E9-14410. Airworthiness Directives; Fokker Model F28 Mark 0070 and 0100 Airplanes

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

We propose to adopt a new airworthiness directive (AD) for the products listed above that would supersede an existing AD. This proposed AD results from mandatory continuing airworthiness information (MCAI) originated by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as:

A recent design review has been carried out on the F28 Mark 0070/0100 fuel system in accordance with the guidelines related to FAA SFAR 88 [Special Federal Aviation Regulation No. 88] (Fuel Tank Safety Program) and JAA [Joint Aviation Authorities] INT/POL/25/12. The review revealed that under certain failure conditions, prolonged dry running of the fuel transfer pumps may result in an ignition source in the centre wing fuel tank. This condition, if not corrected, could lead to ignition of flammable fuel vapors, resulting in fuel tank explosion and consequent loss of the airplane.

* * * * *

The proposed AD would require actions that are intended to address the unsafe condition described in the MCAI.

DATES:

We must receive comments on this proposed AD by July 20, 2009.

ADDRESSES:

You may send comments by any of the following methods:

• Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.
• Fax: [phone].
• Mail: U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue, SE., Washington, DC 20590.
• Hand Delivery: U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-40, 1200 New Jersey Avenue, SE., Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

For Fokker service information identified in this proposed AD, contact Fokker Services B.V., Technical Services Dept., P.O. Box 231, 2150 AE Nieuw-Vennep, the Netherlands; telephone [phone]; fax [phone]; e-mail [e-mail]; Internet http://www.myfokkerfleet.com.

For AlliedSignal Grimes Aerospace and Honeywell service information identified in this proposed AD, contact Honeywell Aerospace, Technical Publications and Distribution, M/S 2101-201, P.O. Box 52170, Phoenix, Arizona 85072-2170; telephone [phone]; fax [phone]; Internet http://www.honeywell.com.

You may review copies of the referenced service information at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington. For information on the availability of this material at the FAA, call 425-227-1221 or 425-227-1152.

Examining the AD Docket

You may examine the AD docket on the Internet at http://www.regulations.gov; or in person at the Docket Operations office between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this proposed AD, the regulatory evaluation, any comments received, and other information. The street address for the Docket Operations office (telephone [phone]) is in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT:

Tom Rodriguez, Aerospace Engineer, International Branch, ANM-116, Transport Airplane Directorate, FAA, 1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone [phone]; fax [phone].

SUPPLEMENTARY INFORMATION:

 

Comments Invited

We invite you to send any written relevant data, views, or arguments about this proposed AD. Send your comments to an address listed under the ADDRESSES section. Include “Docket No. FAA-2009-0563; Directorate Identifier 2008-NM-180-AD” at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this proposed AD. We will consider all comments received by the closing date and may amend this proposed AD based on those comments.

We will post all comments we receive, without change, to http://www.regulations.gov,, including any personal information you provide. We will also post a report summarizing each substantive verbal contact we receive about this proposed AD.

Discussion

The FAA has examined the underlying safety issues involved in fuel tank explosions on several large transport airplanes, including the adequacy of existing regulations, the service history of airplanes subject to those regulations, and existing maintenance practices for fuel tank systems. As a result of those findings, we issued a regulation titled “Transport Airplane Fuel Tank System Design Review, Flammability Reduction and Maintenance and Inspection Requirements” (66 FR 23086, May 7, 2001). In addition to new airworthiness standards for transport airplanes and new maintenance requirements, this rule included Special Federal Aviation Regulation No. 88 (“SFAR 88,” Amendment 21-78, and subsequent Amendments 21-82 and 21-83).

Among other actions, SFAR 88 requires certain type design (i.e., type certificate (TC) and supplemental type certificate (STC)) holders to substantiate that their fuel tank systems can prevent ignition sources in the fuel tanks. This requirement applies to type design holders for large turbine-powered transport airplanes and for subsequent modifications to those airplanes. It requires them to perform design reviews and to develop design changes and maintenance procedures if their designs do not meet the new fuel tank safety standards. As explained in the preamble to the rule, we intended to adopt airworthiness directives to mandate any changes found necessary to address unsafe conditions identified as a result of these reviews.

In evaluating these design reviews, we have established four criteria intended to define the unsafe conditions associated with fuel tank systems that require corrective actions. The percentage of operating time during which fuel tanks are exposed to flammable conditions is one of these criteria. The other three criteria address the failure types under evaluation: single failures, single failures in combination with a latent condition(s), and in-service failure experience. For all four criteria, the evaluations included consideration of previous actions taken that may mitigate the need for further action.

