65FR34800 Freightliner Corporation; Receipt of Application for Decision of Inconsequential Noncompliance
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Posting-number: Volume 65, Issue 105, Page 34800
[Federal Register: May 31, 2000 (Volume 65, Number 105)]
[Notices]
[Page 34800-34801]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr31my00-115]
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DEPARTMENT OF TRANSPORTATION
National Highway Traffic Safety Administration
[Docket No. NHTSA-2000-7361; Notice 1]
Freightliner Corporation; Receipt of Application for Decision of
Inconsequential Noncompliance
Freightliner Corporation (Freightliner) of Portland, Oregon, has
determined that some of its vehicles fail to meet the brake release
time requirements of paragraph S5.3.4.1(b) of Federal Motor Vehicle
Safety Standard (FMVSS) No. 121, Air Brake Systems. On May 8, 1997,
Freightliner filed a noncompliance information report pursuant to 49
CFR Part 573.5. In that report, Freightliner indicated that it would
file a petition for inconsequential noncompliance at a future date.
Freightliner states that a Petition for Inconsequential Noncompliance
dated October 10, 1997 was submitted to the agency but we have no
record of it. Subsequently, on February 29, 2000, Freightliner
resubmitted its Petition dated October 10, 1997.
This notice of receipt of the application is published under 49
U.S.C. 30118 and 30120, and does not represent an agency decision or
other exercise of judgement concerning the merits of the application.
Under the requirements of S5.3.4.1(a) of FMVSS No. 121, each truck
equipped with air brakes is required to have a pressure reduction from
95 psi to 5 psi, measured at each brake chamber of the truck, in not
more than 0.55 second from the initial movement (release) of the
service brake control. In addition, S5.3.4.1(b) requires that a truck
which is equipped to tow another air-braked vehicle is required to have
a pressure reduction from the initial test pressure equivalent to 95
psi in the truck's brake chambers, to 5 psi in not more than 0.75
second, measured in a 50-cubic-inch test reservoir attached to the
control line coupling, upon initial movement (release) of the service
brake control. Thus the pressure in the test reservoir is required to
drop from approximately 95 psi to 5 psi in not more than 0.75 second
upon release of the service brake control.
Number of Non-Complying Trucks
From January 1994 through April 1996, Freightliner produced
approximately 3,145 Model FLD trucks that may not have had a quick-
release valve installed at the control line coupling and therefore may
not meet the release timing requirements in FMVSS No. 121. Data on the
number of vehicles of the 3,145 affected truck population that were
built without the quick release valve are as follows. According to
Freightliner's noncompliance information report, a field inspection of
34 subject vehicles indicated that 5.9 percent (two trucks) did not
have the quick release valves. According to Freightliner's petition for
inconsequential noncompliance, an inspection (of an unspecified number)
of trucks at the St. Thomas Manufacturing Plant where these vehicles
were manufactured indicated that 69 percent were manufactured without
the quick release valve. Freightliner also said in its petition that a
field inspection of 38 subject trucks indicated that 9 percent did not
have the quick release valve installed.
We telephoned Mr. Tony Moore of Freightliner's engineering
department and Mr. Larry Winslow of Freightliner's compliance
department on April 4, 2000, to clarify the numbers of non-compliant
vehicles and two other subjects that are discussed below. The field
inspection of 38 trucks indicated in the petition included the 34
trucks identified in the noncompliance information report. When asked
about the number of vehicles inspected at the St. Thomas plant,
Freightliner indicated that it has documentation showing that 303
trucks were inspected, and 70 trucks or 23 percent did not have quick
release valves installed. Freightliner could not locate documentation
regarding how the 69 percent number in the petition was derived and
believes that this number is incorrect per the documentation it now
has.
