This section of the FEDERAL REGISTER

contains regulatory documents having general

applicability and legal effect, most of which

are keyed to and codified in the Code of

Federal Regulations, which is published under

50 titles pursuant to 44 U.S.C. 1510.

The Code of Federal Regulations is sold by

the Superintendent of Documents. Prices of

new books are listed in the first FEDERAL

REGISTER issue of each week.

Rules and Regulations Federal Register

6663 

Vol. 77, No. 27 

Thursday, February 9, 2012 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 39 

[Docket No. FAA–2011–1128; Directorate 

Identifier 2011–CE–031–AD; Amendment 

39–16933; AD 2012–02–10] 

RIN 2120–AA64 

Airworthiness Directives; CPAC, Inc. 

Airplanes 

AGENCY: Federal Aviation 

Administration (FAA), DOT. 

ACTION: Final rule. 

SUMMARY: We are superseding an 

existing airworthiness directive (AD) for 

all CPAC, Inc. (type certificate formerly 

held by Commander Aircraft 

Corporation, Gulfstream Aerospace 

Corporation, and Rockwell 

International) Models 112, 112B, 112TC, 

112TCA, 114, 114A, 114B, and 114TC 

airplanes. That AD currently requires a 

one-time inspection of the elevator spar 

for cracks and, if any crack is found, 

either replace with a serviceable 

elevator spar that is found free of cracks 

or repair/modify the elevator spar with 

an FAA-approved method. That AD also 

requires reporting to the FAA the results 

of the inspection. Since we issued that 

AD, using the data collected through the 

reporting requirement, we have 

determined there is a need for 

continued inspections. This new AD 

requires repetitive inspections of the 

elevator spar for cracks and, if any crack 

is found, either replacing with a 

serviceable elevator spar that is free of 

any cracks and/or corrosion or 

repairing/modifying the elevator spar 

with an FAA-approved procedure. We 

are issuing this AD to correct the unsafe 

condition on these products. 

DATES: This AD is effective March 15, 

2012. 

Examining the AD Docket 

You may examine the AD docket on 

the Internet at http:// 

www.regulations.gov; or in person at the 

Docket Management Facility between 

9 a.m. and 5 p.m., Monday through 

Friday, except Federal holidays. The AD 

docket contains this AD, the regulatory 

evaluation, any comments received, and 

other information. The address for the 

Docket Office (phone: (800) 647–5527) 

is Document Management Facility, U.S. 

Department of Transportation, Docket 

Operations, M–30, West Building 

Ground Floor, Room W12–140, 1200 

New Jersey Avenue SE., Washington, 

DC 20590. 

FOR FURTHER INFORMATION CONTACT: T.N. 

Baktha, Senior Aerospace Engineer, 

FAA, Wichita Aircraft Certification 

Office, 1801 Airport Road, Room 100, 

Wichita, Kansas 67209; phone: (316) 

946–4155; fax: (316) 946–4107; email: 

t.n.baktha@faa.gov. 

SUPPLEMENTARY INFORMATION: 

Discussion 

We issued a notice of proposed 

rulemaking (NPRM) to amend 14 CFR 

part 39 to supersede AD 2011–07–13, 

Amendment 39–16650 (76 FR 18376, 

April 4, 2011). That AD applies to the 

specified products. The NPRM 

published in the Federal Register on 

October 17, 2011 (76 FR 64038). That 

NPRM proposed to retain all of the 

requirements of AD 2011–07–13 and 

make the previous one-time inspection 

repetitive. 

Comments 

We gave the public the opportunity to 

participate in developing this AD. The 

following presents the comments 

received on the proposal (76 FR 64038, 

October 17, 2011) and the FAA’s 

response to each comment. 

Request for Clarification 

James D. Richards of Aerodyme 

Corporation requested additional 

information be added to the final rule 

AD action to clarify whether or not the 

inspection intervals and procedures in 

this AD take precedence over those 

specified in the FAA-approved Parts 

Manufacturer Approval (PMA) Elevator 

Spars 44211–RE9 and 44211–RE10, 

Instructions for Continued 

Airworthiness, original issue date May 

5, 2011. 

