E6-17327. Airworthiness Directives; Pratt & Whitney JT8D-1, -1A, -1B, -7, -7A, -7B, -9, -9A, -11, -15, -15A, -17, -17A, -17R, -17AR, -209, -217, -217A, -217C, and -219 Turbofan Engines

AGENCY:

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

ACTION:

Final rule; correction.

SUMMARY:

The FAA is revising an existing airworthiness directive (AD) for Pratt & Whitney (PW) JT8D-1, -1A, -1B, -7, -7A, -7B, -9, -9A, -11, -15, -15A, -17, -17A, -17R, -17AR, -209, -217, -217A, -217C, and -219 turbofan engines. That AD currently requires either replacing high pressure compressor (HPC) front hubs and HPC disks that have operated at any time with PWA 110-21 coating and that operated in certain engine models, or, visually inspecting and fluorescent penetrant inspecting (FMPI) for cracking of those parts and re-plating them if they pass inspection. This AD requires the same actions, but makes necessary corrections to inadvertent reference errors and omissions found in AD 2006-17-07, and relaxes some of the compliance times in Table 5. This AD results from our finding reference errors and omissions in AD 2006-17-07, from determining that the AD as drafted imposed an unnecessary burden on operators if they have to immediately remove engines, and from requests to clarify compliance paragraphs. We are issuing this AD to prevent a rupture of an HPC front hub or an HPC disk that could result in an uncontained engine failure and damage to the airplane.

DATES:

This AD becomes effective November 2, 2006. The Director of the Federal Register previously approved the incorporation by reference of certain publications listed in the regulations as of October 4, 2006 (71 FR 51459, August 30, 2006).

ADDRESSES:

You can get the service information identified in this AD from Pratt & Whitney, 400 Main St., East Hartford, CT 06108, telephone [phone]; fax [phone].

You may examine the AD docket on the Internet at http://dms.dot.gov or in Room PL-401 on the plaza level of the Nassif Building, 400 Seventh Street, SW., Washington, DC.

FOR FURTHER INFORMATION CONTACT:

Keith Lardie, Aerospace Engineer, Engine Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803; telephone [phone]; fax [phone].

SUPPLEMENTARY INFORMATION:

On August 21, 2006, the FAA issued AD 2006-17-07, Amendment 39-14728 (71 FR 51459, August 30, 2006). That AD requires either replacing HPC front hubs and HPC disks that have operated at any time with PWA 110-21 coating and that operated in certain engine models, or, visually inspecting and FMPI for cracking of those parts and re-plating them if they pass inspection. That AD was the result of an investigation by PW, which concluded that any HPC front hub or HPC disk coated with PWA 110-21 that ever operated on JT8D-15, -15A, -17, -17A, -17R, -17AR, -209, -217, -217A, -217C, and -219 turbofan engines, could crack before reaching their published life limit. That condition, if not corrected, could result in an uncontained engine failure and damage to the airplane.

Examining the AD Docket

You may examine the docket that contains the AD, any comments received, and any final disposition in person at the Docket Management Facility Docket Office between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The Docket Office (telephone [phone]) is located on the plaza level of the Department of Transportation Nassif Building at the street address stated in ADDRESSES. Comments will be available in the AD docket shortly after the DMS receives them.

Actions Since AD 2006-17-07 Was Issued

After we issued AD 2006-17-07, we found reference errors and omissions. These errors and omissions could affect your ability to comply with the AD. The following errors and omissions were discovered. We made the associated corrections:

• In the third column of Table 1 of this AD, we omitted “-17A” in two places. We added the missing “-17A” from AD 2006-17-07 in both places.
• The third column of Table 4 and Table 5 reads “Paragraph (h)(3) of this AD”. Paragraph (h)(3) does not exist. We corrected it to read “Paragraph (j) of this AD.”

We also determined that based on the compliance times in Table 5 of AD 2006-17-07, some operators might have to immediately remove their engines from service. If so, we concluded that those immediate removals might impose an unanticipated undue burden. Table 5 of AD 2006-17-07, appears below.

 Table 5 of AD 2006-17-07—HPC Front Hub Inspection Schedule—Hubs Coated With Nickel-Cadmium

HPC front hub CSN on the effective date of this AD	Inspect before additional CIS or CSN, whichever occurs first	Also inspect 7th stage HPC disks and 9th stage-through-12th stage HPC disks using:
(i) 19,000 or more	500 CIS or 20,000 CSN	Paragraph (h)(3) of this AD.
(ii) 17,000 or more, but fewer than 19,000	1,000 CIS or 19,500 CSN	Paragraph (h)(3) of this AD.
(iii) 9,000 or more, but fewer than 17,000, that have not been inspected	18,000 CSN	Paragraph (h)(3) of this AD.
(iv) 9,000 or more, but fewer than 17,000, that were inspected before accumulating 9,000 CSN	15,500 CSN	Paragraph (h)(3) of this AD.

