2010-27460. Airworthiness Directives; Cessna Aircraft Company (Cessna) Model 402C Airplanes Modified by Supplemental Type Certificate (STC) SA927NW and Model 414A Airplanes Modified by STC SA892NW

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

We propose to adopt a new airworthiness directive (AD) for the products listed above. This proposed AD would require a complete inspection of the flap system and modification of the flap control system. This proposed AD was prompted by a report of a Cessna Model 414A airplane modified by STC SA892NW that experienced an asymmetrical flap condition causing an un-commanded roll when the pilot set the flaps to the approach position. We are proposing this AD to prevent failure of the flap system, which could result in an asymmetrical flap condition. This condition could result in loss of control.

DATES:

We must receive comments on this proposed AD by December 13, 2010.

ADDRESSES:

You may send comments by any of the following methods:

• Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.
• Fax: [phone].
• 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.
• Hand Delivery: Deliver to Mail address above between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

For service information identified in this proposed AD, contact Sierra Industries, Ltd., 122 Howard Langford Drive, Uvalde, Texas 78801; telephone: [phone]; e-mail: [e-mail]; Internet: http://www.sijet.com. You may review copies of the referenced service information at the FAA, Small Airplane Directorate, 901 Locust, Kansas City, Missouri 64106. For information on the availability of this material at the FAA, call 816-329-4148.

Examining the AD Docket

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

FOR FURTHER INFORMATION CONTACT:

Werner Koch, Aerospace Engineer, Fort Worth Airplane Certification Office, FAA, 2601 Meacham Blvd., Fort Worth, Texas 76137; phone: [phone]; fax: [phone]; e-mail: [e-mail].

SUPPLEMENTARY INFORMATION:

Comments Invited

We invite you to send any written relevant data, views, or arguments about this proposal. Send your comments to an address listed under the ADDRESSES section. Include “Docket No. FAA-2010-1084; Directorate Identifier 2010-CE-056-AD” at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this proposed AD. We will consider all comments received by the closing date and may amend this proposed AD because of those comments.

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

Discussion

We received a report of a Cessna Model 414 airplane, modified by Sierra Industries, Ltd., STC SA892NW (formerly held by Robertson Aircraft Corporation) that experienced an asymmetrical flap condition causing an un-commanded roll when the pilot set the flaps to the approach position. The flap preselect cable connects to the arm assembly and provides the flap position to the flap selector to close the position loop for the flap position. Micro switches are located on the arm assembly and provide the electrical signal for the arm position.

STC SA927NW and STC SA892NW use the original production preselect cable. However, the STCs added an extension to the arm assembly that requires increased travel of the preselect cable to obtain the same rotation as previously obtained with the shorter arm assembly. To obtain the same arm assembly rotation, the preselect cable must travel approximately an additional .75 inch. However, the original cable has internal mechanical stops that prevent it from traveling the additional distance. The cable's internal stops are contacted by a smaller rotation displacement of the arm assembly. Since more linear displacement of the cable is required to obtain the same switch action, the internal mechanical stops of the cable are reached before the switches designed to stop the motion of the flaps activate.

As a result, when the internal stops in the cable are contacted, the rotation of the arm assembly carrying the micro switches stops and the switch to stop the drive motor is not activated. Because the switch is not activated, the motor continues to run until either the motor drive shear pin fails, a cable breaks, the structural bracket breaks, or the secondary switches stop the motor before something breaks. The sequence was verified on the reported airplane by the rigging, installation, and operation of an STC production configuration.

This condition, if not corrected, could result in an asymmetrical flap condition. This failure could lead to loss of control.

Relevant Service Information

We reviewed Sierra Industries, Ltd. Service Bulletin SI09-82 Series-1, Rev. IR, dated September 8, 2010. The service information describes procedures for inspecting the flap system, installing a new preselect cable with increased internal stroke, making additional component modifications, and installing and rigging the flap control system.

FAA's Determination

We are proposing this AD because we evaluated all the relevant information and determined the unsafe condition described previously is likely to exist or develop in other products of the same type design.

