Dictionary Definition
chandelle n : a flight maneuver consisting of a
steep climbing turn executed to gain altitude while changing
direction v : climb suddenly and steeply; "The airplane
chandelled"
User Contributed Dictionary
French
Pronunciation
- lang=fr|/ʃɑ̃.dɛl/
- SAMPA: /SA~.dEl/
Noun
chandelle (plural: chandelles)- candle
- candlelight
- aux chandelles - by candlelight or candlelit
Derived terms
Extensive Definition
The chandelle is an aircraft control maneuver
where the pilot combines a turn with a climb in a certain
way.
It is now required for attaining a commercial
flight certificate in many countries, including the FAA in the
United States.
The chandelle (which is the French word for
candle) is a precision aircraft control maneuver, and not strictly
speaking an aerobatic, dogfighting, or aerial combat maneuver. It
is rather a maneuver designed to show the pilot's proficiency in
controlling the aircraft while performing a minimum radius climbing
turn at a constant rate of turn (expressed usually in degrees per
second) through a 180 degree change of heading, arriving at the new
reciprocal heading at an airspeed in the "slow-flight" regime, very
near the aerodynamic stall. The aircraft can be flown in
"slow-flight" after establishing the new heading, or normal cruise
flight may be resumed, depending upon the purposes of the exercise
or examination. See the diagram below for a visual depiction of how
the maneuver must be flown for the purpose of certification.
The pilot enters a chandelle at a pre-determined
airspeed in the normal cruising range for the aircraft. The power
setting used is not changed during the chandelle until the recovery
stage, when it may be increased until the aircraft is
re-established at a normal cruising speed, at which point the power
is returned to a normal cruise setting. To begin the maneuver the
pilot first rolls the aircraft in the desired direction with the
controls (the ailerons), and quickly but smoothly establishes a
medium banked turn. In most small aircraft (cruising speeds of 100
- 175 KIAS) this bank will be about 30 to 40 degrees. This will
begin a turn of the aircraft in the direction of bank. Then a
smooth pitch up is started with the controls (the elevators on the
empenage). The angle of bank stays constant during the first 90
degrees of the change of heading, while the pitch angle increases
steadily. At the 90 degree point in the change of heading, the
aircraft has the maximum pitch angle (which should be close to the
critical angle of attack at the level stall speed of the aircraft).
During the second 90 degrees of the change of heading, the pitch
angle is held constant, while the bank angle is smoothly decreased
to reach 0 degrees of bank, the end of the turn and return to
straight-and-level flight at exactly the reciprocal (180 degrees
away from the heading at the start of the maneuver) heading, and
with the airspeed close to the stall speed. The aircraft should not
lose altitude during the last part of the maneuver, nor during the
recovery, when engine power may be used to re-establish normal
cruising speed on the new heading. The decreasing bank angle
together with the decreasing airspeed during the second half of the
chandelle will maintain a constant turn rate . The turn needs to be
kept coordinated by applying the correct amount of rudder
throughout the maneuver.
From a practical point of view the chandelle may
be used to turn an aircraft within a minimal turn radius. As such
it is a useful maneuver for pilots of small aircraft who find
themselves in a blind valley or canyon. 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 guns shot 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, who described it as monter en chandelle, "to climb around a
candle.", however it has since come to have a rather more strict
definition for pilot flight testing purposes. In early fighter
combat, a pilot would aim to achieve the maximum practical speed at
full throttle, then roll the aircraft to the required angle of bank
for the change of heading that was required in the combat
situation. As the turn began, the nose is increasingly pitched up,
as required for the amount or change of heading desired. As
described above the turn progresses with the desired pitch angle
and requisite rudder to control yaw, airspeed decreases, and then
the wings are leveled so as to roll out straight and level on the
new desired heading, all the while avoiding an aerodynamic stall.
At this point if the pilot has any more power it may be added to
regain airspeed, or the nose of the aircraft can be allowed to drop
somewhat to achieve the same effect(dropping the nose of the
aircraft is not permitted for the purposes of the maneuver in
commercial flight testing). In aerial combat the chandelle maneuver
was used both aggressively to position the aircraft for attack, and
defensively to evade an enemy.
FAA Publication FAA-H-8083-3A (Airplane Flying
Handbook)