Modificatie Flight Controls - Portfolio Matthijs van Essen

Modificatie flight controls 2a1ap Aviation Studies
Summary
Project team 2A1AP has got the task from Amsterdam Leeuwenburg Airlines (ALA) to do a research if
it is profitable to do a modification from a conventional to a fly-by-wire system.
The principles of a flight rests on the aerodynamics. The two main aerodynamic laws are the law of
Bernoulli and the law of continuity. The law of Bernoulli is also known as the law of conservation of
energy or the law of conservation of volume. With the law of Bernoulli it is possible to see what is the
relationship between the speed en the pressure of a flow.
The wing of an airplane generates lift. Flight controls makes it possible to let the airplane turn around
three axes. The ailerons will let the airplane turn around its longitudinal axis, the elevator around its
lateral axis and the rudder around its vertical axis. There are four forces on an airplane during a
flight: the trust, drag, lift and weight.
There are two sorts of flight controls: the primary and the secondary. The primary flight controls are
the aileron, rudder and the elevator. The three movements around the three axes are called: to roll,
to pitch and to yaw. The secondary flight controls are the flaps, slats, spoilers en the trim. These controls
supports the primary flight controls. The flight controls are driving by hydraulic systems. The
European Aviation Safety Agency (EASA) has put requirements to improve the safety of the airplanes.
One of these requirements is that there has to be a back-up system that can take over a system
where is occurred an error.
There are two ways to let the flight controls be functional. This can be done by a conventional system
or by a fly-by-wire system. The conventional system uses a control column to move the flight controls.
The movements of the control column has to be convert to a signal. This conversion is done by
cables and pulleys by the elevators. The hydraulic network consists of three hydraulic systems. Two
of these has their own drivetrain. The third one is a back-up system. Each primary flight control has
their own back-up system.
The fly-by-wire system uses electrical signals and a side-stick to move the flight controls.
An advantage of the conventional system is that the pilot feels a pressure on the control column. A
big disadvantage of the conventional system is the wear of the moving mechanic parts.
During the modification it is necessary to bear different factors in mind like the costs, safety and durability.
To do the modification during a D-check will cut down the costs. After a research it appeared
that the airplane would be meet to all requirements after a modification. Referring to a cost volume
profit analysis it appeared that a modification is not profitable. The break-even-point will be obtained
after 42 years. In this period the life span of an airplane will be exceeded.
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