[Federal Register Volume 59, Number 42 (Thursday, March 3, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-4837]


[[Page Unknown]]

[Federal Register: March 3, 1994]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 92-ANE-32; Amendment 39-8843; AD 94-05-05]

 

Airworthiness Directives; Teledyne Continental Motors Models C75, 
C85, C90, C125, C145, O-200, O-300, and GO-300 Series Reciprocating 
Engines

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment adopts a new airworthiness directive (AD), 
applicable to Teledyne Continental Motors (TCM) Models C75, C85, C90, 
C125, C145, O-200, O-300, and GO-300 series reciprocating engines, that 
requires inspection of the cylinder rocker shaft bosses for cracks, and 
inspection of the cylinder rocker shaft for looseness and replacement, 
if necessary, with a serviceable part. This amendment is prompted by 
reports of cracked or improperly repaired cylinder rocker shaft bosses. 
The actions specified by this AD are intended to prevent engine power 
loss and engine failure.

EFFECTIVE DATE: May 2, 1994.

FOR FURTHER INFORMATION CONTACT: Jerry Robinette, Aerospace Engineer, 
Atlanta Aircraft Certification Office, FAA, Small Airplane Directorate, 
1669 Phoenix Parkway, Atlanta, GA 30349; telephone (404) 991-3810, fax 
(404) 991-3606.

SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal 
Aviation Regulations to include an airworthiness directive (AD) that is 
applicable to Teledyne Continental Motors (TCM) Models C75, C85, C90, 
C125, C145, O-200, and O-300 series reciprocating engines was published 
in the Federal Register on June 2, 1993 (58 FR 31348). That action 
proposed to require fluorescent penetrant or etching inspections of the 
cylinder rocker shaft bosses for cracks, and dimensional inspections of 
the cylinder rocker shaft bosses for looseness, at the next overhaul, 
in accordance with TCM Overhaul Manual Form X-30013, dated June 1982, 
applicable to TCM Models C125, C145, and O-300 series engines; and TCM 
Overhaul Manual Form X-30010, dated January 1984, applicable to TCM 
Models C75, C85, C90, and O-200 series engines. If the cylinder rocker 
shaft bosses are cracked, the cylinder must be replaced. Modified 
cylinders must be further inspected for cracks that may have been 
introduced during the repair process. Cylinders with loose rocker 
shafts must be replaced with serviceable cylinders, or modified by 
installing bushings.
    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. Due consideration has been given to 
the comments received.
    One commenter states that the AD should require compliance at the 
next 100 hour or annual inspection, whichever occurs first. The 
commenter further states that the AD should require visual inspection 
for wear, broken bosses, or loose bushings at the earlier compliance 
time because cylinders with cracked bosses or loose bushing will likely 
fail before the cylinder requires overhaul. The FAA does not concur. 
Service Difficulty Reports and engineering analysis do not indicate 
that the shorter compliance time is necessary, and the comment did not 
include any data as a basis for the shorter compliance time. 
Furthermore, it is unlikely that a visual inspection without 
disassembly could detect cracks or looseness in the cylinder rocker 
shaft bosses.
    The commenter further states that the TCM GO-300 series engines 
should be included in the AD. Production of new cylinders has been 
standardized by manufacturing the TCM GO-300 type cylinder only for use 
on all C-75 through C-145, as well as the O-200 and O-300 series 
engines. The commenter maintains that used GO-300 cylinder assemblies 
may find their way onto other engines. The GO-300 shares nearly 
identical valve train components with the other engines and is subject 
to the same type of rocker boss wear and possible failures. The FAA 
concurs. The GO-300 cylinders have been added to the applicability 
paragraph of this AD.
    The commenter further states that TCM Service Bulletin (SB) No. 
M73-13 specifies a minimum edge thickness for the center rocker bosses 
only. The commenter argues that this requirement for minimum thickness 
should be redefined to be a minimum thickness anywhere on any boss 
because many cylinders have bosses with adequate material on the edges 
of the center bosses, but very little material between the edges. The 
commenter concludes by stating that outer bosses, also require close 
scrutiny for thickness, and if an outer boss fails, the center boss 
will likely be overloaded and also fail. The FAA does not concur. The 
center bosses are thinner by design and will therefore wear to the 
limit sooner than the outer bosses. If the center bosses have the 
correct edge to wall thickness, then the outer bosses will be correct 
also.
    The commenter further states that consideration should be given to 
securing rocker boss repair bushings with a dowel pin to prevent 
rotation after installation. The commenter argues that any lack of 
concentricity between bushing ID and OD can severely overload bosses if 
one or more bushings rotate after installation. The FAA does not 
concur. If the repair is accomplished correctly, the bushing will be 
pressed in and this press fit will prevent rotation.
    The commenter further states that when performing inspections for 
cracked bosses on cylinders that have been removed from the engine, dye 
penetrant inspection should be allowed in addition to the fluorescent 
penetrant inspection. The commenter maintains that dye penetrant 
inspection is quite effective and reliable when properly performed and 
is in widespread use by approved cylinder head repair facilities. The 
FAA concurs. Dye penetrant inspection has been added to the AD as an 
option for compliance. In addition, the FAA has added industry-accepted 
procedures to the AD for performing dye penetrant, fluorescent 
penetrant, and etching inspections in order to standardize the method 
of inspection.
    After careful review of the available data, including the comments 
noted above, the FAA has determined that air safety and the public 
interest require the adoption of the rule with the changes described 
previously. The FAA has determined that these changes will neither 
increase the economic burden on any operator nor increase the scope of 
the AD.
    The FAA estimates that 35,600 engines installed on aircraft of U.S. 
registry would be affected by this AD, approximately 20,000 four-
cylinder engines and 15,600 six-cylinder engines. The FAA estimates 
that it will take approximately one-half work hour per cylinder to 
inspect or install the bushings, and that the average labor rate is $55 
per work hour. Required parts will cost approximately $11 per cylinder. 
Based on these figures, the cost impact of the AD for four-cylinder 
engines is estimated to be $154 per engine, the cost impact of the AD 
for six-cylinder engines is estimated to be $231 per engine, and the 
total cost impact of the AD on U.S. operators is estimated to be 
$6,683,600.
    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.
    For the reasons discussed above, I certify that this action (1) is 
not a ``significant regulatory action'' under Executive Order 12866; 
(2) is not a ``significant rule'' under DOT Regulatory Policies and 
Procedures (44 FR 11034, February 26, 1979); and (3) will not have a 
significant economic impact, positive or negative, on a substantial 
number of small entities under the criteria of the Regulatory 
Flexibility Act. A final evaluation has been prepared for this action 
and it is contained in the Rules Docket. A copy of it 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:

