Airworthiness Directives; McDonnell Douglas Model DC-9 and Model DC-9-80 Series Airplanes, Model MD-88 Airplanes, and C-9 (Military) Airplanes

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 93-NM-115-AD; Amendment 39-8875; AD 94-08-04]

Airworthiness Directives; McDonnell Douglas Model DC-9 and Model

DC-9-80 Series Airplanes, Model MD-88 Airplanes, and C-9 (Military)

Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment supersedes an existing airworthiness directive

(AD), applicable to certain McDonnell Douglas Model DC-9 and Model DC-

9-80 series airplanes, and C-9 (military) airplanes, that currently

requires inspections to detect cracking in the skin and doublers around

the upper anticollision light cutout, and repair, if necessary. This

amendment expands the applicability to include additional Model DC-9-80

series airplanes and Model MD-88 airplanes, and requires the

performance of stress coining procedures on the plate nut clearance

holes or installation of shims and an external doubler. This amendment

is prompted by a report that stress coining procedures were not

performed on the plate nut clearance holes of the upper anticollision

light doublers during production of certain airplanes. The actions

specified by this AD are intended to prevent crack growth in the

doublers, which could result in damage to the adjacent structure, and

subsequent loss of cabin structural integrity.

DATES: Effective May 23, 1994.

The incorporation by reference of certain publications listed in

the regulations is approved by the Director of the Federal Register as

of May 23, 1994.

ADDRESSES: The service information referenced in this AD may be

obtained from McDonnell Douglas Corporation, P.O. Box 1771, Long Beach,

California 90801-1771, Attention: Business Unit Manager, Technical

Administrative Support, Department L51, M.C. 2-98. This information may

be examined at the Federal Aviation Administration (FAA), Transport

Airplane Directorate, Rules Docket, 1601 Lind Avenue, SW., Renton,

Washington; or at the FAA, Transport Airplane Directorate, Los Angeles

Aircraft Certification Office, 3229 East Spring Street, Long Beach,

California; or at the Office of the Federal Register, 800 North Capitol

Street NW., suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT: David Hempe, Aerospace Engineer,

Airframe Branch, ANM-122L, FAA, Transport Airplane Directorate, Los

Angeles Aircraft Certification Office, 3229 East Spring Street, Long

Beach, California 90806-2425; telephone (310) 988-5224; fax (310) 988-

5210.

SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal

Aviation Regulations by superseding all or portions of two existing

AD's was published in the Federal Register on October 7, 1993 (58 FR

52240).

That action proposed to supersede AD 85-19-03 R2, Amendment 39-5844

(53 FR 3738, February 9, 1988), which is applicable to Model DC-9 and

Model DC-9-80 series airplanes, and C-9 (military) airplanes, having

fuselage numbers 1 through 1371. That AD requires repetitive

inspections, at intervals of 3,500 landings, to detect cracking in the

skin and doublers around the upper anticollision light cutout, and

repair, if necessary. That AD also provides for the performance of

stress coining procedures on the plate nut clearance holes in the upper

anticollision light cutout as optional terminating action for the

repetitive inspection requirement. The notice proposed to supersede

this AD to expand its applicability to include affected airplanes

through fuselage number 2042, and to increase the repetitive inspection

interval to 4,500 landings.

The notice also proposed to supersede portions of AD 90-18-03,

Amendment 39-6701 (55 FR 34704, August 24, 1990), which is applicable

to Model DC-9 and DC-9-80 series airplanes, Model MD-88 airplanes, and

C-9 (military) airplanes. Among other things, that AD currently

requires repetitive inspections and eventual modification of the plate

nut clearance holes in the upper doublers. The notice proposed to

expand the applicability of those requirements to include additional

affected airplanes.

Interested persons have been afforded an opportunity to participate

in the making of this amendment. Due consideration has been given to

the comments received.

Several commenters support the proposed rule.

One commenter notes that, in the Discussion section of the

proposal, the description of the applicability of AD 90-18-03 was

confusing. The commenter suggests that a more succinct way of stating

applicability for the existing AD would be to state that the

requirements of AD 90-18-03 are applicable to ``all Model DC-9-10, -20,

-30, -40, and -50 series airplanes and C-9 airplanes, and to Model DC-

9-80 series airplanes and MD-88 airplanes, fuselage numbers 1 through

1371.'' The proposal stated that AD 90-18-03 is applicable to ``all

Model DC-9-10, -20, -30, -40, and -50 series airplanes and C-9

airplanes, but only to certain Model DC-9-80 series airplanes and MD-88

airplanes, namely, those having fuselage numbers 1248 through 1371.''

