BOMBARDIER BD-100-1A10, Руководство по эксплуатации

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FUEL
Sep 13/2004 Flight Crew Operating Manual Volume 2
REV 1 CSP 100-6
12-01-05
FUEL TANK SYSTEM (Cont)
FLAPPER CHECK VALVES
Each wing tank incorporates flapper check valves that are attached to the internal wing ribs. These valves prevent outward
flow of the fuel during wing low maneuvers.
VENT SYSTEM
The tanks are vented through interconnecting vent lines to NACA scoops (low drag vents) located on the lower surface of
the wing trailing edges (one per wing).
During operations on the ground and in flight, the NACA scoops provide static ventilation of the tanks and relieve air pres-
sure differential caused by the refueling process, thermal expansion of the fuel, or altitude variation in flight.
Surge bays located outboard of both wing tanks provide additional expansion volume for the vent system to prevent fuel
spillage. Each surge bay holds 53.6 lbs of fuel and flapper valves are located between the surge bays and tanks to prevent
outward flow of fuel from the tanks.
FUEL DISTRIBUTION
DESCRIPTION
There are two separate fuel distribution systems. One feeds the left engine, and the other feeds the right engine and APU.
ENGINE FUEL FEED
The primary fuel feed to each engine is independently provided from its respective tank. The feed line is pressurized by
means of an ejector taking its motive flow from the high pressure stage of the engine fuel system. This high pressure fuel
is delivered to the ejector nozzle. The same high pressure source is also used to drive the scavenge ejector. The primary
ejector is totally self energized by its respective engine and is not reliant on any other power source for its control or oper-
ation. Proper operation of the primary feed ejector is signaled by a pressure switch located at the ejector outlet.
APU FUEL FEED
The APU fuel feed is established from the right collector tank to the APU by the right main ejector or by the right DC fuel
pump if the ejector pressure is low. This system includes an APU shutoff valve.
ELECTRIC FUEL PUMPS
The electric fuel pumps provide fuel pressure to the engines when the main ejector pumps cannot, such as during engine
start and main ejector pump failure. The electric fuel pumps also provide fuel pressure to transfer fuel from one wing tank
to the other.
COMPONENTS AND OPERATION
FUEL COMPUTER
A dual-channel fuel system computer calculates the onboard fuel quantity and controls the refueling. One channel controls
one side and the other channel controls the opposite side. If the onside channel fails, the other channel automatically as-
sumes control. Each channel receives signals from the probes and aircraft attitude information from the AHRS.
The computer calculates the fuel quantity as weight in each tank. The computer uses the following information:
fuel density, fuel probes readings, aircraft attitude and accelerations, and WOW signal.
MOTIVE FLOW
The ejectors operate by using motive flow pressure from the engine-driven pump. As high-pressure motive flow passes
through the venturi of the ejectors, fluid velocity is increased and low pressure is created. The suction caused by the low
pressure moves the fuel out of the tank.
SCAVENGE EJECTOR
The scavenge ejectors are operated by motive flow created by the high-pressure output of the engine-driven fuel pumps.
The two ejectors are located at the lowest inboard point of each wing tank. The ejectors transfer fuel from the wing tanks
to the collector tanks.