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Proposed Rule

Airworthiness Directives; Raytheon Model HS.125 Series 700A Airplanes, Model BAe.125 Series 800A Airplanes, and Model Hawker 800 and Hawker 800XP Airplanes

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.

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AGENCY:

Federal Aviation Administration (FAA), Department of Transportation (DOT).

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

The FAA proposes to adopt a new airworthiness directive (AD) for certain Raytheon Model HS.125 series 700A airplanes, Model BAe.125 series 800A airplanes, and Model Hawker 800 and Hawker 800XP airplanes. This proposed AD would require an inspection to determine the current rating of the circuit breakers of certain cockpit ventilation and avionics cooling system blowers; and for replacing the circuit breakers and modifying the blower wiring, as applicable. This proposed AD is prompted by a report indicating that a blower motor seized up and gave off smoke. Investigation revealed inadequate short circuit protection on the blower motor electrical circuit. We are proposing this AD to prevent smoke and fumes in the cockpit in the event that a blower motor seizes and overheats due to excessive current draw.

DATES:

We must receive comments on this proposed AD by March 10, 2005.

ADDRESSES:

Use one of the following addresses to submit comments on this proposed AD.

  • DOT Docket Web site: Go to http://dms.dot.gov and follow the instructions for sending your comments electronically.
  • Government-wide Rulemaking Web site: Go to http://www.regulations.gov and follow the instructions for sending your comments electronically.
  • Mail: Docket Management Facility, U.S. Department of Transportation, 400 Seventh Street SW., Nassif Building, room PL-401, Washington, DC 20590.
  • By Fax: (202) 493-2251.
  • Hand Delivery: Room PL-401 on the plaza level of the Nassif Building, 400 Seventh Street SW., Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

For service information identified in this proposed AD, contact Raytheon Aircraft Company, Department 62, P.O. Box 85, Wichita, Kansas 67201-0085.

You can examine the contents of this AD docket on the Internet at http://dms.dot.gov, or in person at the Docket Management Facility, U.S. Department of Transportation, 400 Seventh Street SW., room PL-401, on the plaza level of the Nassif Building, Washington, DC. This docket number is FAA-2005-20111; the directorate identifier for this docket is 2004-NM-154-AD.

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FOR FURTHER INFORMATION CONTACT:

Philip Petty, Aerospace Engineer, Electrical Systems Branch, ACE-119W, FAA, Wichita Aircraft Certification Office, 1801 Airport Road, room 100, Mid-Continent Airport, Wichita, Kansas 67209; telephone (316) 946-4139; fax (316) 946-4107.

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SUPPLEMENTARY INFORMATION:

Comments Invited

We invite you to submit any relevant written data, views, or arguments regarding this proposed AD. Send your comments to an address listed under ADDRESSES. Include “Docket No. FAA-2005-20111; Directorate Identifier 2004-NM-154-AD” in the subject line of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of the proposed AD. We will consider all comments submitted by the closing date and may amend the proposed AD in light of those comments.

We will post all comments we receive, without change, to http://Start Printed Page 3319dms.dot.gov, including any personal information you provide. We will also post a report summarizing each substantive verbal contact with FAA personnel concerning this proposed AD. Using the search function of that Web site, anyone can find and read the comments in any of our dockets, including the name of the individual who sent the comment (or signed the comment on behalf of an association, business, labor union, etc.). You can review DOT's complete Privacy Act Statement in the Federal Register published on April 11, 2000 (65 FR 19477-78), or you can visit http://dms.dot.gov.

Examining the Docket

You can examine the AD docket on the Internet at http://dms.dot.gov, or in person at the Docket Management Facility office between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The Docket Management Facility office (telephone (800) 647-5227) is located on the plaza level of the Nassif Building at the DOT street address stated in the ADDRESSES section. Comments will be available in the AD docket shortly after the DMS receives them.

Discussion

We have received a report indicating that a cockpit ventilation and avionics cooling system blower motor seized up and gave off smoke on a Raytheon Hawker Model 125-800 airplane. Investigation revealed inadequate short circuit protection on the blower motor electrical circuit. This condition, if not corrected, could result in smoke and fumes in the cockpit in the event that a blower motor seizes and overheats due to excessive current draw.

