[Federal Register Volume 60, Number 164 (Thursday, August 24, 1995)]
[Proposed Rules]
[Pages 43995-43997]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-20991]



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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 93-ANE-08]


Airworthiness Directives; Teledyne Continental Motors IO-360, 
TSIO-360, LTSIO-360, IO-520, and TSIO-520 Series Reciprocating Engines

AGENCY: Federal Aviation Administration, DOT.

ACTION: Supplemental notice of proposed rulemaking; reopening of 
comment period.

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SUMMARY: This notice revises a proposal to issue an airworthiness 
directive (AD), applicable to certain Teledyne Continental Motors (TCM) 
IO-360, TSIO-360, LTSIO-360, IO-520, and TSIO-520 series engines. 
Airworthiness directive 87-23-08 currently requires ultrasonic 
inspections for sub-surface fatigue cracks in crankshafts installed in 
TCM IO-520 and TSIO-520 series engines, and replacement of the 
crankshaft if a crack is found. The proposed AD would have superseded 
AD 87-23-08 by expanding the applicability of the AD to include IO-360, 
TSIO-360, LTSIO-360, and LTSIO-520 series engines, requiring the 
removal of all crankshafts manufactured using the airmelt process on 
all of the affected engine models, and replacement with crankshafts 
manufactured using the vacuum arc remelt (VAR) process. The proposed AD 
would have eliminated the ultrasonic inspections for the TCM IO-520 and 
TSIO-520 series engines. That proposed rule was prompted by reports of 
crankshaft failures due to sub-surface fatigue cracking on engines that 
had been inspected in accordance with the current AD. This action 
revises the proposed rule by superseding AD 87-23-08 and incorporating 
the ultrasonic inspection requirements in the proposed AD. The proposed 
action would still require removal of crankshafts manufactured using 
the airmelt process and replacement with crankshafts manufactured using 
the VAR process. The actions specified by this proposed AD are intended 
to prevent crankshaft failure and subsequent engine failure.

DATES: Comments must be received by October 23, 1995.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), New England Region, Office of the Assistant Chief 
Counsel, Attention: Rules Docket No. 93-ANE-08, 12 New England 
Executive Park, Burlington, MA 01803-5299. Comments may be inspected at 
this location between 8 a.m. and 4:30 p.m., Monday through Friday, 
except Federal holidays.
    The service information referenced in the proposed rule may be 
obtained from Teledyne Continental Motors, P.O. Box 90, Mobile, AL 
36601; telephone (334) 438-3411. This information may be examined at 
the FAA, New England Region, Office of the Assistant Chief Counsel, 12 
New England Executive Park, Burlington, MA.

FOR FURTHER INFORMATION CONTACT: Jerry Robinette, Aerospace Engineer, 
Atlanta Aircraft Certification Office, FAA, Small Airplane Directorate, 
Campus Building, 1701 Columbia Ave., Suite 2-160, College Park, GA 
30337-2748; telephone (404) 305-7371, fax (404) 305-7348.

SUPPLEMENTARY INFORMATION:

Comments Invited

    Interested persons are invited to participate in the making of the 
proposed rule by submitting such written data, views, or arguments as 
they may desire. Communications should identify the Rules Docket number 
and be submitted in triplicate to the address specified above. All 
communications received on or before the closing date for comments, 
specified above, will be considered before taking action on the 
proposed rule. The proposals contained in this notice may be changed in 
light of the comments received.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the proposed 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 summarizing each FAA-public contact concerned with 
the substance of this proposal 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 

[[Page 43996]]
statement is made: ``Comments to Docket Number 93-ANE-08.'' The 
postcard will be date stamped and returned to the commenter.

Availability of NPRMs

    Any person may obtain a copy of this NPRM by submitting a request 
to the FAA, New England Region, Office of the Assistant Chief Counsel, 
Attention: Rules Docket No. 93-ANE-08, 12 New England Executive Park, 
Burlington, MA 01803-5299.