Therefore, we changed Table 5 to reflect relaxed compliance requirements in item (iii), and we changed the compliance requirements in item (iv). With the addition of the “-17A” noted previously, and the changed compliance requirements that relax compliance time, Table 5 now reads as follows:

 (Changed) Table 5.—HPC Front Hub Inspection Schedule—Hubs Coated With Nickel-Cadmium

HPC front hub CSN on the effective date of this AD	Inspect before additional CIS or CSN, whichever occurs first	Also inspect 7th stage HPC disks and 9th stage-through-12th stage HPC disks using:
(i) 19,000 or more	500 CIS or 20,000 CSN	Paragraph (j) of this AD.
(ii) 17,000 or more, but fewer than 19,000	1,000 CIS or 19,500 CSN	Paragraph (j) of this AD.
(iii) 9,000 or more, but fewer than 17,000	18,000 CSN	Paragraph (j) of this AD.
(iv) Fewer than 9,000 that are accessible	If the parts have been inspected and are acceptable, parts may be reinstalled. Inspect again using the criteria in (iii) of this table	Paragraph (j) of this AD.

As part of relaxing the requirements, we also clarified that paragraphs (f)(3) and (j) pertain to 7th stage HPC disks and 9th stage-through-12th stage HPC disks coated with PWA 110-21.

Finally, since AD 2006-17-07 was issued, we received multiple instances of operators requesting clarification of compliance paragraph (e) in AD 2006-17-07. Based on the frequency of requests, we decided to clarify the paragraph. AD 2006-17-07 paragraph (e) originally read as follows:

``(e) You must accomplish the actions required by this AD within the compliance times specified, unless the actions have already been done. Any engine with an HPC front hub that has been inspected using AD 2002-23-14, AD 2003-12-07, or AD 2003-16-05, is considered in compliance with this AD.”

We rewrote paragraph (e) to now read as follows:

“(e) You must accomplish the actions required by this AD within the compliance times specified, unless the actions have already been done. Any engine with an HPC front hub that has been inspected for fretting wear using AD 2002-23-14, AD 2003-12-07, or AD 2003-16-05, counts as an inspection toward compliance with this AD.”

FAA's Determination and Requirements of This AD

The unsafe condition described previously is likely to exist or develop on other Pratt & Whitney JT8D-1, -1A, -1B, -7, -7A, -7B, -9, -9A, -11, -15, -15A, -17, -17A, -17R, -17AR, -209, -217, -217A, -217C, and -219 turbofan engines of the same type design. We are issuing this AD to prevent a rupture of an HPC front hub or an HPC disk that could result in an uncontained engine failure and damage to the airplane. This AD requires either replacing HPC front hubs and HPC disks that have operated at any time with PWA 110-21 coating and that operated in certain engine models, or, visually inspecting and FMPI for cracking of those parts and re-plating them if they pass inspection.

FAA's Determination of the Effective Date

Since an unsafe condition exists that requires the immediate adoption of this AD, we have found that notice and opportunity for public comment before issuing this AD are unnecessary, and that good cause exists for making this amendment effective in less than 30 days.

Docket Number Change

We are transferring the docket for this AD to the Docket Management System as part of our on-going docket management consolidation efforts. The new Docket No. is FAA-2006-25809. The old Docket No. became the Directorate Identifier, which is 2001-NE-30-AD. This AD might get logged into the DMS docket, ahead of the previously collected documents from the old docket file, as we are in the process of sending those items to the DMS.

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 AD will not have federalism implications under Executive Order 13132. This AD will 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 this AD:

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

(2) Is not a “significant rule” under 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 summary of the costs to comply with this AD and placed it in the AD Docket. 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
• Incorporation by reference
• Safety

Adoption of the Amendment

Under the authority delegated to me by the Administrator, the Federal Aviation Administration amends 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

[Amended]

2. The FAA amends § 39.13 by removing Amendment 39-14728 ( 71 FR 51459, August 30, 2006), and by adding a new airworthiness directive, Amendment 39-14791, to read as follows:

2006-17-07R1 Pratt & Whitney: Amendment 39-14791. Docket No. FAA-2006-25809; Directorate Identifier 2001-NE-30-AD.

