[Federal Register Volume 59, Number 33 (Thursday, February 17, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-3581]


[[Page Unknown]]

[Federal Register: February 17, 1994]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 93-NM-209-AD; Amendment 39-8814; AD 94-03-07]

 

Airworthiness Directives; Boeing Model 767 Series Airplanes 
Equipped With Carbon Brakes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; correction.

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SUMMARY: This document corrects a typographical error in an existing 
airworthiness directive (AD) that is applicable to certain Boeing Model 
767 series airplanes. That AD currently requires inspections of the 
brake rod inner cylinder bolts on the main landing gear (MLG) wheels 
and brakes; inspections of certain MLG bushings; installation of 
retainer plates at each MLG brake disconnect; inspection and 
modification of the brake rod pin assembly at each MLG wheel; repair or 
replacement of discrepant parts; and revision of the Airplane Flight 
Manual (AFM), as necessary. This action corrects a column heading in a 
table that appeared in the rule. This action is necessary to ensure 
that affected operators are aware of the correct accellerate-stop 
distances to observe when complying with certain requirements of the 
rule.

DATES: Effective February 18, 1994. -
    The incorporation by reference of certain publications listed in 
the regulations was previously approved by the Director of the Federal 
Register as of February 18, 1994 (59 FR 5074, February 3, 1994).

ADDRESSES: The service information referenced in this AD may be 
obtained from Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, 
Washington 98124-2207. This information may be examined at the Federal 
Aviation Administration (FAA), Transport Airplane Directorate, Rules 
Docket, 1601 Lind Avenue, SW., Renton, Washington; or at the Office of 
the Federal Register, 800 North Capitol Street, NW., suite 700, 
Washington, DC.

FOR FURTHER INFORMATION CONTACT: Kristin Larson, Aerospace Engineer, 
Systems and Equipment Branch, ANM-130S, FAA, Transport Airplane 
Directorate, Seattle Aircraft Certification Office, 1601 Lind Avenue 
SW., Renton, Washington 98055-4056; telephone (206) 227-1760; fax (206) 
227-1181.

SUPPLEMENTARY INFORMATION: On January 27, 1994, the FAA issued AD 94-
03-07, Amendment 39-8814 (59 FR 5074, February 3, 1994), which is 
applicable to Boeing Model 767 series airplanes equipped with carbon 
brakes. That AD requires inspections of the brake rod inner cylinder 
bolts on the main landing gear (MLG) wheels and brakes; inspections of 
certain MLG bushings; installation of retainer plates at each MLG brake 
disconnect; inspection and modification of the brake rod pin assembly 
at each MLG wheel; repair or replacement of discrepant parts; and 
revision of the FAA-approved Airplane Flight Manual (AFM), as 
necessary. That action was prompted by numerous reports of brake 
failure during landing and during a low energy rejected takeoff. The 
actions required by that AD are intended to prevent failure of two or 
more MLG brakes, which could adversely affect the stopping performance 
of the airplane. -
    Recently, the FAA has become aware of the fact that the version of 
this AD that was published in the Federal Register contained a 
typographical error in paragraph (f). That paragraph requires that the 
AFM be revised to include information concerning two-brake-deactivated 
performance decrements that must be observed until certain inspections 
and installation actions required by paragraphs (a) through (b)(3) of 
the AD have been accomplished. -
    That AFM revision contains three ``options'' with which affected 
operators may comply. ``Option 3'' of this AFM revision information 
contains a table specifying ``Corrected Accelerate Stop Distances'' 
(Section 4.3 of the AFM) that operators who elect to comply with 
``Option 3'' are to observe when calculating the maximum allowable 
takeoff weight of the airplane. In the portion of the AD published in 
the Federal Register, the headings of two columns [``Corrected Accel-
Stop Distance (feet)'' and ``Adjusted Corrected Accel-Stop Distance 
(feet)''] in this table were inadvertently transposed. With such a 
transposition, the material appearing in the respective columns could 
be misleading to operators attempting to comply with this portion of 
the rule. -
    The FAA has determined that it is appropriate to take action to 
correct AD 94-03-07 to correctly label the columns of material 
appearing in the table included under ``Option 3'' of paragraph (f). -
    Action is taken herein to correct the error and to correctly add 
the AD as an amendment to Sec. 39.13 of the Federal Aviation 
Regulations (FAR). The effective date of the rule remains February 18, 
1994. -
    The final rule is being reprinted in its entirety for the 
convenience of affected operators. -
    Since this action only corrects columnar headings in a table 
related to an optional method of compliance with a rule, it has no 
adverse economic impact and imposes no additional burden on any person. 
Therefore, notice and public procedures hereon are unnecessary.

