immelmann" has in fact no connection with the World War I German flying ace Max Immelmann.
In Aerobatics
In modern aerobatical parlance, an Immelmann turn (also known as a roll-off-the-top, or simply an Immelmann) is an an aerobatic maneuver, of little practical use in aerial combat, and in fact is a different maneuver altogether from the original dogfighting tactic of the First World War from which it derives its name. Essentially, it comprises a half loop followed by a half roll.
To successfully execute the aerobatic Immelmann turn, the pilot accelerates to sufficient airspeed to perform a loop in the aircraft. The pilot then pulls the aircraft into a climb, and continues to pull back on the controls as the aircraft climbs. Rudder and ailerons must be used to keep the half-loop straight when viewed from the ground. As the aircraft passes over the point at which the climb was commenced, it should be inverted and a half loop will have been executed. Sufficient airspeed must be maintained to recover without losing altitude, and at the top of the loop the pilot then executes a half-roll to regain normal, upright aircraft orientation. As a result, the aircraft is now at a higher altitude and has changed course 180 degrees.
It should be stressed that not all aircraft are capable of (or certified for) this maneuver, due to insufficient engine power, or engine design that precludes flying inverted (usually piston engines that have an open oil pan).
The Immelmann has become one of the most popular aerobatic maneuvers in the world, being commonly used in airshows all across the globe. However, the aerobatic maneuver is of little use in modern dogfighting, due to the fact that modern high thrust fighters can quickly initiate sustained vertical maneuvering from level flight, and slow targets are highly vulnerable to air-to-air missiles. The aerobatic maneuver also involves rapid "energy loss" (loss of airspeed) even if the nose is pushed down sharply as the maneuver is completed (This maneuver, an aerobatic Immelman followed by a dive back to the original altitude is another aerobatic maneuver called the "Half-Cuban-Eight").
Historical combat maneuver
In any case, the World War I "Immelmann turn" was a far less polished maneuver. This attacking maneuver was used frequently by Max Immelmann and later by other World War I fighter pilots. After making a high speed diving attack on an enemy, Immelmann would then zoom climb back up past the enemy aircraft, and before stalling used full rudder to yaw (maneuver around the aircraft's "normal axis") his aircraft around. This put his aircraft facing down at the enemy aircraft, making another high speed diving pass possible. This is a difficult maneuver to perform properly, as it involves precise control of the aircraft at low speed. With practice and proper use of all of the fighters controls, the maneuver could be used to re-position the attacking aircraft to dive back down in any direction desired. This form of "Immelmann turn" was called Renversement by French pilots. The modern aerobatic maneuvers that most resemble the WW I Immelmann are the "wingover", and the "hammer-head turn".
The WW I Immelmann tactic fell into disfavour between the World Wars, as combat aircraft engines grew increasingly powerful, and the zooming aircraft could be followed by his adversary, and presented an easy target as it hung nearly motionless at the top of the maneuver. The Immelmann could still be used in World War II by fighters attacking unescorted bombers that could not follow the fighter up into the climb, as long as the zoom climb took the fighter beyond the range of the bomber's defensive guns.
Trivia
 | This article contains a list of miscellaneous information. (October 2007) |
- Singer-songwriter Al Stewart included a song entitled "The Immelman Turn" on his 2005 album A Beach Full of Shells.
- Claus Valca of the anime Last Exile gets nicknamed "Immelmann" by Dio Eraclea for his successful execution of an Immelmann turn.
- In the climax of the 1983 movie Blue Thunder, main character Frank Murphy (Roy Scheider) uses an Immelmann turn with his helicopter to defeat his arch enemy Col. Cochrane (Malcolm McDowell).
- In the PC video game H.E.D.Z., the 'hed' player characters that possess the ability of airplane flight can perform an Immelmann Turn using the special controls.
See also
References
This article has been simplified for civilian reference.