[Federal Register Volume 59, Number 164 (Thursday, August 25, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-20906]


[[Page Unknown]]

[Federal Register: August 25, 1994]


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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 94-CE-05-AD; Amendment 39-9017; AD 94-18-04]

 

Airworthiness Directives; Univair Aircraft Corporation Models 
Ercoupe 415-C, 415-CD, 415-D, 415-E, and 415-G, Forney F-1 and F-1A, 
Alon A-2 and A-2A, and Mooney M10 Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment adopts a new airworthiness directive (AD) that 
applies to Univair Aircraft Corporation (Univair) Models Ercoupe 415-C, 
415-CD, 415-D, 415-E, and 415-G, Forney F-1 and F-1A, Alon A-2 and A-
2A, and Mooney M10 airplanes. This action requires installing 
inspection openings in the outer wing panels, inspecting (one-time) the 
wing outer panel structure for corrosion, and repairing any corrosion 
found. Several reports of corrosion in the outer wing panels of the 
affected airplanes prompted the proposed action. The actions specified 
by this AD are intended to prevent wing structural damage, that, if not 
detected and corrected, could progress to the point of failure.

DATES: Effective October 7, 1994.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of October 7, 1994.

ADDRESSES: Service information that applies to this AD may be obtained 
from the Univair Aircraft Corporation, 2500 Himalaya Road, Aurora, 
Colorado 80011; telephone (303) 375-8882; facsimile (303) 375-8888. 
This information may also be examined at the Federal Aviation 
Administration (FAA), Central Region, Office of the Assistant Chief 
Counsel, 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. Roger P. Chudy, Aerospace 
Engineer, FAA, Denver Aircraft Certification Field Office, 5440 Roslyn 
Street, suite 133, Denver, Colorado 80216; telephone (303) 286-5684; 
facsimile (303) 286-5689.

SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal 
Aviation Regulations (14 CFR part 39) to include an AD that would apply 
to certain Univair Models Ercoupe 415-C, 415-CD, 415-D, 415-E, and 415-
G, Forney F-1 and F-1A, Alon A-2 and A-2A, and Mooney M10 airplanes was 
published in the Federal Register on April 12, 1994 (59 FR 17288). The 
action proposed to require installing inspection openings in the outer 
wing panels, inspecting (one-time) the wing outer panel structure for 
corrosion, and repairing any corrosion found. The proposed actions 
would be accomplished in accordance with Univair Service Bulletin (SB) 
No. 29, dated January 27, 1994.
    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. Due consideration has been given to 
the three comments received from one commenter.
    The commenter states that installing inspection openings forward of 
the main spar constitutes a major change to the aircraft wing airfoil 
that would affect stall/spin characteristics, and requests the FAA 
delete these particular inspection openings from the AD. The FAA does 
not concur. The analysis accomplished by the Univair Aircraft Company 
in developing the service bulletin shows that the 15 percent chord 
placement of the inspection openings on the bottom wing surface is in a 
positive pressure zone well aft of the travel range of the forward 
stagnation point throughout the flight envelope. In addition, the FAA 
has not received any service difficulty reports or adverse comments 
from any of the affected airplane operators that have installed these 
inspection openings. The AD is unchanged as a result of this comment.
    This same commenter believes that 16 inspection openings is 
excessive and that a accurate appraisal of corrosion can be made with 
just the inspection openings aft of the main spar. The commenter 
recommends deleting the requirement for installing inspection openings 
forward of the main spar. The FAA does not concur. Corrosion in a wing 
is not necessarily a widespread condition. Corrosion may occur as a 
localized effect (example: corrosion induced by rodent urine) forward 
of the main spar and may not be visible through the aft openings until 
a critical deterioration has occurred. The FAA has examined the 
analysis of the Univair Aircraft Corporation and has determined that 
the number and placement of the inspection openings on an outer wing 
panel was developed carefully, accurately, and provides the proper 
assurance that corrosion can be adequately detected before structural 
deterioration. The AD is unchanged as a result of this comment.
    This commenter also suggests a different approach to the solution 
of the problem, one consisting of developing a service bulletin that 
recommends the installation of inspection openings over a certain 
period of time, say five years, after opening and recovering a wing. 
The commenter notes that there are many older aircraft with larger 
surfaces with fewer inspection openings than that which would be 
required by this AD. The FAA does not concur. The Univair Aircraft 
Corporation considered an extended time allowance after recovering the 
wing for installing inspection openings, but decided against it because 
there are two many variables in establishing a fleetwide implementation 
program. One must account for other factors to determine the 
appropriate time period to start an inspection program, including age 
and condition of the structure at the time of recover, operational and 
environmental conditions that the aircraft is subjected to, and the 
possible damage to the wing panels caused by the intrusion of insects 
or rodents. All of these factors led the FAA to implement the 
inspection opening installation requirements in conjunction with a one-
time inspection as proposed by the service bulletin in order to assure 
that the wing panels are airworthy from a corrosion standpoint upon 
completion of this AD. The installation openings provide a means for 
continuing routine inspections in the future. While older airplanes 
with larger wing surfaces may have fewer inspection openings than that 
which is specified in this AD, the FAA looked at the unique structural 
configuration of the wing panels for the affected airplane models in 
approving the type certificate holder's findings on the number and 
placement of the openings. The AD is unchanged as a result of the above 
comment.
    The Univair Aircraft Corporation has revised SB No. 29 to the 
Revision A level. This revision specifies a different screw used to 
secure the cover plate on airplanes with metal skinned wings. The FAA 
has determined that Univair SB No. 29, Revision A, dated June 7, 1994, 
should be incorporated into the final rule. Airplane owners/operators 
that have complied with the original version of this service bulletin 
will not have to re-accomplish these actions.
    After careful review of all available information including the 
comments referenced above, the FAA has determined that air safety and 
the public interest require the adoption of the rule as proposed except 
for the incorporation of the referenced service bulletin revision and 
minor editorial corrections. The FAA has determined that the service 
bulletin change and the minor corrections will not change the meaning 
of the AD nor add any additional burden upon the public than was 
already proposed.
    The compliance time for this AD is in calendar time instead of 
hours time-in-service (TIS). The FAA has determined that a calendar 
time for compliance is the most desirable method because the unsafe 
condition described by this AD is caused by corrosion. Corrosion can 
occur on airplanes regardless of whether the airplane is in service or 
in storage. Therefore, to ensure that corrosion is detected and 
corrected on all affected airplanes within a reasonable period of time 
without inadvertently grounding any airplane, a compliance schedule 
based upon calendar time instead of hours TIS is utilized.
    The FAA estimates that 2,672 airplanes in the U.S. registry will be 
affected by this AD, that it will take approximately 8 workhours per 
airplane to accomplish the required action, and that the average labor 
rate is approximately $55 an hour. Parts cost approximately $67 
(maximum) per airplane. Based on these figures, the total cost impact 
of the AD on U.S. operators is estimated to be $1,354,704. This figure 
is based on the assumption that no affected airplane owner/operator has 
accomplished the required action. The $67 parts cost figure is the 
maximum an operator will spend. Many airplane owners/operators will 
spend much less than this, and some airplane owners/operators have 
already accomplished the required action. With this in mind, the FAA 
believes the future cost impact estimate to be much less than that 
presented above.
    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. 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 adding a new AD to read as follows:

94-18-04 Univair Aircraft Corporation: Amendment 39-9017; Docket No. 
94-CE-05-AD.

    Applicability: Models Ercoupe 415-C, 415-CD, 415-D, 415-E, and 
415-G, Forney F-1 and F-1A, Alon A-2 and A-2A, and Mooney M10 
airplanes (all serial numbers), certificated in any category.
    Compliance: Required within the next 12 calendar months after 
the effective date of this AD, unless already accomplished (See Note 
1).
    To prevent wing structural damage that, if not detected and 
corrected, could progress to the point of failure, accomplish the 
following:
    (a) Install inspection openings in the outer wing panels and 
inspect the wing outer panel internal structural components for 
corrosion in accordance with the PROCEDURE section of Univair 
Service Bulletin No. 29, Revision A, dated June 7, 1994. Prior to 
further flight, repair any corrosion in accordance with instructions 
contained in the above-referenced service information.

    Note 1: Complying with the original version of Univair SB No. 
29, dated January 27, 1994, is considered equivalent to the 
requirements of paragraph (a) of this AD, and is considered ``unless 
already accomplished'' for this portion of the AD.

    (b) Send the results of the inspection required by paragraph (a) 
of this AD to the Manager, Denver Aircraft Certification Field 
Office, 5440 Roslyn Street, suite 133, Denver, Colorado 80216. State 
whether corrosion was found, the location and extent of any 
corrosion found, and the total hours TIS of the component at the 
time the corrosion was found. (Reporting approved by the Office of 
Management and Budget under OMB no. 2120-0056.)
    (c) 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.
    (d) An alternative method of compliance or adjustment of the 
compliance time that provides an equivalent level of safety may be 
approved by the Manager, Denver Aircraft Certification Field Office, 
5440 Roslyn Street, suite 133, Denver, Colorado 80216. The request 
shall be forwarded through an appropriate FAA Maintenance Inspector, 
who may add comments and then send it to the Manager, Denver 
Aircraft Certification Field Office.

    Note 2: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Denver Aircraft Certification Field Office.

    (e) The inspection and installation required by this AD shall be 
done in accordance with Univair Service Bulletin No. 29, Revision A, 
dated June 7, 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 Univair 
Aircraft Corporation, 2500 Himalaya Road, Aurora, Colorado 80011. 
Copies may be inspected at the FAA, Central Region, Office of the 
Assistant Chief 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.
    (f) This amendment (39-9017) becomes effective on October 7, 
1994.

    Issued in Kansas City, Missouri, on August 19, 1994.
Gerald W. Pierce,
Acting Manager, Small Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 94-20906 Filed 8-24-94; 8:45 am]
BILLING CODE 4910-13-P