List of Subjects in 14 CFR Part 39 -

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

Adoption of the Correction -

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration amends 14 CFR part 
39 of the Federal Aviation Regulations as follows:

PART 39--AIRWORTHINESS DIRECTIVES -

    1. The authority citation for part 39 continues to read as follows:

    Authority: 49 U.S.C. App. 1354(a), 1421 and 1423; 49 U.S.C. 
106(g); and 14 CFR 11.89.


Sec. 39.13  [Amended] -

    2. Section 39.13 is amended by correctly adding the following 
airworthiness directive (AD):

94-03-07 Boeing: Amendment 39-8814. Docket 93-NM-209-AD.

    -Applicability: Model 767 series airplanes equipped with carbon 
brakes, certificated in any category. -
    Compliance: Required as indicated, unless accomplished 
previously. -
    To prevent failure of two or more MLG brakes, which could 
adversely affect the stopping performance of the airplane, 
accomplish the following: -
    (a) Except as provided in paragraph (f) of this AD, within 60 
days after the effective date of this AD, accomplish paragraphs 
(a)(1) and (a)(2) of this AD in accordance with Boeing Service 
Bulletin 767-32A0116, Revision 1, dated January 13, 1994: -
    (1) Perform a surface temper etch inspection and a fluorescent 
magnetic particle inspection to detect cracks or thermal damage of 
the brake rod inner cylinder bolts on the main landing gear (MLG) 
wheels and brakes in accordance with the service bulletin. As a 
result of these inspections, accomplish either paragraph (a)(1)(i) 
or (a)(1)(ii) of this AD, as applicable: -
    (i) If cracking or thermal damage is found on any bolt: Prior to 
further flight, replace the existing bolt with a new or serviceable 
bolt in accordance with the service bulletin. Repeat the inspections 
thereafter at intervals not to exceed 800 flight cycles.
    (ii) If cracking or thermal damage is not found on any bolt: 
Apply finish and reinstall the bolt in accordance with the service 
bulletin. Repeat the inspections thereafter at intervals not to 
exceed 800 flight cycles. -
    (2) Perform a visual inspection to detect cracking of the inner 
cylinder fork lug bushings and the brake rod bushings at the inner 
cylinder fork lug end in accordance with the service bulletin. 
Repeat that inspection thereafter at intervals not to exceed 800 
flight cycles. -
    (b) For airplanes having line positions 132 through 518, 
inclusive: Except as provided in paragraph (f) of this AD, within 60 
days after the effective date of this AD, accomplish paragraphs 
(b)(1), (b)(2), and (b)(3), as follows: -
    (1) Install the retainer plates at each MLG brake disconnect; 
and adjust the torque of the ``B''-nut on the hydraulic line 
connection to the disconnect fitting; in accordance with Boeing 
Alert Service Bulletin 767-32A0125, dated November 11, 1993. -
    (2) Remove the cross bolt from the brake housing and brake rod 
pin assembly at each MLG wheel; remove the brake rod pin assembly; 
perform a visual inspection of the brake rod pin assembly to detect 
cracks, bronze transfer, corrosion, chrome discoloration, and areas 
of missing chrome plate; prior to further flight, replace any 
damaged brake rod pin assembly with a new or serviceable assembly; 
modify the brake rod pin assembly; install the modified brake rod 
pin into the brake housing and brake rod; and install a new brake 
attach pin retainer configuration; in accordance with Boeing Service 
Bulletin 767-32A0126, Revision 1, dated January 13, 1994. -
    (3) Perform a one-time visual inspection to detect cracking, 
deformation, and/or a missing piece in the bushings in the brake 
housing, and the bushings in the end of the brake rod, in accordance 
with Boeing Service Bulletin 767-32A0126, Revision 1, dated January 
13, 1994. -
    (c) For any bushing that is found broken and/or any bushing that 
is found having a piece missing during the inspection(s) required by 
paragraphs (a)(2) and/or (b)(3) of this AD, accomplish the 
requirements of either paragraph (c)(1) or (c)(2), as follows: -
    (1) Within 10 flight cycles after detection, repair or replace 
the bushing in accordance with the appropriate service bulletin. No 
performance decrements are required within the first 10 flight 
cycles since detection. Or -
    (2) If the affected bushing has not been replaced within 10 
flight cycles after detection, observe one-brake-deactivated 
performance decrements in accordance with the FAA-approved Airplane 
Flight Manual (AFM) until replacement of the affected bushing is 
accomplished. Operation must be performed with all brakes and the 
antiskid system fully functional, while operating with one-brake-
deactivated performance decrements for broken bushings and/or a 
bushing with a missing piece. -
    (d) For any bushing that is found to be cracked or deformed 
during the inspection(s) required by paragraphs (a)(2) and/or (b)(3) 
of this AD, accomplish the requirements of either paragraph (d)(1) 
or (d)(2), as follows: -
    (1) Within 100 flight cycles since detection, repair or replace 
the bushing in accordance with the appropriate service bulletin. No 
performance decrements are required within the first 100 flight 
cycles since detection. Or -
    (2) If the affected bushing(s) has not been replaced within 100 
flight cycles since detection, observe one-brake-deactivated 
performance decrements in accordance with the FAA-approved AFM until 
replacement of the affected bushing is accomplished. Operation must 
be performed with all brakes and the antiskid system fully 
functional, while operating with one-brake-deactivated performance 
decrements for cracked bushings. -
    (e) Operators may operate beyond 60 days after the effective 
date of this AD with one-brake-deactivated performance decrements 
for cracked or broken bushings, provided that the actions required 
by paragraphs (a) through (b)(3) of this AD have been accomplished. 
-
    (f) Revise the Limitations and Flight Performance sections of 
the FAA-approved AFM (or computer generated takeoff weight tables) 
to include the following information. (This may be accomplished by 
inserting a copy of this AD in the AFM.) If the actions required by 
paragraphs (a) through (b)(3) of this AD have not been accomplished 
within 60 days after the effective date of this AD, the following 
two-brake-deactivated performance decrements must be observed until 
the actions required by paragraphs (a) through (b)(3) of this AD 
have been accomplished. The following adjustments reflect takeoff 
and landing performance, assuming failure of two brakes. Operation 
must be performed with all brakes operative and the anti-skid system 
operative.