The FAA finds that either way of describing applicability for the

requirements of AD 90-18-03 adequately summarizes the applicability of

the existing AD.

This same commenter indicates that there was an error in the

description of the service bulletin in the Discussion section of the

proposal. The commenter notes that the description of the service

bulletin, which is referenced in the proposal as the appropriate source

of service information, omitted Model DC-9-80 series airplanes. The FAA

concurs that an error was made in the Discussion section of the

proposal. However, the entire remainder of the AD, including the

applicability of the rule, as well as paragraphs (b) and (c) of the

rule, clearly states that the rule is applicable to Model DC-9-80

series airplanes. Therefore, no change to the final rule is necessary.

This commenter further requests that the number of airplanes

presented in the cost estimate in the preamble to the notice be

verified. The commenter notes that, since the applicability of the

proposal is for airplanes having fuselage numbers 1 through 2042, the

estimated number of airplanes affected by the proposal could not

possibly be 1,500 airplanes, as stated in the proposal. The FAA concurs

that the number of affected airplanes was inaccurately estimated. The

economic impact information, below, has been revised to reflect this

increase in the number of affected airplanes.

Further, this commenter notes that the fuselage number referenced

in the Discussion section of the proposal contained a typographical

error. The FAA concurs. The FAA acknowledges this typographical error

and corrects it by stating that the stress coining procedure on the

plate nut clearance holes in the upper anticollision light doublers has

not been accomplished during production of Model DC-9-80 series

airplanes and Model MD-88 airplanes having fuselage numbers 1372

through 2042. The fuselage numbers were repeatedly referenced correctly

in numerous other parts of the AD, including paragraph (c). Therefore,

the FAA finds that revision to the final rule is unnecessary.

This same commenter requests that paragraphs (a), (b), and (c) of

the proposal be revised to correctly reference the McDonnell Douglas

DC-9 Service Sketch. The FAA concurs that references to the sketch

number contained a typographical error. Therefore, paragraphs (a), (b),

and (c) of the final rule have been revised to correctly reference the

sketch as McDonnell Douglas DC-9 Service Sketch 3626E.

Two commenters request that the proposal be revised to include a

second alternative that would terminate the requirement for the

repetitive inspections, as specified in the referenced service

bulletin, McDonnell Douglas DC-9 Service Bulletin 53-186, Revision 6,

dated May 13, 1993. The commenters state that the service bulletin

provides two terminating actions: one, to stress coin the holes in the

doubler (as stated in the proposal), or two, to install shims and an

external doubler on the anticollision light cutout. The FAA concurs.

The FAA has reviewed the procedures described in the service bulletin

to install shims and an external doubler and has determined that this

installation would preclude cracking in the skin and doublers around

the upper anticollision light cutout on the fuselage. Therefore,

paragraphs (a), (b), and (c) of the final rule have been revised to

include the option of installing shims and an external doubler on the

anticollision light cutout, which would terminate the requirement for

the repetitive inspections required by these paragraphs.

After careful review of the available data, including the comments

noted above, the FAA has determined that air safety and the public

interest require the adoption of the rule with the changes previously

described. The FAA has determined that these changes will neither

increase the economic burden on any operator nor increase the scope of

the AD.

There are approximately 2,042 McDonnell Douglas Model DC-9 and

Model DC-9-80 series airplanes, Model MD-88 airplanes, and C-9

(military) airplanes of the affected design in the worldwide fleet. Of

this number, approximately 1,022 are of U.S. registry. The FAA

estimates that 440 airplanes of U.S. registry are currently affected by

AD 85-19-03 R2 and AD 90-18-03, while approximately 582 additional

U.S.-registered airplanes will be affected by the requirements of this

AD.

The costs associated with the inspection requirements will take

approximately 10 work hours per airplane per inspection, at an average

labor rate of $55 per airplane per inspection cycle. Based on these

figures, the total cost impact of these inspection requirements on U.S.

operators is estimated to be $550 per airplane per inspection cycle.

For operators currently affected by AD 85-19-03 R2 and AD 90-18-03,

there will be no new costs associated with these inspection

requirements. For some of these operators, the economic burden will

actually be lessened since the interval for repetitive inspection will

be increased from the previous 3,500 landings to 4,500 landings in this

AD. For the 582 newly affected airplanes of U.S. registry, the total

cost impact of the inspection requirements will be $320,100 per

inspection cycle.

The costs associated with the stress coining procedure that is

required by this AD entail approximately 4.6 work hours per airplane,

at an average labor rate of $55 per work hour. The costs of required

parts is expected to be negligible. Based on these figures, the total

cost impact of the stress coining procedure requirements on U.S.

operators is estimated to be $258,566, or $253 per airplane. Of this

total amount, $147,246 represents the additional costs applicable to

the 582 newly affected airplanes of U.S. registry.

The total cost impact figures discussed above are based on

assumptions that no operator has yet accomplished any of the

requirements of this AD action, and that no operator would accomplish

those actions in the future if this AD were not adopted.

Additionally, the number of required work hours discussed above is

presented as if the accomplishment of the actions in this AD were to be

conducted as ``stand alone'' actions. However, in actual practice,

these actions for the most part will be accomplished coincidentally or

in combination with normally scheduled airplane inspections and other

maintenance program tasks. Therefore, the actual number of necessary

additional work hours will be minimal in many instances, as will the

costs associated with special airplane scheduling.

The regulations adopted herein will not have substantial direct

effects 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, in

accordance with Executive Order 12612, it is determined that this final

rule does not have sufficient federalism implications to warrant the

preparation of a Federalism Assessment.

For the reasons discussed above, I certify that this action (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. A final evaluation has been prepared for this action

and it is contained in the Rules Docket. A copy of it may be obtained

from the Rules Docket at the location provided under the caption

ADDRESSES.

List of Subjects in 14 CFR Part 39

Air transportation, Aircraft, Aviation safety, Incorporation by

reference, Safety.

Adoption of the Amendment

Accordingly, pursuant to the authority delegated to me by the

Administrator, the Federal Aviation Administration amends 14 CFR part

39 of the Federal Aviation Regulations as follows:

PART 39--AIRWORTHINESS DIRECTIVES

1. The authority citation for part 39 continues to read as follows:

Authority: 49 U.S.C. App. 1354(a), 1421 and 1423; 49 U.S.C.

106(g); and 14 CFR 11.89.

Sec. 39.13 [Amended]

2. Section 39.13 is amended by removing amendment 39-5844 (53 FR

3738, February 9, 1988), and by adding a new airworthiness directive

(AD), amendment 39-8875, to read as follows:

94-08-04 McDonnell Douglas: Amendment 39-8875. Docket 93-NM-115-AD.

Supersedes AD 85-19-03 R2, Amendment 39-5844.

Applicability: All Model DC-9-10, -20, -30, -40, and -50 series

airplanes and C-9 (military) airplanes; and Model DC-9-81 (MD-81),

DC-9-82 (MD-82), DC-9-83 (MD-83), and DC-9-87 (MD-87) series

airplanes and Model MD-88 airplanes, having fuselage numbers 909

through 2042, inclusive; certificated in any category.

Compliance: Required as indicated, unless accomplished

previously.

Note 1: Inspections, repairs, or modifications (stress coining

or installation of shims and an external doubler) accomplished prior

to the effective date of this amendment in accordance with McDonnell

Douglas DC-9 Service Bulletin 53-186, original issue through

Revision 6; or McDonnell Douglas DC-9 Service Bulletin 53-216,

original issue through Revision 3; are considered acceptable for

compliance with the applicable action specified in this amendment.

To prevent crack growth in the doubler, which could result in

damage to the adjacent structure, accomplish the following:

(a) For all Model DC-9-10, -20, -30, -40, and -50 series

airplanes, and C-9 (military) airplanes: Prior to the accumulation

of 30,000 total landings or within 4,500 landings after the

effective date of this AD, whichever occurs later, perform an eddy

current inspection to detect cracking in the skin and doublers

around the upper anticollision light cutout on the fuselage, in

accordance with McDonnell Douglas DC-9 Service Bulletin 53-186,

Revision 6, dated May 13, 1993.

(1) If no cracking is detected, accomplish the requirements of

paragraphs (a)(1)(i) and (a)(1)(ii) of this AD.

(i) Repeat that inspection thereafter at intervals not to exceed

4,500 landings until either one of the procedures required by

paragraph (a)(1)(ii) of this AD is accomplished; and

(ii) Prior to the accumulation of 100,000 total landings or

within 4 years after September 24, 1990 (the effective date of AD

90-18-03, Amendment 39-6701), whichever occurs later, either stress

coin the plate nut clearance holes, or install shims and an external

doubler; in accordance with Condition I, Phase 2, of the

accomplishment instructions of McDonnell Douglas DC-9 Service

Bulletin 53-186, Revision 6, dated May 13, 1993. Accomplishment of

either the stress coining procedure, or installing shims and an

external doubler, constitutes terminating action for the repetitive

inspection requirement of paragraph (a) of this AD.

(2) If any cracking is detected as a result of any inspection

required by this paragraph, prior to further flight, accomplish the

requirements of paragraph (a)(2)(i) or (a)(2)(ii) of this AD, as

applicable.

(i) For cracks specified as Condition II and Condition III in

McDonnell Douglas DC-9 Service Bulletin 53-186, Revision 6, dated

May 13, 1993: Repair in accordance with McDonnell Douglas DC-9

Service Bulletin 53-186, Revision 6, dated May 13, 1993; McDonnell

Douglas SB 09530186; or McDonnell Douglas DC-9 Service Sketch 3626E.

Accomplishment of any one of these repair procedures constitutes

terminating action for the requirements of this AD.

(ii) For cracks specified as Condition IV in McDonnell Douglas

DC-9 Service Bulletin 53-186, Revision 6, dated May 13, 1993: Repair

in accordance with a method approved by the Manager, Los Angeles

Aircraft Certification Office (ACO), FAA, Transport Airplane

Directorate.

(b) For Model DC-9-81, DC-9-82, and DC-9-83 series airplanes

having fuselage numbers 909 through 1247 inclusive: Prior to the

accumulation of 30,000 total landings or within 4,500 landings after

the effective date of this AD, whichever occurs later, perform an

eddy current inspection to detect cracking in the skin and doublers

around the upper anticollision light cutout on the fuselage, in

accordance with McDonnell Douglas DC-9 Service Bulletin 53-186,

Revision 6, dated May 13, 1993.

Note 2: Although fuselage numbers 909 through 1247 include Model

DC-9-30 and -50 series airplanes, those airplanes are addressed in

paragraph (a) of this AD, and as such, operators of those airplanes

must accomplish the requirements of paragraph (a) of this AD.

(1) If no cracking is detected, accomplish the requirements of

paragraphs (b)(1)(i) and (b)(1)(ii) of this AD.

(i) Repeat that inspection thereafter at intervals not to exceed

4,500 landings until either one of the procedures required by

paragraph (b)(1)(ii) of this AD is accomplished; and

(ii) Prior to the accumulation of 75,000 total landings or

within 4 years after September 24, 1990 (the effective date of AD

90-18-03, Amendment 39-6701), whichever occurs later, either stress

coin the plate nut clearance holes, or install shims and an external

doubler, in accordance with Condition I, Phase 2, of the

accomplishment instructions of McDonnell Douglas DC-9 Service

Bulletin 53-186, Revision 6, dated May 13, 1993. Accomplishment of

either the stress coining procedure, or installing shims and an

external doubler, constitutes terminating action for the repetitive

inspection requirements of paragraph (b) of this AD.

(2) If any cracking is detected as a result of any inspection

required by this paragraph, prior to further flight, accomplish the

requirements of paragraph (b)(2)(i) or (b)(2)(ii) of this AD, as

applicable.

(i) For cracks specified as Condition II and Condition III in

McDonnell Douglas DC-9 Service Bulletin 53-186, Revision 6, dated

May 13, 1993: Repair in accordance with McDonnell Douglas DC-9

Service Bulletin 53-186, Revision 6, dated May 13, 1993; McDonnell

Douglas SB 09530186; or McDonnell Douglas DC-9 Service Sketch 3626E.

Accomplishment of any one of these repair procedures constitutes

terminating action for the requirements of this AD.

(ii) For cracks specified as Condition IV in McDonnell Douglas

DC-9 Service Bulletin 53-186, Revision 6, dated May 13, 1993: Repair

in accordance with a method approved by the Manager, Los Angeles

ACO, FAA, Transport Airplane Directorate.