The Joint Aviation Authorities (JAA) has issued a regulation that is similar to SFAR 88. (The JAA is an associated body of the European Civil Aviation Conference (ECAC) representing the civil aviation regulatory authorities of a number of European States who have agreed to co-operate in developing and implementing common safety regulatory standards and procedures.) Under this regulation, the JAA stated that all members of the ECAC that hold type certificates for transport category airplanes are required to conduct a design review against explosion risks.

We have determined that the actions identified in this proposed AD are necessary to reduce the potential of ignition sources inside fuel tanks, which, in combination with flammable fuel vapors, could result in fuel tank explosions and consequent loss of the airplane.

On September 13, 1999, we issued AD 99-20-01, Amendment 39-11329 (64 FR 51202, September 22, 1999). That AD requires actions intended to address an unsafe condition on the products listed above.

Since we issued AD 99-20-01, Fokker has released a new version of the flight warning computer (FWC) software. (AD 99-20-01 requires installation of an earlier version of the FWC software.) In addition, Fokker also released a new version of the software for the multifunction display unit (MFDU), which is necessary to install before the installation of the new version of the FWC software. The installation of the MFDU software depends on prior installation of a resistor in the thrust reverser indication and control system or installation of an improved thrust reverser unlock indication relay.

The European Aviation Safety Agency (EASA), which is the Technical Agent for the Member States of the European Community, has issued EASA Airworthiness Directive 2008-0090, dated May 13, 2008 (referred to after this as “the MCAI”), to correct an unsafe condition for the specified products. The MCAI states:

A recent design review has been carried out on the F28 Mark 0070/0100 fuel system in accordance with the guidelines related to FAA SFAR 88 [Special Federal Aviation Regulation No. 88] (Fuel Tank Safety Program) and JAA [Joint Aviation Authorities] INT/POL/25/12. The review revealed that under certain failure conditions, prolonged dry running of the fuel transfer pumps may result in an ignition source in the centre wing fuel tank. This condition, if not corrected, could lead to ignition of flammable fuel vapors, resulting in fuel tank explosion and consequent loss of the airplane.

To address and correct this unsafe condition, new software (version V13.55) has been developed for the Flight Warning Computer (FWC). This software update introduces a decreased time delay of the centre wing fuel tank low pressure alert from 15 minutes to 60 seconds, to stop prolonged dry running of the fuel transfer pumps.

For the reasons described above, this EASA Airworthiness Directive (AD) requires the replacement of the FWC with a modified unit, incorporating software version V13.55.

The corrective actions also include revising the airplane flight manual (AFM) to change certain indications and warnings; installing new software for the MFDU; and installing a new resistor in the thrust reverser indicator and control system, or an improved thrust reverser unlock indication relay. You may obtain further information by examining the MCAI in the AD docket.

Relevant Service Information

Fokker Services B.V. has issued Service Bulletins SBF100-31-067, Revision 1, dated April 24, 2008; SBF100-31-060, dated June 1, 2002; SBF100-78-016, dated October 1, 1999; SBF100-78-017, dated December 1, 1999; and Manual Change Notification—Operational Documentation (MCNO) F100-050, dated January 31, 2008. Honeywell has issued Service Bulletin 80-0610-31-0003, dated February 13, 2008. The actions described in the service information are intended to correct the unsafe condition identified in the MCAI.

FAA's Determination and Requirements of This Proposed AD

This product has been approved by the aviation authority of another country, and is approved for operation in the United States. Pursuant to our bilateral agreement with the State of Design Authority, we have been notified of the unsafe condition described in the MCAI and service information referenced above. We are proposing this AD because we evaluated all pertinent information and determined an unsafe condition exists and is likely to exist or develop on other products of the same type design.

Differences Between This AD and the MCAI or Service Information

We have reviewed the MCAI and related service information and, in general, agree with their substance. But we might have found it necessary to use different words from those in the MCAI to ensure the AD is clear for U.S. operators and is enforceable. In making these changes, we do not intend to differ substantively from the information provided in the MCAI and related service information.

We might also have proposed different actions in this AD from those in the MCAI in order to follow FAA policies. Any such differences are highlighted in a Note within the proposed AD.

Costs of Compliance

Based on the service information, we estimate that this proposed AD would affect about 4 products of U.S. registry.

The actions that are required by AD 99-20-01 and retained in this proposed AD take about 7 work-hours per product, at an average labor rate of $80 per work hour. Required parts cost about $1,593 per product. Based on these figures, the estimated cost of the currently required actions is $2,153 per product.