James D. Richards obtained a PMA for 

CPAC, Inc. Models 112, 112B, 112TC, 

112TCA, 114, 114A, 114B, and 114TC 

airplanes elevator spars. The PMA 

Instructions for Continued 

Airworthiness have inspection intervals 

and procedures that are different from 

the intervals and procedures specified 

in the proposed AD (76 FR 64038, 

October 17, 2011). 

We agree with the commenter. We do 

not want to have two different 

inspection intervals and procedures for 

the same elevator spars. We revised this 

AD as requested and added information 

into paragraph (f) to clarify that the 

actions required in this AD take 

precedence over those contained in 

PMA Elevator Spars 44211–RE9 and 

44211–RE10, Instructions for Continued 

Airworthiness, original issue date May 

5, 2011. 

Request for Additional Information 

Fredrick E. Maupertuis requested that 

specific information be added to 

paragraph (l) Special Flight Permit of 

the final rule AD action about allowable 

crack criteria. Fredrick E. Maupertuis 

questioned whether the number of 

cracks, the length of the cracks, and/or 

the orientation of cracks found during 

an inspection will be a determining 

factor in obtaining a special flight 

permit. 

We agree with the commenter because 

the requested information was not 

included in the proposed AD (76 FR 

64038, October 17, 2011). We revised 

this AD as requested by adding crack 

criteria and allowances into paragraph 

(l). 

Conclusion 

We reviewed the relevant data, 

considered the comments received, and 

determined that air safety and the 

public interest require adopting the AD 

with the changes described previously 

and minor editorial changes. We have 

determined that these minor changes: 

• Are consistent with the intent that 

was proposed in the NPRM (76 FR 

64038, October 17, 2011) for correcting 

the unsafe condition; and 

• Do not add any additional burden 

upon the public than was already 

proposed in the NPRM (76 FR 64038, 

October 17, 2011). 

We also determined that these 

changes will not increase the economic 

burden on any operator or increase the 

scope of the AD. 


emcdonald on DSK29S0YB1PROD with RULES
6664 Federal Register / Vol. 77, No. 27 / Thursday, February 9, 2012 / Rules and Regulations 

Interim Action 

We consider this AD interim action. 

We continue to evaluate the reported 

data and repair procedures to determine 

a possible terminating action. Based on 

this determination, we may initiate 

further rulemaking action if needed to 

address the unsafe condition identified 

in this AD. 

Costs of Compliance 

We estimate that this AD affects 773 

airplanes of U.S. registry. 

We estimate the following costs to 

comply with this AD: 

ESTIMATED COSTS

Action Labor cost Parts cost Cost per 

product 

Cost on U.S. 

operators 

Inspection of the elevator spar ....................... 8 work-hours × $85 per hour = $680 ............. N/A $680 $525,640 

We estimate the following costs to do 

any replacement that will be required 

based on the results of the inspection. 

We have no way of determining the 

number of aircraft that might need this 

replacement: 

ON-CONDITION COSTS

Action Labor cost 

per elevator spar 

Parts cost 

per elevator 

spar 

Cost per 

product per 

elevator spar 

Replace cracked elevator spar with 

a serviceable elevator spar.

Up to 16 work-hours × $85 per 

hour = $1,360.

May range from $100 to $1,000 ... May range from $1,460 to $2,360. 

Replace cracked elevator spar with 

a new elevator spar.

Up to 16 work-hours × $85 per 

hour = $1,360.

$1,250 ........................................... $2,610. 

We estimate the following costs to do 

any repair/modification that will be 

required based on the results of the 

inspection. We have no way of 

determining the number of aircraft that 

might need this repair/modification: 

ON-CONDITION COSTS

Action Labor cost Parts cost Cost per 

airplane 

Repair/modify cracked elevator spar ............................ Up to 26 work-hours × $85 per hour = $2,210 ............ * $1,690 $3,900 

* An STC is available to repair the elevator spars and the STC holder sells the repair kit in pairs only. Kits to repair only one side of the elevator are not available for sale. The parts cost in the table above is for a pair of repair kits. The STC holder currently charges $2,250 to install both 

repair kits. 

