[Federal Register Volume 61, Number 19 (Monday, January 29, 1996)]
[Rules and Regulations]
[Pages 2703-2705]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-1410]



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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 95-ANE-70; Amendment 39-9489, AD 96-02-04]


Airworthiness Directives; Franklin Model 6A4-150-B3 and 6A4-165-
B3 Reciprocating Engines

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

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SUMMARY: This amendment adopts a new airworthiness directive (AD) that 
is applicable to Franklin Model 6A4-150-B3 and 6A4-165-B3 reciprocating 
engines, installed on the following U.S. registered aircraft: N6209M, 
N74231, and N752C. This action supersedes priority letter AD 94-14-11 
that currently requires engines certified to operate on 91 octane or 
higher avgas to undergo a teardown and analytical inspection for 
detonation damage, and engines certified to operate on 80 octane avgas 
to undergo inspection for evidence of possible internal engine damage. 
This action revises incorrect engine model numbers listed in the 
priority letter AD. This amendment is prompted by updated information 
that has identified the correct engine model numbers. The actions 
specified by this AD are intended to prevent detonation due to low 
octane, which can result in severe engine damage and subsequent 
failure.

DATES: Effective February 13, 1996.
    Comments for inclusion in the Rules Docket must be received on or 
before March 29, 1996.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), New England Region, Office of the Assistant Chief 
Counsel, Attention: Rules Docket No. 95-ANE-70, 12 New England 
Executive Park, Burlington, MA 01803-5299.

FOR FURTHER INFORMATION CONTACT: Locke Easton, Aerospace Engineer, 
Engine and Propeller Standards Staff, FAA, Engine and Propeller 
Directorate, 12 New England Executive Park; telephone (617) 238-7113, 
fax (617) 238-7199.

SUPPLEMENTARY INFORMATION: On June 23, 1994, the Federal Aviation 
Administration (FAA) issued priority letter airworthiness directive 
(AD) 94-14-11, applicable to Franklin Model 6A4-150-B3 and 6A4-165-B3 
reciprocating engines, installed on the following U.S. registered 
aircraft: N6209M, N74231, and N752C. That action requires teardown and 
analytical inspection for engines certified to operate on 91 or higher 
octane aviation gasoline (avgas), and differential compression test and 
examination of the oil filter for engines certified to operate on 80 
octane avgas. That action was prompted by reports of reports of 
aviation gasoline (avgas) being contaminated by Jet A fuel. After 
investigation, the source of the contamination has been determined to 
be the refiner of the avgas. Through its distribution system, the 
refiner inadvertently caused Jet A fuel to be loaded into distribution 
tanks intended for avgas. Contaminated avgas from these distribution 
tanks was then shipped to local fuel distributors. The FAA has 
determined that aircraft with certain Franklin engines installed were 
fueled with this contaminated mixture between May 22 and June 2, 1994, 
at Sacramento Executive (SAC) airport, or between May 18 and June 2, 
1994, at Sacramento Metro (SMF) airport. The list of U.S. registered 
aircraft specified in the applicability paragraph of this AD is based 
on investigation of fueling records secured from the two affected 
airports, which the FAA has determined to represent the population of 
affected engines. That condition, if not corrected, could result in 
detonation due to low octane, which can result in severe engine damage 
and subsequent failure.
    This AD requires engines certified to operate on 91 octane or 
higher avgas to undergo a teardown and analytical inspection for 
detonation damage, and engines certified to operate on 80 octane avgas 
to undergo inspection for evidence of possible internal engine damage. 
Engineering analysis of operating these engines with avgas contaminated 
with Jet A fuel indicates that actual damage to the engine may range 
from unnoticeable to very severe, according to the duration of run, 
engine power level, and level of contamination. Damage may be 
characterized by increased operating temperatures resulting in damaged 
intake valves and burned pistons, and excessive loads imposed by 
detonation. Since internal damage may not be assessed by any other 
method, engines certified to operate on 91 octane or higher avgas must 
undergo a teardown and analytical inspection and any parts showing 
signs of detonation damage must be replaced. 

[[Page 2704]]
Investigation revealed the lowest octane level of the contaminated fuel 
to be 83 octane, therefore engines certified to operate on 80 octane 
avgas need not undergo a teardown and analytical inspection unless 
evidence of internal engine damage is present by the required 
differential compression test and examination of the oil filter for 
metal particles. The refiner has advised the FAA that it may pay for 
any reasonable expense associated with the inspection and/or 
disassembly in accordance with the mechanic's and manufacturer's 
recommendations.
    Since an unsafe condition has been identified that is likely to 
exist or develop on other engines of this same type design, this AD 
supersedes priority letter AD 94-14-11 to revise incorrect engine model 
numbers listed in the priority letter AD.
    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 should 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 95-ANE-70.'' 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 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 U.S.C. 106(g), 40101, 40113, 44701.


Sec. 39.13  [Amended]

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

96-02-04  Franklin: Amendment 39-9489. Docket No. 95-ANE-70. 
Supersedes AD 94-14-11.

    Applicability: Franklin Model 6A4-150-B3 and 6A4-165-B3 
reciprocating engines, installed on the following U.S. registered 
aircraft: N6209M, N74231, and N752C.

    Note: This airworthiness directive (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 (c) to request approval from the 
Federal Aviation Administration (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. detonation due to low octane, which can result in severe 
engine damage and subsequent failure, accomplish the following:
    (a) For engines that are certified to operate on only 91 or 
higher octane aviation gasoline (avgas) within the next 2 hours time 
in service (TIS) after the effective date of this airworthiness 
directive (AD) perform an engine teardown and analytical inspection, 
and replace with serviceable parts as necessary in accordance with 
the applicable overhaul manuals.
    (b) For engines that are certified to operate on 80 octane 
avgas, within the next 2 hours TIS after the effective date of this 
AD conduct a differential compression test on all cylinders in 
accordance with the applicable maintenance manuals, and examine the 
oil filter by cutting the oil filter apart and spreading the filter 
paper out to look for metal particles. If metal particles are 
present, or if one or more cylinders shows unacceptable compression 
as specified in the applicable maintenance manuals, perform an 
engine teardown and analytical inspection, and replace with 
serviceable parts as necessary in accordance with the applicable 
overhaul manuals.

    Note: Additional guidance for conducting differential 
compression tests is contained in paragraph 692 of Advisory Circular 
(AC) No. 43.13-1A, dated 1988.

    (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, Engine and Propeller Standards 
Staff. The request should be forwarded through an appropriate FAA 
Maintenance Inspector, who may add comments and then send it to the 
Manager, Engine and Propeller Standards Staff.

    Note: Information concerning the existence of approved 
alternative methods of compliance with this airworthiness directive, 
if any, may be obtained from the Engine and Propeller Standards 
Staff.

    (d) Special flight permits may be issued in accordance with 
sections 21.197 and 21.199 

[[Page 2705]]
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.
    (e) This amendment supersedes priority letter AD 94-11-11, 
issued June 23, 1994.
    (f) This amendment becomes effective on February 13, 1996.

    Issued in Burlington, Massachusetts, on January 11, 1996.
Jay J. Pardee,
Manager, Engine and Propeller Directorate, Aircraft Certification 
Service.
[FR Doc. 96-1410 Filed 1-26-96; 8:45 am]
BILLING CODE 4910-13-U