AD 98-13-10

This amendment adopts a new airworthiness directive (AD) that applies to all Cessna Aircraft Company (Cessna) Model 182S airplanes. This AD requires repetitively inspecting all engine exhaust muffler end plates (four total) for cracks and replacing any muffler where an end plate is found cracked. The AD also requires fabricating and installing a placard that specifies immediately inspecting all engine exhaust muffler end plates any time the engine backfires upon start-up. This AD is the result of incidents where cracks were found in an engine exhaust muffler end plate on several of the affected airplanes. These cracks were caused by high stresses imposed on the attachment of the exhaust at the area of the firewall. The actions specified by this AD are intended to detect and correct damage to the engine exhaust mufflers caused by such high stress and cracking, which could result in exhaust gases entering the airplane cabin with consequent crew and passenger injury.

Final rule; request for comments.

98-13-10 CESSNA AIRCRAFT COMPANY: Amendment 39-10598; Docket No. 98-CE-59-AD.

Applicability: Model 182S airplanes, all serial numbers, certificated in any category.

NOTE 1: This AD applies to each airplane 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 airplanes that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (e) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.

Compliance: Required as indicated in the body of this AD, unless already accomplished.

To detect and correct damage to the engine exhaust mufflers caused by high stresses imposed on the attachment of the exhaust at the area of the firewall and cracking, which could result in exhaust gases entering the airplane cabin with consequent crew and passenger injury, accomplish the following:

(a) Within the next 5 days after the effective date of this AD, accomplish the following:

(1) Fabricate a placard that specifies immediately inspecting all engine exhaust muffler end plates when the engine backfires upon start-up, and install this placard on the instrument panel within the pilot's clear view. The placard should utilize letters of at least 0.10-inch in height and contain the following words: "If the engine backfires upon start-up, prior to further flight, inspect and replace (as necessary) all engine exhaust muffler end plates in accordance with AD 98-13-10. "

(2) Insert a copy of this AD into the Limitations Section of the airplane flight manual(AFM).

(b) Within the next 25 hours time-in-service (TIS) after the effective date of this AD and thereafter at intervals not to exceed 25 hours TIS after the previous inspection (including any inspection accomplished after an engine backfire), inspect all engine exhaust muffler end plates (four total) for cracks on the forward (upstream) or aft (downstream) end of each muffler can. Prior to further flight, replace any engine exhaust muffler where an end plate is found cracked. The replacement does not eliminate the repetitive inspection requirement of this AD.

NOTE 2: Cessna Service Bulletin SB98-78-02, Issued: June 6, 1998, depicts the area to be inspected. The actions of this service bulletin are different from those required by this AD. This AD takes precedence over the actions specified in the service bulletin, and accomplishment of the service bulletin is not considered an alternative method of compliance to the actions of this AD. Copies of this service bulletinmay be obtained from the Cessna Aircraft Company, Product Support, P.O. Box 7706, Wichita, Kansas 67277.

(c) Fabricating and installing the placard and inserting this AD into the Limitations Section of the AFM, as required by paragraph (a) of this AD, may be performed by the owner/operator holding at least a private pilot certificate as authorized by section 43.7 of the Federal Aviation Regulations (14 CFR 43.7), and must be entered into the aircraft records showing compliance with this AD in accordance with section 43.9 of the Federal Aviation Regulations (14 CFR 43.9).

(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 airplane to a location where the requirements of this AD can be accomplished.

(e) An alternative method of compliance or adjustment of the compliance time that provides an equivalent level of safety may be approved by the Manager, Wichita Aircraft Certification Office (ACO), 1801 Airport Road, Room 100, Mid-Continent Airport, Wichita, Kansas 67209. The request shall be forwarded through an appropriate FAA Maintenance Inspector, who may add comments and then send it to the Manager, Wichita ACO.

NOTE 3: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Wichita ACO.

(f) Information related to this AD may be examined at the FAA, Central Region, Office of the Regional Counsel, Room 1558, 601 E. 12th Street, Kansas City, Missouri.

(g) This amendment becomes effective on July 8, 1998.

Discussion
The FAA has received reports of incidents where cracks were found in an engine exhaust muffler end plate on several Cessna Model 182S airplanes. These cracks were caused by high stresses imposed on the attachment of the exhaust at the area of the firewall.

The design of the Cessna Model 182S airplanes is such that, during start-up, the engine could backfire and high stresses could then be imposed on the attachment of the exhaust at the area of the firewall. These high stresses cause cracks in the engine exhaust muffler end plates.

The FAA's Determination
After examining the circumstances and reviewing all available information related to the incidents described above, the FAA has determined that AD action should be taken to detect and correct damage to the engine exhaust mufflers caused by such high stress and cracking, which could result in exhaust gases entering the airplane cabin with consequent crew and passenger injury.Explanation of the Provisions of the AD
Since an unsafe condition has been identified that is likely to exist or develop in other Cessna Model 182S airplanes of the same type design, the FAA is issuing an AD. This AD requires repetitively inspecting all engine exhaust muffler end plates (four total) for cracks and replacing any muffler where an end plate is found cracked. The AD also requires fabricating and installing a placard that specifies immediately inspecting all engine exhaust muffler end plates any time the engine backfires upon start-up.

Compliance Time of This AD
The compliance time of the placard requirements of this AD is presented in calendar time instead of hours time-in-service. The chance of the engine backfiring upon start-up is the same for airplanes with 25 hours TIS as it is for airplanes with 100 hours TIS. Therefore, to assure that the engine exhaust muffler end plates are inspected any time the engine backfires upon start-up on all of the affected airplanes, a compliance based upon calendar time is utilized.

Determination of the Effective Date of the AD
Since a situation exists (possible engine exhaust system damage and exhaust gases entering the airplane cabin with consequent crew and passenger injury) that requires the immediate adoption of this regulation, it is found that notice and opportunity for public prior 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 immediate flight safety and, thus, was not preceded by notice and opportunity to 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 above. 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 rule must submit a self-addressed, stamped postcard on which the following statement is made: "Comments to Docket No. 98-CE-59-AD." The postcard will be date stamped and returned to the commenter.

Regulatory Impact
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 (otherwise, an evaluation is not required). A copy of it, if filed, may be obtained from the Rules Docket.

List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, 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), 40113, 44701. 39.13 [Amended]
2. Section 39.13 is amended by adding a new airworthiness directive (AD) to read as follows: