2004 Flight Operations Symposium Questions 8/23/2004 10:19 AM
May 9 – 12, 2004, Bell Harbor Convention Center
Page 1 of 15
757/767 Breakout Questions and Answers
Center Tank Fuel Pump Status:
1. How will the normal procedures be synchronized for the 757/767? Operators receive the revisions
to the 757 and 767 6 months apart and thus have to wait to update their ops manual.
<Answer>. Both sets of procedures will be published in both old and new versions, though the
publication dates will be staggered. The versions will be effective for about a year during
which time the airlines can synchronize on their own schedule.
2. Are there any plans to incorporate the 767 shared flow operations manual bulletin into the fuel
CONFIG operations manual procedure?
<Answer>. Boeing does not plan to do this. Airlines can modify their own books or they can contact
Boeing if they have a contract for plan 2 service. Please contact Boeing Flight Technical
Integration & Data to request that your operations manual bulletin be incorporated.
3. How big of a job is it to retrofit a scavenge system on the 767? Is there a Boeing service bulletin to
do this?
<Answer>. One operator has purchased a Master Change from Boeing to install scavenge systems on
their 767-200 airplanes. The service bulletin indicates approximately 40 hours of task
time (2 people at 20 hours) are required to install the system on these airplanes.
4. What is the projected cost of the Auto Shutoff SB? Will Boeing be providing the auto shutoff
service bulletin at a reasonable price?
<Answer>. Please be advised that the cost of retrofit for the auto shutoff system has not yet been
determined.
5. If auto shutoff will be considered an AMOC to the fuel pump AD which requires wet shutoff, why
is Boeing still pursuing a design change to the 767 fuel pumps? In other words, if installation of
the Auto Shutoff feature is terminating action to the AD and installation of the cast-in diffuser
pumps is another, why should an operator install both features? Why install cast-in diffuser
pumps? What is the cost of the Auto Shutoff?
<Answer>. The Auto shut-off feature is intended to minimize dry running of pumps. The machined
diffuser configuration of pumps has a failure mode within the pump which could cause an
ignition source in the pump. Boeing intends to ask for an AMOC for the wet shutoff
requirement, but the 1000 hour inspection will still be required. Current terminating
action for the AD (which removes the 1000 hour inspection) is installation of the cast-in
diffuser pump. The cast-in diffuser pump has performance issues, causing a premature
main tank fuel consumption anomaly. Boeing is continuing to investigate a redesign of
the pump in order to address the performance issues with the cast-in diffuser and relieve
the operators of the 1000 hour inspection with the machined diffuser pump.
2004 Flight Operations Symposium Questions 8/23/2004 10:19 AM
May 9 – 12, 2004, Bell Harbor Convention Center
Page 2 of 15
6. How big of a job will it be to incorporate the auto shutoff feature? Will it be true for both the 757
and 767?
<Answer>. Installation of the auto shutoff feature should only involve placing a couple of relays and
some wires in the EE bay and could be accomplished overnight. This would apply to
both the 757 and 767.
7. Will the auto shutoff feature require installation of new EICAS computers or result in new EICAS
messages? What will be done about the uncommanded ON pump?
<Answer>. There are no plans to add any new EICAS messages as EICAS changes are costly and
time consuming.
We are in discussions with the FAA at this time regarding the uncommanded ON
function and are currently unable to provide any details on this issue.
8. Regarding AD 2002-19-52 for the 757 airplane, what is the inspection interval?
<Answer>. There is no established inspection interval. When a pump is first inspected it is identified
with a special suffix. Each time after that the pump is reworked it must be re-inspected
with a boroscope.
9. Will the auto shutoff feature prevent the metal to metal contact on the 767?
<Answer>. Auto shutoff does not prevent the metal to metal contact within the pump. The auto
shutoff feature will minimize the dry running of pumps to 14 seconds. The current AD
mandates a 1000 hour inspection which will ensure that there are no liberated parts within
the pump.
10. Is this a change in philosophy? There seems to be a contradiction between the current procedure
to turn the pumps off at 500kg and the Auto Shutoff that waits until a low pressure indication. If
a wet shutoff is the right answer, why let the pump go a little dry?
　
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