2010-31960. Airworthiness Directives; Kaman Aerospace Corporation (Kaman) Model K-1200 Helicopters

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Final rule; request for comments.

SUMMARY:

We are adopting a new airworthiness directive (AD) for the Kaman Model K-1200 helicopters. This AD requires revising the Limitations section of the Instructions for Continued Airworthiness (ICA) by establishing a life limit of 8,000 hours time-in-service (TIS) for each main rotor blade (blade) set. Also, this AD requires removing each blade set from service if it has accumulated 8,000 or more hours time-in-service (TIS). This AD also requires replacing certain blade sets with airworthy blade sets at specified intervals based on the blade set serial number (S/N). This AD was prompted by an accident and the subsequent discovery of cracks in multiple blade spars. We are issuing this AD to prevent blade failure and subsequent loss of control of the helicopter.

DATES:

This AD is effective on January 5, 2011.

We must receive comments on this AD by February 22, 2011.

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: 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.

For service information identified in this AD, contact Kaman Aerospace Corporation, K-max Product Support Center, Building 33, P.O. Box 2, 1332 Blue Hills Avenue, Bloomfield, CT 06002, telephone [phone].

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 AD, the regulatory evaluation, any comments received, and other information. The street address for the Docket Office (telephone: [phone]) is in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt. You may review copies of the referenced service information at the FAA, Rotorcraft Directorate, 2601 Meacham Boulevard, Fort Worth, TX 76137.

FOR FURTHER INFORMATION CONTACT:

Nicholas Faust, Aerospace Engineer, Boston Aircraft Certification Office, FAA, 12 New England Executive Park; telephone: [phone]; fax: [phone]; e-mail: [e-mail].

SUPPLEMENTARY INFORMATION:

Discussion

We are adopting a new AD for the Kaman Model K-1200 helicopters that requires revising the Airworthiness Limitations section of the ICA by establishing a life limit of 8,000 hours TIS for each blade set. Previously, these blades sets did not have an established retirement life but had specified overhaul intervals. This AD also requires removing each blade set with 8,000 or more hours TIS from service. Also, this AD requires replacing certain blade sets with airworthy blade sets at specified intervals based on the blade set S/N. This AD was prompted by an accident and the subsequent discovery of cracks in multiple blade spars. This condition, if not corrected, could result in a cracked spar, failure of a blade, and subsequent loss of control of the helicopter.

Relevant Service Information

We reviewed Kaman Service Bulletin No. 131, Rotor Blade Service Life Reduction, dated August 11, 2010 (SB). The SB specifies establishing “a service life of K-1200 rotor blade spar bondment (K911004) to 8,000 hours time since new (TSN)” and removing all blade sets with over 8,000 hours TIS.

FAA's Determination

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

AD Requirements

This AD requires, before further flight, revising the Airworthiness Limitations section of the ICA by establishing a life limit of 8,000 hours TIS for each affected blade set. This AD requires replacing the specified blade sets with airworthy blade sets at various intervals depending on TIS. Based on the individualized data from those operators with the affected serial-numbered blade sets, those serial numbered blade sets with the highest hours TIS are required to be replaced sooner than those with less hours TIS.

Differences Between the AD and the Service Information

This AD requires, before further flight, revising the Airworthiness Limitations section of the ICA to establish a life limit of 8,000 hours TIS for each blade set. Also, this AD requires replacing certain blade sets with airworthy blade sets at specified intervals based on the blade S/N.

FAA's Justification and Determination of the Effective Date

An unsafe condition exists that requires the immediate adoption of this AD. The FAA finds that the risk to the flying public justifies waiving notice and comment prior to adopting this rule because cracks have been found in the blade spars during an investigation in response to an accident. Due to the number of hours TIS of the fleet, some of the blade sets may have exceeded 8,000 hours TIS and the blade sets may be required to be replaced before further flight. Therefore, we find that notice and opportunity for prior public comment are impracticable and that good cause exists for making this amendment effective in less than 30 days.

Comments Invited

This AD is a final rule that involves requirements affecting flight safety and was not preceded by notice and an opportunity for public comment. However, we invite you to send any written data, views, or arguments about this AD. Send your comments to an address listed under the ADDRESSES section. Include the docket number FAA-2010-1253 and Directorate Identifier 2010-SW-084-AD at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this AD. We will consider all comments received by the closing date and may amend this 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 AD.

Costs of Compliance

We estimate that this AD affects 14 helicopters of U.S. registry. The Kaman Model K-1200 helicopter is unique in that each helicopter has 2 sets of 2 blades, a total of 4 blades per helicopter. Some helicopters only require one set of blades to be replaced.

We estimate the following costs to comply with this AD:

Estimated Costs

Action	Labor cost	Parts cost	Cost per helicopter	Cost on U.S. operators
Replace blade set (2 blades)	4 work-hours × $85 per hour = $340 per blade set	$198,751 per blade set	$199,091 per blade set	$1,393,637, assuming 7 blade sets are replaced.

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 helicopters identified in this rulemaking action.

Regulatory Findings

This AD will not have federalism implications under Executive Order 13132. This AD will 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 this AD:

(1) Is not a “significant regulatory action” under Executive Order 12866,

(2) Is not a “significant rule” under 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
• Safety

Adoption of the Amendment

Accordingly, under the authority delegated to me by the Administrator, the FAA amends 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):

2010-26-11 Kaman Aerospace Corporation: Amendment 39-16550; Docket No. FAA-2010-1253; Directorate Identifier 2010-SW-084-AD.

Effective Date

(a) This AD is effective on January 5, 2011.

Other Affected ADs

(b) None.

Applicability

(c) This AD applies to Model K-1200 helicopters.

Unsafe Condition

(d) This AD was prompted by an accident and the subsequent discovery of cracks in the main rotor blade (blade) spars. We are issuing this AD to prevent blade failure and subsequent loss of control of the helicopter.

Compliance

(e) Before further flight, unless already done:

(1) Revise the Limitations section of the Instructions for Continued Airworthiness by establishing a life limit of 8,000 hours time-in-service (TIS) for each blade set Remove each blade set with 8,000 or more hours TIS.

(2) Replace each specified serial-numbered blade set with an airworthy blade set in accordance with the following table:

Blade-set Serial No.	Replace within
101, 403, 408, 409, 411, and 415	400 hours TIS.
417 and 419	700 hours TIS.
405	1000 hours TIS.

Subject

(f) Joint Aircraft System Component (JASC)/Air Transport Association (ATA) of America Code: 6210 Main Rotor Blades.

Alternative Methods of Compliance (AMOCs)

(g) The Manager, Boston Aircraft 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 “Additional Information” section of this AD.

Note:

Before using any approved AMOC, we request that you notify your principal inspector or if you have no principal inspector, your local Flight Standards District Office.

Additional Information

(h) For more information about this AD, contact Nicholas Faust, Aerospace Engineer, Boston Aircraft Certification Office, FAA, 12 New England Executive Park; telephone: [phone]; fax: [phone]; e-mail: [e-mail].

Issued in Fort Worth, Texas, on December 14, 2010.

Bruce Cain,

Acting Manager, Rotorcraft Directorate, Aircraft Certification Service.