(c) For Model DC-9-81, DC-9-82, DC-9-83, and DC-9-87 series

airplanes, and Model MD-88 airplanes, having fuselage numbers 1248

through 2042 inclusive: Prior to the accumulation of 30,000 total

landings or within 4,500 landings after the effective date of this

AD, whichever occurs later, perform an eddy current inspection to

detect cracking in the skin and doublers around the upper

anticollision light cutout on the fuselage, in accordance with

McDonnell Douglas MD-80 Service Bulletin 53-216, Revision 3, dated

April 23, 1993.

(1) If no cracking is detected, accomplish the requirements of

paragraphs (c)(1)(i) and (c)(1)(ii) of this AD.

(i) Repeat that inspection thereafter at intervals not to exceed

4,500 landings until either one of the procedures required by

paragraph (c)(1)(ii) of this AD is accomplished; and

(ii) Prior to the accumulation of 75,000 total landings or

within 4 years after September 24, 1990 (the effective date of AD

90-18-03, Amendment 39-6701), whichever occurs later, either stress

coin the plate nut clearance holes in accordance with Condition I,

Phase 2, of McDonnell Douglas MD-80 Service Bulletin 53-216,

Revision 3, dated April 23, 1993; or install shims and an external

doubler, in accordance with the accomplishment instructions of that

service bulletin. Accomplishment of either the stress coining

procedure, or installing shims and an external doubler, constitutes

terminating action for the repetitive inspection requirement of

paragraph (c) of this AD.

(2) If any cracking is detected as a result of any inspection

required by this paragraph, prior to further flight, accomplish the

requirements of paragraph (c)(2)(i) or (c)(2)(ii) of this AD, as

applicable.

(i) For cracks specified as Condition II and Condition III in

McDonnell Douglas DC-9 Service Bulletin 53-216, Revision 3, dated

April 23, 1993: Repair in accordance with McDonnell Douglas DC-9

Service Bulletin 53-216, Revision 3, dated April 23, 1993; McDonnell

Douglas SB 09530186; or McDonnell Douglas DC-9 Service Sketch 3626E.

Accomplishment of any one of these repair procedures constitutes

terminating action for the requirements of this AD.

(ii) For cracks specified as Condition IV in McDonnell Douglas

DC-9 Service Bulletin 53-216, Revision 3, dated April 23, 1993:

Repair in accordance with a method approved by the Manager, Los

Angeles ACO, FAA, Transport Airplane Directorate.

(d) This AD supersedes that portion of AD 90-18-03, Amendment

39-6701, which requires inspection and modification in accordance

with the following McDonnell Douglas service bulletins:

DC-9 Service Bulletin 53-186

MD-80 Service Bulletin 53-216

(e) 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, Los Angeles ACO, 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, Los Angeles ACO.

Note 3: Information concerning the existence of approved

alternative methods of compliance with this AD, if any, may be

obtained from the Los Angeles ACO.

(f) Special flight permits may be issued in accordance with

Federal Aviation Regulations (FAR) 21.197 and 21.199 to operate the

airplane to a location where the requirements of this AD can be

accomplished.

(g) The actions shall be done in accordance with McDonnell

Douglas DC-9 Service Bulletin 53-186, Revision 6, dated May 13, 1993

(for Model DC-9 series airplanes), or McDonnell Douglas MD-80

Service Bulletin 53-216, Revision 3, dated April 23, 1993 (for Model

DC-9-80 series airplanes), as applicable. This incorporation by

reference was approved by the Director of the Federal Register in

accordance with 5 U.S.C. 552(a) and 1 CFR Part 51. Copies may be

obtained from McDonnell Douglas Corporation, P.O. Box 1771, Long

Beach, California 90801-1771, Attention: Business Unit Manager,

Technical Administrative Support, Department L51, M.C. 2-98. Copies

may be inspected at the FAA, Transport Airplane Directorate, 1601

Lind Avenue, SW., Renton, Washington; or at the FAA, Transport

Airplane Directorate, Los Angeles Aircraft Certification Office,

3229 East Spring Street, Long Beach, California; or at the Office of

the Federal Register, 800 North Capitol Street, NW., suite 700,

Washington, DC.

(h) This amendment becomes effective on May 23, 1994.

Issued in Renton, Washington, on April 1, 1994.

S. R. Miller,

Acting Manager, Transport Airplane Directorate, Aircraft Certification

Service.

[FR Doc. 94-8325 Filed 4-20-94; 8:45 am]

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