Effective Date

(a) This airworthiness directive (AD) becomes effective November 2, 2006.

Affected ADs

(b) This AD revises AD 2006-17-07.

Applicability

(c) This AD applies to the following Pratt & Whitney (PW) JT8D-1, -1A, -1B, -7, -7A, -7B, -9, -9A, -11, -15, -15A, -17, -17A, -17R, -17AR, -209, -217, -217A, -217C, and -219 turbofan engines, with 8th stage high pressure compressor (HPC) front hubs:

Table 1.—AD Applicability

If the HPC front hub is coated with:	And if the stage 8-9 spacer is coated with:	And the HPC front hub:	Then this AD is:
(1) PWA 110-21 at any time	Any	Operated in a JT8D-15, -15A, -17, -17A, -17R, or -17AR engine	Applicable. See paragraph (f) and Table 2 of this AD.
(2) PWA 110-21 at any time	Any	Operated in a JT8D-209, -217, -217A, -217C, or -219 engine	Applicable. See paragraph (h) and Table 4 of this AD.
(3) Nickel-Cadmium	PWA 110-21 at any time	Operated in a JT8D-209, -217, -217A, -217C, or -219 engine	Applicable. See paragraph (i) and Table 5 of this AD.
(4) Nickel-Cadmium	PWA 110-21 at any time	Operated in a JT8D-1, -1A, -1B, -7, -7A, -7B, -9, -9A, -11, -15, -15A, -17, -17A, -17R, or -17AR engine	Not applicable.
(5) PWA 110-21 at any time	Any	Operated in a JT8D-1, -1A, -1B, -7, -7A, -7B, -9, -9A, or -11, but never operated in a JT8D-15, -15A, -17, -17A, -17R, -17AR, -209, -217, -217A, -217C, or -219 engine	Not applicable.
(6) Nickel-Cadmium	Any type but PWA 110-21	Any	Not applicable.

These engines are installed on, but not limited to, Boeing DC-9, MD-80 series, 727 series, and 737 series airplanes.

Unsafe Condition

(d) This AD results from inadvertent reference errors and omissions found in AD 2006-17-07, which could affect ability to comply with that AD. We are issuing this AD to prevent a rupture of an HPC front hub or an HPC disk that could result in an uncontained engine failure and damage to the airplane.

Compliance

(e) You must accomplish the actions required by this AD within the compliance times specified, unless the actions have already been done. Any engine with an HPC front hub that has been inspected for fretting wear using AD 2002-23-14, AD 2003-12-07, or AD 2003-16-05, counts as an inspection toward compliance with this AD.

JT8D-1, -1A, -1B, -7, -7A, -7B, -9, -9A, -11, -15, -15A, -17, -17A, -17R, and -17AR Turbofan Engines—Inspect or Replace HPC Front Hubs, HPC Disks, and Stage 8-9 Spacers

(f) For applicable JT8D-1, -1A, -1B, -7, -7A, -7B, -9, -9A, -11, -15, -15A, -17, -17A, -17R, and -17AR turbofan engines specified in Table 1 of this AD, do the following:

(1) Using the inspection schedule in Table 2 of this AD, strip the protective coating, visually inspect for fretting wear, fluorescent magnetic particle inspect (FMPI) for cracks, reidentify, replate HPC front hubs and stage 8-9 spacers, and replace if necessary.

(2) Use paragraphs 1. through 3.B.(7)(b) under “For Rear Compressor Front Hubs that Have Operated With PWA 110-21 coating AT ANY TIME During Their Service Life in JT8D-15, -15A, -17, -17A, -17R, -17AR Engine Models.” of PW Alert Service Bulletin (ASB) JT8D A6468, dated December 23, 2004.

Table 2.—HPC Front Hub Inspection Schedule

HPC front hub cycles-since-new (CSN) on the effective date of this AD	Inspect before additional cycles-in-service (CIS) or CSN, whichever occurs first	Also inspect 7th stage HPC disks and 9th stage-through-12th stage HPC disks using:
(i) 19,000 or more	500 CIS or 20,000 CSN	Paragraph (f)(3) of this AD.
(ii) 15,500 or more, but fewer than 19,000	1,000 CIS or 19,500 CSN	Paragraph (f)(3) of this AD.
(iii) 5,000 or more, but fewer than 15,500	16,500 CSN	Paragraph (f)(3) of this AD.
(iv) Fewer than 5,000 that are accessible	If the parts have been inspected and are acceptable, parts may be reinstalled. Inspect again using the criteria in (iii) of this Table	Paragraph (f)(3) of this AD.

