AD 2002-13-08

This AD becomes effective on August 13, 2002.

The Director of the Federal Register approved the incorporation by reference of certain publications listed in the regulations as of August 13, 2002.

You may get the service information referenced in this AD from Bombardier Inc., Bombardier Regional Aircraft Division, 123 Garratt Boulevard, Downsview, Ontario, Canada M3K 1Y5; telephone: (416) 633-7310. You may view this information at the Federal Aviation Administration (FAA), Central Region, Office of the Regional Counsel, Attention: Rules Docket No. 97-CE-70-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.

Mr. Jon Hjelm, Aerospace Engineer, New York Aircraft Certification Office, 10 Fifth Street, 3rd Floor, Valley Stream, New York, 11581-1200, telephone: (516) 256-7523, facsimile: (516) 568-2716.

What Events Have Caused This AD?

Transport Canada, which is the airworthiness authority for Canada, notified FAA that an unsafe condition may exist on certain de Havilland Models DHC-2 Mk. I, DHC-2 Mk. II, and DHC-2 Mk. III airplanes. Transport Canada reports incidents of corrosion found in the area of the elevator tip rib underneath the mass balance weights on several of the above-referenced airplanes.

What Is the Potential Impact if FAA Took no Action?

These conditions, if not detected and corrected, could result in loss of balance weight during flight and the elevator control surface separating from the airplane.

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 certain de Havilland Models DHC-2 Mk. I, DHC-2 Mk. II, and DHC-2 Mk. III airplanes. This proposal was published in the Federal Register as a notice of proposed rulemaking (NPRM) on March 4, 2002 (67 FR 9627). The NPRM proposed to require you to modify the elevator tip rib on each elevator; repetitively inspect underneath the mass balance weights at the elevator rib tip for corrosion; and either remove the corrosion or replace the corroded elevator tip rib depending on the corrosion damage.

Was the Public Invited To Comment?

The FAA encouraged interested persons to participate in the making of this amendment. We did not receive any comments on the proposed rule or on our determination of the cost to the public.

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.

How Many Airplanes Does This AD Impact?

We estimate that this AD affects 160 airplanes in the U.S. registry.

What is the Cost Impact of This AD on Owners/Operators of the Affected Airplanes?

We estimate the following costs to accomplish the modification and initial inspection:

These figures only take into account the modification and initial inspection costs and do not take into account the costs of any of the repetitive inspections or the cost to replace any elevator tip rib that would be found corroded past a certain extent. We have no way of determining the number of repetitive inspections each owner/operator will incur over the life of each affected airplane or the number of elevator tip ribs that will need to be replaced.

What Will be the Compliance Time of This AD?

The compliance time of this AD is “within the next 6 calendar months after the effective date of this AD.”

Why Is the Compliance Time Presented in Calendar Time Instead of Hours Time-in-Service (TIS)?

We have determined that a calendar time compliance is the most desirable method because the unsafe condition described in this AD is caused by corrosion. Corrosion develops regardless of whether the airplane is in service and is not a result of airplane operation. Therefore, to ensure that the above-referenced condition is detected and corrected on all airplanes within a reasonable period of time without inadvertently grounding any airplanes, a compliance schedule based upon calendar time instead of hours TIS is required.

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.

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: