[Federal Register: March 3, 1998 (Volume 63, Number 41)]

[Rules and Regulations]

[Page 10297-10299]

From the Federal Register Online via GPO Access [wais.access.gpo.gov]

[DOCID:fr03mr98-4]



[[Page 10297]]



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DEPARTMENT OF TRANSPORTATION



Federal Aviation Administration



14 CFR Part 39



[Docket No. 97-CE-37-AD; Amendment 39-10365; AD 98-05-04]

RIN 2120-AA64





Airworthiness Directives; American Champion Aircraft Corp. Model

8GCBC Airplanes



AGENCY: Federal Aviation Administration, DOT.



ACTION: Final rule.



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SUMMARY: This amendment supersedes Airworthiness Directive (AD) 87-18-

09, which currently requires inspecting (one-time) the sides of the

front and rear wood spars for compression cracks on certain American

Champion Aircraft Corp. (ACAC) Model 8GCBC airplanes, and repairing or

replacing any wood spar with compression cracks. This AD requires

repetitively inspecting the front and rear wood spars for damage,

including installing any necessary inspection holes; and repairing or

replacing any damaged wood spar. Damage is defined as cracks;

compression cracks; longitudinal cracks through the bolt holes or nail

holes; or loose or missing nails. This AD results from in-flight wing

structural failure on one of the affected airplanes that was in

compliance with the one-time inspection requirement of AD 87-18-09,

plus 4 other ACAC Model 8GCBC accidents and 11 service difficulty

reports (SDR's) of compression cracked spars. The actions specified by

this AD are intended to detect compression cracks and other damage in

the wood spar wing, which, if not corrected, could eventually result in

in-flight structural failure of the wing with consequent loss of the

airplane.



DATES: Effective April 17, 1998.

    The incorporation by reference of certain publications listed in

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

of April 17, 1998.



ADDRESSES: Service information that applies to this AD may be obtained

from the American Champion Aircraft Corp., P.O. Box 37, 32032

Washington Avenue, Highway D, Rochester, Wisconsin 53167. This

information may also be examined at the Federal Aviation Administration

(FAA), Central Region, Office of the Regional Counsel, Attention: Rules

Docket No. 97-CE-37-AD, Room 1558, 601 E. 12th Street, Kansas City,

Missouri 64106; or at the Office of the Federal Register, 800 North

Capitol Street, NW, suite 700, Washington, DC.



FOR FURTHER INFORMATION CONTACT: Mr. William Rohder, Aerospace

Engineer, FAA, Chicago Aircraft Certification Office, 2300 E. Devon

Avenue, Des Plaines, Illinois 60018; telephone: (847) 294-7697;

facsimile: (847) 294-7834.



SUPPLEMENTARY INFORMATION:



Events Leading to the Issuance of This AD



    A proposal to amend part 39 of the Federal Aviation Regulations (14

CFR part 39) to include an AD that would apply to ACAC Model 8GCBC

airplanes was published in the Federal Register as a notice of proposed

rulemaking (NPRM) on September 26, 1997 (62 FR 50527). The NPRM

proposed to:

    --Supersede AD 87-18-09, Amendment 39-5725, which currently

requires inspecting (one-time) the sides of the front and rear wood

spars for compression cracks, repairing or replacing any wood spar with

compression cracks, and re-inspecting immediately after any incident

involving wing damage; and

    --Require installing inspection holes on the top and bottom wing

surfaces, repetitively inspecting the front and rear wood spars for

damage, repairing or replacing any damaged wood spar, and installing

surface covers.

    Accomplishment of the proposed actions as specified in the NPRM

would be as follows:

    --Installations: in accordance with ACAC Service Letter 417, dated

August 14, 1997;

    --Inspections: in accordance with ACAC Service Letter 406, dated

March 28, 1994; and

    --Spar Repair and Replacement, as applicable: in accordance with

Advisory Circular (AC) 43-13-1A, Acceptable Methods, Techniques and

Practices; or other data that the FAA has approved for spar repair and

replacement.

