03-20983. Airworthiness Directives; Short Brothers and Harland Ltd. Models SC-7 Series 2 and SC-7 Series 3 Airplanes

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Final rule.

SUMMARY:

This amendment adopts a new airworthiness directive (AD) that applies to all Short Brothers and Harland Ltd. (Shorts) Models SC-7 Series 2 and SC-7 Series 3 airplanes. This AD establishes a technical service life for these airplanes and allows you to incorporate modifications, inspections, and replacements of certain life limited items to extend the life limits of these airplanes. This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for the United Kingdom. The actions specified by this AD are intended to prevent failure of critical structure of the aircraft caused by fatigue.

DATES:

This AD becomes effective on September 29, 2003.

The Director of the Federal Register approved the incorporation by reference of certain publications listed in the regulations as of September 29, 2003.

ADDRESSES:

You may get the service information referenced in this AD from Short Brothers PLC, PO Box 241, Airport Road, Belfast BT3 9DZ Northern Ireland; telephone: [phone]; facsimile: [phone]. You may view this information at the Federal Aviation Administration (FAA), Central Region, Office of the Regional Counsel, Attention: Rules Docket No. 2000-CE-17-AD, 901 Locust, Room 506, Kansas City, Missouri 64106; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT:

Doug Rudolph, Aerospace Engineer, FAA, Small Airplane Directorate, 901 Locust, Room 301, Kansas City, Missouri 64106; telephone: [phone]; facsimile: [phone].

SUPPLEMENTARY INFORMATION:

Discussion

What events have caused this AD? The Civil Aviation Authority (CAA), which is the airworthiness authority for the United Kingdom, recently notified FAA that an unsafe condition may exist on all Shorts Models SC-7 Series 2 and SC-7 Series 3 airplanes. The CAA reports that the Model SC-7 airframe has undergone structural evaluations that have resulted in the establishment of an airplane service life limit.

Modifications, inspections, and replacements of certain life limited items have been identified to further extend the life of the aircraft.

What is the potential impact if FAA took no action? The life limits, if not complied with, could result in failure of the primary structural components and possibly result in structural failure during flight.

Has FAA taken any action to this point? We issued a proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an AD that would apply to all Shorts Models SC-7 Series 2 and SC-7 Series 3 airplanes. This proposal was published in the Federal Register as a notice of proposed rulemaking (NPRM) on November 13, 2002 (67 FR 68779). The NPRM proposed to establish a technical service life for these airplanes and allow you to incorporate modifications, inspections, and replacements of certain life limited items to extend the life limits of these airplanes.

Was the public invited to comment? The FAA encouraged interested persons to participate in the making of this amendment. The following presents the comments received on the proposal and FAA's response to each comment:

Comment Issue No. 1: AD Is Not Needed

What is the commenter's concern? One commenter states that the proposed issuance of this AD serves no safety benefit since all of the U.S. registered airplanes affected are already in compliance with the referenced service information, and no accidents have been reported as a result of any structural failures. The commenter recommends that FAA not issue this AD. We infer that the commenter recommends that FAA withdraw the NPRM.

What is FAA's response to the concern? We do not concur that the AD serves no safety benefit and that we should withdraw the NPRM. The FAA does not have confirmation that all of the U.S. registered airplanes are in compliance with the referenced service information. In addition, imported aircraft need to have the AD stated for a records checks during issuance of an airworthiness certificate. The actions referenced in the service information are not required when the service life limits are reached, unless required by AD.

Therefore, the AD is necessary to ensure the life limits are required. We are not changing the final rule AD action as a result of this comment.

Comment Issue No. 2: Economic Hardship

What is the commenter's concern? Ten commenters state that issuing the AD would result in economic hardship to them. Specifically, these commenters communicated the following:

—Seven commenters state that issuing the AD would result in a prohibitive cost increase for their use of the aircraft or result in the loss of the aircraft. We infer that “by loss of the use of the aircraft” that the owner/operator of the affected airplane would choose to retire the airplane from service.

—Three commenters state that issuing the AD would reduce the remaining time-in-service of the affected airplanes and result in airplanes with no resale value. We infer that owners/operators would choose to withdraw airplanes from service rather than work with the manufacturer to develop a life extension program for the affected airplanes.

We infer that the 10 commenters want FAA to withdraw the NPRM.

What is FAA's response to the concern? The FAA does not concur that the NPRM should be withdrawn because of economic impact. We have no way of determining the number or extent of inspections, repairs, and replacements that would be necessary based on the owner/operator and manufacturer developed life extension program for the affected airplanes noted in the NPRM. Further, it is the owners'/operators' responsibility to propose an alternative method of compliance that provides an acceptable level of safety.

We are not changing the final rule AD action as a result of theses comments.

