1. Is Boeing aware that the mfg. of the ship's wiring on TWA 800
max at 60,000 hrs? (accident a/c had 93,303 hrs) and that BMS13-42-B
banned by the military due to premature aging found in laboratory
affirmed by the IEEE as failing after 2,000 hrs? Was Boeing concerned
they themselves discovered this failure after only 6,000 hrs in
2. Who is responsible for the wiring approval/selection process,
3. Will BMS 13-13 PVC/nylon pass the FAA's 60 degree flame test?
The FAA says
When exactly did Boeing first have to meet the 60 degree flame test
required by FAR 25 for the certification approvals on their various
that used this type wire (DC-9s, 727s, 737s)?
4. Was Boeing aware that NASA has a restriction on the flammability
characteristics of BMS 13-48 in a 30% oxygen enriched area"
5. Was Boeing aware that Lockheed demonstrated arc-tracking characteristics
of kapton wire(BMS 13-51) in 1972?
What means does Boeing use to guesstimate or project the service
6. If ,as Boeing admitted in 1997 that no MSG-3 testing has ever
been done on
the wiring, (to see what-if this failed), how can it be assumed/assured
the basic idea of redundancy of wiring systems helps rather than
the proximity/lack of separation/convergence of bundles issues all
against the idea of maintaining circuit integrity when considering
dramatic failure mode of BMS13-51)?
7. How do Boeing's wiring diagrams compare to real-world installation
practices regard to wire separation requirements.
8. What formula is used by Boeing in designing a wire bundle in
ambient temp., wire size, number of conductors, currents/voltages
EMI& HIRF sensitivities?
9. Is Boeing aware that the wires used in BMS13-42 C&D (stilan
polyarylene) are banned by NASA and the Dept. of Defense?
10. What inspection criteria is given to the operators to detect
particular failure modes with the various wire insulations?
11. Is Boeing aware of the 1992 declaration by the NTSB on not re-energizing
kapton insulated wires?
12. Why was BMS 13-48 removed from pressurized areas in 1988?
13. Would mixing BMS13-48 and BMS 13-51 in the same wire bundle
be cause for
alarm based on the differences in abrasion resistance and mechanical
strengths at rated temperatures?
14. Is Boeing aware that BMS 13-48 has a 97% smoke obscurity rating
by the FAA/
15. Would there be any concern over the need to maintain overall
temperature ratings by mixing various wire insulations, if in fact
16. Has Boeing done any vibration testing on mixing wire types at
temperatures? If so, at what temperatures?
17. Is Boeing going to issue any advisory circulars to alert operators
kapton wired a/c about the danger of re-energizing this type of
18. What kind of CAS program is in place to identify any common-thread
occurrences with the various a/c types and their specific wire types?
747 -400/MD11 have had numerous ADs on the same kapton wire failures,
DC-10/747s both had similar problems with radial cracking of poly-x).
19. Is Boeing aware that Grumman banned BMS13-48 wire from manned
applications due to the toxicity of that material? Or that NASA
concerns of BMS 13-48 exploding in an oxygen enriched area(i.e.
20. How does Boeing discern the difference in wiring burned in an
fire versus an electrically induced burned wire when they participate
Designated Engineering Representatives for the NTSB?
21. If Boeing was aware of the longitudinal splitting problems of
teflon since 1971, why didn't they inspect/replace that type wire
their center fuel tanks?
22.How many areas of the a/c had to have teflon sleeves placed over
cracked poly-x wires on the 747? How many ADs were issued on those
23. What percentage of the wiring gets replaced on an in the course
lifetime? What percentage of the a/c's wiring is considered inaccessible
Why does Boeing still use BMS13-48 still in their large transports
those aforementioned short-comings are known, especially in calling
as replacement wires in the 747 wing tanks as recently as 1997-1998?
24. Why does only the smaller transports 737,757 use BMS13-60 and
why not use
this improved wire type across the board?
25. Based on all these references to the various wire types and
associated failure modes, would it be safe to assume that insulation
matters in regard to smoke-checklist instructions (not re-energizing
BMS 13-48), flammability of certain wire types (BMS13-13, &
projecting/providing for the shortened service life of poly-x, BMS
and even fire-fighting concerns since some wire types (PVC/nylon)
hydrochloric acid when hit with water when burning (BMS 13-13)?
26. Is Boeing aware of the susceptibility of BMS13-42D to hydraulic
deicing fluid and the resultant crazing (or internal fracturing)
with the naked eye?
27. Has Boeing either considered or tested for the effect that electrical
anomalies would have on the 737s rudder problem? Boeing stated 12/97
wire failures were never tested for in their MSG-3 program (i.e.
28. What would happen if the autopilot on a 737 shorted out, would
any way of recovering from the a/c's last commands that would be
unless the yoke is broken by the pilot? Would throttling-up work
if the flight surfaces were still locked-in via the short?
What is the difference and what would be the effects of momentary
metal contact between conductors or conductor and structure having
insufficient time to build up heat and thermally trip circuit-breakers
degraded wire insulation versus arc-tracking of conductors?
29. Is Boeing aware that BMS-13-48 will wet arc-track?
30. Does Boeing consider, like the FAA does, that wire is wire?