    The NPRM was the result of in-flight wing structural failure on one

of the affected airplanes that was in compliance with the one-time

inspection requirement of AD 87-18-09, plus 4 other ACAC Model 8GCBC

accidents and 11 service difficulty reports (SDR's) of compression

cracked spars.

    Interested persons have been afforded an opportunity to participate

in the making of this amendment. One comment was received in support of

the NPRM, and another comment was received that suggests that the FAA

reconsider the NPRM. Due consideration has been given to the comment

that suggests that the FAA reconsider the NPRM. No comments were

received on the FAA's determination of the cost impact upon the public.



Comment Disposition



    The commenter believes that, based on years of experience and

involvement with operating the Model 8GCBC airplane, the NPRM is not

justified. The commenter explains that after 60,000 hours time-in-

service (TIS) over 9 years (roughly about 7,000 hours TIS annually), 4

of the 6 airplanes in the fleet that the commenter operates were

rebuilt to improve aesthetics and to give piece of mind that the

airplanes were in good operating condition. Upon refurbishing,

including inspections of the wood spars, no compression cracks in the

wing spars were found. The commenter went on to state that damage was

found as a result of a previous ground incident, but revealed no

compression cracking. The commenter feels the FAA should withdraw the

AD as currently written.

    The FAA does not concur. Based on all data received, the FAA

believes that wood spar compression cracks can occur with or without

previous wing damage. The data indicates that detection of a

compression crack on the sides of the spar is unlikely, unless the

crack is in an advanced state of propagation. The FAA does not issue

AD's based on individual operator's experiences. The FAA issues AD's

after analyzing all safety information that is based on the design of

the affected aircraft, such as testing, accident/incident reports, etc.

Based on all of this data, the FAA believes that repetitive inspections

are necessary and the proposed AD is necessary to assure the continued

airworthiness of these airplanes. No changes have been made to the

final rule based on this comment.



Revision to the Service Information



    Based on information received from the field, ACAC has revised

Service Letter 417 to the Revision B level (dated February 10, 1998).

This revision retains the pertinent information presented in the

original version of the service letter and Revision A to the service

letter, and adds optional borescope inspections and fabric patches in

place of removable covers. A recommendation to use optional removable

inspection covers is included in the service bulletin. The FAA has

determined that this revised service letter should be incorporated into

the AD.



The FAA's Determination



    After careful review of all available information related to the

subject



[[Page 10298]]



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

interest require the adoption of the rule as proposed except for the

addition of the service information described above and minor editorial

corrections. The FAA has determined that this addition and these minor

corrections will not change the meaning of the AD and will not add any

additional burden upon the public than was already proposed.



Difference Between This AD and ACAC Service Letter 406



    ACAC Service Letter 406, dated March 28, 1994, specifies the same

inspections as are required in this AD. The differences between the

service letter and the AD are:

    --The service letter specifies the required action within the next

30 days or 10 flight hours and at each 100 hour/annual inspection

thereafter. The FAA has determined that a more realistic compliance and

enforceable compliance time would be to require the action within 3

calendar months after the effective date of the AD, and thereafter at

intervals not to exceed 12 calendar months or 500 hours TIS, whichever

occurs first; and

    --The service letter applies to all ACAC 7 and 8 series airplanes,

whereas the AD applies only to ACAC Model 8GCBC airplanes. The FAA is

currently considering additional rulemaking action on the airplane

models other than the Model 8GCBC airplanes.



Compliance Time of This AD



    The compliance time of this AD is presented in calendar time and

hours TIS. Although the unsafe condition specified in this AD is a

result of airplane operation, the affected airplanes are utilized in

different ways.

    For example, an operator may utilize his/her airplane 50 hours TIS

in a year while utilizing the aircraft in no or very little crop

dusting operations, banner and glider tow operations, or rough field or

float operations. This airplane operator would obviously experience

less of a chance of high crack propagation than the airplane operator

that utilizes his/her airplane 300 hours TIS in a year regularly in

heavy crop dusting operations, banner and glider tow operations, or

rough field or float operations. However, this airplane could have pre-

existing and undetected wood spar damage that occurred during previous

operations. In this situation, the damage to the wood spar would

propagate at a level that depends on the operational exposure of the

airplane and severity of the wood spar damage.

