Aviation Turbine Fuel (ATF)

Aviation Turbine Fuel (ATF) is dispensed from specially designed refuellers, which are driven up to parked airplanes and helicopters. Major airports have hydrant refuelling systems that pump the fuel right up to the filling outlets on the tarmac through underground pipelines for faster refuelling. Essentially, ATF is pumped into an aircraft by two methods: Overwing and Underwing. Overwing fuelling is used on smaller planes, helicopters, and piston-engine aircraft and is similar to automobile fuelling - one or more fuel ports are opened and fuel is pumped in with a conventional pump.

Air Traffic Control (ATC)

Air traffic control (ATC) is a service provided by ground-based controllers who direct aircraft on the ground and in the air. The primary purpose of ATC
systems worldwide is to separate
aircraft to prevent collisions, to
organize and expedite the flow of
traffic, and to provide information and other support for pilots when able.
Preventing collisions is referred to as separation, which is a term used to prevent aircraft from coming too close
to each other by use of lateral, vertical
and longitudinal separation minima;
many aircraft now have collision avoidance systems installed to act as a backup to ATC observation and
instructions. In addition to its primary
function, the ATC can provide
additional services such as providing
information to pilots, weather and
navigation information and NOTAMs (NOtices To AirMen). In many countries, ATC services are
provided throughout the majority of
airspace, and its services are available
to all users (private, military, and
commercial).

Auxiliary Power Unit (APU)

An auxiliary power unit (APU) is a device on a vehicle that provides
energy for functions other than
propulsion. They are commonly found
on large aircraft, as well as some large
land vehicles.
The primary purpose of an aircraft APU
is to provide power to start the main
engines. Turbine engines must be accelerated to a high rotational speed
in order to provide sufficient air
compression for self-sustaining
operation. Smaller jet engines are
usually started by an electric motor,
while larger engines are usually started by an air turbine motor. Before
engines are to be turned, the APU is
started, generally by a battery or hydraulic accumulator. Once the APU is running, it provides power (electric, pneumatic, or hydraulic, depending on the design) to start the aircraft's
main engines.

VERY HIGH FREQUENCY OMNI-RANGE

VOR (VHF Omni-Range) is the basic
Electronic navigation that in use
today . This VHF Omni-Range
navigation method relies on the
ground based transmitters which
emitted signals to VOR receiver. The VOR system operates in the VHF
frequency band , from 108.0 to
117.95 MHz. The reception of VHF
signals is a line of sight situation . You
must be on the minimum altitude of
1000 feet (AGL) above ground level in order to pick up an Omni signals
service range.

OPERATION
The VOR facility at ground base
transmits two signals at the same time.
One signal is constant in all directions
as a reference phase. Another signal, it
is variable-phase signal and it rotates
through 360 degrees, like the beam from the lighthouse. Both signals are
in phase when the variable signal
passes 360 degrees (reference to
magnetic north) and they are 180
degrees out of phase when the
rotating signal passes 180 degrees The aircraft equipment receives both
signals. The receiver will calculate the
difference between the two signals,
and interprets the result as a radial
from the station to pilots on the
aircraft.
RADIALS: The two signals from VOR
transmitter generate 360 lines like
spokes in a wheel . Each line is called a Radial . VOR navigation equipment on the airplane will determine which of
those 360 radials the airplane is on.