E8-7258. Airworthiness Directives; Cessna Aircraft Company Models 175 and 175A Airplanes

AGENCY:

Federal Aviation Administration (FAA), Department of Transportation (DOT).

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

We propose to adopt a new airworthiness directive (AD) for certain Cessna Aircraft Company (Cessna) Models 175 and 175A airplanes. This proposed AD would require you to check the airplane logbook to determine if the original engine mounting brackets have been replaced. If the original engine mounting brackets are still installed, this proposed AD would require you to repetitively inspect those brackets for cracks and replace any cracked engine mounting bracket. After replacing all four original engine mounting brackets, no further action would be required by this proposed AD. This proposed AD was prompted by a report that the engine became detached from the firewall during landing on one of the affected airplanes. We are proposing this AD to detect and correct cracks in the engine mounting brackets, which could result in failure of the engine mounting bracket. This failure could lead to the engine detaching from the firewall.

DATES:

We must receive comments on this proposed AD by June 9, 2008.

ADDRESSES:

Use one of the following addresses to comment on this proposed AD:

• DOT Docket Web site: Go to http://dms.dot.gov and follow the instructions for sending your comments electronically.
• Mail: U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue, SE., Washington, DC 20590.
• Fax: [phone].
• Hand Delivery: U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue, SE., Washington, DC 20590, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.
• Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.

For service information identified in this proposed AD, contact Cessna Aircraft Company, Product Support, P.O. Box 7706, Wichita, Kansas 67277; telephone: [phone]; fax: [phone].

FOR FURTHER INFORMATION CONTACT:

Gary Park, Aerospace Engineer, FAA, Wichita Aircraft Certification Office, 1801 Airport Road, Room 100, Wichita, Kansas 67209; telephone: [phone]; fax: [phone]; e-mail address: [e-mail].

SUPPLEMENTARY INFORMATION:

Comments Invited

We invite you to send any written relevant data, views, or arguments regarding this proposed AD. Send your comments to an address listed under the ADDRESSES section. Include the docket number, “FAA-2007-29240; Directorate Identifier 2007-CE-076-AD” at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of the proposed AD. We will consider all comments received by the closing date and may amend the proposed AD in light of those comments.

We will post all comments we receive, without change, to http://dms.dot.gov, including any personal information you provide. We will also post a report summarizing each substantive verbal contact we receive concerning this proposed AD.

Discussion

We received a report of the engine detaching from the firewall on a Cessna Model 175 airplane during landing. Investigation revealed that cracks in the two top engine mounting brackets behind the firewall caused the brackets to fail. This resulted in the top half of the firewall failing, pulling forward and down about 18 inches.

The National Transportation Safety Board (NTSB) Materials Laboratory examined the cracked brackets. The examination revealed that the metal content of the brackets did not contain the constituent elements of the specified material and was approximately 40 percent below the specified strength. The NTSB determined that reduced structural integrity of the engine mounting brackets resulted in fatigue cracks developing in the brackets.

We agree with the NTSB's determination that inadequate materials used in manufacturing the engine mounting brackets, which were used on Cessna Models 175 and 175A airplanes manufactured from 1958 through 1960, caused the engine mounting brackets to crack.

This condition, if not corrected, could cause the engine mounting brackets to fail. This failure could result in the engine detaching from the firewall.

Relevant Service Information

We have reviewed Cessna Single Engine Service Bulletin SEB07-2, Revision 2, dated June 18, 2007. The service information describes procedures for:

• Inspecting the upper and lower engine mounting brackets on both the left and right sides for cracks; and
• Replacing cracked engine mounting brackets.

FAA's Determination and Requirements of the Proposed AD

We are proposing this AD because we evaluated all information and determined the unsafe condition described previously is likely to exist or develop on other products of the same type design. This proposed AD would require you to check the airplane logbook to determine if the original engine mounting brackets have been replaced. If the original engine mounting brackets are still installed, this proposed AD would require you to repetitively inspect those brackets for cracks and replace any cracked engine mounting bracket. After replacing all four original engine mounting brackets, no further action would be required by this proposed AD. This proposed AD would require you to use the service information described previously to perform these actions.

Costs of Compliance

We estimate that this proposed AD would affect 1,218 airplanes in the U.S. registry.

We estimate the following costs to do each proposed inspection:

Labor cost	Parts cost	Total cost per airplane	Total cost on U.S. operators
7.5 work-hours × $80 per hour = $600	Not applicable	$600	$730,800

We estimate the following costs to do the proposed replacements.

Labor cost	Parts cost	Total cost per airplane
3 work-hours per bracket × $80 per hour = $240 per bracket. 4 brackets per airplane × $240 per bracket = $960	$200 per bracket. 4 × $200 = $800 for all 4 brackets	$440 per bracket. $1,760 to replace all 4 brackets.

Authority for This Rulemaking

Title 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety. Subtitle I, Section 106, describes the authority of the FAA Administrator. Subtitle VII, Aviation Programs, describes in more detail the scope of the Agency's authority.

