[Federal Register Volume 59, Number 23 (Thursday, February 3, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-2336]


[[Page Unknown]]

[Federal Register: February 3, 1994]


=======================================================================
-----------------------------------------------------------------------

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; request for comments.

-----------------------------------------------------------------------

SUMMARY: This amendment adopts a new airworthiness directive (AD) that 
is applicable to certain Boeing Model 767 series airplanes. This action 
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 amendment is prompted 
by numerous reports of brake failure during landing and during a low 
energy rejected takeoff. The actions specified in this AD are intended 
to prevent failure of two or more MLG brakes, which could adversely 
affect the stopping performance of the airplane.

DATES: Effective February 18, 1994.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of February 18, 1994.
    Comments for inclusion in the Rules Docket must be received on or 
before April 4, 1994.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 93-NM-209-AD, 1601 Lind Avenue, SW., 
Renton, Washington 98055-4056.
    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 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.

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: The FAA has received reports from Boeing 
that certain Model 767 series airplanes, equipped with carbon brakes, 
have experienced vibratory conditions, which resulted in damage or 
failure of the brake torque rod cross bolts and pins. Recently, one 
operator experienced a two-brake failure on a low energy rejected 
takeoff, whereas previously, there had been reports of two-brake 
failures occurring only during landings. To date, there have been 13 
reported incidents of one-brake failure and 5 incidents of a two-brake 
failure, all due to the vibratory phenomenon. This type of failure 
could result in the loss of one or two brakes (out of eight total 
brakes), depending upon the location of the failure. The possibility 
exists that more than one brake-couple pair could experience 
simultaneous failure of the cross bolts or pins, which could result in 
the loss of more than two brakes.
    Boeing has advised the FAA that heat damage resulting from high 
vibrational loads could lead to fracture of the brake rod inner 
cylinder bolts. If this should occur, the adjacent brake rods would 
disconnect from the inner cylinder, causing the brakes not to operate 
at two MLG wheels. As a result, secondary damage to the hydraulic lines 
and damage to wiring and the airframe could occur.
    Boeing has also advised the FAA that vibrations during braking can 
lead to separation of the brake disconnect. Separation of brake hoses 
from the brakes would increase braking distances, which is of greatest 
concern if this should happen during a rejected takeoff.
    Additionally, Boeing has advised the FAA that the development of a 
fracture in a cross bolt in the brake rod pin assembly could cause the 
brake not to operate at that MLG wheel. The brake rod could separate 
from the brake housing, permitting the brake housing to turn on the 
axle. Under such conditions, while the wheel turns and brake pressure 
is applied, rotation of the brake housing would cut the hydraulic line 
and electrical wires attached to the brake.
    These conditions, if not corrected, could adversely affect the 
stopping performance of the airplane.
    The FAA has reviewed and approved Boeing Service Bulletin 767-
32A0116, Revision 1, dated January 13, 1994, that describes procedures 
for repetitive surface temper etch inspections and fluorescent magnetic 
particle inspections to detect cracks or thermal damage of the existing 
brake rod inner cylinder bolts on the MLG wheels and brakes, and 
replacement of cracked or damaged bolts with new or serviceable bolts. 
The service bulletin also describes procedures for performing 
repetitive visual inspections to detect cracking of the inner cylinder 
fork lug bushings, and the brake rod bushings at the inner cylinder 
fork lug end, and repair of cracked bushings. Accomplishment of the 
repetitive inspections, and replacement or repair as necessary, will 
help prevent the possibility of a fracture developing in the brake rod 
inner cylinder bolts. (The service bulletin limits the effectivity to 
Model 767 series airplanes equipped with carbon brakes.)
    The FAA has also reviewed and approved Boeing Alert Service 
Bulletin 767-32A0125, dated November 11, 1993, that describes 
procedures for installation of retainer plates at each MLG brake 
disconnect. The alert service bulletin also describes procedures for 
adjustment of the torque of the ``B''-nut on the hydraulic line 
connection to the disconnect fitting. Accomplishment of the 
installation of retainer plates at each MLG brake disconnect will 
provide an improved installation of the brake disconnect, which keeps 
the brake hose connected to the brake. (The alert service bulletin 
limits the effectivity to Model 767 series airplanes equipped with 
carbon brakes, line positions 132 through 518, inclusive.)
    The FAA has also reviewed and approved Boeing Service Bulletin 767-
32A0126, Revision 1, dated January 13, 1994, that describes procedures 
for performing a visual inspection of the brake rod pin assembly at 
each MLG wheel to detect cracks, bronze transfer, corrosion, chrome 
discoloration, and areas of missing chrome plate; replacement of any 
damaged brake rod pin assembly; modification of the brake rod pin 
assembly; installation of the modified brake rod pin into the brake 
housing and brake rod; and installation of a new brake attach pin 
retainer configuration. The service bulletin also describes a visual 
inspection to detect cracking, deformation, and/or missing pieces of 
material in the brake housing, and the bushings in the end of the brake 
rod; and repair or replacement as necessary. Accomplishment of this 
inspection and modification of the brake rod pin assembly at each MLG 
wheel, inspection of certain MLG bushings, and replacement or repair as 
necessary, will help prevent the possibility of a fracture developing 
in a cross bolt. The manufacturer has installed this modification on 
airplanes (equipped with carbon brakes) in production, starting at line 
number 519 and subsequent. (The service bulletin limits the effectivity 
to Model 767 series airplanes equipped with carbon brakes, line 
positions 132 through 518, inclusive.)
    Since an unsafe condition has been identified that is likely to 
exist or develop on other Model 767 series airplanes of the same type 
design, this AD is being issued to prevent failure of two or more MLG 
brakes, which could adversely affect the stopping performance of the 
airplane. This AD requires the following actions:
    1. Repetitive surface temper etch inspections and fluorescent 
magnetic particle inspections to detect cracks or thermal damage of the 
existing brake rod inner cylinder bolts on the MLG wheels and brakes, 
and replacement of cracked or damaged bolts with new or serviceable 
bolts;
    2. Repetitive visual inspections to detect cracking of the inner 
cylinder fork lug bushings and the brake rod bushings at the inner 
cylinder fork lug end;
    3. Installation of retainer plates at each MLG brake disconnect and 
adjustment of the torque of the ``B''-nut on the hydraulic line 
connection to the disconnect fitting;
    4. A one-time visual inspection of the brake rod pin assembly at 
each MLG wheel to detect cracks, bronze transfer, corrosion, chrome 
discoloration, and areas of missing chrome plate; replacement of any 
damaged brake rod pin assembly with a new or serviceable assembly; 
modification of the brake rod pin assembly; installation of the 
modified brake rod pin into the brake housing and brake rod; and 
installation of a new brake attach pin retainer configuration;
    5. A one-time visual inspection to detect cracking, deformation, 
and/or missing pieces in the bushings in the brake housing, and the 
bushings in the end of the brake rod; and
    6. Subsequent repair or replacement of any cracked and/or deformed 
bushings, and/or any bushings having missing pieces of material.
    The actions are required to be accomplished in accordance with the 
service bulletins described previously.
    This AD allows operation with one-brake-deactivated performance 
decrements for cracked or broken bushings, for operators who comply 
with the requirements of paragraphs (a) through (b)(3) of this AD 
within the acceptable compliance timeframe.
    This AD allows operation with two-brake-deactivated performance 
decrements, for operators who have not accomplished the requirements of 
paragraphs (a) through (b)(3) of this AD within the acceptable 
compliance timeframe. For those operators, this AD requires revising 
the Limitations and Flight Performance Sections of the Airplane Flight 
Manual (AFM) to include two-brake-deactivated performance decrements. 
Three options are provided: the first and second options are simple, 
conservative corrections; the third option, while more complicated, can 
provide a less penalizing correction, depending upon the conditions. 
The effect of this AD is to ensure that flight crews are advised of the 
potential hazard and of the procedures to address it.
    The applicability of this AD is limited to only Model 767 series 
airplanes equipped with carbon brakes.
    Since a situation exists that requires the immediate adoption of 
this regulation, it is found that notice and opportunity for prior 
public comment hereon are impracticable, and that good cause exists for 
making this amendment effective in less than 30 days.

