Airworthiness Directives; Raytheon Model DH.125, Model HS.125, Model BH.125, Model BAe125 Series 800A (Including Major Variants C-29A and U1-25), Model Hawker 800, Model Hawker 800XP, and Model Hawker 1000 Series Airplanes

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain Raytheon Model DH.125, Model HS.125, Model BH.125, Model BAe.125 Series 800A, Model Hawker 800, Model Hawker 800XP, and Model Hawker 1000 series airplanes. This proposal would require leak checks and inspections for corrosion of the pitot/static and stall vent drain valves, and replacement of certain components, if necessary. This proposal is prompted by reports of plugged or taped drain valves as well as consequent corrosion of certain drain valves. The actions specified by the proposed AD are intended to prevent erroneous altimeter and airspeed indications due to plugged or taped pitot/static and stall vent drain valves.

DATES:

Comments must be received by August 3, 2000.

ADDRESSES:

Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 99-NM-376-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056. Comments may be inspected at this location between 9 a.m. and 3 p.m., Monday through Friday, except Federal holidays.

The service information referenced in the proposed rule may be obtained from Raytheon Aircraft Company, Manager Service Engineering, Hawker Customer Support Department, P. O. Box 85, Wichita, Kansas 67201-0085. This information may be examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the FAA, Small Airplane Directorate, Wichita Aircraft Certification Office, 1801 Airport Road, Room 100, Mid-Continent Airport, Wichita, Kansas.

FOR FURTHER INFORMATION CONTACT:

Paul DeVore, Aerospace Engineer, Systems and Propulsion Branch, ACE-116W, FAA, Small Airplane Directorate, Wichita, Kansas 672029; telephone (316) 946-4142; fax (316) 946-4407.

SUPPLEMENTARY INFORMATION:

Comments Invited

Interested persons are invited to participate in the making of the proposed rule by submitting such written data, views, or arguments as they may desire. Communications shall identify the Rules Docket number and be submitted in triplicate to the address specified above. All communications received on or before the closing date for comments, specified above, will be considered before taking action on the proposed rule. The proposals contained in this notice may be changed in light of the comments received.

Comments are specifically invited on the overall regulatory, economic, environmental, and energy aspects of the proposed rule. All comments submitted will be available, both before and after the closing date for comments, in the Rules Docket for examination by interested persons. A report summarizing each FAA-public contact concerned with the substance of this proposal will be filed in the Rules Docket.

Commenters wishing the FAA to acknowledge receipt of their comments submitted in response to this notice must submit a self-addressed, stamped postcard on which the following statement is made: “Comments to Docket Number 99-NM-376-AD.” The postcard will be date stamped and returned to the commenter.

Availability of NPRMs

Any person may obtain a copy of this NPRM by submitting a request to the FAA, Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 99-NM-376-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.

Discussion

The FAA has received reports of plugged or taped pitot/static and stall vent drain valves. The reports indicate that corrosion also was detected in some valves. This condition, if not corrected, could result in erroneous altimeter and airspeed indications.

Explanation of Relevant Service Information

The FAA has reviewed and approved Raytheon Aircraft Service Bulletin SB 34-3207, dated August 1999, which describes procedures for performing repetitive leak checks of the pitot/static and stall vent drain valves and inspections for corrosion of the drain valve system, and corrective actions, such as replacement of certain components of the drain valve system. That service bulletin also references the following two service bulletins as additional sources of service information.

Raytheon Aircraft Service Bulletin SB 34-3223, dated August 1999, describes the application of a temporary seal for the pitot/static and stall vent drain valves.

Raytheon Aircraft Service Bulletin SB 34-3282, dated August 1999, describes the installation of a new insert for the pitot/static and stall vent drain valves that will provide a positive seal of the valves. If accomplished on all drain valves, the modification would eliminate the need for the repetitive leak checks described in SB 34-3207.

Explanation of Requirements of Proposed Rule

Since an unsafe condition has been identified that is likely to exist or develop on other products of this same type design, the proposed AD would require leak checks of the pitot/static and stall vent drain valve systems and corrective actions, if necessary. The proposed AD would provide an optional action to apply a temporary seal of the drain valve for certain drain valves that are operative but that are leaking. The actions would be required to be accomplished in accordance with the service bulletins described previously. The proposed AD also would provide an optional terminating action for the proposed repetitive inspections that involves installing a new insert for the drain valve system.

Cost Impact

There are approximately 900 airplanes of the affected design in the worldwide fleet. The FAA estimates that 585 airplanes of U.S. registry would be affected by this proposed AD, that it would take approximately 4 work hours per airplane to accomplish the proposed actions, and that the average labor rate is $60 per work hour. Based on these figures, the cost impact of the proposed AD on U.S. operators is estimated to be $140,400, or $240 per airplane.

The cost impact figure discussed above is based on assumptions that no operator has yet accomplished any of the proposed requirements of this AD action, and that no operator would accomplish those actions in the future if this AD were not adopted.

Should an operator accomplish the optional modification to the drain valve system, it would take approximately 1 work hour per airplane to accomplish, at an average labor rate of $60 per work hour. Based on these figures, the cost impact of the optional modification is estimated to be $60 per airplane.

Regulatory Impact

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 proposal would not have federalism implications under Executive Order 13132.

For the reasons discussed above, I certify that this 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) 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 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.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Safety

The Proposed Amendment

Accordingly, pursuant to 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.