Discussion

    A proposal to amend part 39 of the Federal Aviation Regulations (14 
CFR part 39) to add an airworthiness directive (AD), applicable to 
certain Teledyne Continental Motors (TCM) IO-360, TSIO-360, LTSIO-360, 
IO-520, TSIO-520, and LTSIO-520 series engines, was published as a 
notice of proposed rulemaking (NPRM) in the Federal Register on July 
23, 1993 (58 FR 39748). That proposal would have superseded AD 87-23-
08, Amendment 39-5735 (52 FR 41937, October 30, 1987), which currently 
requires ultrasonic inspection of TCM IO-520 and TSIO-520 series 
engines for sub-surface cracks in the crankshaft, and replacement of 
the crankshaft, if a crack is found. The proposed AD would have 
eliminated the required ultrasonic inspections, but would have required 
removal of crankshafts that were manufactured using the airmelt process 
and required replacement with crankshafts that were manufactured using 
the vacuum arc remelt (VAR) process. The proposed AD would have also 
expanded the affected population of engines to add the TCM IO-360, 
TSIO-360, LTSIO-360, and LTSIO-520 series engines to the IO-520 and 
TSIO-520 series engines affected by AD 87-23-08. That proposal was 
prompted by reports of crankshaft failures due to subsurface fatigue 
cracking on engines that had been inspected in accordance with AD 87-
23-08. That condition, if not corrected, could result in crankshaft 
failure and subsequent engine failure.
    Since the issuance of that NPRM, the Federal Aviation 
Administration (FAA) has received numerous unfavorable comments, 
centering on the FAA's data and the economic impact of the proposed AD 
on small entities. The principal commenter, the Aeronautical Repair 
Station Association (ARSA), feels that the data presented by the FAA is 
not representative of the entire fleet. As a result, the FAA has 
decided to issue this Supplemental NPRM that revises the proposed AD 
and publishes additional data.
    Teledyne Continental Motors has utilized two different processes in 
manufacturing crankshafts. Initially, TCM used an airmelt process, but 
later switched to the VAR process. The VAR process assures a better 
steel with less likelihood of impurities.
    The crankshaft failures addressed by this AD are attributed to sub-
surface fatigue cracks on engines with crankshafts having the three 
rear main bearing journal diameters as follows: for the 360 series 
engines 2.250 to 2.375 inches and for the IO/TSIO-520 series engines 
2.375 to 2.625 inches. The FAA has received reports of crankshaft 
failures due to sub-surface fatigue cracks on 43 TCM IO-520 or TSIO-520 
series engines and 9 IO-360 or TSIO-360 series engines. There are 
approximately 18,000 airmelt and 25,000 VAR TCM IO-520 or TSIO-520 
series crankshafts in service as of February 1994. Between May 1986 and 
February 1994, on TCM IO-520 or TSIO-520 series engines, there were 40 
failures of airmelt crankshafts and 3 failures of VAR crankshafts. In 
addition, there are approximately 5,000 airmelt and 10,800 VAR TCM IO-
360 or TSIO-360 series crankshafts in service as of February 1994. 
During the same time frame there were 8 failures of airmelt crankshafts 
and 1 failure of a VAR crankshaft on TCM IO-360 or TSIO-360 series 
engines.
    The Service Difficulty Report (SDR) database does not contain many 
of these failures and therefore was not used for this analysis. In 
addition, the SDR database contains the reports of service difficulties 
as submitted, and, therefore, a large number of those reports amount to 
the unconfirmed opinion of the submitter as to the cause of the 
failure. Further, the listings in the SDR database do not identify 
cracks as being sub-surface fatigue cracks, or, for example, cracks 
originating from manufacturing defects or resulting from propeller 
strikes. Lastly, the mix of VAR and airmelt crankshafts in service 
cannot be determined from the SDR database. The data used for this 
analysis, on the other hand, is gathered from sources such as FAA 
witnessed ``teardown'' reports and warranty claims, and pertains only 
to confirmed sub-surface fatigue cracks with the type crankshaft, VAR 
or airmelt, clearly identified.
    The FAA has determined, however, that the ultrasonic inspections of 
crankshafts on TCM IO-520 and TSIO-520 series engines required by AD 
87-23-08 should remain in order to continue to detect any sub-surface 
fatigue cracks that may occur in those crankshafts, regardless of 
manufacturing process. Therefore, this proposal will supersede AD 87-
23-08 and would have the effect of making the repetitive ultrasonic 
inspection requirements applicable to all IO/TSIO/LTSIO-360 and IO/
TSIO/LTSIO-520 series engines with small rear main bearing journals 
while requiring replacement of airmelt crankshafts with VAR crankshafts 
on all affected engine models at the next overhaul.
    In addition, many commenters expressed general concern about the 
calculated economic impact of the proposed AD, and some specifically 
noted that they believe the price of the VAR crankshafts shown in the 
NPRM, $2,200, to be artificially low. The FAA disagrees. The FAA used 
the replacement cost of a crankshaft as reported by TCM, which has 
priced VAR crankshafts at a level to encourage owners to replace 
airmelt crankshafts with VAR crankshafts. TCM has also informed the FAA 
that the price will be competitively maintained; the FAA notes that 
TCM's last general price increase in May 1994 did not affect these 
crankshafts. While this price may differ significantly from the price 
that other manufacturers set for crankshafts on other engines, the FAA 
believes that $2,200 is a reasonable estimate of the replacement cost 
of a crankshaft on the affected engines.
    The FAA has reviewed and approved the technical contents of TCM 
Mandatory Service Bulletin (SB) No. M92-16, dated September 29, 1992, 
that describes procedures for determining if crankshafts were 
manufactured using the airmelt process or VAR process.
    Since an unsafe condition has been identified that is likely to 
exist or develop on other engines of this same type design, the 
proposed AD would require determining if the crankshafts installed on 
certain TCM IO-360, TSIO-360, LTSIO-360, IO-520, and TSIO-520 series 
engines were manufactured using the airmelt or VAR process, and 
replacing all crankshafts manufactured using the airmelt process with 
serviceable crankshafts manufactured using the VAR process at the next 
engine overhaul. The proposed AD would also require repetitive 
ultrasonic inspections of certain VAR crankshafts, and replacement, if 
a crack is found.
    Since this change revises significantly the originally proposed 
rule, the FAA has determined that it is necessary to reopen the comment 
period to provide additional opportunity for public comment.
    The FAA estimates that 15,500 engines installed on aircraft of U.S. 
registry would be affected by this proposed AD, that it would take 
approximately 1 work hour per engine 

