02-28409. Airworthiness Directives; Robert E. Rust Models DeHavilland DH.C1 Chipmunk 21, 22, and 22A 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 certain Robert E. Rust (R.E. Rust) Models DeHavilland DH.C1 Chipmunk 21, 22, and 22A airplanes. This proposed AD would require you to check the airplane logbook to determine whether certain modifications have been incorporated on the airplane and incorporate the modifications that have not already been accomplished. This proposed AD is the result of the manufacturer performing a design study on the structural integrity of certain parts and reports of service failure of other parts installed on the affected airplanes. The actions specified by this proposed AD are intended to prevent reduced structural integrity in the primary structure of the airplane, which could result in failure of the rudder torque tube, elevator fasteners, and the vertical fin rear spar, or jamming or damage to the elevator. Such failures could lead to loss of control of the airplane.

DATES:

The Federal Aviation Administration (FAA) must receive any comments on this proposed rule on or before January 13, 2003.

ADDRESSES:

Submit comments to FAA, Central Region, Office of the Regional Counsel, Attention: Rules Docket No. 2000-CE-66-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-66-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 DeHavilland Support Limited, Duxford Airfield, Bldg. 213, Cambridgeshire, CB2 4QR, United Kingdom, telephone: [phone], facsimile: [phone], e-mail: [e-mail]. You may also view this information at the Rules Docket at the address above.

FOR FURTHER INFORMATION CONTACT:

Cindy Lorenzen, Aerospace Engineer, FAA, Atlanta Aircraft Certification Office, 1895 Phoenix Boulevard, Suite 450, Atlanta, Georgia; 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-66-AD.” We will date stamp and mail the postcard back to you.

Discussion

What Events Have Caused This Proposed AD?

The FAA has received reports that an unsafe condition may exist on certain R.E. Rust Models DeHavilland DH.C1 Chipmunk 21, 22, and 22A airplanes. Failure reports of the rudder torque tube and elevator control fasteners on in-service airplanes and design studies by the manufacturer on the structural integrity of the glider towing attachment bolt and the vertical fin rear spar prompted us to issue this proposed AD.

We have determined that failure of the rudder torque tube, the elevator control fasteners, the vertical fin rear spar, and the glider towing attachment bolt is caused by fatigue cracking and overload. As a result of the design studies, the manufacturer developed specific modifications to strengthen the affected areas of the airplane.

What Are the Consequences If the Condition Is Not Corrected?

These conditions, if not corrected, could result in failure of the rudder torque tube, elevator fasteners, and the vertical fin rear spar, or jamming or damage to the elevator. Such failures could lead to loss of control of the airplane.

Is There Service Information That Applies to This Subject?

British Aerospace Aerostructures Limited (now DeHavilland Support Limited) has issued BAe Aircraft Technical News Sheet CT (C1) No. 200, Issue 1, dated March 1, 1997.

What Are the Provisions of This Service Information?

The service information includes procedures for inspecting the airplane to:

Determine if Modifications H 225, H 269, and H 360 are incorporated for all affected airplanes; and

Determine if Modification H 275 is incorporated for airplanes that incorporate Modification H 197 (glider towing capabilities).

The service information also specifies incorporating these modifications if not already incorporated.

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

What Has FAA Decided?

After examining the circumstances and reviewing all available information related to the incidents described above, we have determined that:

the unsafe condition referenced in this document exists or could develop on other R.E. Rust Models DeHavilland DH.C1 Chipmunk 21, 22, and 22A airplanes of the same type design;

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 check the airplane logbook to determine whether certain modifications have been incorporated on the airplane and incorporate the modifications that have not already been accomplished

Cost Impact

How Many Airplanes Would This Proposed AD Impact?

We estimate that this proposed AD affects 54 airplanes in the U.S. registry.

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

We estimate the following costs to accomplish any necessary modifications that would be required based on the results of the proposed logbook check We have no way of determining the number of airplanes that may need such modification.

Modification	Labor cost	Parts cost	Total cost per airplane
H 225	40 workhours × 60 = $2,400	$1,470	$2,400 + $1,470 = $3,870.
H 269	4 workhours × 60 = $240	$203 each (2 per airplane)	$240 + $406 ($203 × 2) = $646.
H 275	43 workhours × $60 = $180	$203 each (2 per airplane)	$180 + $406 ($230 × 2) = $586.
H 360	20 workhours × $60 = $1,200	$1,150	$1,200 + $1,150 = $2,350.

Compliance Time of This Proposed AD

What Would Be the Compliance Time of This Proposed AD?