(3) When the HPC front hub is inspected, visually inspect for fretting wear and FMPI for cracks on 7th stage HPC disks and 9th stage-through-12th stage HPC disks coated with PWA 110-21. Inspection information can be found in the applicable sections of JT8D Engine Manual Part Number (P/N) 481672, listed in the following Table 3:

Table 3.—Seventh Stage HPC Disks and 9th Stage-Through-12th Stage HPC Disks Inspection Information

Stage	Chapter/ section	Visual inspection	Fretting inspection	FMPI
7	72-36-41	Inspection-01	Inspection-04	Inspection-03.
9	72-36-43	Inspection-01	Inspection-04	Inspection-03.
10	72-36-44	Inspection-01	Inspection-04	Inspection-03.
11	72-36-45	Inspection-01	Inspection-04	Inspection-03.
12	72-36-46	Inspection-01	Inspection-04	Inspection-03.

JT8D-15, -15A, -17, -17A, -17R, and -17AR Turbofan Engines—Cycle Adjustment for HPC Front Hubs That Entered Service With Nickel-Cadmium Plating and PWA 110-21 Coating

(g) For JT8D-15, -15A, -17, -17A, -17R, and -17AR turbofan engines with front hubs that entered service with Nickel-Cadmium plating, but have also operated during the life of the hub with PWA 110-21 coating:

(1) You are allowed to make a cycle adjustment if the hub was never operated with a PWA 110-21-coated stage 8-9 spacer.

(2) Use the information under “Compliance” of PW ASB JT8D A6468, dated December 23, 2004, to determine the adjustment.

JT8D-209, -217, -217A, -217C, and -219 Turbofan Engines—Inspect or Replace HPC Front Hubs and Stage 8-9 Spacers

(h) For applicable JT8D-209, -217, -217A, -217C, and -219 turbofan engines specified in Table 1, Row (2) of this AD, do the following:

(1) Using the inspection schedule in Table 4 of this AD, strip the protective coating, visually inspect for fretting wear, FMPI for cracking, reidentify, replate HPC front hubs and the stage 8-9 spacers, and replace if necessary.

(2) Use paragraphs 1. through 1.A. and paragraphs 2. through 2.C.(2)(g)2 of Accomplishment Instructions of PW ASB JT8D A6430, Revision 2, dated December 23, 2004.

Table 4.—HPC Front Hub Inspection Schedule—Hubs Coated With PWA 110-21

HPC front hub CSN on the effective date of this AD	Inspect before additional CIS or CSN, whichever occurs first	Also inspect 7th stage HPC disks and 9th stage-through-12th stage HPC disks using:
(i) 19,000 or more	500 CIS or 20,000 CSN	Paragraph (j) of this AD.
(ii) 15,500 or more, but fewer than 19,000	1,000 CIS or 19,500 CSN	Paragraph (j) of this AD.
(iii) 5,000 or more, but fewer than 15,500	16,500 CSN	Paragraph (j) of this AD.
(iv) Fewer than 5,000 that are accessible.	If the parts have been inspected and are acceptable, parts may be reinstalled. Inspect again using the criteria in (iii) of this Table	Paragraph (j) of this AD.

(i) For applicable JT8D-209, -217, -217A, -217C, and -219 turbofan engines specified in Table 1, Row (3) of this AD, do the following:

(1) Using the inspection schedule in Table 5 of this AD, strip the protective coating, visually inspect for fretting wear, FMPI for cracking, reidentify, replate HPC front hubs and the stage 8-9 spacers, and replace if necessary.

(2) Use paragraphs 1., 1.C, and 4. through 4.B.(2)(g)2 of Accomplishment Instructions of PW ASB JT8D A6430, Revision 2, dated December 23, 2004, for all applicable hubs with any type of coating.

Table 5.—HPC Front Hub Inspection Schedule—Hubs Coated With Nickel-Cadmium

HPC front hub CSN on the effective date of this AD	Inspect before additional CIS or CSN, whichever occurs first	Also inspect 7th stage HPC disks and 9th stage-through-12th stage HPC disks using:
(i) 19,000 or more	500 CIS or 20,000 CSN	Paragraph (j) of this AD.
(ii) 17,000 or more, but fewer than 19,000	1,000 CIS or 19,500 CSN	Paragraph (j) of this AD.
(iii) 9,000 or more, but fewer than 17,000	18,000 CSN	Paragraph (j) of this AD.
(iv) Fewer than 9,000 that are accessible	If the parts have been inspected and are acceptable, parts may be reinstalled. Inspect again using the criteria in (iii) of this Table	Paragraph (j) of this AD.