[[Page 43997]]
to determine the type of crankshaft, and that the average labor rate is 
$60 per work hour. Required parts would cost approximately $2,200 per 
engine to replace the crankshaft. In addition, the FAA estimates that 
it would cost $200 to perform the ultrasonic inspection at crankshaft 
removal including the costs of shipping and handling. The FAA estimates 
that approximately 10% of the affected engines will be overhauled per 
year. Based on these figures, the total annual cost impact of the 
proposed AD on U.S. operators is estimated to be $3,813,000.
    The regulations proposed herein would 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 
proposal would not have sufficient federalism implications to warrant 
the preparation of a Federalism Assessment.
    For the reasons discussed above, I certify that this proposed 
regulation (1) is not a ``significant regulatory action'' under 
Executive Order 12866; (2) is not a ``significant rule'' under the DOT 
Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); 
and (3) if promulgated, 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 copy of the draft 
regulatory evaluation prepared for this action is contained in the 
Rules Docket. A copy of it may be obtained by contacting the Rules 
Docket at the location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

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

PART 39--AIRWORTHINESS DIRECTIVES

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

    Authority: 49 USC 106(g), 40101, 40113, 44701.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by adding the following new 
airworthiness directive:

    Teledyne Continental Motors: Docket No. 93-ANE-08.