Comments Invited

    Although this action is in the form of a final rule that involves 
requirements affecting flight safety and, thus, was not preceded by 
notice and an opportunity for public comment, comments are invited on 
this rule. Interested persons are invited to comment on this rule by 
submitting such written data, views, or arguments as they may desire. 
Communications shall identify the Rules Docket number and be submitted 
in triplicate to the address specified under the caption ``ADDRESSES.'' 
All communications received on or before the closing date for comments 
will be considered, and this rule may be amended in light of the 
comments received. Factual information that supports the commenter's 
ideas and suggestions is extremely helpful in evaluating the 
effectiveness of the AD action and determining whether additional 
rulemaking action would be needed.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the rule that might 
suggest a need to modify the rule. All comments submitted will be 
available, both before and after the closing date for comments, in the 
Rules Docket for examination by interested persons. A report that 
summarizes each FAA-public contact concerned with the substance of this 
AD will be filed in the Rules Docket.
    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this notice must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 93-NM-209-AD.'' The postcard will be date stamped and 
returned to the commenter.
    The regulations adopted herein will not have substantial direct 
effects on the States, on the relationship between the national 
government and the States, or on the distribution of power and 
responsibilities among the various levels of government. Therefore, in 
accordance with Executive Order 12612, it is determined that this final 
rule does not have sufficient federalism implications to warrant the 
preparation of a Federalism Assessment.
    The FAA has determined that this regulation is an emergency 
regulation that must be issued immediately to correct an unsafe 
condition in aircraft, and is not a ``significant regulatory action'' 
under Executive Order 12866. It has been determined further that this 
action involves an emergency regulation under DOT Regulatory Policies 
and Procedures (44 FR 11034, February 26, 1979). If it is determined 
that this emergency regulation otherwise would be significant under DOT 
Regulatory Policies and Procedures, a final regulatory evaluation will 
be prepared and placed in the Rules Docket. A copy of it, if filed, may 
be obtained from the Rules Docket at the location provided under the 
caption ``ADDRESSES.''

List of Subjects in 14 CFR Part 39

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

Adoption of the Amendment

    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 adding the following new 
airworthiness directive:

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 accel-   corrected accel-  corrected accel-  Corrected accel-
  stop distance      stop distance      stop distance     stop distance 
      (feet)             (feet)            (feet)            (feet)     
------------------------------------------------------------------------
4,000............          3,420            13,000            11,552    
5,000............          4,312            14,000            12,470    
6,000............          5,206            15,000            13,391    
7,000............          6,104            16,000            14,315    
8,000............          7,005            17,000            15,241    
9,000............          7,908            18,000            16,171    
10,000...........          8,815            19,000            17,104    
11,000...........          9,724            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. 

------------------------------------------------------------------------
   All brake op     Adjusted VMBE--     All brake op     Adjusted VMBE--
    VMBE--KIAS            KIAS           VMBE--KIAS           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. 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 Febriary 18, 1994.

    Issued in Renton, Washington, on January 27, 1994.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 94-2336 Filed 2-2-94; 8:45 am]
BILLING CODE 4910-13-U