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), 

(3) Will not affect intrastate aviation 

in Alaska, and 

(4) 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. 

List of Subjects in 14 CFR Part 39 

Air transportation, Aircraft, Aviation 

safety, Incorporation by reference, 

Safety. 

Adoption of the Amendment 

Accordingly, under the authority 

delegated to me by the Administrator, 

the FAA amends 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 airworthiness directive (AD) 

2011–07–13, Amendment 39–16650 (76 

FR 18376, April 4, 2011), and adding 

the following new AD: 

2012–02–10 CPAC, Inc. (Type Certificate 

Formerly Held by Commander Aircraft 

Corporation, Gulfstream Aerospace 


emcdonald on DSK29S0YB1PROD with RULES
Federal Register / Vol. 77, No. 27 / Thursday, February 9, 2012 / Rules and Regulations 6665 

Corporation, and Rockwell 

International): Amendment 39–16933; 

Docket No. FAA–2011–1128; Directorate 

Identifier 2011–CE–031–AD. 

(a) Effective Date 

This airworthiness directive (AD) is 

effective March 15, 2012. 

(b) Affected ADs 

This AD supersedes AD 2011–07–13, 

Amendment 39–16650 (76 FR 18376, April 4, 

2011). 

(c) Applicability 

This AD applies to CPAC, Inc. (type 

certificate formerly held by Commander 

Aircraft Corporation, Gulfstream Aerospace 

Corporation, and Rockwell International) 

Models 112, 112B, 112TC, 112TCA, 114, 

114A, 114B, and 114TC airplanes, all serial 

numbers, certificated in any category. Type 

Certificate No. A12SO does not include 

Models 112A and 115. The Model 112A is a 

Rockwell ‘‘marketing name’’ for the Model 

112. The Model 115 is a Rockwell ‘‘marketing 

name’’ for the Model 114. Since they are 

type-certificated as Model 112 and Model 

114, this AD is applicable to the Models 

112A and 115. 

(d) Subject 

Joint Aircraft System Component (JASC)/ 

Air Transport Association (ATA) of America 

Code 55, Stabilizers. 

(e) Unsafe Condition 

This AD was prompted by reports of a total 

of nine elevator spar cracks across seven of 

the affected airplanes, including a crack of 

2.35 inches just below the outboard hinge of 

the right-hand elevator. We are issuing this 

AD to prevent structural failure of the 

elevator spar due to such cracking, which 

could result in separation of the elevator 

from the airplane with consequent loss of 

control. 

(f) Compliance 

Comply with this AD within the 

compliance times specified, unless already 

done. The inspection intervals and 

procedures in this AD take precedence over 

those contained in Parts Manufacturer 

Approval (PMA) Elevator Spars 44211–RE9 

and 44211–RE10, Instructions for Continued 

Airworthiness, original issue date May 5, 

2011. 

(g) Inspection Requirement Retained From 

AD 2011–07–13, Amendment 39–16650 (76 

FR 18376, April 4, 2011) 

Within the next 5 hours time-in-service 

(TIS) after April 4, 2011 (the effective date 

retained from AD 2011–07–13 (76 FR 18376, 

April 4, 2011)), visually inspect the left-hand 

(LH) and right-hand (RH) elevator spar 

behind and around the outboard hinge 

bracket on the elevator spar for cracks. Do the 

inspection following the procedures 

specified in paragraph (j) of this AD. If cracks 

are found during this inspection, take the 

necessary corrective actions specified in 

paragraph (k) of this AD. 

(h) Reporting Requirement Retained From 

AD 2011–07–13, Amendment 39–16650 (76 

FR 18376, April 4, 2011) 

Within 30 days after the inspection 

required in paragraph (g) of this AD, report 

the results of the inspection to the FAA, 

Wichita Aircraft Certification Office (ACO), 

Attn: T.N. Baktha, Senior Aerospace 

Engineer, 1801 Airport Road, Room 100; 

Wichita, Kansas 67209; phone: (316) 946– 

4155; fax: (316) 946–4107; email: 

t.n.baktha@faa.gov. Include the following 

information: 

(1) Airplane model and serial number. 