94-05-05  Teledyne Continental Motors: Amendment 39-8843. Docket 92-
ANE-32.

    Applicability: Teledyne Continental Motors (TCM) Model C75, C85, 
C90, C125, C145, O-200, O-300, and GO-300 series reciprocating 
engines installed on but not limited to American Champion models 
7BCM, 7CCM, 7DC, S7DC, S7CCM, 7EC, S7EC, 7FC, 7JC, and 7ECA; Cessna 
Models 120, 140, 150, 170, 172, 172A-H, and 175; Luscombe Models 8E, 
8F, and T-8F; Maule Models Bee Dee M-4, M-4, M-4C, M-4S, M-4T, M-4-
210, M-4-210C, M-4-210S, M-4-210T, and M-5-210C; Piper Models PA-18 
and PA-19; Swift Models GC-1A and GC-1B; Univair (Erco) Models 415-
D, E, and G; Univair (Forney) Models F-1 and F-1A; Univair (Alon) 
Model A-2 and Univair (Mooney) Model M-10 aircraft.
    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent engine power loss and engine failure, accomplish the 
following:
    (a) At the next cylinder or engine overhaul after the effective 
date of this AD, inspect the cylinder rocker shaft bosses for cracks 
using one of the following methods, and if cracked replace with a 
serviceable cylinder:

    Note: Certain cylinder cracks may be repaired by FAA-approved 
repair stations specifically rated to do those repairs.