We are issuing this rulemaking under the authority described in Subtitle VII, Part A, Subpart III, Section 44701, “General requirements.” Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action.

Regulatory Findings

We have determined that this proposed AD would not have federalism implications under Executive Order 13132. This proposed AD would not have a substantial direct effect 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.

For the reasons discussed above, I certify that the 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. 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.

We prepared a regulatory evaluation of the estimated costs to comply with this proposed AD and placed it in the AD docket.

Examining the AD Docket

You may examine the AD docket that contains the proposed AD, the regulatory evaluation, any comments received, and other information on the Internet at http://dms.dot.gov; or in person at the Docket Management Facility between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The Docket Office (telephone [phone]) is located at the street address stated in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Safety

The Proposed Amendment

Accordingly, under the authority delegated to me by the Administrator, the FAA proposes to amend 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. The FAA amends § 39.13 by adding the following new AD:

Cessna Aircraft Company: Docket No. FAA-2007-29240; Directorate Identifier 2007-CE-076-AD.

Comments Due Date

(a) We must receive comments on this airworthiness directive (AD) action by June 9, 2008.

Affected ADs

(b) None.

Applicability

(c) This AD applies to the following airplane models and serial numbers that are certificated in any category:

Model	Serial Nos.	Year manufactured
(1) 175	55001 through 55703	1958.
(2) 175	55704 through 56238	1959.
(3) 175	28700A, 626, and 640	1958 and 1959.
(4) 175A	691, and 56239 through 56777	1960.

Unsafe Condition

(d) A report that the engine became unattached from the firewall during landing on one of the affected airplanes prompts this AD. We are issuing this AD to detect and correct cracks in the engine mounting brackets, which could result in failure of the engine mounting bracket. This failure could lead to the engine detaching from the firewall.

Compliance

(e) To address this problem, you must do the following, unless already done:

Actions	Compliance	Procedures
(1) Check the airplane logbook to determine if all four of the original engine mounting brackets have been replaced.	Within the next 30 days after the effective date of this AD	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) may do this action.
(2) If you can positively determine that all four of the original engine mounting brackets have been replaced, no further action is required.	Not applicable	Make an entry into the aircraft logbook showing compliance with this portion of the AD in accordance with section 43.9 of the Federal Aviation Regulations (14 CFR 43.9). 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) may do this action.
(3) If you cannot positively determine that all four of the original engine mounting brackets have been replaced, inspect each of the upper and lower engine mounting brackets on both the left and right sides for cracks as specified in the service bulletin.	Initially inspect within the next 12 months after the effective date of this AD. If no cracks are found, repetitively inspect thereafter at intervals not to exceed 500 hours time-in-service (TIS) until all four of the original engine mounting brackets are replaced	Follow Cessna Single Engine Service Bulletin SEB07-2, Revision 2, dated June 18, 2007.
(4) If cracks are found in any of the engine mounting brackets during any inspection required in paragraph (e)(3) of this AD, replace the cracked engine mounting bracket(s).	Before further flight after the inspection in which cracks are found. Replacing the cracked engine mounting bracket terminates the repetitive inspection required in paragraph (e)(3) of this AD only for the replaced engine mounting bracket	Follow Cessna Single Engine Service Bulletin SEB07-2, Revision 2, dated June 18, 2007.
(5) To terminate the repetitive inspections required in paragraph (e)(3) of this AD, you may replace all four original engine mounting brackets.	At any time before or after the initial inspection required in paragraph (e)(3) of this AD	Follow Cessna Single Engine Service Bulletin SEB07-2, Revision 2, dated June 18, 2007.
(6) Dispose of every replaced bracket following 14 CFR 43.10, paragraph (c)(6), which states the following: “Mutilation. The part may be mutilated to deter its installation in a type certificated product. The mutilation must render the part beyond repair and incapable of being reworked to appear to be airworthy.”	Before further flight after the engine mounting bracket is removed for replacement	Not applicable.

Alternative Methods of Compliance (AMOCs)

(f) The Manager, Wichita Aircraft Certification Office (ACO), FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. Send information to ATTN: Gary Park, Aerospace Engineer, FAA, Wichita ACO, 1801 Airport Road, Room 100, Wichita, Kansas 67209; telephone: [phone]; fax: [phone]; e-mail address: [e-mail]. Before using any approved AMOC on any airplane to which the AMOC applies, notify your appropriate principal inspector (PI) in the FAA Flight Standards District Office (FSDO), or lacking a PI, your local FSDO.

Related Information

(g) To get copies of the service information referenced in this AD, contact Cessna Aircraft Company, Product Support, P.O. Box 7706, Wichita, Kansas 67277; telephone: [phone]; fax: [phone]. To view the AD docket, go to U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue, SE., Washington, DC 20590, or on the Internet at http://dms.dot.gov. The docket number is Docket No. FAA-2007-29240; Directorate Identifier 2007-CE-076-AD.

Issued in Kansas City, Missouri, on March 31, 2008.

Kim Smith,

Manager, Small Airplane Directorate, Aircraft Certification Service.