(2) Hours TIS at time of inspection. 

(3) Annotate any cracking found, including 

the exact location and length of any cracks. 

(4) Any installations, repairs, 

modifications, etc. that have been done on 

your airplane in the elevator spar area or that 

could have affected the elevator spar. 

(5) Type of operation primarily flown. 

(i) Repetitive Inspection Requirement 

As a result of the inspection required in 

paragraph (g) of this AD, if the elevator spar 

was: 

(1) Replaced with a new elevator spar, 

within the next 300 hours TIS after the 

replacement, visually inspect the elevator 

spar behind the outboard hinge bracket and 

surrounding area for cracks. Repetitively 

inspect thereafter at intervals not to exceed 

12 months or 150 hours TIS, whichever 

occurs first. Do the inspection following the 

procedures specified in paragraph (j) of this 

AD. 

(2) Replaced with a serviceable elevator 

spar (one that was in service before and had 

no cracks and/or corrosion), within the next 

150 hours TIS after the replacement, visually 

inspect the elevator spar behind the outboard 

hinge bracket and surrounding area for 

cracks. Repetitively inspect thereafter at 

intervals not to exceed 12 months or 150 

hours TIS, whichever occurs first. Do the 

inspection following the procedures 

specified in paragraph (j) of this AD. 

(3) Found free of cracks, within the next 

150 hours TIS after the inspection, visually 

inspect the elevator spar behind the outboard 

hinge bracket and surrounding area for 

cracks. Repetitively inspect thereafter at 

intervals not to exceed 12 months or 150 

hours TIS, whichever occurs first. Do the 

inspection following the procedures 

specified in paragraph (j) of this AD. 

(j) Inspection Procedures 

(1) Disconnect the elevator trim pushrod at 

the trim tab. 

(2) Remove the hinge bolts at the 

horizontal stabilizer points. 

(3) Remove six screws and two bolts at the 

inboard end of the elevator and remove the 

elevator. 

(4) Remove all fasteners common to the 

elevator outboard aft end rib, part number (P/ 

N) 44330, and elevator skin, P/N 44323. 

(5) Remove the remaining two fasteners 

common to the elevator outboard aft end rib 

(P/N 44330) and the elevator spar, P/N 

44211. 

(6) Remove the elevator aft end rib, P/N 

44330, to gain access to the aft side of the 

elevator spar. 

(7) Remove the four bolts, washers, and 

nuts that secure the outboard elevator hinge 

bracket, P/N 44285. 

(8) Remove elevator hinge bracket, P/N 

44285, from the elevator spar. 

(9) Clean in and around the location of the 

elevator outboard hinge bracket, outboard 

elevator hinge, and the outboard elevator 

hinge bracket (as applicable) on the elevator 

spar and visually inspect for cracks. Use a 

10× magnifier to facilitate the detection of 

any crack. 

(k) Corrective Actions 

(1) If cracks are found during any 

inspection required in paragraphs (g), (i)(1), 

(i)(2), or (i)(3) of this AD, before further flight, 

either replace the elevator spar with a new 

spar or a serviceable spar that is found free 

of cracks and/or corrosion or repair/modify 

the elevator spar following a procedure 

approved for this AD by the FAA, Wichita 

ACO; 

(2) After doing the actions required in 

paragraph (k)(1) of this AD, before further 

flight, reassemble the elevator assembly, 

rebalance the elevator, and reinstall on the 

airplane following standard repair practices. 

Ensure elevator rigging is within tolerance, 

and that the system operates with ease, 

smoothness, and positiveness appropriate to 

its function; and 

(3) After taking corrective action, continue 

with the repetitive inspections required in 

paragraphs (i)(1), (i)(2), and (i)(3) of this AD. 

(l) Special Flight Permit 

(1) Special flight permits are permitted for 

daytime visual flight rules (VFR) only, 

restricted to crew, calm weather, reduced 

speed not to exceed 111 knots calibrated air 

speed (KCAS), and not to exceed 5 flight 

hours when cracks are found in the elevator 

spar if: 

(i) The cracks are at or near the outboard 

hinge bracket; 

(ii) The cracks are 1.25 inches long or less; 

and 

(iii) There is no more than one crack on the 

top and one at the bottom of the hinge 

bracket. 