    To assure that compression cracks do not go undetected on the wood

spars of the affected airplanes, the FAA has determined that an initial

3 calendar month compliance time should be used. Repetitive actions

will then be accomplished every 12 calendar months or 500 hours TIS,

whichever occurs first.



Cost Impact



    The FAA estimates that 261 airplanes in the U.S. registry will be

affected by this AD, that it will take approximately 8 workhours

(Installations: 7 workhours; Initial Inspection: 1 workhour) per

airplane to accomplish the required and optional action, and that the

average labor rate is approximately $60 an hour. Parts cost

approximately $170 per airplane, provided that each airplane would only

need 6 additional standard inspection hole covers per wing bottom

surface (total of 12 new covers per airplane) and 4 upper surface wing

covers. If the airplane would require the installation of more

inspection covers (i.e., a result of previous non-factory wing recover

work), the cost could be slightly higher. Based on these figures, the

total cost impact of this AD on U.S. operators is estimated to be

$169,650, or $650 per airplane.

    This cost figure is based on the presumption that no affected

airplane owner/operator has accomplished the installations or the

initial inspection. The FAA has no knowledge of any owner/operator of

the affected airplanes that has already accomplished the installations

and initial inspection.

    This cost figure also does not account for repetitive inspections.

The FAA has no way of determining the number of repetitive inspections

each owner/operator of the affected airplanes will incur over the life

of his/her airplane. However, each repetitive inspection will cost

substantially less than the initial inspection if accomplishing the

optional inspection hole and cover installations. The optional

inspection covers allow easy access for the inspection of the wood

spars, and the compliance time would enable the owners/operators of the

affected airplanes to accomplish the repetitive inspections at

regularly scheduled annual inspections.



Regulatory Impact



    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 copy of the final evaluation prepared for this

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

by contacting 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 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.



Sec. 39.13  [Amended]



    2. Section 39.13 is amended by adding a new airworthiness directive

(AD) to read as follows:



98-05-04  American Champion Aircraft Corp.: Amendment 39-10365;

Docket No. 97-CE-37-AD. Supersedes AD 87-18-09, Amendment 39-5725.



    Applicability: Model 8GCBC airplanes, all serial numbers,

certificated in any category, that are equipped with wood wing

spars.



    Note 1: This AD applies to each airplane identified in the

preceding applicability provision, regardless of whether it has been

modified, altered, repaired, or reconfigured in the area subject to

the requirements of this AD. For airplanes that have been modified,

altered, repaired, or reconfigured so that the performance of the

requirements of this AD is affected, the owner/operator must request

approval for an alternative method of compliance in accordance with

paragraph (e) of this AD. The request should include an assessment

of the effect of the modification, alteration, or repair on the

unsafe condition addressed by this AD; and, if the unsafe condition

has not been eliminated, the request should include specific

proposed actions to address it.



[[Page 10299]]



    Compliance: Required as indicated in the body of this AD, unless

already accomplished.

    To detect possible compression cracks and other damage in the

wood spar wing, which, if not corrected, could eventually result in

in-flight structural failure of the wing with consequent loss of the

airplane, accomplish the following:

    (a) Within the next 3 calendar months after the effective date

of this AD, accomplish the following:

    (1) Install inspection holes in the top and/or bottom surface of

each wing in accordance with American Champion Aircraft Corporation

(ACAC) Service Letter 417, Revision B, dated February 10, 1998. No

further action is required by this paragraph (paragraph (a)(1) of

this AD) if inspection holes are installed in accordance with ACAC

Service Letter 417, Revision A, dated October 2, 1997; or ACAC

Service Letter 417, dated August 14, 1997.

    (2) Inspect (detailed visual) both the front and rear wood wing

spars for cracks; compression cracks; longitudinal cracks through

the bolt holes or nail holes; and loose or missing nails (referred

to as damage hereon). Accomplish these inspections in accordance

with ACAC Service Letter 406, dated March 28, 1994.

