Inert your fuel tanks – soon (ish)

[African Tech Rep]

Could be another nail in the coffin of some old ones – planes that is

FOR IMMEDIATE RELEASE


AOC 39-05 November 14, 2005
Contact: Alison Duquette
Phone: 202-267-3883 FAA Proposes Rule to Reduce Fuel Tank Explosion Risk WASHINGTON, D.C. — The U.S.
Department of Transportation's Federal
Aviation Administration (FAA) today
proposed a rule that would make
aviation significantly safer by
requiring more than 3,200 existing and
certain new large passenger jets to
reduce flammability levels of fuel
tank vapors.
<P>
"Safer fuel tanks on aircraft will
help prevent the possibility of future
explosions and the tragic loss of
lives," U.S. Transportation Secretary
Norman Y. Mineta said.
<P>
The Notice of Proposed Rulemaking
(NPRM) would require aircraft
operators to reduce the flammability
levels of fuel tank vapors on the
ground and in the air to remove the
likelihood of a potential explosion
from an ignition source. The proposed
rule is designed to reduce the
likelihood of a repeat of the three
fuel tank explosions over the past 14
years, including the 1996 TWA 800
accident, that together have resulted
in 346 fatalities.
<P>
"This proposed rule is the next step
to close the book on fuel tank
explosions," said FAA Administrator
Marion C. Blakey. "We're proposing to
increase the level of aircraft safety
by reducing the potentially explosive
ingredient of flammable fuel vapors."
<P>
Blakey added that today's proposed
rule builds on more than 70 directives
during the past nine years designed to
eliminate ignition sources and to
change fuel tank design and
maintenance. Previous directives have
addressed issues such as pump
manufacturing discrepancies, wire
chafing, and protection of the Fuel
Quantity Indication System.
<P>
One possible solution allowed by the
rule is fuel tank inerting. In May
2002, FAA engineers unveiled a
prototype to replace oxygen in the
fuel tank with inert gas, which
prevents the potential ignition of
flammable vapors. Boeing has since
developed its own system, which will
be installed on new airplanes. The FAA
will consider data supporting other
means of compliance.
<P>
The FAA's proposal would apply to new
large airplane designs. In addition,
since the FAA would require a retrofit
of more than 3,200 Airbus and Boeing
aircraft with center wing fuel tanks
over seven years, Boeing 737, Boeing
747, and Airbus A320 models would be
retrofitted first. The preliminary
estimate for the total cost for the
U.S. fleet is approximately $808
million over 49 years, including $313
million for retrofitting the existing
fleet. The following is the projected
U.S. aircraft fleet that would be
retrofitted:
<P>
Airbus Models Number of
Aircraft<BR>
Airbus A320 906<BR>


Airbus A330 44<BR>

<P>
Boeing Models Number of
Aircraft<BR>
Boeing 737
1,149<BR>
Boeing 747 93<BR>

Boeing 757 581<BR>

Boeing 767 347<BR>

Boeing 777 157<BR>

<P>
The NPRM is on display today at the
<I>Federal Register.</I> It is
available on the Internet at
http://dms/dot.gov, docket FAA 2005-
22997 and on the FAA's website at
www.faa.gov/regulations_policies/rulema
king/recently_published/. The 120-day
public comment period closes on March
20, 2006.

[PaperTiger]

...requiring more than 3,200 existing and
certain new large passenger jets to
reduce flammability...Hmmm. Only certain new ones. Wonder who wants an exemption :suspect:

[African Tech Rep]

The good thing is Concorde will be Exempt. :confused:

It’s interesting they seem to leaning towards Pax planes only – the Cost / Benefit seeming to show it don’t matter so much if a cargo one blows up :hmm:

[Hunter58]

Sure

for most aviation authority the crews are not alive, unlike passengers...

[Shore Guy]

Cargo Jets exempt......

So much for the much touted "One level of Safety"

[African Tech Rep]

A couple of intresting extracts from the full NPRM

Some airplane models have center tanks with a fleet average flammability exposure level that does not exceed 7 percent, including to the best of our information the Lockheed L-
101 1, and Boeing MD-1 I, DCIO, MD80, and Boeing Model 727, and Fokker F28 MKIOO. At this time we do not believe that these airplanes would need FRM or IMM for their center tanks, unless the certificate holder has also installed an auxiliary fuel tank that is found to be
affected.'

The proposal does not extend to airplanes used in all-cargo operations. Our analysis of the costs of extending the proposal to include these airplanes does not appear to be justified by the associated benefits. The potential loss of life in a single accident is much smaller on allcargo planes of the size contemplated by today's proposal than on comparably sized passenger planes. The undiscounted cargo airplane costs would be about $261 million, with a present value of $1 10 million, while the benefits would be less than $1 million. However, the FAA does believe there is a risk to all-cargo airplanes because they share the same design features as at-risk passenger airplanes. We typically do not base our certification standards for transport category airplanes on use. Rather, our general philosophy is to address the performance characteristics of these airplanes because we believe all occupants should be protected against those designs that present a risk of serious injury or death

Cargo jets are NOT exempt YET - it is after all a NPRM - so if enough noise is made cargo could be in the Final - but not sure many cargo companies would thank you.

BTW - OCR in Adobe 7 is s**t hot

[Earl]

Someone correct me if I am wrong, but I read the likely cause of the TWA 800 accident was the ground power unit exhaust was blowing on the center wing tanks heating the fuel up even further to possible critical levels.
Now how many times have we done a exterior preflight on this aircraft and never found the GPU in this area?
Maybe I am missing something here?
I dont think the boost pump problem was the culprit.
Yes nitrogen will displace the oxygen levels to where an explosion is less likely
but they never found the original cause of this accident.
I read elsewhere as to the Department of transportation forcing this issue.