We estimate that it would take about 7 work-hours per product to comply with the new basic requirements of this proposed AD. The average labor rate is $80 per work-hour. Required parts would cost about $5,350 per product. Where the service information lists required parts costs that are covered under warranty, we have assumed that there will be no charge for these costs. As we do not control warranty coverage for affected parties, some parties may incur costs higher than estimated here. Based on these figures, we estimate the cost of the proposed AD on U.S. operators to be $23,640, or $5,910 per product.

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 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 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. 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 and placed it in the AD docket.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Incorporation by reference
• Safety

The Proposed Amendment

Accordingly, under the authority delegated to me by the Administrator, the FAA proposes to amend 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. The FAA amends § 39.13 by removing Amendment 39-11329 (64 FR 51202, September 22, 1999) and adding the following new AD:

Fokker Services B.V.: Docket No. FAA-2009-0563; Directorate Identifier 2008-NM-180-AD.

Comments Due Date

(a) We must receive comments by July 20, 2009.

Affected ADs

(b) The proposed AD supersedes AD 99-20-01, Amendment 39-11329.

Applicability

(c) This AD applies to airplanes, certificated in any category, as identified in paragraphs (c)(1) and (c)(2) of this AD.

(1) Fokker Model F.28 Mark 0100 airplanes, all serial numbers.

(2) Fokker Model F.28 Mark 0070 airplanes, serial numbers 11521, 11528 through 11537 inclusive, 11545, 11547, 11553, 11557, 11561, 11562, 11566, 11567, 11571, 11572, 11576 through 11579 inclusive, and 11581 through 11583 inclusive. All airplanes with these serial numbers are fitted with center wing fuel tanks.

Subject

(d) Air Transport Association (ATA) of America Codes 31 and 78: Instruments and Engine Exhaust, respectively.

Reason

(e) The mandatory continuing airworthiness information (MCAI) states:

A recent design review has been carried out on the F28 Mark 0070/0100 fuel system in accordance with the guidelines related to FAA SFAR 88 [Special Federal Aviation Regulation No. 88] (Fuel Tank Safety Program) and JAA [Joint Aviation Authorities] INT/POL/25/12. The review revealed that under certain failure conditions, prolonged dry running of the fuel transfer pumps may result in an ignition source in the centre wing fuel tank. This condition, if not corrected, could lead to ignition of flammable fuel vapors, resulting in fuel tank explosion and consequent loss of the airplane.

To address and correct this unsafe condition, new software (version V13.55) has been developed for the Flight Warning Computer (FWC). This software update introduces a decreased time delay of the centre wing fuel tank low pressure alert from 15 minutes to 60 seconds, to stop prolonged dry running of the fuel transfer pumps.

For the reasons described above, this EASA Airworthiness Directive (AD) requires the replacement of the FWC with a modified unit, incorporating software version V13.55.

The corrective actions also include revising the airplane flight manual (AFM) to change certain indications and warnings; installing new software for the multifunction display unit (MFDU); and installing a new resistor in the thrust reverser indicator and control system, or an improved thrust reverser unlock indication relay.

Restatement of Requirements of AD 99-20-01 With No Changes to the Modifications

Modifications

(f) Unless already done, within 18 months after October 27, 1999 (the effective date of AD 99-20-01), modify the electrical wiring of the FWC in accordance with Part 1 or 2, as applicable, of the Accomplishment Instructions of Fokker Service Bulletin SBF100-31-047, Revision 1, dated March 21, 1997.

Note 1:

It is not necessary to install computer software version V10.40 into the FWC, since a later version is available and is required to be installed by AD 99-20-01.

(g) Unless already done, concurrently with the accomplishment of the requirements of paragraph (f) of this AD, install upgraded computer software version V11.45 into the FWC in accordance with Fokker Service Bulletin SBF100-31-051, dated August 15, 1998.

Note 2:

AlliedSignal Grimes Aerospace has issued Service Bulletin 80-0610-31-0031, dated May 14, 1998, as an additional source of service information for installation of the upgraded computer software version into the FWC.

Note 3:

Operators should note that Fokker Service Bulletin SBF100-31-051, dated August 15, 1998, specifies prior or concurrent accomplishment of Fokker Service Bulletin SBF100-78-014 [which specifies concurrent accomplishment of Fokker Component Service Bulletin (CSB) P41440-78-04, and prior or concurrent accomplishment of Fokker Service Bulletin SBF100-78-012 and CSB P41440-78-05]. Related FAA AD 99-20-02, amendment 39-11330, requires accomplishment of these four other service bulletins.

New Requirements of This AD: Actions and Compliance

(h) Unless already done, do the following actions.

(1) Within 36 months after the effective date of this AD, replace FWC units having part number (P/N) 80-0610-3-45 and P/N 80-0610-3-50 with modified units having P/N 80-0610-3-55, in accordance with the Accomplishment Instructions of Fokker Service Bulletin SBF100-31-067, Revision 1, dated April 24, 2008.