Proposed AD Requirements

This proposed AD would require accomplishing the actions specified in the service information described previously.

Costs of Compliance

We estimate that this proposed AD affects 150 airplanes of U.S. registry.

We estimate the following costs to comply with this proposed AD:

Estimated Costs

Action	Labor cost	Parts cost	Cost per product	Cost on U.S. operators
Inspect the flap system and modify/replace the flap preselect control cable	20 work-hours × $85 per hour = $1,700	$1,000	$2,700	$405,000

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 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 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),

(3) Will not affect intrastate aviation in Alaska, and

(4) 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.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Incorporation by reference
• 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 airworthiness directive (AD):

Cessna Aircraft Company: Docket No. FAA-2010-1084; Directorate Identifier 2010-CE-056-AD.

Comments Due Date

(a) We must receive comments by December 13, 2010.

Affected ADs

(b) None.

Applicability

(c) This AD applies to Cessna Aircraft Company (Cessna) Model 402C airplanes modified by Supplemental Type Certificate (STC) SA927NW and Model 414A airplanes modified by STC SA892NW, all serial numbers, that are certificated in any category.

Subject

(d) Joint Aircraft System Component (JASC)/Air Transport Association (ATA) of America Code 57, Wings.

Unsafe Condition

(e) This AD was prompted by a report of a Cessna Model 414A airplane modified by STC SA892NW that experienced an asymmetrical flap condition causing an un-commanded roll when the pilot set the flaps to the approach position. We are issuing this AD to prevent failure of the flap system, which could result in an asymmetrical flap condition. This condition could result in loss of control.

Compliance

(f) Comply with this AD within the compliance times specified, unless already done.

Required Actions

(g) Within 60 days after the effective date of this AD, do a complete inspection of the flap system following the Inspection Instructions section of Sierra Industries, Ltd. Service Bulletin SI09-82 Series-1, Rev. IR, dated September 8, 2010.

(h) Before further flight after the inspection required in paragraph (g) of this AD where any damage to the flap bellcrank or bellcrank mounting structure is found, repair the damage and modify the flap control system following the Accomplishment Instructions of Sierra Industries, Ltd. Service Bulletin SI09-82 Series-1, Rev. IR, dated September 8, 2010.

(i) Within 180 days after the effective date of this AD where damage to the flap bellcrank or bellcrank mounting structure is not found during the inspection required in paragraph (g) of the AD, modify the flap control system following the Accomplishment Instructions of Sierra Industries, Ltd. Service Bulletin SI09-82 Series-1, Rev. IR, dated September 8, 2010.

Alternative Methods of Compliance (AMOCs)

(j)(1) The Manager, Fort Worth Airplane Certification Office, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. In accordance with 14 CFR 39.19, send your request to your principal inspector or local Flight Standards District Office, as appropriate. If sending information directly to the manager of the ACO, send it to the attention of the person identified in the Related Information section of this AD.

(2) Before using any approved AMOC, notify your Principal Maintenance Inspector or Principal Avionics Inspector, as appropriate, or lacking a principal inspector, your local Flight Standards District Office.

Related Information

(k) For more information about this AD, contact Werner Koch, Aerospace Engineer, Fort Worth Airplane Certification Office, FAA, 2601 Meacham Blvd., Fort Worth, Texas 76137; phone: [phone]; fax: [phone]; e-mail: [e-mail].

(l) For service information identified in this AD, contact Sierra Industries, Ltd., 122 Howard Langford Drive, Uvalde, Texas 78801; telephone: [phone]; e-mail: [e-mail]; Internet: http://www.sijet.com. You may review copies of the referenced service information at the FAA, Small Airplane Directorate, 901 Locust, Kansas City, Missouri 64106. For information on the availability of this material at the FAA, call 816-329-4148.

Issued in Kansas City, Missouri, on October 25, 2010.

John Colomy,

Acting Manager, Small Airplane Directorate, Aircraft Certification Service.