Option 1

    (1) Subtract 70,000 LB ( 31,750 KG) from the takeoff limited 
weight (the most limiting (lowest) of maximum certified, obstacle 
clearance, tire speed, brake energy, climb, or field length limited 
weight). No adjustment to the takeoff speeds for the resulting 
weight is required.
    (2) Landing Field Length--Section 4.13 of the Airplane Flight 
Manual: Multiply `all brakes operative' FAR landing field length by 
a factor of 1.20.
    (3) Maximum Quick Turnaround Weight--Section 4.13 of the 
Airplane Flight Manual: No change from the `all brakes operative' 
value.

Option 2

    (1) Field Length Limited Weight--Section 4.4 of the Airplane 
Flight Manual: Reduce the `all brakes operative' field length 
limited weight by 10,500 LB (4,750 KG). The maximum allowable 
takeoff weight is the most limiting (lowest) of maximum certified, 
climb, obstacle clearance, tire speed, or this adjusted field length 
limited weight.
    (2) Reference V1(mcg) Limited Accelerate-Stop Distance--
Section 4.8 of the Airplane Flight Manual: Increase the reference 
V1(mcg) limited accelerate-stop distance by 1000 FT.
    (3) Takeoff Decision Speed, V1--Section 4.7 of the Airplane 
Flight Manual: Reduce V1 by the following:

Weights below 330,000 LB (150,000 KG): Subtract 4 knots ---
Weights at or above 330,000 LB (150,000 KG): Subtract 3 knots

    If the resulting V1 is less than V1(mcg), takeoff is 
permitted with V1 set equal to V1(mcg) provided the 
corrected accelerate-stop distance available exceeds the adjusted 
reference V1(mcg) limited accelerate-stop distance from Step 2.
    (4) Brake Energy Limits--Section 4.7 of the Airplane Flight 
Manual: Reduce the maximum brake energy speed allowed with all 
brakes operative by 30 knots. Verify the scheduled V1 is less 
than the reduced VMBE. If not, then takeoff weight must be 
reduced.
    (5) Landing Field Length--Section 4.13 of the Airplane Flight 
Manual: Multiply `all brakes operative' FAR landing field length by 
a factor of 1.20.
    (6) Maximum Quick Turnaround Weight--Section 4.13 of the 
Airplane Flight Manual: No change from the `all brakes operative' 
value.