Comment Issue No. 3: Insufficient Comment Time

What is the commenter's concern? Five commenters state that the comment period length was insufficient, that additional time is necessary to obtain technical information from the manufacturer, that there is no urgent safety condition indicating the need for this AD, and that more time is needed to propose a more comprehensive inspection program.

We infer that the five commenters want FAA to extend the comment period of the NPRM and delay issuance of the AD.

What is FAA's response to the concern? We disagree that the comment period for the NPRM should be extended. The comment period ended on December 23, 2002. However, FAA has always accepted late comments. Based on the timing of the final rule, the public had more than six extra months to comment on the NPRM. The FAA agrees that no urgent safety of flight condition existed; if an urgent safety of flight condition exists for this type design, we would have determined that this regulation is an emergency regulation that must be issued immediately and that must become effective prior to public comment. Owners/operators who want to propose a more comprehensive inspection program are free to work with the manufacturer to develop a life extension program for the affected airplane(s) and submit a plan to the FAA as an alternative method of compliance.

We are not changing the final rule AD action as a result of these comments.

Comment Issue No. 4: Inadequate/Incorrect Supporting Data

What is the commenter's concern? Six commenters state that inadequate/incorrect supporting data had been cited or used in the development of the NPRM, as follows:

—Several commenters state that FAA should require the manufacturer or others to submit data for review.

—Two commenters state that the aircraft's characteristics make it the most safe for their use. The FAA infers that the commenters prefer this type design to other type designs.

—Three commenters state that several airplanes have not been subject to operations that would reduce life limits. We infer that the commenters believe these airplanes are eligible for life extension programs.

What is FAA's response to the concern? The FAA disagrees that inadequate or incorrect supporting data has been considered in the development of the NPRM. Under the bilateral airworthiness agreement between the United Kingdom and the United States, the airworthiness authority (after coordination with the manufacturer), notified FAA that an unsafe condition exists or could develop on all Shorts Models SC-7 Series 2 and SC-7 Series 3 airplanes. The airworthiness authority reported that the Model SC-7 airframe has undergone structural evaluations that have resulted in the establishment of an airplane service life limit. Modifications, inspections, and replacements of certain life limited items were identified to further extend the life of the aircraft.

We have reviewed the available data and found the data adequate and correct. Therefore, we are not changing the final rule AD action as a result of these comments.

Comment Issue No. 5: Service Difficulty History Does Not Justify AD Action

What is the commenter's concern? Several commenters state that the service difficulty history shows no structural problems of the type stated in the NPRM. We infer that the commenters feel the lack of a service difficulty history for the type design warrants the withdrawal of the NPRM.

What is FAA's response to the concern? The FAA disagrees that the lack of a service difficulty history is sufficient to justify the withdrawal of the NPRM. The manufacturer and the airworthiness authority have stated that the life limit should be reduced based on their analyses and technical expertise.

The FAA has examined these findings, reviewed all available information, and determined that AD action should be taken. Therefore, we are not changing the final rule AD action as a result of these comments.

Comment Issue No. 6: Operational Profile (Gross Weight Penalty)

What is the commenter's concern? Two commenters state that certain airplanes have an operational history profile (operating at lesser gross weight than considered by the manufacturer and foreign airworthiness authority) that does not warrant reduction in life limits as would be required in the AD. The FAA infers that commenters want the withdrawal of the proposed NPRM or adjustment of the life limits for certain aircraft of the affected type design.

What is FAA's response to the concern? The FAA disagrees that certain airplanes' operational history profiles warrant withdrawal of the NPRM or changes in the life limits. The manufacturer and the foreign airworthiness authority have determined that AD action is needed, and FAA confirms this need for AD action.

The owners/operators of affected airplanes are free to work with the manufacturer to develop a life extension program for the affected airplanes and submit a plan to the FAA.

We are not changing the final rule AD action as a result of these comments.

Comment Issue No. 7: Safe Life Principle

What is the commenter's concern? The commenter states the argument that the manufacturer should not be using a 35-year old safe life process to determine life limits for aircraft of this type design. Further, newer non-destructive inspection (NDI) techniques are available. The FAA infers that the commenter wants the NPRM withdrawn or increased life limits for certain aircraft.

What is FAA's response to the concern? We disagree that the NPRM should be withdrawn or that there should be increased life limits for certain aircraft. Although newer NDI techniques do exist, no NDI procedures have been proposed for this issue that we have determined will detect the fatigue before it occurs. We will consider NDI procedures proposed as part of an alternative method of compliance.

We are not changing the final rule AD action as a result of this comment.

Comment Issue No. 8: Freedom of Information Act (FOIA) Request Not Fulfilled

What is the commenter's concern? One commenter states that FAA has not provided FOIA requested information. We infer that the commenter wants the NPRM withdrawn or a supplemental NPRM issued with the public allowed to review the requested information and to provide public comments with a new comment period.

