E7-13256. Airworthiness Directives; International Aero Engines AG (IAE) V2500 Series Turbofan Engines

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 IAE V2500-A1, V2522-A5, V2524-A5, V2527-A5, V2527E-A5, V2527M-A5, V2530-A5, V2533-A5, V2525-D5, V2528-D5 turbofan engines. This proposed AD would require removing certain No. 4 bearing seal components from service at the next shop visit or by an end date determined by the engine model. This proposed AD results from instances of oil loss from the No. 4 bearing compartment. We are proposing this AD to prevent heat damage to high pressure turbine (HPT) and low pressure turbine (LPT) critical life limited hardware such as the HPT stage 1-2 airseal. Damage to the HPT stage 1-2 airseal could cause uncontained engine failure and damage to the airplane.

DATES:

We must receive any comments on this proposed AD by September 7, 2007.

ADDRESSES:

Use one of the following addresses to comment 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: 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: Deliver to Mail address above between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.
• Fax: [phone].

FOR FURTHER INFORMATION CONTACT:

Colleen M. D'Alessandro, Aerospace Engineer, Engine Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803; telephone [phone]; fax [phone].

SUPPLEMENTARY INFORMATION:

Comments Invited

We invite you to send us any written relevant data, views, or arguments regarding this proposal. Send your comments to an address listed under ADDRESSES. Include “Docket No. FAA-2007-28058; Directorate Identifier 2007-NE-08-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 received 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://dms.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 the DOT 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 may review the DOT's complete Privacy Act Statement in the Federal Register published on April 11, 2000 (65 FR 19477-78) or you may visit http://dms.dot.gov.

Examining the AD Docket

You may examine the AD docket on the Internet at http://dms.dot.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 the same as the Mail address provided in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt.

Discussion

Between March 1993 and October 2006, we received reports of 24 confirmed instances of oil loss from the No. 4 bearing compartment. Each instance resulted in the oil igniting and caused heat distress damage to HPT and LPT hardware.

International Aero Engines (IAE) attributes the oil loss to two root causes, fractures of the rear No. 4 carbon seal and insufficient oil scavenging. The fractures result from fracture of the HPT stage 1 disk metering plug due to high-cycle fatigue (HCF). Industry confirms five instances of fractured metering plugs between January 2001 and October 2006. Regarding the insufficient oil scavenging, Industry confirms 19 instances of distress of the HPT, the LPT, or both, caused by oil flooding the No. 4 bearing compartment between March 1993, and October 2006.

We have monitored industry's investigation, field actions, and service experience with this problem. However, we conclude that proposed corrective actions are inadequate. These conditions, if not corrected, could result in heat damage to critical life limited hardware such as the HPT stage 1-2 airseal. Damage to the HPT stage 1-2 airseal could cause uncontained engine failure, and damage to the airplane.

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 products of this same type design. We are proposing this AD, which would require removing the parts specified in this proposed AD at the next shop visit, but no later than November 2008 for the V2500-A1 model or June 2011 for the—A5 and -D5 models.

Costs of Compliance

We estimate that this proposed AD would affect 686 engines installed on airplanes of U.S. registry. Of those 686 engines, the operators of nineteen V2500-A1 engines, thirty -A5 engines and twenty-one -D5 engines have already complied with the requirements in the proposed AD.

Costs of Compliance per year by Engine Model

Engine Model	Number of engines per year	Total labor cost per year	Total parts cost per year	Total cost per year
V2500-A1	33	$355,080	$7,230,564	$7,585,644
V2522-A5, V2524-A5, V2527-A5, V2527E-A5, V2527M-A5, V2530-A5, V2533-A5	142	1,368,880	35,790,816	37,159,696
V2525-D5, V2528-D5	5	15,400	276,425	291,825

Based on these figures, we estimate the total cost of the proposed AD to U.S. operators to be $45,037,165 per year.

