Aircraft
control surfaces
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An
essential element in a pilot’s safe completion of a flight is the control of
his aircraft. The pilot of an aircraft
must be able to accurately control an aircraft in three axes. Those axes are pitch, roll, and yaw, or
nose-up--nose-down, lean-left--lean-right and nose-left--nose-right.
The
primary control for an aircraft to climb or descend is the horizontal control
surface at the rear of the aircraft called the elevator or stabilator. An elevator is a movable control surface
attached to the horizontal stabilizer of the aircraft. Moving the wheel or stick of the aircraft
forward or back makes the elevator move down or up. When the elevator moves
down, increased wind force impinging upon it pushes the tail up, pitching the
nose of the aircraft down. When it moves up, the opposite happens. Pulling back
on the control wheel thus causes the nose of the aircraft to pitch upward. In a
climb, the aircraft’s nose is held in a position above the relative horizon,
causing the aircraft to assume a climb attitude. Pushing forward on the control
wheel of the aircraft causes the aircraft to descend.
A
secondary control surface connected to the elevator is the trim tab. The trim
tab is a movable surface that causes the elevator to remain in a set position,
making it unnecessary to hold constant pressure on the control wheel to
maintain a constant pitch attitude. Most aircraft can be flown with fingertip
pressure if trimmed properly.
A
stabilator acts in the same way as an elevator,
however the entire horizontal surface of the tail moves, providing a greater
control authority.
The
second major control surfaces are the ailerons. These are connected to the
outboard sections of the wings and provide the pilot with an ability to control
the rolling or banking of the aircraft. The ailerons are also controlled by the
movement of the control wheel or stick in the cockpit of the aircraft. The
ailerons cause the aircraft to bank by changing the camber or shape of the
wing.
If
a bank to the right is desired, the pilot turns the wheel of the aircraft to
the right, deflecting the aileron on the left wing downward, which increases
the lift on that wing.
The
aileron on the right wing simultaneously deflects upward, causing that wing to
lose lift. This unequal lift will cause
the aircraft to roll in the desired direction.
After the desired angle of bank is achieved, the pilot returns the
control wheel to the original neutral position.
The aircraft will maintain the angle of bank until the pilot rolls the
aircraft back to wings-level.
Some
aircraft provide roll control by the use of spoilerons. These panels on the upper side of the wing
deflect upon the movement of the control wheel.
If the control wheel is moved to command a right turn, the spoileron on the right wing will extend, spoiling the lift
on that wing and causing it to drop.
The
third control surface is the rudder of the aircraft. The rudder controls the
aircraft in the yaw axis.
The
rudder is connected to the rudder pedals on the floor of the aircraft.
By
pushing on the right or left rudder pedals the pilot will deflect a movable
surface connected to the vertical stabilizer of the aircraft, which causes the
nose of the aircraft to “steer” right or left.
The
use of right rudder compensates for the tendency of the aircraft to turn to the
left when full power is used on takeoffs.
The
rudder also is used to overcome the adverse yaw caused by a downward deflected
aileron when banking and when landing in a crosswind.
During
the late 1940s and early 1950s, an aircraft called the Ercoupe
was produced with no rudder pedals. This
aircraft was billed as being as easy to fly as driving an automobile.
The
landing gear was designed to caster, enabling the aircraft to land in a crabbed
attitude during crosswind landings.
These
control surfaces; the elevator, the ailerons, and the rudder, when used in
concert, allow the pilot of the aircraft to control the attitude of the
aircraft with a great deal of precision.
Airport Authority meets
The
December meeting of the Santa Ynez Valley Airport Authority was held on Dec. 6
at the airport administration building.
The meeting was called to order at 7 p.m. by Chairman Chamberlin.
Attending
the meeting were board officers: President James Kunkle,
Secretary Aggie Margolis, and Vice-President Garth Carrier. Directors Jeff Hecker,
Tom Petersen, and Bob Leite were also in attendance.
The
treasurer’s report detailed the receipt of an additional $3,000 in revenue for
the month of December from Conde Nast Magazine for a
photo shoot for Dillards Department Stores. The airport authority charges $1,500 per day
for special uses such as commercial shoots or other non-aviation commercial
uses.
In
other business, the board received a report of the receipt of an application
for a commercial use license from Light Sport Airplanes West to operate a light
sport aircraft dealership out of Santa Ynez Airport. Upon completion of the application and
verification of insurance, the application will be handled administratively by
the airport management.
Airport
consultant Kim Joos reported a change in insurance
companies providing directors and officers liability
insurance.
During
a report on the status of the airport’s conditional use permit, Chamberlin
reported that there was some misinformation in the public discussion from local
activist groups regarding the county’s disinclination to perform an
environmental impact report. Chamberlin
was to attend a meeting of the Central Coast Water Board to assist in clearing
misunderstandings regarding the county’s past position
on the EIR.
An
update on the new webcam and airport website shows that between 12,000 and
17,000 “hits” are being recorded each day.
The live webcam and airport information can be viewed at www.santaynezairport.com.
Airport
manager Kunkle provided an update on the continuing
problem with the sealant applied to the ramp areas.
Testing
showed that the sealant contained water content far higher than what was
allowed by the manufacturer or the specifications for the sealant. Additional testing is being done and a
solution is in the works.
The
next meeting of the airport authority will be held on Jan. 3 at 7 p.m.