What is FAA's response to the concern? The FAA disagrees that the NPRM should be withdrawn or a supplemental NPRM issued. The FAA handles FOIA requests independently of ADs. We have determined that an unsafe condition exists and that AD action is necessary to correct it.

Therefore, we are not changing the final rule AD action as a result of this comment.

Comment Issue No. 9: Service Bulletins Already Incorporated

What is the commenter's concern? Commenters state that all affected airplanes have incorporated the requirements of the referenced service information. Also, one service bulletin was issued in 1978. FAA infers that the commenters believe the NPRM should be withdrawn because they believe all airplanes in the United States have complied with the service information and the service bulletin issued in 1978 without a related AD action until now.

What is FAA's response to the concern? The FAA disagrees that the NPRM should be withdrawn. Assurance that all airplanes are in compliance with service information is not justification to not issue an AD. The original type certificate did not include service life limits. The only way to mandate these limits on all airplanes, including those getting future airworthiness certificates, is through AD action.

We are not changing the final rule AD action as a result of these comments.

Comment Issue No. 10: AD Action Should Not Apply to Aircraft Used in Part 91 Operations

What is the commenter's concern? The commenter states that, because the aircraft looks good and has been operated under favorable conditions, (1) there should be an in-depth study of the AD; (2) initial life limits for the aircraft should be 30,000 cycles; and (3) a recommended plan of inspection should be implemented. The FAA infers that the commenter wants the NPRM withdrawn or a supplemental NPRM issued with a life limit of 30,000 cycles and a recommended plan of inspection proposed.

What is FAA's response to the concern? We disagree that the NPRM should be withdrawn or a supplemental NPRM issued. We have determined that the AD as proposed addresses the unsafe condition. The referenced life extension program could be proposed as an alternative method of compliance provided details are included that show an acceptable level of safety. A detailed method and thresholds for cracks and inspection intervals would have to be proposed.

We are not changing the final rule AD action as a result of these comments.

FAA's Determination

What is FAA's final determination on this issue? After careful review of all available information related to the subject presented above, we have determined that air safety and the public interest require the adoption of the rule as proposed except for minor editorial corrections. We have determined that these minor corrections:

—Provide the intent that was proposed in the NPRM for correcting the unsafe condition; and

—Do not add any additional burden upon the public than was already proposed in the NPRM.

Cost Impact

How many airplanes does this AD impact? We estimate that this AD affects 22 airplanes in the U.S. registry.

What is the cost impact of this AD on owners/operators of the affected airplanes? The impact of this AD will be not being able to operate the airplane past the established service life limit. The following paragraphs present cost if you choose to extend the life limit.

We estimate the following costs to accomplish the aircraft life extension prescribed in Shorts Service Bulletin No. 51-51 on 19 aircraft:

Labor cost	Parts cost	Total cost per airplane	Total cost on U.S. operators
350 workhours × $60 per hour = $21,000	$90,000	$111,000	$2,109,000

We estimate the following to accomplish the aircraft life extension prescribed in Shorts Service Bulletin No. 51-52 for the 6 aircraft serial numbers 1845, 1847, 1883, 1889, 1943, and 1960:

Labor cost	Parts cost	Total cost per airplane	Total cost on U.S. operators
120 workhours × $60 per hour = $7,200	$22,000	$29,200	$175,200

Three of these 6 airplanes will also incorporate Shorts Service Bulletin No. 51-51 and are part of the 19 airplanes subset of the total set of 22 airplanes in the U.S. registry.

Compliance Time of This AD

What would be the compliance time of this AD? The compliance time of this AD is upon accumulating the applicable life limit or within the next 90 days after the effective date of this AD, whichever occurs later.

Why is the compliance time of this AD presented in flights, hours TIS and calendar time? The unsafe condition on these airplanes is a result of the combination of the number of times the airplane is operated and how the airplane is operated (for example, weight carried). Airplane operation varies among operators. For example, one operator may operate the airplane 100 flights or 50 hours TIS in 3 months and carrying low weights while it may take another operator 12 months or more to accumulate 100 flights or 50 hours TIS while carrying heavy weights. For this reason, we have determined that the compliance time of this AD will be specified in flights, hours time-in-service (TIS), and calendar time in order to assure this condition is not allowed to go uncorrected over time.

Regulatory Impact

Does this AD impact various entities? The regulations adopted herein 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. Therefore, it is determined that this final rule does not have federalism implications under Executive Order 13132.

Does this AD involve a significant rule or regulatory action? For the reasons discussed above, I certify that this action (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); 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. A copy of the final evaluation prepared for this action is contained in the Rules Docket. A copy of it may be obtained by contacting 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, under 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. FAA amends § 39.13 by adding a new AD to read as follows:

2003-17-05 Short Brothers and Harland Ltd.: Amendment 39-13279; Docket No. 2000-CE-17-AD.

