02-28751. Airworthiness Directives; Short Brothers and Harland Ltd. Models SC-7 Series 2 and SC-7 Series 3 Airplanes

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

This document proposes to adopt a new airworthiness directive (AD) that would apply to all Short Brothers and Harland Ltd. (Shorts) Models SC-7 Series 2 and SC-7 Series 3 airplanes. This proposed AD would 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. This proposed AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for the United Kingdom. The actions specified by this proposed AD are intended to prevent fatigue failure of critical structure of the aircraft. Such failure could result in reduced structural integrity of the aircraft with consequent failure of the primary structural components and possibly result in structural failure during flight.

DATES:

The Federal Aviation Administration (FAA) must receive any comments on this proposed rule on or before December 23, 2002.

ADDRESSES:

Submit comments to FAA, Central Region, Office of the Regional Counsel, Attention: Rules Docket No. 2000-CE-17-AD, 901 Locust, Room 506, Kansas City, Missouri 64106. You may view any comments at this location between 8 a.m. and 4 p.m., Monday through Friday, except Federal holidays. You may also send comments electronically to the following address: [e-mail]. Comments sent electronically must contain “Docket No. 2000-CE-17-AD” in the subject line. If you send comments electronically as attached electronic files, the files must be formatted in Microsoft Word 97 for Windows or ASCII text.

You may get service information that applies to this proposed AD from Short Brothers PLC, P.O. Box 241, Airport Road, Belfast BT3 9DZ Northern Ireland; telephone: [phone]; facsimile: [phone]. You may also view this information at the Rules Docket at the address above.

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:

Comments Invited

How Do I Comment on This Proposed AD?

The FAA invites comments on this proposed rule. You may submit whatever written data, views, or arguments you choose. You need to include the rule's docket number and submit your comments to the address specified under the caption ADDRESSES. We will consider all comments received on or before the closing date. We may amend this proposed rule in light of comments received. Factual information that supports your ideas and suggestions is extremely helpful in evaluating the effectiveness of this proposed AD action and determining whether we need to take additional rulemaking action.

Are There Any Specific Portions of This Proposed AD I Should Pay Attention to?

The FAA specifically invites comments on the overall regulatory, economic, environmental, and energy aspects of this proposed rule that might suggest a need to modify the rule. You may view all comments we receive before and after the closing date of the rule in the Rules Docket. We will file a report in the Rules Docket that summarizes each contact we have with the public that concerns the substantive parts of this proposed AD.

How Can I Be Sure FAA Receives My Comment?

If you want FAA to acknowledge the receipt of your mailed comments, you must include a self-addressed, stamped postcard. On the postcard, write “Comments to Docket No. 2000-CE-17-AD.” We will date stamp and mail the postcard back to you.

Discussion

What Events Have Caused This Proposed 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 Are the Consequences if the Condition Is Not Corrected?

The life limits, if not complied with, could result in failure of the primary structural components and possibly result in structural failure during flight.

Is There Service Information That Applies to This Subject?

Shorts has issued the following service information:

—Shorts Service Bulletin No. 51-51, Original Issue: June 6, 1978 (latest version at Revision No.: 6, dated: March 14, 1983);

—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.

What Are the Provisions of This Service Information?

Service information specifies procedures to be followed to allow life limits to be extended. They include:

—Reinforcing the webs of the stub wing front spar box;

—Replacing the side load fittings and doubler joint plates at the nose undercarriage lower attachment;

—Changing the shear angle attachments of the lift strut fitting to wing rib 212;

—Replacing the inner flap and outer flap components;

—Carrying out the life extension programs for the landing gear nose undercarriage and landing gear main undercarriage; and

—Carrying out the Skyvan Maintenance Program life extension inspection program.

What Action Did the CAA Take?

The CAA classified this service bulletin as mandatory and issued British AD Number 019-09-81, not dated, in order to ensure the continued airworthiness of these airplanes in the United Kingdom.

Was This in Accordance With the Bilateral Airworthiness Agreement?

These airplane models are manufactured in the United Kingdom and are type certificated for operation in the United States under the provisions of section 21.29 of the Federal Aviation Regulations (14 CFR 21.29) and the applicable bilateral airworthiness agreement. Pursuant to this bilateral airworthiness agreement, the CAA has kept FAA informed of the situation described above.

The FAA's Determination and an Explanation of the Provisions of this Proposed AD

What Has FAA Decided?

The FAA has examined the findings of the CAA; reviewed all available information, including the service information referenced above; and determined that:

—The unsafe condition referenced in this document exists or could develop on other Shorts Models SC-7 Series 2 and SC-7 Series 3 of the same type design that are on the U.S. registry;

—The actions specified in the previously-referenced service information should be accomplished on the affected airplanes; and

—AD action should be taken in order to correct this unsafe condition.

What Would This Proposed AD Require?

This proposed AD would require you to incorporate the actions in the previously-referenced service bulletins.

Cost Impact

How Many Airplanes Would This Proposed AD Impact?

We estimate that this proposed AD affects 22 airplanes in the U.S. registry.

What Would Be the Cost Impact of This Proposed AD on Owners/Operators of the Affected Airplanes?

The impact of this proposed AD would 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 proposed 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 proposed 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 Proposed AD

What Would Be the Compliance Time of This Proposed AD?

The compliance time of this proposed 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 Proposed 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 proposed AD should 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

Would This Proposed AD Impact Various Entities?

The regulations proposed herein 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. Therefore, it is determined that this proposed rule would not have federalism implications under Executive Order 13132.

Would This Proposed AD Involve a Significant Rule or Regulatory Action?

For the reasons discussed above, I certify that this proposed 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) if promulgated, 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 draft regulatory evaluation prepared for this action has been placed 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
• Safety

The Proposed Amendment

Accordingly, under the authority delegated to me by the Administrator, the Federal Aviation Administration proposes to amend 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 airworthiness directive (AD) to read as follows:

Short Brothers and Harland Ltd.: 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 fatigue failure of critical structure of the aircraft. Such failure could result in reduced structural integrity of the aircraft with consequent failure of the primary structural components and possibly result in structural failure during flight.

(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 the effective date of this AD, whichever occurs later. The following table presents the life limits:

Serial No.	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 encompass either 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 encompassing either 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 No.	Extended life limit
(1) SH1845	13,456 hours.
(2) SH1847	20,200 hours.
(3) SH1883	15,000 hours.
(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 encompass either 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) How do I get copies of the documents referenced in this AD? You may get copies of the documents referenced in this AD from Short Brothers PLC, P.O. Box 241, Airport Road, Belfast BT3 9DZ Northern Ireland; telephone: [phone]; facsimile: [phone]. You may view these documents at FAA, Central Region, Office of the Regional Counsel, 901 Locust, Room 506, Kansas City, Missouri 64106.

Note 4:

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

Issued in Kansas City, Missouri, on November 5, 2002.

Michael Gallagher,

Manager, Small Airplane Directorate, Aircraft Certification Service.