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Proposed Rule

Airworthiness Directives; Honeywell, Inc., Part Number HG1075AB05 and HG1075GB05 Inertial Reference Units

Document Details

Information about this document as published in the Federal Register.

Published Document

This document has been published in the Federal Register. Use the PDF linked in the document sidebar for the official electronic format.

Start Preamble

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 Honeywell, Inc. part number (P/N) HG1075AB05 and HG1075GB05 inertial reference units (IRU) that are installed on aircraft. This proposed AD would require you to inspect the affected IRU's for proper function and remove the IRU either immediately or at a certain time depending on the result of the inspection. This proposed AD is the result of a report that these IRU's may not function when using backup battery power in certain installations. The actions specified by this proposed AD are intended to ensure the correct transition of the IRU to backup battery power upon the loss of primary power. Failure of an IRU to transition to backup battery power could result in loss of attitude, heading, and position reference and lead to the pilot making flight decisions that put the aircraft in unsafe flight conditions.

DATES:

The Federal Aviation Administration (FAA) must receive any comments on this proposed rule on or before March 29, 2002.

ADDRESSES:

Submit comments to FAA, Central Region, Office of the Regional Counsel, Attention: Rules Docket No. 2001-CE-28-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 get service information that applies to this proposed AD from Honeywell, Inc., Commercial Aviation Products, 8840 Evergreen Boulevard, Minneapolis, Minnesota 55433-6040. You may also view this information at the Rules Docket at the address above.

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FOR FURTHER INFORMATION CONTACT:

Wesley Rouse, Aerospace Engineer, FAA, Chicago Aircraft Certification Office, 2300 E. Devon Avenue, Des Plaines, Illinois 60018; telephone: (847) 294-7564; facsimile: (847) 294-7834.

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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 comments, you must include a self-addressed, stamped postcard. On the postcard, write “Comments to Docket No. 2001-CE-28-AD.” We will date stamp and mail the postcard back to you.

Discussion

What Events Have Caused This Proposed AD?

A ground test for proper inertial reference unit (IRU) function revealed a wiring defect that is attributed to a manufacturing error on certain Honeywell, Inc. part number (P/N) HG1075AB05 and HG1075GB05 IRU's. This wiring defect disables the IRU's capability to detect a loss of primary input power and transition to backup battery input power in some installations.

The affected IRU's incorporate the following:

—P/N HG1075AB05: any serial number (last four digits) 0644 through 0723 (excluding 0652 and 0659) that incorporates modification status 3; and

—P/N HG1075GB05: serial number (last four digits) 0652 or 0659 that incorporates modification status 2.

What Are the Consequences if the Condition Is Not Corrected?

This condition, if not corrected, could result in loss of attitude, heading, and position reference and lead to the pilot making flight decisions that put the aircraft in unsafe flight conditions.

Is There Service Information That Applies to This Subject?

Honeywell, Inc. has issued the following:

—Alert Service Bulletin HG1075AB-34-A0013, dated May 21, 2001; and

—Alert Service Bulletin HG1075GB-34-A0005, dated May 21, 2001.

What Are the Provisions of This Service Information?

These service bulletins include procedures for inspecting the affected IRU's for proper function. It also Start Printed Page 3845specifies having the IRU returned to Honeywell and modified.

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 any type design aircraft that incorporates one of the affected IRU's;

—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 inspect any affected IRU for proper function and remove the IRU either immediately or at a certain time depending on the result of the inspection.

Cost Impact

How Many Airplanes Would This Proposed AD Impact?

We estimate that this proposed AD affects 80 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 the proposed inspection and modification:

Labor costParts costTotal cost per airplaneTotal cost on U.S. operators
2 workhours at $60 per hour = $120Honeywell to provide at no cost$120$9,600

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.

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List of Subjects in 14 CFR Part 39

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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:

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PART 39—AIRWORTHINESS DIRECTIVES

1. The authority citation for part 39 continues to read as follows:

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Authority: 49 U.S.C. 106(g), 40113, 44701.

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[Amended]

2. FAA amends § 39.13 by adding a new airworthiness directive (AD) to read as follows:

Honeywell, Inc.: Docket No. 2001-CE-28-AD.

(a) What aircraft are affected by this AD? This AD affects any aircraft, certificated in any category, that incorporates one of the following:

(1) Inertial Reference Unit (IRU) part number (P/N) HG1075AB05, any serial number (last four digits) 0644 through 0723 (excluding 0652 and 0659), that incorporates modification status 3; or

(2) IRU P/N HG1075GB05, serial number (last four digits) 0652 or 0659, that incorporates modification status 2.

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

(c) What problem does this AD address? The actions specified by this AD are intended to ensure the correct transition of the IRU to battery power upon the loss of primary power. Failure of an IRU to transition to backup battery power could result in loss of attitude, heading, and position reference and lead to the pilot making flight decisions that put the aircraft in unsafe flight conditions.

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

ActionsComplianceProcedures
(1) Inspect any affected IRU for proper functionWithin the next 50 hours time-in-service (TIS) after the effective date of this ADIn accordance with the instructions in Honeywell Alert Service Bulletin HG1075AB-34-A0013, dated May 21, 2001; or Honeywell Alert Service Bulletin HG1075GB-34-A0005, dated May 21, 2001, as applicable.
(2) Remove any affected IRU from the airplaneIf found to not function properly during the inspection required by paragraph (d)(1) of this AD, remove prior to further flight after the inspection. If found to function properly, remove within 200 hours time-in-service (TIS) after the inspection required by paragraph (d)(1) of this ADIn accordance with the instructions in Honeywell Alert Service Bulletin HG1075AB-34-A0013, dated May 21, 2001; or Honeywell Alert Service Bulletin HG1075GB-34-A0005, dated May 21, 2001, as applicable.
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(3) Do not install, on any aircraft, one of the IRU's identified in paragraphs (a)(1) and (a)(2) of this AD, unless it has been modified at Honeywell, Inc. and updated to one of the following: (i) IRU P/N HG1075AB05 IRU Mod 7; or (ii) IRU P/N HG1075GB05 IRU Mod 6As of the effective date of this ADNot Applicable.

(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, Chicago Aircraft Certification Office, approves your alternative. Send your request through an FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Chicago Aircraft Certification Office.

Note:

This AD applies to any aircraft with an inertial reference unit (IRU) installed as identified in paragraphs (a)(1) and (a)(2) of this AD, regardless of whether the aircraft has been modified, altered, or repaired in the area subject to the requirements of this AD. For aircraft 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 Wesley Rouse, Aerospace Engineer, FAA, Chicago Aircraft Certification Office, 2300 E. Devon Avenue, Des Plaines, Illinois 60018; telephone: (847) 294-8113; facsimile: (847) 294-7834.

(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 Honeywell, Inc., Commercial Aviation Products, 8840 Evergreen Boulevard, Minneapolis, Minnesota 55433-6040. You may view these documents at FAA, Central Region, Office of the Regional Counsel, 901 Locust, Room 506, Kansas City, Missouri 64106.

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Issued in Kansas City, Missouri, on January 18, 2002.

James E. Jackson,

Acting Manager, Small Airplane Directorate, Aircraft Certification Service.

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[FR Doc. 02-1967 Filed 1-25-02; 8:45 am]

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