(a) What airplanes are affected by this AD? This AD affects Models SC-7 Series 2 and SC-7 Series 3 airplanes, all serial numbers, that are certificated in any category.

(b) Who must comply with this AD? Anyone who wishes to operate any of the airplanes identified in paragraph (a) of this AD must comply with this AD.

(c) What problem does this AD address? The actions specified by this AD are intended to prevent failure of critical structure of the aircraft caused by fatigue.

(d) What must I do to comply with this AD? Do not operate the airplane upon accumulating the applicable life limit or within the next 90 days after September 29, 2003 (the effective date of this AD), whichever occurs later. The following table presents the life limits:

Serial number	Life limit
(1) SH1845 and SH1883	10,000 hours time-in-service (TIS).
(2) SH1847	15,200 hours TIS.
(3) SH1889	13,805 flights.
(4) SH1943	11,306 flights.
(5) SH1960	4,142 flights.
(6) All airplanes that do not have serial number SH1845, SH1883, SH1847, SH1889, SH1943, or SH1960	20,000 flights.

Note 1:

For owners/operators that do not have a record of the number of flights on the aircraft, assume the number of flights on the basis of two per operating hour.

(e) What must I do to extend the life limits for airplanes with serial number SH1845, SH1847, SH1883, SH1889, SH1943, or SH1960? To extend the life limit on one of these airplanes, you must accomplish the actions of Shorts Service Bulletin No. 51-52, Original Issue: September 1, 1981 (latest version at Revision No.: 4, dated: July 16, 2002), and Shorts Skyvan Maintenance Program 1, not dated. The following table presents the extended life limit:

Serial number	Extended life limit
(1) SH1845:	13,456 hours TIS.
(2) SH1847:	20,200 hours TIS.
(3) SH1883:	15,000 hours TIS.
(4) SH1889:	20,094 flights.
(5) SH1943:	17,325 flights.
(6) SH1960:	8,449 flights.

(f) What must I do to extend the life limit for my airplanes that do not have serial number SH1845, SH1883, SH1847, SH1889, SH1943, or SH1960? You can extend the life limit to 27,000 flights by accomplishing the actions of Shorts Service Bulletin No. 51-51, Original Issue: June 6, 1978 (latest version at Revision No.: 6, dated: March 14, 1983), and Shorts Skyvan Maintenance Program 1, not dated.

Note 2:

These life limits described in paragraph (e) are the final life limits of each aircraft unless the owner/operator works with Shorts Brothers PLC to develop a life extension program. Submit a plan to the FAA (address specified in paragraph (g) of this AD) for the proposed life extension program. Accomplishment of Shorts Service Bulletin No. 51-51, Original Issue: June 6, 1978 (latest version at Revision No.: 6, dated: March 14, 1983), does not extend the service life beyond the life limits described in paragraph (e).

(g) Can I comply with this AD in any other way? You may use an alternative method of compliance or adjust the compliance time if:

(1) Your alternative method of compliance provides an equivalent level of safety; and

(2) The Standards Office Manager, Small Airplane Directorate, approves your alternative. Submit your request through an FAA Principal Maintenance Inspector, who may add comments and then send it to the Standards Office Manager.

Note 3:

This AD applies to each airplane identified in paragraph (a) of this AD, 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 (g) 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 you have not eliminated the unsafe condition, specific actions you propose to address it.

(h) Where can I get information about any already-approved alternative methods of compliance? Contact Doug Rudolph, Aerospace Engineer, FAA, Small Airplane Directorate, 901 Locust, Room 301, Kansas City, Missouri 64106; telephone: [phone]; facsimile: [phone].

(i) What if I need to fly the airplane to another location to comply with this AD? The FAA can issue a special flight permit under sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate your airplane to a location where you can accomplish the requirements of this AD.

(j) Are any service bulletins incorporated into this AD by reference? Actions required by this AD must be done in accordance with Shorts Service Bulletin No. 51-51, Revision No.: 6, dated: March 14, 1983; and Shorts Service Bulletin No. 51-52, Revision No.: 4, dated: July 16, 2002). The Director of the Federal Register approved this incorporation by reference under 5 U.S.C. 552(a) and 1 CFR part 51. You may get copies from Short Brothers PLC, P.O. Box 241, Airport Road, Belfast BT3 9DZ Northern Ireland; telephone: [phone]; facsimile: [phone]. You may view copies at the FAA, Central Region, Office of the Regional Counsel, 901 Locust, Room 506, Kansas City, Missouri, or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

Note 4:

The subject of this AD is addressed in British AD Number 019-09-81, not dated.

(i) When does this amendment become effective? This amendment becomes effective on September 29, 2003.

Issued in Kansas City, Missouri, on August 12, 2003.

Diane K. Malone,

Acting Manager, Small Airplane Directorate, Aircraft Certification Service.