    (1) Fluorescent penetrant inspection, as follows:
    (i) The penetrant shall be a nontoxic, noncorrosive, highly 
fluorescent liquid capable of penetrating fine discontinuities and, 
for aluminum castings, conforming to Aerospace Material 
Specification (AMS) 3156. If a darkened enclosure is not used for 
examination, AMS 3157 penetrant shall be used.
    (ii) The emulsifier shall be composed of suitable oil or oil-
like components together with such additives as are necessary to 
provide a stable, nontoxic, noncorrosive, oil-miscible, oil-
emulsifying solution. Emulsifier shall not be used when AMS 3156 is 
used.
    (iii) The developer shall be a highly absorbent, nonfluorescent 
and nontoxic powder, capable of being used dry or a similar powder 
capable of being suspended in water. When the suspension is used, 
the powder shall be thoroughly mixed with water to a concentration, 
unless otherwise permitted, of not less than 0.2 lb per gallon and a 
uniform distribution maintained by mechanical agitation.
    (iv) The penetrant, the emulsifier (if used) and the developer 
shall be checked as often as necessary to maintain proper control. 
The penetrant shall be discarded if it shows a noticeable loss in 
penetrating power or marked contamination or when wax begins to form 
on the sides of the tank and dip basket.
    (v) A darkness booth or a similar darkness area with a filtered 
black light shall be provided. The black light shall be at least 
equal to that produced by a 100 watt mercury vapor projection spot 
lamp equipped with a filter to transmit wave lengths of between 3200 
and 4000 Angstrom units and absorb substantially all visible light. 
The intensity of the light at normal working distance shall be as 
specified by the purchaser but in no case shall be lower than 580 
micro-watts per square centimeter as measured with an appropriate 
black light meter.
    (vi) All parts shall be cleaned and dried in such a manner as to 
leave them free from grease, oil, soaps, alkalies and other 
substances which would interfere with inspection. Vapor degreasing 
is generally suitable for this purpose.
    (vii) Parts shall be immersed in the penetrant or shall be 
sprayed or brushed with the penetrant and shall be allowed to remain 
immersed in the penetrant or to stand for sufficient time to allow 
satisfactory penetration into all discontinuities. This time shall, 
unless otherwise specified, not be less than 5 minutes. The time for 
immersion or standing will depend upon the character and fineness of 
the discontinuities, the effectiveness of penetration increasing 
with time. Parts may be resprayed or re-immersed after standing to 
increase sensitivity and aid in removal of penetrant.
    (viii) Parts shall be removed from the penetrant and cleaned 
thoroughly using a medium which will remove penetrant from the 
surface of parts; washing with water shall be used when the 
penetrant is water washable or when an emulsifying agent is applied 
to surfaces of parts to render the penetrant water washable. When 
emulsifiers are used, the parts shall be dipped in the emulsifier 
and removed slowly for draining or shall be sprayed with emulsifier 
and drained. Unless otherwise specified, the combined dipping and 
draining time shall be 1 to 5 minutes. When other than water 
washable penetrants are used, the penetrant shall be removed with a 
suitable cleaner or a suitable cleaner and lint-free cloths. During 
cleaning, the parts may be viewed under a suitable black light to 
ensure removal of the penetrant from the subrace of the part. 
Excessive cleaning which would remove the penetrant from 
discontinuities shall be avoided.
    (ix) When a wet developer is used, the developer shall be 
applied to the parts, immediately after washing, by immersing the 
parts in the tank containing the water-suspended powder or by 
spraying or flowing the suspension onto the parts. The suspension 
shall be suitably agitated either during or immediately prior to 
application to parts. Immersed parts shall be removed from the wet 
developer; excess developer shall be allowed to drain off all parts. 
Special care shall be taken to remove excess developer from pockets, 
recesses, holes, threads, and corners so that the developer will not 
mask indications.
    (x) When a dry developer or no developer is used, the parts 
shall be dried as thoroughly as possible by exposure to clean air. 
Drying of parts may be accomplished by evaporation at room 
temperature or by placing the parts in a circulating warm air oven 
or in the air stream of a hot air dryer. Excessive drying time or 
part temperatures higher than 80 deg.C (180 deg.F) should be avoided 
to prevent evaporation of the penetrant.
    (xi) When a dry developer is used, the developing powder shall 
be applied uniformly over the areas of the parts to be inspected by 
either dusting or powder-box immersion.
    (xii) After sufficient time has been allowed to develop 
indications, parts shall be examined under a black light. 
Examination shall be made in a darkened enclosure unless AMS 3157 
penetrant is used, in which case examination may be made under 
normal shop lighting but shaded from direct sunlight.
    (xiii) When greater sensitivity is desired, the parts may be 
heated to 65 deg.-85 deg.C (150 deg.-185 deg.F) before immersion in 
the penetrant and/or before black light examination. To prevent 
evaporation, preheated parts shall remain fully immersed in the 
penetrant until cooled.
    (xiv) Parts shall be cleaned, as necessary, to remove penetrant 
and developer.
    (xv) Interpretation of the indications revealed by this 
inspection procedure and final disposition of the parts shall be the 
responsibility of only qualified personnel having experience with 
fluorescent penetrant inspection.
    (xvi) Parts having discontinuities (cracks) shall be rejected.
    (2) Dye penetrant inspection, as follows:

    Note: Military Specification MIL-I-6866 and American Society of 
Testing Materials specifications ASTM E1417-93 and E165-9 contain 
additional information on dye penetrant inspection processes.