Relevant Service Information

We have reviewed Raytheon Service Bulletin SB 24-3272, Revision 1, dated October 2000. The service bulletin describes procedures for inspecting to determine the current rating of the circuit breakers of certain cockpit ventilation and avionics cooling system blowers; and for replacing the circuit breakers and modifying the blower wiring, if applicable. Accomplishing the actions specified in the service information is intended to adequately address the unsafe condition.

FAA's Determination and Requirements of the Proposed AD

We have evaluated all pertinent information and identified an unsafe condition that is likely to exist or develop on other airplanes of this same type design. Therefore, we are proposing this AD, which would require accomplishing the actions specified in the service information described previously, except as discussed under “Difference Between the Proposed AD and the Service Information.”

Difference Between the Proposed AD and Service Information

Although the service bulletin specifies that operators may contact the manufacturer for disposition of certain repair conditions, this proposed AD would require operators to repair those conditions according to a method approved by the FAA.

Costs of Compliance

There are about 350 airplanes of the affected design in the worldwide fleet. This proposed AD would affect about 250 airplanes of U.S. registry. The following table provides the estimated costs for U.S. operators to comply with this proposed AD.

Inspection and Modification Costs

ActionWork hoursAverage labor rate per hourParts costCost per airplane
Inspection1$65No parts$65
Modification of cockpit blower circuit, if applicable265500630
Modification of instrument panel blower circuit, if applicable12655001,280

Authority for This Rulemaking

Title 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety. Subtitle I, section 106, describes the authority of the FAA Administrator. Subtitle VII, Aviation Programs, describes in more detail the scope of the Agency's authority.

We are issuing this rulemaking under the authority described in subtitle VII, part A, subpart III, section 44701, “General requirements.” Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action.

Regulatory Findings

We have determined that this proposed AD would not have federalism implications under Executive Order 13132. This proposed AD 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.

For the reasons discussed above, I certify that the proposed regulation:

1. Is not a “significant regulatory action” under Executive Order 12866;

2. Is not a “significant rule” under the 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.

We prepared a regulatory evaluation of the estimated costs to comply with this proposed AD. See the ADDRESSES section for a location to examine the regulatory evaluation.

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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 FAA proposes to amend 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. The FAA amends § 39.13 by adding the following new airworthiness directive (AD):

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Raytheon Aircraft Company: Docket No. FAA-2005-20111; Directorate Identifier 2004-NM-154-AD.

Comments Due Date

(a) The Federal Aviation Administration (FAA) must receive comments on this AD action by March 10, 2005.

Affected ADs

(b) None.

Applicability

(c) This AD applies to Raytheon Model HS.125 series 700A airplanes, Model BAe.125 series 800A airplanes, and Model Hawker 800 and Hawker 800XP airplanes; equipped with Brailsford TBL-2.5 blowers; as identified in Raytheon Service Bulletin SB 24-3272, Revision 1, dated October 2000; certificated in any category.

Unsafe Condition

(d) This AD was prompted by a report indicating that a cockpit ventilation and avionics cooling system blower motor seized up and gave off smoke due to inadequate short circuit protection on the blower motor electrical circuit. We are issuing this AD to prevent smoke and fumes in the cockpit in the event that a blower motor seizes and overheats due to excessive current draw.

Compliance

(e) You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.

Inspection and Corrective Actions

(f) Within 600 flight hours or six months after the effective date of this AD, whichever occurs first, inspect to determine the current rating of the circuit breakers of certain cockpit ventilation and avionics cooling system blowers; and replace the circuit breakers and modify the blower wiring, as applicable; by doing all the actions in accordance with the Accomplishment Instructions of Raytheon Service Bulletin SB 24-3272, Revision 1, dated October 2000.

Contacting the Manufacturer

(g) Where the service bulletin suggests contacting the manufacturer for information if any difficulties are encountered while accomplishing the service bulletin, this AD would require you to contact the Manager, Wichita Aircraft Certification Office (ACO), FAA.

Alternative Methods of Compliance (AMOCs)

(h) The Manager, Wichita ACO, has the authority to approve AMOCs for this AD, if requested in accordance with the procedures found in 14 CFR 39.19.

Start Signature

Issued in Renton, Washington, on January 12, 2005.

Ali Bahrami,

Manager, Transport Airplane Directorate, Aircraft Certification Service.

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[FR Doc. 05-1221 Filed 1-21-05; 8:45 am]

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