(j) When the HPC front hub is inspected, visually inspect for fretting wear and FMPI for cracks on 7th stage HPC disks and 9th stage-through-12th stage HPC disks coated with PWA 110-21. Inspection information can be found in the applicable sections of JT8D-200 Engine Manual P/N 773128, listed in Table 3 of this AD.

JT8D-209, -217, -217A, -217C, and -219 Turbofan Engines—Cycle Adjustment for HPC Front Hubs That Entered Service With Nickel-Cadmium Plating and PWA 110-21 Coating

(k) For JT8D-209, -217, -217A, -217C, and -219 turbofan engines with HPC front hubs that entered service with Nickel-Cadmium plating, but have also operated during the life of the hub with PWA 110-21 coating:

(1) You are allowed to make a cycle adjustment.

(2) Use the information under “CONDITION A” of PW ASB JT8D A6430, Revision 2, dated December 23, 2004, to determine the adjustment.

Replacement of HPC Front Hubs and Stage 8-9 Spacers That Have Operated With PWA 110-21 Coating, As Optional Action—All Engines

(l) For all applicable engines, as an optional action for the visual inspections in this AD, replace HPC front hubs and stage 8-9 spacers that have operated with PWA 110-21 coating in the interface between the hub and the stage 8-9 spacer and HPC disks currently coated with PWA 110-21, as follows:

(1) Install a Nickel-Cadmium plated HPC front hub that has never operated with PWA 110-21 coating in the interface between the HPC front hub and the stage 8-9 spacer.

(2) Install a Nickel-Cadmium plated or Electroless Nickel-plated stage 8-9 spacer.

(3) Install HPC disks that have never operated with PWA 110-21 coating.

Prohibition Against Recoating the HPC Front Hub, Stage 7 HPC Disk, and Stage 8-9 Spacer With PWA 110-21—All Engines

(m) Do not recoat the HPC front hub with PWA 110-21 (Repair-23 of Chapter/Section 72-36-42 of JT8D-200 Engine Manual, P/N 773128, and Repair-27 and Repair-28 of Chapter/Section 72-36-42 of JT8D Engine Manual, P/N 481672).

(n) Do not recoat the 7th stage disk with PWA 110-21 (Repair-15 of Chapter/Section 72-36-41 of JT8D-200 Engine Manual, P/N 773128, and Repair-15 of Chapter/Section 72-36-41 of JT8D Engine Manual, P/N 481672).

(o) Do not recoat the stage 8-9 spacer with PWA 110-21 (Repair-03, Task 72-36-12-30-003-002, of Chapter/Section 72-36-12 of JT8D-200 Engine Manual, P/N 773128, and Repair-01, Task 72-36-12-30-001-002, of Chapter/Section 72-36-12 of JT8D Engine Manual, P/N 481672).

Prohibition Against Reinstalling HPC Front Hubs and Stage 8-9 Spacers Coated With PWA 110-21

(p) After the effective date of this AD, do not reinstall HPC front hubs and stage 8-9 spacers coated with PWA 110-21.

Definition

(q) For the purpose of this AD, “accessible” is defined as when the HPC front hub is removed from the engine and the hub is debladed.

Alternative Methods of Compliance

(r) 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

(s) None.

Material Incorporated by Reference

(t) You must use the service information specified in Table 6 of this AD to perform the actions required by this AD. The Director of the Federal Register previously approved the incorporation by reference of these alert service bulletins in accordance with 5 U.S.C. 552(a) and 1 CFR part 51, as of October 4, 2006 (71 FR 51459, August 30, 2006). Contact Pratt & Whitney, 400 Main St., East Hartford, CT 06108, telephone [phone]; fax [phone] for a copy of this service information. You may review copies at the FAA, New England Region, Office of the Regional Counsel, 12 New England Executive Park, Burlington, MA; or at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call 202-741-6030, or go to: http://www.archives.gov/​federal-register/​cfr/​ibr-locations.html.

Table 6.—Incorporation by Reference

Pratt & Whitney Alert Service Bulletin No.	Page	Revision	Date
JT8D A6430, Total Pages: 35	ALL	2	December 23, 2004.
JT8D A6468, Total Pages: 20	ALL	Original	December 23, 2004.

Issued in Burlington, Massachusetts, on October 11, 2006.

Thomas A. Boudreau,

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