    (i) Preparation: clean and dry all parts in such a manner as to 
leave the surfaces free from grease, oil, soaps, alkalies, and other 
substances which would interfere with inspection. Vapor degreasing 
is generally suitable for this purpose.
    (ii) Penetrant Application Procedure: after preparation, spray 
or brush the parts with the penetrant, and allow to stand for not 
less than 5 minutes. The effectiveness of the penetrant increases if 
left standing for a longer time, as the penetrant will reach finer 
discontinuities.
    (iii) Penetrant Cleaning: clean the parts thoroughly using a 
medium which will remove penetrant from the surfaces of parts; wash 
with water when the penetrant is water soluble. When other than 
water soluble penetrants are used, the penetrant shall be removed 
with a suitable cleaner. Avoid excessive cleaning which would remove 
the penetrant from discontinuities.
    (iv) Drying: dry the parts as thoroughly as possible. Drying of 
parts may be accomplished by evaporation at room temperature or by 
placing the parts in a circulating warm air oven or in the air 
stream of a hot air dryer. Avoid excessive drying time or drying 
temperatures above 75 deg.C (165 deg.F) to prevent excessive 
evaporation of the penetrant. If heat is used for drying parts, cool 
parts to approximately 50 deg.C (120 deg.F) before proceeding to the 
developing procedure.
    (v) Developing: apply the developer to the dry parts as lightly 
and as evenly as possible, using as thin a coating of developer as 
is possible. A translucent film is adequate. Mix wet developer by 
agitation immediately prior to applying it. After applying the 
developer, take care that no penetrant indication is disturbed or 
obliterated in subsequent handling.
    (vi) Examination: examine the developed penetrant indications in 
accordance with the dye penetrant manufacturer's instructions. 
Examine parts for indications of discontinuities open to the 
surface.
    (vii) Final cleaning: clean the parts following the inspection 
to remove penetrant and developer.

    Note 1: Caution: because of differences among penetrants, take 
care to ensure that the final cleaner, the penetrant, the penetrant 
remover, and the developer are suitable for use with each other.

    Note 2: Caution: all penetrant materials should be kept as free 
from moisture as possible.

    Note 3: Caution: most penetrants, cleaning agents, and developer 
suspensions are low flash point material; use caution to prevent 
fires.

    (3) Etching inspection, as follows:
    (i) For TCM C75, C85, C90, and O-200 series engines, in 
accordance with paragraph 13-7 of TCM Overhaul Manual Form X-30010, 
dated January 1984.
    (ii) For TCM C125, C145, O-300, and GO-300 series engines, in 
accordance with paragraphs 5(b)(1), 5(b)(2), and 5(b)(3) of TCM 
Overhaul Manual Form X-30013, dated June 1982.
    (b) At the next cylinder or engine overhaul after the effective 
date of this AD, dimensionally inspect cylinders for looseness of 
the rocker shaft in accordance with page 22, paragraph 5, and Table 
IX of TCM Overhaul Manual Form X-30013, dated June 1982, for TCM 
Models C125, C145, O-300, and GO-300 series engines; page 75, 
paragraph 13-6, and the dimensions table in paragraph 13-8 of TCM 
Overhaul Manual Form X-30010, dated January 1984, for TCM Models 
C75, C85, C90, and O-200 series engines; as applicable.
    (1) Cylinders that do not exhibit dimensional looseness of the 
rocker shaft beyond the limits specified in the applicable TCM 
overhaul manual may be returned to service.
    (2) For cylinders that exhibit dimensional looseness of the 
rocker shaft, beyond the limits specified in the applicable TCM 
overhaul manual, accomplish the following:
    (i) Replace with a serviceable cylinder; or
    (ii) Install bushings in accordance with the instructions on 
page 27 of TCM Overhaul Manual, Form X-30013, dated June 1982, for 
TCM Models C125, C145, O-300, and GO-300 series engines; or the 
instructions on page 85 of TCM Overhaul Manual Form X-30010, dated 
January 1984, for TCM Models C75, C85, C90, and O-200 series 
engines; as applicable.
    (iii) After repairing a cylinder perform an additional 
inspection of the cylinder rocker shaft bosses for cracks using 
fluorescent penetrant, dye penetrant, or etching methods, and 
replace, if necessary, with a serviceable cylinder.
    (c) Thereafter, at each subsequent cylinder or engine overhaul, 
reinspect cylinder rocker bosses and rocker shafts in accordance 
with paragraphs (a) and (b) of this AD.
    (d) 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, Atlanta Aircraft Certification 
Office. The request should be forwarded through an appropriate FAA 
Maintenance Inspector, who may add comments and then send it to the 
Manager, Atlanta Aircraft Certification Office.

    Note: Information concerning the existence of approved 
alternative methods of compliance with this airworthiness directive, 
if any, may be obtained from the Atlanta Aircraft Certification 
Office.

    (e) 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.
    (f) This amendment becomes effective on May 2, 1994.

    Issued in Burlington, Massachusetts, on February 18, 1994.
Jay J. Pardee,
Manager, Engine and Propeller Directorate, Aircraft Certification 
Service.
[FR Doc. 94-4837 Filed 3-2-94; 8:45 am]
BILLING CODE 4910-13-P