Option 3

    Once the following adjustments to corrected accelerate-stop 
distance and VMBE are determined, the takeoff weights should be 
calculated in the normal fashion (using these adjusted data) to 
determine the maximum allowable takeoff weight.
    (1) Corrected Accelerate Stop Distance--Section 4.3 of the 
Airplane Flight Manual: Use the following table to adjust the 
corrected accelerate-stop distance. 

------------------------------------------------------------------------
                                                                Adjusted
                                       Adjusted     Corrected  corrected
  Corrected accel-stop distance    corrected accel-   accel-     accel- 
              (feet)                stop distance      stop       stop  
                                   (feet)---------   distance   distance
                                                      (feet)     (feet) 
------------------------------------------------------------------------
4000.............................          3420        13,000     11,552
5000.............................          4312        14,000     12,470
6000.............................          5206        15,000     13,391
7000.............................          6104        16,000     14,315
8000.............................          7005        17,000     15,241
9000.............................          7908        18,000     16,171
10,000...........................          8815        19,000     17,104
11,000...........................          9724        20,000     18,039
12,000...........................        10,637     .........  .........
------------------------------------------------------------------------

    Linearly interpolate for accelerate-stop distance values between 
those shown.
    (2) Reference V1(mcg) Limited Accelerate-Stop Distance--
Section 4.8 of the Airplane Flight Manual: Increase the reference 
V1(mcg) limited accelerate-stop distance by 500 FT.
    If V1 is less than V1(mcg), takeoff is permitted with 
V1 set equal to V1(mcg) provided the corrected accelerate-
stop distance available exceeds this adjusted reference V1(mcg) 
limited accelerate-stop distance.
    (3) Brake Energy Limits--Section 4.7 of the Airplane Flight 
Manual: Use the following table to adjust the maximum brake energy 
speed allowed with all brakes operative after correcting for runway 
slope and wind. 

------------------------------------------------------------------------
                                      Adjusted    All brake             
      All brake op VMBE--KIAS        VMBE--KIAS   op VMBE--    Adjusted 
                                                    KIAS-     VMBE--KIAS
------------------------------------------------------------------------
100................................       84.2         170        141.4 
110................................       92.4         180        149.6 
120................................      100.6         190        157.8 
130................................      108.7         200        166.0 
140................................      116.9         210        174.2 
150................................      125.1         220        182.3 
160................................      133.3   ...........  ..........
------------------------------------------------------------------------

    Linearly interpolate for VMBE values between those shown.
    (4) Landing Field Length--Section 4.13 of the Airplane Flight 
Manual: Multiply `all brakes operative' FAR landing field length by 
a factor of 1.20.
    (5) Maximum Quick Turnaround Weight--Section 4.13 of the 
Airplane Flight Manual: No change from the `all brakes operative' 
value.''
    (g) An alternative method of compliance or adjustment of the 
compliance time that provides an acceptable level of safety may be 
used if approved by the Manager, Seattle Aircraft Certification 
Office (ACO), FAA, Transport Airplane Directorate. Operators shall 
submit their requests through an appropriate FAA Principal 
Maintenance Inspector, who may add comments and then send it to the 
Manager, Seattle ACO.

    Note: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Seattle ACO.

    (h) Special flight permits may be issued in accordance with FAR 
21.197 and 21.199 to operate the airplane to a location where the 
requirements of this AD can be accomplished.
    (i) The actions shall be done in accordance with Boeing Service 
Bulletin 767-32A0116, Revision 1, dated January 13, 1994; Boeing 
Alert Service Bulletin 767-32A0125, dated November 11, 1993; and 
Boeing Service Bulletin 767-32A0126, Revision 1, dated January 13, 
1994. This incorporation by reference was approved by the Director 
of the Federal Register, in accordance with 5 U.S.C. 552(a) and 1 
CFR part 51, as of February 18, 1994 (59 FR 5074, February 3, 1994). 
Copies may be obtained from Boeing Commercial Airplane Group, P.O. 
Box 3707, Seattle, Washington 98124-2207. Copies may be inspected at 
the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., 
Renton, Washington; or at the Office of the Federal Register, 800 
North Capitol Street, NW., suite 700, Washington, DC.
    (j) This amendment becomes effective on February 18, 1994.

    Issued in Renton, Washington, on February 10, 1994.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 94-3581 Filed 2-16-94; 8:45 am]
BILLING CODE 4910-13-U