The compliance time of this proposed AD is “within the next 90 days after the effective date of this AD.”

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

Failure of the rudder torque tube, the elevator control fasteners, the vertical fin rear spar, and the glider towing attachment bolt is only unsafe during airplane operation. However, this unsafe condition is not a result of the number of times the airplane is operated. The chance of this situation occurring is the same for an airplane with 50 hours time-in-service (TIS) as it would be for as airplane with 1,000 hours TIS.

For this reason, the FAA has determined that a compliance based on calendar time should be utilized in this proposed AD in order to assure that the unsafe condition is addressed on all airplanes in a reasonable time period.

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:

Robert E. Rust: Docket No. 2000-CE-66-AD

(a) What airplanes are affected by this AD? This AD affects R.E. Rust Models DeHavilland DH.C1 Chipmunk 21, 22, and 22A airplanes, serial numbers C1-001 through C1-1014, that are type certificated in any category.

Note 1:

We recommend all owners/operators of DeHavilland DH.C1 Chipmunk 21, 22, and 22A airplanes, serial numbers C1-001 through C1-1014, with experimental airworthiness certificates comply with the actions required in this AD.

(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 reduced structural integrity in the primary structure of the airplane, which could result in failure of the rudder torque tube, elevator fasteners, and the vertical fin rear spar, or jamming or damage to the elevator. Such failures could lead to loss of control of the airplane.

(d) What actions must I accomplish to address this problem? To address this problem, you must accomplish the following:

Actions	Compliance	Procedures
(1) Check the airplane logbook (i) For all affected airplanes: to determine if Modifications H 225, H 269, and H 360 are incorporated; and (ii) For only these airplanes that incorporate Modification H 197 (glider towing capabilities): to determine if Modification H 275 is incorporated.	Within the next 90 days after the effective date of this AD	The owner/operator holding at least a private pilot certificate as authorized by section 43.7 of the Federal Aviation Regulations (14 CFR 43.7) may check the airplane logbook.
(2) If, by checking the airplane logbook, you can positively determine that all the applicable modifications in paragraphs (d)(1)(i) and (d)(1)(ii) are incorporated, you must make an entry into the aircraft records that shows compliance with paragraphs (d)(1) and (d)(2) of this AD in accordance with section 43.9 of the Federal Aviation Regulations (14 CFR 43.9)	Not applicable	The owner/operator holding at least a private pilot certificate as authorized by section 43.7 of the Federal Aviation Regulations (14 CFR 43.7) may check the airplane logbook.
(3) If, by checking the airplane logbook, you determine that all the applicable modifications in paragraphs (d)(1)(i) and (d)(1)(ii) are not incorporated, or you cannot positive show that they are incorporated. (1) Incorporate each missing modification; and (ii) You must make an entry into the aircraft records that shows compliance with this portion of the AD in accordance with seciton 43.9 of the Federal Aviation Regulations (14 CFR 43.9)	Within the next 90 days after the effective date of this AD, unless already accomplished	British Aerospace Aerostructures Limited has issued BAE Aircraft Technical News Sheet CT (C1) No. 200, Issue 1, dated March 1, 1997.
(4) Do not incorporate Modification H 197 unless Modification H 275 has also been incorporated	As of the effective date of this AD	British Aerospace Aerostructures Limited has issued BA3 Aircraft Technical News Sheet CT (C1) No. 200, Issue 1, dated March 1, 1997.

Note 2:

Although not required by this AD, FAA highly recommends you incorporate Modification H 282.

(e) 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 Manager, Atlanta Aircraft Certification Office (ACO), approves your alternative. Submit your request through an FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Atlanta ACO.

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 (e) 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.

(f) Where can I get information about any already-approved alternative methods of compliance? Contact Cindy Lorenzen, Aerospace Engineer, FAA, Atlanta Aircraft Certification Office, 1895 Phoenix Boulevard, Suite 450, Atlanta, Georgia; telephone: [phone]; facsimile: [phone].

(g) 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.

(h) How do I get copies of the documents referenced in this AD? You may get copies of the documents referenced in this AD from DeHavilland Support Limited, Duxford Airfield, Bldg. 213, Cambridgeshire, CB2 4QR, United Kingdom, telephone: [phone], facsimile: [phone], e-mail: [e-mail]. You may view these documents at FAA, Central Region, Office of the Regional Counsel, 901 Locust, Room 506, Kansas City, Missouri 64106.

Issued in Kansas City, Missouri, on October 31, 2002.

Michael Gallagher,

Manager, Small Airplane Directorate, Aircraft Certification Service.