# 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 Fokker Model F.28 Mark 1000, 2000, 3000, and 4000 series airplanes. This proposal would require a one-time review of the maintenance records to determine if tripping of the fuel boost pump circuit breakers has been recorded, repetitive inspections to detect fuel leakage from the fuel boost pump wiring conduits, and corrective actions, if necessary. This proposal also would require replacement of the three single wires inside the metal conduit sleeve of the fuel boost pumps with new wires protected by a polyamide sleeve, which would terminate the repetitive inspections. This proposal is prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified by the proposed AD are intended to prevent the fuel boost pump wiring from chafing, which could result in electrical arcing and a possible fuel tank ignition source. 

# DATES:

 Comments must be received by March 9, 2000. 

# ADDRESSES:

 Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 99-NM-358-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056. Comments may be inspected at this location between 9:00 a.m. and 3:00 p.m., Monday through Friday, except Federal holidays. 

The service information referenced in the proposed rule may be obtained from Fokker Services B.V., P.O. Box 231, 2150 AE Nieuw-Vennep, the Netherlands. This information may be examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington. 

# FOR FURTHER INFORMATION CONTACT:

 Norman B. Martenson, Manager, International Branch, ANM-116, FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 227-2110; fax (425) 227-1149.

# 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-358-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-358-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056. 

## Discussion 

The Rijksluchtvaartdienst (RLD), which is the airworthiness authority for the Netherlands, notified the FAA that an unsafe condition may exist on certain Fokker Model F.28 Mark 1000, 2000, 3000, and 4000 series airplanes. On July 17, 1996, a Boeing Model 747 series airplane was involved in an accident shortly after takeoff from John F. Kennedy International Airport in Jamaica, New York. Subsequent to the accident, the RLD advises that the manufacturer has conducted a Fuel System Safety Program (FSSP) investigation. This investigation revealed that, on an F.28 “Fellowship” series airplane, the wiring insulation layers of the fuel boost pumps can be damaged during removal and installation of the wiring, or by chafing within the conduits. Additionally, two separate incidents of arcing have been found in the metal conduits of the wiring of the fuel boost pumps. Circumferential cracks were found in the insulation layering of the fuel boost pump wiring. In some cases, the cracks extended down to the conductor of the wiring. This condition, if not corrected, could result in electrical arcing and a possible fuel tank ignition source. 

## Explanation of Relevant Service Information 

The manufacturer has issued Fokker Service Bulletin SBF28/28-046, dated September 1, 1999, which describes procedures for the following: 

- Part 1 of the Accomplishment Instructions: A one-time review of the maintenance records to determine if tripping of the fuel boost pump circuit breakers has been reported, and repetitive visual inspections to detect fuel leakage of the fuel boost pumps.
- Part 2, paragraph D., of the Accomplishment Instructions: Corrective actions for tripping of the fuel boost pump circuit breakers. These actions involve performing a resistance check of the wiring, and, if necessary, installing a new or serviceable fuel boost pump and correcting any system problems between the circuit breaker and the main landing gear (MLG) wheel bay connector, and repairing any fuel  Start Printed Page 6047                     leak in the metal conduit of the fuel boost pump. The corrective actions also involve performing one-time inspections (visual and boroscopic) to detect discrepancies (                     i.e.,                      arcing, chafing, and cracking) of the insulation layers of the wiring and wiring conduits, and replacing the wiring and repairing the wiring conduits.                 
- Part 2, paragraph E., of the Accomplishment Instructions: Corrective actions in the event that fuel leakage is detected from the fuel boost pump wiring conduits. The corrective actions involve inspecting the pressure bung for serviceability, and, if necessary, installing a new or serviceable pressure bung. Additionally, the corrective actions involve inspecting (visual and boroscopic) to detect discrepancies ( i.e.,                      arcing, chafing, and cracking) of the insulation layers of the wiring and wiring conduits, and replacing the wiring and repairing the wiring conduits.                 
- Part 3 of the Accomplishment Instructions: Replacement of the three single wires inside the metal conduit sleeve of the fuel boost pump with new wires protected by a polyamide sleeve. The replacement also involves performing a visual inspection, and, if necessary, a boroscopic inspection of the boost pump wiring to detect discrepancies ( i.e.,                      arcing, chafing, and cracking) of the insulation layers of the wiring and wiring conduits, and replacing the wiring and repairing the wiring conduits. Accomplishment of the replacement eliminates the need for the repetitive inspections.                 

Accomplishment of the actions specified in the service bulletin is intended to adequately address the identified unsafe condition. The RLD classified this service bulletin as mandatory and issued Dutch airworthiness directive BLA 1999-114, dated September 13, 1999, in order to assure the continued airworthiness of these airplanes in the Netherlands. 

## FAA's Conclusions 

This airplane model is manufactured in the Netherlands and is type certificated for operation in the United States under the provisions of section 21.29 of the Federal Aviation Regulations (14 CFR 21.29) and the applicable bilateral airworthiness agreement. Pursuant to this bilateral airworthiness agreement, the RLD has kept the FAA informed of the situation described above. The FAA has examined the findings of the RLD, reviewed all available information, and determined that AD action is necessary for products of this type design that are certificated for operation in the United States. 

## Explanation of Requirements of Proposed Rule 

Since an unsafe condition has been identified that is likely to exist or develop on other airplanes of the same type design registered in the United States, the proposed AD would require accomplishment of the actions specified in the service bulletin described previously. 

## Cost Impact 

The FAA estimates that 22 airplanes of U.S. registry would be affected by this proposed AD, that it would take approximately 1 work hour per airplane to accomplish the proposed review of the maintenance records, and that the average labor rate is $60 per work hour. Based on these figures, the cost impact of the review proposed by this AD on U.S. operators is estimated to be $1,320, or $60 per airplane. 

It would take approximately 3 work hours per airplane to accomplish the proposed repetitive inspection, at an average labor rate of $60 per work hour. Based on these figures, the cost impact of the proposed inspection by this AD on U.S. operators is estimated to be $3,960, or $180 per airplane, per inspection cycle. 

It would take approximately 33 work hours per airplane to accomplish the proposed modification, at an average labor rate of $60 per work hour. Required parts would cost approximately $1,355 per airplane. Based on these figures, the cost impact of the proposed modification by this AD on U.S. operators is estimated to be $73,370, or $3,335 per airplane. 

The cost impact figures discussed above are 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. 

## 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. 

§ 39.13 

2. Section 39.13 is amended by adding the following new airworthiness directive: 

**Fokker Services B.V:**                                 Docket 99-NM-358-AD.                            

*Applicability:*                                 Model F.28 Mark 1000, 2000, 3000, and 4000 series airplanes having serial numbers 11003 through 11241 inclusive and 11991 through 11994 inclusive, certificated in any category.                             

# Note 1:

 This AD applies to each airplane identified in the preceding applicability provision, 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 (f) 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 the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.

*Compliance:*                                 Required as indicated, unless accomplished previously.                             

To prevent the fuel boost pump wiring from chafing, which could result in electrical arcing and a possible fuel tank ignition source, accomplish the following: 

                                (a) Within 30 days after the effective date of this AD, perform a one-time inspection of the maintenance records of the airplane to determine if tripping of the fuel boost pump                                 Start Printed Page 6048                                circuit breakers has been reported within the last 30 days, in accordance with Part 1 of the Accomplishment Instructions of Fokker Service Bulletin SBF28/28-046, dated September 1, 1999.                             

(b) If resettable or unresettable tripping of the circuit breaker of the fuel boost pump is reported during the inspection required by paragraph (a) of this AD, or if such tripping is reported at any time subsequent to that inspection: Within 10 days after the date of the inspection or any occurrence, accomplish the applicable repair (including a resistance check and inspections of the wire and conduit for discrepancies), in accordance with Part 2 of the Accomplishment Instructions of Fokker Service Bulletin SBF28/28-046, dated September 1, 1999. If any discrepancy is detected during any inspection performed during the repair, prior to further flight, repair in accordance with the service bulletin. 

(c) In the event of any resettable or unresettable tripping of the circuit breakers of the fuel boost pump as indicated in paragraph (b) of this AD, the airplane may be operated for a period not to exceed 10 days after the occurrence, provided the circuit breaker of the fuel boost pump and fuel boost pump switch have been properly deactivated and placarded for flightcrew awareness, in accordance with the FAA-approved Master Minimum Equipment List (MMEL). 

(d) Within 30 days after the effective date of this AD, perform a general visual inspection to detect signs of fuel leakage from the wiring conduits of the fuel boost pumps, in accordance with Part 1 of the Accomplishment Instructions of Fokker Service Bulletin F28/28-046, dated September 1, 1999. If any fuel leakage is detected during the inspection, prior to further flight, isolate the fuel leak, and repair in accordance with Part 2 of the Accomplishment Instructions of the service bulletin. Thereafter, repeat the inspection at intervals not to exceed 90 days. 

# Note 2:

 For the purposes of this AD, a general visual inspection is defined as: “A visual examination of an interior or exterior area, installation, or assembly to detect obvious damage, failure, or irregularity. This level of inspection is made under normally available lighting conditions such as daylight, hangar lighting, flashlight, or drop-light, and may require removal or opening of access panels or doors. Stands, ladders, or platforms may be required to gain proximity to the area being checked.” 

(e) Replace the existing three single wires (including inspections) inside the metal conduits of the fuel boost pumps with three twisted wires protected by a polyamide braided wire sleeve, in accordance with Part 3 of the Accomplishment Instructions of Fokker Service Bulletin F28/28-046, dated September 1, 1999, at the time specified in paragraph (e)(1) or (e)(2) of this AD, as applicable. If any discrepancy is detected during any inspection required by this paragraph, prior to further flight, repair in accordance with the service bulletin. Accomplishment of the actions required by this paragraph constitutes terminating action for the actions required by this AD. 

(1) For airplanes that have accumulated less than 40,000 total flight hours as of the effective date of this AD: Within 2 years after the effective date of this AD. 

(2) For airplanes that have accumulated 40,000 or more total flight hours as of the effective date of this AD: Within 1 year after the effective date of this AD. 

## Alternative Methods of Compliance 

(f) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, International Branch, ANM-116, FAA, Transport Airplane Directorate. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, International Branch, ANM-116. 

# Note 3:

 Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the International Branch, ANM-116.

## Special Flight Permits 

(g) Special flight permits may be issued in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the airplane to a location where the requirements of this AD can be accomplished. 

# Note 4:

 The subject of this AD is addressed in Dutch airworthiness directive BLA 1999-114, dated September 13, 1999. 

Issued in Renton, Washington, on February 2, 2000. 

Donald L. Riggin, 

Acting Manager, Transport Airplane Directorate, Aircraft Certification Service. 

[FR Doc. 00-2830 Filed 2-7-00; 8:45 am] 

BILLING CODE 4910-13-P