    (3) If any spar damage is found, prior to further flight,

accomplish the following:

    (i) Repair or replace the wood wing spar in accordance with

Advisory Circular (AC) 43-13-1A, Acceptable Methods, Techniques and

Practices; or other data that is approved by the FAA for wing spar

repair or replacement.

    (ii) If the wing is recovered, accomplish the installations

required by paragraph (a)(1) of this AD, as applicable.

    (4) Install inspection hole covers or fabric patches, as

required, on the top and bottom surface of the wing in accordance

with ACAC Service Letter 417, Revision B, dated February 10, 1998.

No further action is required by this paragraph (paragraph (a)(4) of

this AD) if inspection hole covers are installed in accordance with

ACAC Service Letter 417, Revision A, dated October 2, 1997; or ACAC

Service Letter 417, dated August 14, 1997.

    (b) Within 12 calendar months or 500 hours time-in-service (TIS)

(whichever occurs first) after accomplishing all actions required by

paragraph (a), all subparagraphs included, of this AD, and

thereafter at intervals not to exceed 12 calendar months or 500

hours TIS, whichever occurs first, accomplish the inspection,

repair, replacement, and installation required by paragraphs (a)(2),

(a)(3), as applicable; including its subparagraphs; and (a)(4) of

this AD.



    Note 2: The affected airplanes are not certificated for

aerobatic maneuvers. AD 87-18-09 required a placard prohibiting

aerobatic maneuvers in addition to the existing operational placard.

The FAA encourages owners/operators of the affected airplanes to

keep this placard installed on their airplanes.



    (c) If any of the affected airplanes are involved in an incident

or accident involving wing damage after the effective date of this

AD, prior to further flight, accomplish the inspection, repair,

replacement, and installation required by paragraphs (a)(2), (a)(3),

as applicable; including its subparagraphs; and (a)(4) of this AD.

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

sections 21.197 and 21.199 of the Federal Aviation Regulations (14

CFR 21.197 and 21.199) to operate the airplane to a location where

the requirements of this AD can be accomplished.

    (e) An alternative method of compliance or adjustment of the

initial or repetitive compliance time that provides an equivalent

level of safety may be approved by the Manager, Chicago Aircraft

Certification Office (ACO), 2300 E. Devon Avenue, Des Plaines,

Illinois 60018.

    (1) The request shall be forwarded through an appropriate FAA

Maintenance Inspector, who may add comments and then send it to the

Manager, Chicago ACO.

    (2) Alternative methods of compliance approved in accordance

with AD 87-18-09 (superseded by this action) are not considered

approved as alternative methods of compliance for this AD.



    Note 3: Information concerning the existence of approved

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

obtained from the Chicago ACO.



    (f) The installation required by this AD shall be done in

accordance with American Champion Aircraft Corp. Service Letter 417,

Revision B, dated February 10, 1998; American Champion Aircraft

Corp. Service Letter 417, Revision A, dated October 2, 1997; or

American Champion Aircraft Corp. Service Letter 417, dated August

14, 1997. The inspections required by this AD shall be done in

accordance with American Champion Aircraft Corp. Service Letter 406,

dated March 28, 1994. 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 the American

Champion Aircraft Corp., P.O. Box 37, 32032 Washington Avenue,

Highway D, Rochester, Wisconsin 53167. Copies may be inspected at

the FAA, Central Region, Office of the Regional Counsel, Room 1558,

601 E. 12th Street, Kansas City, Missouri, or at the Office of the

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

Washington, DC.

    (g) This amendment (39-10365) supersedes AD 87-18-09, Amendment

39-5725.

    (h) This amendment (39-10365) becomes effective on April 17,

1998.



    Issued in Kansas City, Missouri, on February 23, 1998.

Marvin R. Nuss,

Acting Manager, Small Airplane Directorate, Aircraft Certification

Service.

[FR Doc. 98-5198 Filed 3-2-98; 8:45 am]

BILLING CODE 4910-13-P