(2) Special flight permits are not allowed 

if: 

(i) The crack length is greater than 1.25 

inches; or 

(ii) The number of cracks is more than two. 

(m) Paperwork Reduction Act Burden 

Statement 

A federal agency may not conduct or 

sponsor, and a person is not required to 

respond to, nor shall a person be subject to 

a penalty for failure to comply with a 

collection of information subject to the 

requirements of the Paperwork Reduction 

Act unless that collection of information 

displays a current valid OMB Control 

Number. The OMB Control Number for this 

information collection is 2120–0056. Public 

reporting for this collection of information is 

estimated to be approximately 5 minutes per 

response, including the time for reviewing 

instructions, completing and reviewing the 

collection of information. All responses to 

this collection of information are mandatory. 

Comments concerning the accuracy of this 

burden and suggestions for reducing the 


emcdonald on DSK29S0YB1PROD with RULES
6666 Federal Register / Vol. 77, No. 27 / Thursday, February 9, 2012 / Rules and Regulations 

burden should be directed to the FAA at: 800 

Independence Ave. SW., Washington, DC 

20591, Attn: Information Collection 

Clearance Officer, AES–200. 

(n) AMOCs 

(1) The Manager, Wichita ACO, FAA, has 

the authority to approve AMOCs for this AD, 

if requested using the procedures found in 14 

CFR 39.19. In accordance with 14 CFR 39.19, 

send your request to your principal inspector 

or local Flight Standards District Office, as 

appropriate. If sending information directly 

to the manager of the ACO, send it to the 

attention of the person identified in the 

Related Information section of this AD. 

(2) Before using any approved AMOC, 

notify your appropriate principal inspector, 

or lacking a principal inspector, the manager 

of the local flight standards district office/ 

certificate holding district office. 

(3) AMOCs approved for AD 2011–07–13, 

Amendment 39–16650 (76 FR 18376, April 4, 

2011), are approved for this AD. 

(o) Related Information 

For more information about this AD, 

contact T.N. Baktha, Senior Aerospace 

Engineer, Wichita ACO, FAA, 1801 Airport 

Road, Room 100, Wichita, Kansas 67209; 

phone: (316) 946–4155; fax: (316) 946–4107; 

email: t.n.baktha@faa.gov. 

Issued in Kansas City, Missouri, on January 

25, 2012. 

John Colomy, 

Acting Manager, Small Airplane Directorate, 

Aircraft Certification Service. 

[FR Doc. 2012–1998 Filed 2–8–12; 8:45 am] 

BILLING CODE 4910–13–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 39 

[Docket No. FAA–2011–0946; Directorate 

Identifier 2011–NE–02–AD; Amendment 39– 

16926; AD 2012–02–03] 

RIN 2120–AA64 

Airworthiness Directives; CFM 

International, S.A. Turbofan Engines 

AGENCY: Federal Aviation 

Administration (FAA), DOT. 

ACTION: Final rule. 

SUMMARY: We are adopting a new 

airworthiness directive (AD) for certain 

CFM International, S.A. model CFM56– 

5B series turbofan engines. This AD was 

prompted by a normal quality sampling 

at CFM International, S.A. that isolated 

a production batch of fan blades with 

nonconforming geometry of mid-span 

shroud tips of the fan blades. This AD 

requires removing from service certain 

serial number (S/N) fan blades. We are 

issuing this AD to prevent an inflight 

shutdown (IFSD) of one or more engines 

following foreign object damage (FOD) 

or a bird strike. 

DATES: This AD is effective March 15, 

2012. 

The Director of the Federal Register 

approved the incorporation by reference 

of a certain publication listed in the AD 

as of March 15, 2012. 