(2) Within 36 months after the effective date of this AD and concurrently with the accomplishment of paragraph (h)(1) of this AD, revise the Emergency and Abnormal Procedures sections of the airplane flight manual (AFM), as specified in Fokker Manual Change Notification-Operational Documentation (MCNO) F100-050, dated January 31, 2008. These sections provide alterations, which are introduced by Fokker Service Bulletin SBF100-31-067, Revision 1, dated April 24, 2008.

Note 4:

Revisions to the Emergency Procedures and Abnormal Procedures sections of the AFM, as specified in Fokker MCNO F100-050, dated January 31, 2008, may be done by inserting copies of Fokker MCNO F100-050, dated January 31, 2008, into the AFM. When the information in Fokker MCNO F100-050, dated January 31, 2008, has been included in general revisions of the AFM, the general revisions may be inserted in the AFM, provided the relevant information in the general revision is identical to that in Fokker MCNO F100-050, dated January 31, 2008.

(3) After accomplishing paragraph (h)(1) of this AD, no person may install an FWC having P/N 80-0610-3-45 or P/N 80-0610-3-50, unless it has been modified to P/N 80-0610-3-55 standard in accordance with Honeywell Service Bulletin 80-0610-31-0003, dated February 13, 2008.

(4) Within 36 months after the effective date of this AD, install software version V12 for the MFDU in accordance with the Accomplishment Instructions of Fokker Service Bulletin SBF100-31-060, dated June 1, 2002.

(5) Within 36 months after the effective date of this AD, modify the thrust reverser indication and control system in accordance with the Accomplishment Instructions of Fokker Service Bulletin SBF100-78-016, dated October 1, 1999; or modify the thrust reverser unlock indication relay in accordance with the Accomplishment Instructions of Fokker Service Bulletin SBF100-78-017, dated December 1, 1999.

FAA AD Differences

Note 5:

This AD differs from the MCAI and/or service information as follows:

Item 1. Replacing the MFDU in accordance with Fokker Service Bulletin SBF100-31-060, dated June 1, 2002, is not included in the MCAI; however, this AD includes that action. It is necessary to install a new version of the MFDU software before installing the new version of the FWC software.

Item 2. Modifying the thrust reverser indication and control system in accordance with Fokker Service Bulletin SBF100-78-016, dated October 1, 1999; or modifying the thrust reverser unlock indication relay in accordance with Fokker Service Bulletin SBF100-78-017, dated December 1, 1999, is not included in the MCAI; however, this AD includes those actions. It is necessary to do one of those actions before installing the MFDU software.

Other FAA AD Provisions

(i) The following provisions also apply to this AD:

(1) Alternative Methods of Compliance (AMOCs): The Manager, International Branch, ANM-116, Transport Airplane Directorate, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. Send information to ATTN: Tom Rodriguez, Aerospace Engineer, International Branch, ANM-116, Transport Airplane Directorate, FAA, 1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone [phone]; fax [phone]. Before using any approved AMOC on any airplane to which the AMOC applies, notify your principal maintenance inspector (PMI) or principal avionics inspector (PAI), as appropriate, or lacking a principal inspector, your local Flight Standards District Office.

(2) Airworthy Product: For any requirement in this AD to obtain corrective actions from a manufacturer or other source, use these actions if they are FAA-approved. Corrective actions are considered FAA-approved if they are approved by the State of Design Authority (or their delegated agent). You are required to assure the product is airworthy before it is returned to service.

(3) Reporting Requirements: For any reporting requirement in this AD, under the provisions of the Paperwork Reduction Act, the Office of Management and Budget (OMB) has approved the information collection requirements and has assigned OMB Control Number 2120-0056.

Related Information

(j) Refer to MCAI European Aviation Safety Agency Airworthiness Directive 2008-0090, dated May 13, 2008, and the service information in Table 1 of this AD, for related information.

Table 1—Related Information

Service information—	Revision level—	Dated—
Fokker MCNO F100-50	Original	January 31, 2008.
Fokker Service Bulletin SBF100-31-060	Original	June 1, 2002.
Fokker Service Bulletin SBF100-31-067	Revision 1	April 24, 2008.
Fokker Service Bulletin SBF100-78-016	Original	October 1, 1999.
Fokker Service Bulletin SBF100-78-017	Original	December 1, 1999.
Honeywell Service Bulletin 80-0610-31-0003	Original	February 13, 2008.

Issued in Renton, Washington, on June 11, 2009.

Ali Bahrami,

Manager, Transport Airplane Directorate, Aircraft Certification Service.