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 AD:

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. Would 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. You may get a copy of this summary at the address listed under ADDRESSES.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Safety

The Proposed Amendment

Under the authority delegated to me by the Administrator, the Federal Aviation Administration 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 adding the following new airworthiness directive:

International Aero Engines AG (IAE): Docket No. FAA-2007-28058; Directorate Identifier 2007-NE-08-AD.

Comments Due Date

(a) The Federal Aviation Administration (FAA) must receive comments on this airworthiness directive (AD) action by September 7, 2007.

Affected ADs

(b) None.

Applicability

(c) This AD applies to IAE V2500-A1, V2522-A5, V2524-A5, V2527-A5, V2527E-A5, V2527M-A5, V2530-A5, V2533-A5, V2525-D5, V2528-D5 turbofan engines with a part listed by part number (P/N) in this AD installed. These engines are installed on, but not limited to, Airbus A319, A320, A321, and Boeing MD-90 airplanes.

Unsafe Condition

(d) This proposed AD results from instances of oil loss from the No. 4 bearing compartment. We are issuing this AD to prevent heat damage to high pressure turbine (HPT) and low pressure turbine (LPT) critical life limited hardware such as the HPT stage 1-2 airseal. Damage to the HPT stage 1-2 airseal could cause uncontained engine failure, and damage to the airplane.

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.

V2500-A1 Engines

(f) For V2500-A1 engines, remove the parts listed by P/N in the following Table 1 of this AD at the next shop visit after the effective date of this AD but not later than November 30, 2008. The ATA chapter reference of the IAE V2500-A1 engine manual (E-V2500-1IA) contains information on removing the parts.

Table 1.—V2500-A1 Parts To Be Removed

ATA chapter reference	P/N	Nomenclature
72-42-20	2A0367-01	Tube Assy of, Weep, No. 4 Bearing Outer.
72-42-20	2A2873-01	Tube Assy of, Weep, No. 4 Bearing Outer.
72-42-20	2A0830-01	Tube, Scavenge, No. 4 Bearing Assy.
72-42-20	2A1949-01	Tube, Scavenge, No. 4 Bearing Assy.
72-42-20	2A2028-01	Tube, Scavenge, No. 4 Bearing Assy.
72-42-20	2A0830-001	Tube, Scavenge, No. 4 Bearing Assy.
72-42-20	2A2274-01	Tube, Scavenge, No. 4 Bearing Assy.
72-42-33	2A0853	Seal Assy, No. 4 Bearing, Front.
72-42-33	2A2055	Seal Assy, No. 4 Bearing, Front.
72-42-33	2A2834	Seal Assy, No. 4 Bearing, Front.
72-42-33	2A2930	Seal Assy, No. 4 Bearing, Front.
72-42-33	2A3525	Seal Assy, No. 4 Bearing, Front.
72-42-33	2A3538	Seal Assy, No. 4 Bearing, Front.
72-42-33	2A0851	Support Assy, No. 4 Bearing Seal.
72-42-33	2A2833	Support, No. 4 Bearing, Seal Assy.
72-42-33	2A3537	Support, No. 4 Bearing Seal Assy.
72-42-35	2A0892-01	Duct Assy, Cooling Air, No. 4 Bearing, Front.
72-42-35	2A2257-01	Duct Assy, Cooling Air, No. 4 Bearing, Front.
72-43-20	2A2056	Seal Assy, No. 4 Bearing, Rear.
72-43-20	2A2931	Seal Assy, No. 4 Bearing, Rear.
72-43-20	2A3526	Seal Assy, No. 4 Bearing, Rear.
72-43-20	2A0847	Seal Ring Holder.
72-43-20	2A0891-01	Duct Assy, Cooling Air, No. 4 Bearing, Rear.
72-43-20	2A1205-01	Duct Assy, Cooling Air, No. 4 Bearing, Rear.
72-43-20	2A3078-01	Duct Assy, Cooling Air, No. 4 Bearing, Rear.
72-45-11	2A0594	Metering Plug, HPT Hub, Stage 1.
72-45-11	2A1040	Metering Plug, HPT Hub, Stage 1.
72-45-11	2A2181	Metering Plug, HPT Hub, Stage 1.
72-45-13	2A0884	Seal Air, HPT Stage 1.
72-45-13	2A1203	Seal Air, HPT Stage 1.
72-45-13	2A0884-001	Seal Air, HPT Stage 1.
79-22-49	5R8111	Tube A/O Oil—No. 4 Brg Scav Dif Case to Bif Panel.
79-22-49	5R8138	Tube A/O Oil—No. 4 Brg Scav Dif Case to Bif Panel.
79-22-49	6A5367	Tube A/O Oil—No. 4 Brg Scav Dif Case to Bif Panel.
79-22-49	5A9083	Tube A/O Oil—No. 4 Brg Discon to Discon.
79-22-49	5A9084	Tube A/O Oil—No. 4 Brg Discon to Scav Valve.
79-22-49	5A8573	Tube A/O Oil—Press ‘T’ To Pressurre Transducer.
79-23-51	1648MK2	Scavenge Valve.

