A whifferdill turnhttp://www.e-publishing.af.mil/pubfiles/pacaf/11/pacafi11-201/pacafi11-201.pdf#search=%22whifferdill%20turn%22 (obsolete, error 404) (also wolferdil, whiferdill, or (chiefly

Canadian Canadians (french: Canadiens) are people identified with the country of Canada. This connection may be residential, legal, historical or cultural. For most Canadians, many (or all) of these connections exist and are collectively the source of ...

British British may refer to: Peoples, culture, and language * British people, nationals or natives of the United Kingdom, British Overseas Territories, and Crown Dependencies. ** Britishness, the British identity and common culture * British English, ...

) whifferdale or wifferdale manoeuvre) is any of a number of fancy

aerobatic maneuver Aerobatic maneuvers are flight paths putting aircraft in unusual attitudes, in air shows, dogfights or competition aerobatics. Aerobatics can be performed by a single aircraft or in formation with several others. Nearly all aircraft are capab ...

s performed in an aerial flight show or while flying aggressively. It is a turn with both horizontal and vertical components, usually performed at the end of one maneuver in preparation for the next. As the plane is climbing the pilot makes a turn reversal, and as the plane descends it is turned so that it can make its next maneuver.

Aviator An aircraft pilot or aviator is a person who controls the flight of an aircraft by operating its Aircraft flight control system, directional flight controls. Some other aircrew, aircrew members, such as navigators or flight engineers, are al ...

s often use the term as

slang Slang is vocabulary (words, phrases, and linguistic usages) of an informal register, common in spoken conversation but avoided in formal writing. It also sometimes refers to the language generally exclusive to the members of particular in-gro ...

for any multi-axis movement or comical / interesting / unusual movement. The whifferdill is a basic

aerial warfare Aerial warfare is the use of military aircraft and other flying machines in warfare. Aerial warfare includes bombers attacking enemy installations or a concentration of enemy troops or strategic targets; fighter aircraft battling for control o ...

maneuver that is used to reverse course in a

dogfight A dogfight, or dog fight, is an aerial battle between fighter aircraft conducted at close range. Dogfighting first occurred in Mexico in 1913, shortly after the invention of the airplane. Until at least 1992, it was a component in every majo ...

with very little loss of energy/airspeed. It is also a fundamental maneuver used in

air show An air show (or airshow, air fair, air tattoo) is a public event where aircraft are exhibited. They often include aerobatics demonstrations, without they are called "static air shows" with aircraft parked on the ground. The largest air show m ...

Astronautics

astronautics Astronautics (or cosmonautics) is the theory and practice of travel beyond Earth's atmosphere into outer space. Spaceflight is one of its main applications and space science its overarching field. The term ''astronautics'' (originally ''astronaut ...

, a whifferdill is a maneuver used during

orbital rendezvous A space rendezvous () is a set of orbital maneuvers during which two spacecraft, one of which is often a space station, arrive at the same orbit and approach to a very close distance (e.g. within visual contact). Rendezvous requires a precise ma ...

when the target is on a different orbital plane from the piloted vehicle. Due to the nature of orbits, the target will seem to make a

helical Helical may refer to: * Helix, the mathematical concept for the shape * Helical engine, a proposed spacecraft propulsion drive * Helical spring, a coilspring * Helical plc, a British property company, once a maker of steel bar stock * Helicoil A t ...

motion relative to vehicle as the orbit progresses. A wifferdill maneuver is used to quickly realign the orbital plane of the vehicle with the target and stay near the target's orbital position or

mean anomaly In celestial mechanics, the mean anomaly is the fraction of an elliptical orbit's period that has elapsed since the orbiting body passed periapsis, expressed as an angle which can be used in calculating the position of that body in the classical ...

. Due to the short time and positional requirements, the maneuver uses a significant amount of fuel and can be difficult to execute successfully. In the case of

Gemini 10 Gemini 10 (officially Gemini X) With Gemini IV, NASA changed to Roman numerals for Gemini mission designations. was a 1966 crewed spaceflight in NASA's Gemini program. It was the 8th crewed Gemini flight, the 16th crewed American flight, and t ...

the need for the maneuver was a result of misalignment of the inertial guidance platform, causing axial drift of the approach trajectory, prior to closing to docking distance.

References

{{Aerobatics Aerobatic maneuvers