• 热门标签

当前位置: 主页 > 航空资料 > 飞行资料 >

时间:2011-01-28 16:05来源:蓝天飞行翻译 作者:admin
曝光台 注意防骗 网曝天猫店富美金盛家居专营店坑蒙拐骗欺诈消费者

a path for the inoperative side fuel to reach the
operating engine.
5. Wing box-beam tank vent valves open and equalize
the pressure above the fuel in each wing boxbeam
tank, permitting the higher static pressure
created by the full wing box-beam tank on the
inoperative side to induce flow through the open
sump tank interconnect valve to the operating engine.
6. Both defuel/tmnsfer selector valves open and allow
either wing or external tank fuel to transfer
into either wing box-beam tank.
If no crew action is taken with the FEED switch, the
same fuel system functions are automatically provided
when the thermistor in either cell No. 2 or 5 is uncovered.
Additional actions that will occur when the cell
No. 2 or 5 thermistor is uncovered are:
1. Both right and let? fuselage motive flow shutoff
valves open, overriding any previous commands
to close. Manual override of each valve is still
provided through the FEED switch.
2. Engine crossfeed valve receives a redundant command
to open. An initial command was provided
when the FUEL PRESS caution light illuminated.
ORIGINAL 2-54
NAVAIR 01.Fi4AAD-1
3. WING/EXT TRANS switch will automatically go
to AUTO if originally in OFF. If desired, OFF can
be reselected after 5 seconds.
2.14.6.1 Sump lank Interconnect Valve Failure.
The major fuel system consideration while operating
single engine is that the sump tank interconnect valve
opens when commanded. This constitutes the only path
through which inoperative side fuselage fuel can reach
the operating engine. While tbe probability of an inoperative
sump tank interconnect valve is very low, the
consequenceosf a malfunctionunder single-enginec onditions
are severe, particularly at landing fuel weights.
With a failed closed sump tank interconnect and full
tltselage cells on the inoperative side, only the wing titel
on the inoperative side and external fuel can be transferred
into the operating side fuselage. Attempts to
transfer the fuel from the inoperative side with the FEED
switch compound the problem when the motive flow
isolation valve and inoperative side motive flow shutoff
valve open. Operating side motive flow fuel, pumped
through the open motive flow isolation valve to permit
inoperative side wing and/or fuselage motive flow tmnsfer
cannot be retrieved. Fuel migration is approximately
100 pcunds per minute because of wing transfer, and
approximately 200 pounds per minute for fuselage
transfer. Coupled with a normal engine demand of approximately
100 pounds per minute, a balancing attempt
will result in usable fuel in the operative side being
depleted at approximately 400 pounds per minute.
Note
Operating side fuel remaining can be protected
by pulling the FUEL SHUT OFF handle
for the inoperative side and concurrently
selecting the operative side on the FEED
switch. This will eliminate a potential fuel
path acmss the engine automatic cmssfeed
valve, through the inoperative sump tank
boost pump into the inoperative side.
If the sump tank interconnect is failed closed, the
following additional considerations apply:
With the FEED switch selected to the operating side.
1. Wing and external tank fuel from both sides will
transfer into the operating side fuselage ifrhe inoperative
sidehelage is jLII.
2. IfDIMP is selected,w ing motive flow is automatically
activated; therefore, approximately 100
pounds per minute of fuel available to the operating
engine will be lost.
2.14.7 F~ei Dump. Figure 2-35 shows aircraft
fuel system components associated with fuel dump
operation.F uel dump standpipesin the fonvard(cellNo.
2) aud aft (cell No. 5) fuselage tanks are connected to
the fuel dump manifold at the dump shutoff valve. The
manifold extends aA to the fuselage boattail. Actuation
of the fuel DUMP switch to DUMP supplies power (dc
essential No. 2) to open the solenoid-operated pilot
valve, which ports motive flow till pressureto opent he
dump shutoff valve with weight off the main landing
geara nd the speedbrakesre tracted.
The fuel DUMP switch circuit is deactivatedo n deck
or with speedbrakes extended. Fuel dump with the
speedbrakeesx tendedi s inhibited becauseo f the resulting
flow field disturbance, which would result in fuel
impingement on the fuselage boattail and exhaust muzles.
T he speedbrakes witch is electricallybypassedduring
a combined hydraulic system failure, enabling the
pilot to dump fuel when the speedbrakesa m floating.
The electrical bypass is accomplished whenever the
combined pressure falls below 500 psi.
 
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址:F-14D 飞行手册 Flight Manual 1(86)