    Applicability: Teledyne Continental Motors (TCM) I0-360, TSIO-
360, LTSIO-360, IO-520, and TSIO-520 series engines built on or 
prior to December 31, 1980; rebuilt I0-360, TSIO-360, LTSIO-360, IO-
520, and TSIO-520 series engines with serial numbers lower than 
those listed in TCM Mandatory Service Bulletin (SB) No. M92-16, 
dated September 29, 1992; and factory overhauled I0-360, TSIO-360, 
LTSIO-360, IO-520, and TSIO-520 series engines with serial numbers 
of 901202H and lower. These engines are installed on but not limited 
to Beech Models 95-C55, 95-C55A, D55, D55A, E55, E55A, 58, 58A, 58P, 
58PA, 58TC, and 58TCA; and Beech Models S35, V35, V35A, V35B, E33A, 
E33C, 35-C33A, 36, A36, F33A, F33C, and A36TC; Bellanca 17-30A; 
Cessna Models 172XP, 188, A185, A188, 206, T206, 207, T207, 210, 
T210, P210, 310R, T310P, T310Q, T310R, 320D, 320E, 320F, 336, 337, 
T337, P337, 340, 401, 402, 414, and T41B/C; Colemill Conversion of 
Commander 500A; Commander 2000; Goodyear Airship Blimp 22; Maule 
Model M-4; Mooney Models M20-K; Navion H; Pierre Robin HR100; Piper 
Models PA-28-201T, PA28R-201T, PA28RT-201T, PA34-200T, PA34-220T; 
Prinair Dehavilland Heron; and Reims Models FR172, F337, FT337.

    Note: This AD applies to each engine identified in the preceding 
applicability provision, regardless of whether it has been modified, 
altered, or repaired in the area subject to the requirements of this 
AD. For engines that have been modified, altered, or repaired so 
that the performance of the requirements of this AD is affected, the 
owner/operator must use the authority provided in paragraph (b) to 
request approval from the FAA. This approval may address either no 
action, if the current configuration eliminates the unsafe 
condition, or different actions necessary to address the unsafe 
condition described in this AD. Such a request should include an 
assessment of the effect of the changed configuration on the unsafe 
condition addressed by this AD. In no case does the presence of any 
modification, alteration, or repair remove any engine from the 
applicability of this AD.

    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent crankshaft failure and subsequent engine failure, 
accomplish the following:
    (a) At the next engine overhaul or whenever the crankshaft is 
next removed from the engine, after the effective date of this AD, 
whichever occurs first, determine if the crankshaft was manufactured 
using the airmelt or vacuum arc remelt (VAR) process in accordance 
with the identification procedures described in TCM Mandatory SB No. 
M92-16, dated September 29, 1992. If the crankshaft was manufactured 
using the airmelt process, or if the manufacturing process is 
unknown, prior to further flight, remove the crankshaft from service 
and replace with a serviceable crankshaft manufactured using the VAR 
process.
    (b) For all engine models with VAR crankshafts identified in TCM 
Mandatory SB No. M92-16 dated September 29, 1992, regardless of 
serial number: at the next and every subsequent crankshaft removal 
from the engine case or installation of a replacement crankshaft, 
prior to crankshaft installation in the engine, conduct an 
ultrasonic inspection of the crankshaft in accordance with TCM 
Service Bulletin No. M87-5, Revision 1, dated May 25, 1987, and 
Crankshaft Ultrasonic Inspection Procedure, Form X30554, dated 
February 1981.
    (1) If a crack is found, replace the crankshaft with a 
serviceable VAR crankshaft.
    (2) If no crack is found, mark the propeller mounting flange in 
accordance with TCM Service Bulletin No. M87-5, Revision 1, dated 
May 25, 1987.

    Note: Accomplishment of the ultrasonic inspection does not set 
aside any requirements for magnaflux or other inspections specified 
in TCM overhaul manuals.

    (c) 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.

    (d) Special flight permits may be issued in accordance with 
sections 21.197 and 21.199 of the Federal Aviation Regulations (14 
CFR 21.197 and 21.199) to operate the aircraft to a location where 
the requirements of this AD can be accomplished.

    Issued in Burlington, Massachusetts, on August 17, 1995.
Jay J. Pardee,
Manager, Engine and Propeller Directorate, Aircraft Certification 
Service.
[FR Doc. 95-20991 Filed 8-23-95; 8:45 am]
BILLING CODE 4910-13-U