V2522-A5, V2524-A5, V2527-A5, V2527E-A5, V2527M-A5, V2530-A5, and V2533-A5 Engines

(g) For V2522-A5, V2524-A5, V2527-A5, V2527E-A5, V2527M-A5, V2530-A5, and V2533-A5 engines, remove the parts listed by P/N in the following Table 2 of this AD at the next shop visit after the effective date of this AD but not later than June 30, 2011. The ATA chapter reference of the IAE V2500-A5 engine manual (E-V2500-1IA) contains information on removing the parts.

Table 2.—V2522-A5, V2524-A5, V2527-A5, V2527E-A5, V2527M-A5, V2530-A5, and V2533-A5 Parts To Be Removed

ATA chapter reference	P/N	Nomenclature
72-42-20	2A0367-01	Tube Assy of, Weep, No. 4 Bearing Outer.
72-42-20	2A2873-01	Tube Assy of, Weep, No. 4 Bearing Outer.
72-42-20	2A0830-01	Tube, Scavenge, No. 4 Bearing Assy.
72-42-20	2A1949-01	Tube, Scavenge, No. 4 Bearing Assy.
72-42-33	2A0853	Seal Assy, No. 4 Bearing, Front.
72-42-33	2A2834	Seal Assy, No. 4 Bearing, Front.
72-42-33	2A2930	Seal Assy, No. 4 Bearing, Front.
72-42-33	2A3525	Seal Assy, No. 4 Bearing, Front.
72-42-33	2A3538	Seal Assy, No. 4 Bearing, Front.
72-42-33	2A0851	Support Assy, No. 4 Bearing Seal.
72-42-33	2A2833	Support, No. 4 Bearing, Seal Assy.
72-42-33	2A3537	Support, No. 4 Bearing Seal Assy.
72-42-35	2A0892-01	Duct Assy, Cooling Air, No. 4 Bearing, Front.
72-42-35	2A2257-01	Duct Assy, Cooling Air, No. 4 Bearing, Front.
72-43-20	2A2056	Seal Assy, No. 4 Bearing, Rear.
72-43-20	2A2931	Seal Assy, No. 4 Bearing, Rear.
72-43-20	2A3526	Seal Assy, No. 4 Bearing, Rear.
72-43-20	2A0847	Seal Ring Holder.
72-43-20	2A0891-01	Duct Assy, Cooling Air, No. 4 Bearing, Rear.
72-43-20	2A1205-01	Duct Assy, Cooling Air, No. 4 Bearing, Rear.
72-43-20	2A3078-01	Duct Assy, Cooling Air, No. 4 Bearing, Rear.
72-45-11	2A0594	Metering Plug, HPT Hub, Stage 1.
72-45-11	2A1040	Metering Plug, HPT Hub, Stage 1.
72-45-11	2A2354	Metering Plug, HPT Hub, Stage 1.
72-45-11	2A3182	Metering Plug, HPT Hub, Stage 1.
72-45-13	2A1352	Seal Air, HPT Stage 1.
72-45-13	2A3032	Seal Air, HPT Stage 1.
79-22-49	5R8111	Tube A/O Oil—No. 4 Brg Scav Dif Case to Bif Panel.
79-22-49	5R8138	Tube A/O Oil—No. 4 Brg Scav Dif Case to Bif Panel.
79-22-49	6A5367	Tube A/O Oil—No. 4 Brg Scav Dif Case to Bif Panel.
79-22-49	5A9083	Tube A/O Oil—No. 4 Brg Discon to Discon.
79-22-49	5A9084	Tube A/O Oil—No. 4 Brg Discon to Scav Valve.
79-22-49	5A8573	Tube A/O Oil—Press ‘T’ To Pressure Transducer.

