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
suppliers assisted by providing data on equipment returned for shop repair.
This chart shows the scope of activities and data gathering performed by the Airbus AWG:
3-2: Scope of Airbus Data Gathering
The items contained in the Airbus inspection documents were the list as drawn up by all the
AFSSP-participant manufacturers and promulgated to each of the product-line subgroups. Where
items were particular to Airbus, separate documentation were issued, i.e., the decision was taken
to implement a one-time rework of some the pipe work on the A300 and A320 family rather than
carry out an inspection.
During the scheduled maintenance of one aircraft, model A300 /B4, MSN 161, an unexpected
number of bonding leads (or jumpers) were found damaged in a localized area. This discovery
initiated an investigation, the results of which were fed back into the AFSSP. The resultant action
was for the Airbus AWG to issue a dedicated visual/tactile inspection service bulletin (SB) for
bonding leads. The voluntary inspection items and bonding checks were included in the service
information letter (SIL).
Airbus Working Group activities
Modification SBs
Pipe-work and one
particular FQIS
equipment; onetime
rework of the
bonding
Inspection SBs
Bonding leads—
visual and tactile
inspections
Service information
letter (SIL)
Bonding lead, tank
structure, and in-tank
equipment inspection
(including bonding
measurements)
Equipment supplier
shop return data
- Boost pumps
- FQIS probes and
harnesses
- Pressure switches
- Level sensors
3.0 Airbus Working Group Report (continued)
Page 20 Industry AFFSP Report August 4, 2000
At the request of AWG airline members, the ISB and SIL inspection requirements were combined
in one document. As a result, the SIL incorporated all the requirements of the ISB, which meant
that operators who accomplished SIL inspections were also credited with accomplishing the ISB.
3.5 Inspection Criteria
The inspections were carried out during scheduled fuel tank entry intervals. For Airbus aircraft,
fuel tanks are typically opened up every 4 to 5 years for routine inspection tasks.
Although there were items unique to individual manufacturers, the following common set of items
was used by all manufacturers in the development of their respective inspection programs:
! Fault current bonding.
! Internal power wiring and insulation.
! Static and lightning bonding.
! Couplings.
! FOD and tank condition.
! FQIS wiring and probes.
! Flame arrestors.
Fault Current Bonding
Some of the manufacturers bond electrical components in the flammable and flammable-leakage
zones of the aircraft to fault current curves that are specified in or derived from MIL-B-5087B.
These curves were developed through testing. This level of bonding provides a very low resistance
path to ground, ensuring that any unintended ground paths, external to the equipment, are ignored
and that the circuit protective devices are able to activate appropriately. The MIL-B-5087B has
been superseded by MIL-464, which in turn refers to FAA Advisory Circular AC 20-53A to
define the protection requirements.
This advisory circular, while being specific to the lightning protection requirements of the fuel
system, also provides an appropriate design solution for short circuit fault current dissipation. The
Airbus approach is to ensure that sufficient cross-sectional area and alternate/redundant bonding
paths are incorporated into the design. Quality control over this build standard and in-service
maintenance actions (when components are replaced) is then maintained through bonding
verification checks in accordance with the original type certification requirements.
Where a bonding check is requested within the Airbus inspection program, the measured
resistance values were noted and compared with the initial build requirement leaving the factory.
If exceedances were recorded, the inspection documents instructed those bonds to be re-worked to
the initial build requirement.
3.0 Airbus Working Group Report (continued)
August 4, 2000 Industry AFFSP Report Page 21
Internal Power Wiring and Insulation
On all of the Airbus product line, power supply to boost pumps, which are 115 V AC, are routed
external to all the fuel tanks. Hence, within the Airbus inspection program, there were no
requirements to inspect external power wiring.
Bonding for Static and Lightning Protection
The integrity of the fuel tank is ensured during a lightning strike by demonstrating compliance
with the aforementioned advisory circular and other airworthiness guidance material. Areas inside
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：
航空资料3(68)