ADDRESSES: For service information 

identified in this AD, contact CFM 

International, Inc., Aviation Operations 

Center, 1 Neumann Way, M/D Room 

285, Cincinnati, OH 45125; 

International Phone: 1–(513) 552–3272; 

USA Phone: (877) 432–3272; 

International Fax: 1–(513) 552–3329; 

USA Fax: (877) 432–3329; email: 

geae.aoc@ge.com; or CFM International 

S.A., Customer Support Center, 

International Phone: 33 1 64 14 88 66; 

Fax: 33 1 64 79 85 55; email: 

snecma.csc@snecma.fr. You may review 

copies of the referenced service 

information at the FAA, Engine & 

Propeller Directorate, 12 New England 

Executive Park, Burlington, MA. For 

information on the availability of this 

material at the FAA, call (781) 238– 

7125. 

Examining the AD Docket 

You may examine the AD docket on 

the Internet at http:// 

www.regulations.gov; or in person at the 

Docket Management Facility between 

9 a.m. and 5 p.m., Monday through 

Friday, except Federal holidays. The AD 

docket contains this AD, the regulatory 

evaluation, any comments received, and 

other information. The address for the 

Docket Office (phone: (800) 647–5527) 

is Document Management Facility, U.S. 

Department of Transportation, Docket 

Operations, M–30, West Building 

Ground Floor, Room W12–140, 1200 

New Jersey Avenue SE., Washington, 

DC 20590. 

FOR FURTHER INFORMATION CONTACT: 

Martin Adler, Aerospace Engineer, 

Engine Certification Office, FAA, Engine 

& Propeller Directorate, 12 New England 

Executive Park, Burlington, MA 01803; 

phone: (781) 238–7157; fax: (781) 238– 

7199; email: martin.adler@faa.gov. 

SUPPLEMENTARY INFORMATION: 

Discussion 

We issued a notice of proposed 

rulemaking (NPRM) to amend 14 CFR 

part 39 to include an AD that would 

apply to the specified products. That 

NPRM published in the Federal 

Register on October 18, 2011 (76 FR 

64293). That NPRM proposed to require 

removing from service within 5,000 

flight hours (FHs) after the effective date 

of the AD, any fan blade, P/N 338–002– 

114–0, that has an S/N listed in CFM 

International Service Bulletin (SB) No. 

CFM56–5B S/B 72–0777, Revision 1, 

dated April 11, 2011. After the effective 

date of the AD, it would also prohibit 

installing any fan blade, P/N 338–002– 

114–0, that has an S/N listed in 

Appendix A of CFM International SB 

No. CFM56–5B S/B 72–0777, Revision 

1, dated April 11, 2011. 

Comments 

We gave the public the opportunity to 

participate in developing this AD. The 

following presents the comments 

received on the proposal and the FAA’s 

response to each comment. 

Request to Reword the Unsafe 

Condition Statement 

One commenter, CFM International, 

S.A., requested that we reword the 

unsafe condition statement ‘‘This defect 

would cause the upper panel of the fan 

blade to be liberated following FOD or 

a bird strike and likely result in an inflight shutdown (IFSD)’’ to ‘‘This nonconforming condition could increase the 

potential for damage during a foreign 

object impact. This secondary damage 

could include liberation of the upper 

panel of the blade, which increases the 

potential for in-flight shutdown.’’ The 

commenter stated that the outcome of 

FOD or bird strike event will not 

necessarily result in an outer panel 

release, therefore it is suggested that the 

sentence be replaced to more accurately 

reflect the possible outcome. 

We agree. The unsafe condition 

increases the likelihood of separation 

after an event, but will not result in 

separation in every case. We changed 

paragraph (d) of the AD, which is the 

only place in the final rule that this 

information appears, to state that this 

defect could cause the upper panel of 

the fan blade to be liberated following 

FOD or a bird strike and likely result in 

an IFSD. 

Request for Terminating Action 

One commenter, American Airlines, 

requested that we establish a 

terminating action that would specify a 

point at which the AD would be 

considered closed. This would allow the 

airline to limit the time that it must 

verify compliance with the AD and 

reduce operating costs. 

We do not agree. The AD as written 

clearly limits the fan blade serial 

numbers affected. The affected blades 

must never be installed in operating 

engines. We have no mechanism to 

assure that the affected fan blades have 

been completely purged from all 

inventories and so we can not stipulate 

when the AD is no longer applicable. 

We did not change the AD. 


emcdonald on DSK29S0YB1PROD with RULES