Brake Release Times of Non-Complying Trucks
FMVSS No. 121, paragraph S5.3.4.1(b), requires that the release
timing measured in the test reservoir from initial pressure to 5 psi
shall be 0.75 second. In its petition, Freightliner states that it
conducted a test program to predict the actual release timing of the
subject vehicles. The results are as indicated in the table below:
------------------------------------------------------------------------
Vehicle Percent of
[Predicted] release timing (seconds) population population
------------------------------------------------------------------------
0.76-0.80.................................... 773 24.5
0.81-0.85.................................... 1759 55.9
0.86-0.90.................................... 602 19.1
0.91-0.95.................................... 1 0.03
0.96-1.00.................................... 10 0.3
over 1.00.................................... 0 0
------------------------------------------------------------------------
In the April 4, 2000 telephone conversation, Freightliner indicated
that this prediction of release timing is based upon the length of the
air tubing from the treadle valve to the trailer service air line glad
hand coupling. The overall length of the air tubing varies with tractor
wheelbase and the resulting vehicle population numbers in the table
were derived on this basis. Without the quick release valve, the air is
released through the treadle valve. As indicated in Freightliner's
petition, the installation of the quick release valve releases the air
at the tractor end of the trailer service air line.
Freightliner Rationale for Inconsequentiality to Safety
Freightliner does not believe that tractor glad hand timing between
0.75 and 1.00 second poses any risk or compromises highway safety. It
states that brake application pressures at a highway speed of 55 mph
rarely exceed 20 psi, and that when comparing the release timing from
20 psi on vehicles that would have 0.90 and 0.75 second release timing
when tested according to FMVSS No. 121, the actual time differential
drops to less than 0.10 second. In the April 4, 2000, telephone
conversation, Freightliner clarified that the 0.10 second timing is the
time for the pressure to be reduced at the glad hand coupling from 20
psi to 5 psi on trucks with no quick release valve installed.
Freightliner also indicated that it did not do a comparable analysis of
release timing from 20 psi with the quick release valve installed.
Freightliner believes that glad hand timing requirements were
established primarily for the purpose of improving the application
timing balance of combination vehicles, not the release timing.
Freightliner cites the summary in Docket No. 85-07, Notice 3, as
follows:
The purpose of the glad hand timing requirements is to ensure
that the air delivery from towing vehicles to towed vehicles is fast
enough to apply the brakes of all vehicles in the combination at
approximately the same time, thereby avoiding a reduction in the
combination stability (e.g., trailer bumping) caused by a slow glad
hand.
Freightliner states that release timing is not mentioned, and that
some
[[Page 34801]]
commenters in the same docket questioned NHTSA's research in justifying
the proposed release timing requirement. Freightliner indicates that
one commenter stated that it is difficult to determine the effect of
trailer release timing and tractor/trailer release differentials on
compatibility and suggested testing indicated 0.90 second is
sufficient. Freightliner also indicates that another commenter argued
that a 1.00 second release timing would be more practical and
accomplish the objective of the proposal, and that NHTSA stated that:
A short glad hand release time is not as important for safety
and, in fact, it is not desirable to have the glad hand release
before the tractor brakes.
Freightliner believes that requiring the rearmost vehicle to
release last tends to ``stretch'' out the unit (vehicle combination)
and make it more stable, and that slower than the required release time
may actually help overall stability.
Freightliner summarizes its petition by stating that an estimated
280 to 2170 tractors were manufactured without quick release valves
such that the glad hand release timing may be slightly higher than the
0.75 second specified in FMVSS No. 121, and that nearly all (99.6
percent) do not exceed 0.90 second. Freightliner believes that this
timing difference of 0.0 to 0.15 second has no discernable or
measurable effect on braking performance and thus no detrimental effect
on highway safety. Therefore, it requests that we grant its petition to
exempt it from the notification and remedy requirements of the Motor
Vehicle Safety Act.
Comments and Docket Submissions
Interested persons are invited to submit written data, views, and
arguments on Freightliner's petition for inconsequential noncompliance
described above. Comments should refer to the Docket Number and be
submitted to Docket Management at the address given above under
ADDRESSES.
All comments received before the close of business on the closing
date indicated below will be considered. The application, supporting
materials, and comments also will be filed in the docket. Comments
received after the closing date will also be filed and considered to
the extent possible. When the petition is granted or denied, the notice
will be published in the Federal Register pursuant to the authority
indicated below.
Comment closing date: June 30, 2000.
(15 U.S.C. 1417; delegation of authority at 49 CFR 1.50 and 49 CFR
501.8)
Issued on: May 23, 2000.
Stephen R. Kratzke,
Associate Administrator for Safety Performance Standards.
[FR Doc. 00-13536 Filed 5-30-00; 8:45 am]
BILLING CODE 4910-59-P