(h) For V2522-A5, V2524-A5, V2527-A5, V2527E-A5, V2527M-A5, V2530-A5, and V2533-A5 engines with high pressure turbine (HPT) stage 1 rotor assembly, P/Ns 2A9521-002 and 2A9621-002, the stage 1 HPT hub metering plug, P/N 2A3182, does not need to be removed.

V2525-D5 and V2528-D5 Engines

(i) For V2525-D5 and V2528-D5 engines, remove the parts listed by P/N in the following Table 3 of this AD at the next shop visit after the effective date of this AD but not later than June 30, 2011. The ATA chapter reference of the IAE V2500-D5 engine manual (E-V2500-3IA) contains information on removing the parts.

Table 3.—V2525-D5 and V2528-D5 Parts to be Removed

ATA chapter reference	P/N	Nomenclature
72-42-20	2A0367-01	Tube Assy of, Weep, No. 4 Bearing Outer.
72-42-20	2A2873-01	Tube Assy of, Weep, No. 4 Bearing Outer.
72-42-33	2A0851	Support Assy, No. 4 Bearing Seal.
72-42-33	2A2833	Support, No. 4 Bearing, Seal Assy.
72-42-33	2A3537	Support, No. 4 Bearing Seal Assy.
72-42-33	2A2834	Seal Assy, No. 4 Bearing, Front.
72-42-33	2A2930	Seal Assy, No. 4 Bearing, Front.
72-42-33	2A3525	Seal Assy, No. 4 Bearing, Front.
72-42-33	2A3538	Seal Assy, No. 4 Bearing, Front.
72-42-35	2A2257-01	Duct Assy, Cooling Air, No. 4 Bearing, Front.
72-43-20	2A2056	Seal Assy, No. 4 Bearing, Rear.
72-43-20	2A2931	Seal Assy, No. 4 Bearing, Rear.
72-43-20	2A3526	Seal Assy, No. 4 Bearing, Rear.
72-43-20	2A0847	Seal Ring Holder.
72-43-20	2A1205-01	Duct Assy, Cooling Air, No. 4 Bearing, Rear.
72-43-20	2A3078-01	Duct Assy, Cooling Air, No. 4 Bearing, Rear.
72-45-11	2A3182	Metering Plug, HPT Hub, Stage 1.
72-45-11	2A2354	Metering Plug, HPT Hub, Stage 1.
72-45-13	2A1352	Seal Air, HPT Stage 1.
72-45-13	2A3032	Seal Air, HPT Stage 1.

All Engines

(j) After the effective date of this AD, do not install any part that has a P/N listed in this AD.

Alternative Methods of Compliance

(k) The Manager, Engine Certification Office, has the authority to approve alternative methods of compliance for this AD if requested using the procedures found in 14 CFR 39.19.

Related Information

(l) International Aero Engines non-modification Service Bulletin No. V2500-ENG-72-0541, Revision 1, dated February 26, 2007, pertains to the subject of this AD.

Issued in Burlington, Massachusetts, on July 2, 2007.

Peter A. White,

Acting Manager, Engine and Propeller Directorate, Aircraft Certification Service.