AD Amdt-39-11262

final rule

Airworthiness Directives; Bombardier Model DHC-8 Series Airplanes

AD Number
Amdt-39-11262
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Docket No. 99-NM-55-AD
FR Citation
64 FR 45425
Technical illustration of an aircraft flight control surface and actuator
Problem area Flight controls

Applicability

TypeManufacturerModelDetails
aircraft Bombardier DHC-8 Airworthiness Directives; Bombardier Model DHC-8 Series Airplanes

Unsafe Condition

Asymmetric rudder force condition due to single rate configuration springs in the rudder control feel unit, which could reduce controllability and cause center line deviation.

AI-generated summary from the source AD text. Verify against the official source before acting.

Required Actions

Inspect spring assemblies in the rudder control feel unit to verify dual rate configuration springs are installed. Replace any single rate configuration springs with dual rate configuration springs. Revise the Airplane Flight Manual to prohibit operation from runways less than 75 feet wide, if necessary.

AI-generated summary from the source AD text. Verify against the official source before acting.

Compliance Time

Within 12 months of the effective date of the AD.

AI-generated summary from the source AD text. Verify against the official source before acting.

Affected Aircraft

Bombardier Model DHC-8 series airplanes with rudder control feel units containing single rate configuration springs.

AI-generated summary from the source AD text. Verify against the official source before acting.

Federal Register Abstract

This amendment adopts a new airworthiness directive (AD), applicable to certain Bombardier Model DHC-8 series airplanes, that requires a one-time inspection of the spring assemblies located in the rudder control feel unit to verify that dual rate configuration springs are installed; and revising the Airplane Flight Manual to prohibit airplane operation from runways less than 75 feet wide, if necessary. This amendment also requires eventual replacement of any single rate configuration springs with dual rate configuration springs, which terminates the requirement for the AFM revision. This amendment is prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified by this AD are intended to prevent an asymmetric rudder force condition, which could result in reduced controllability of the airplane and consequent potential for center line deviation.

Document Text

Show stored source text (verify against official source)
[Federal Register Volume 64, Number 161 (Friday, August 20, 1999)]
[Rules and Regulations]
[Pages 45425-45426]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 99-21362]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-NM-55-AD; Amendment 39-11262; AD 99-17-14]
RIN 2120-AA64


Airworthiness Directives; Bombardier Model DHC-8 Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment adopts a new airworthiness directive (AD), 
applicable to certain Bombardier Model DHC-8 series airplanes, that 
requires a one-time inspection of the spring assemblies located in the 
rudder control feel unit to verify that dual rate configuration springs 
are installed; and revising the Airplane Flight Manual to prohibit 
airplane operation from runways less than 75 feet wide, if necessary. 
This amendment also requires eventual replacement of any single rate 
configuration springs with dual rate configuration springs, which 
terminates the requirement for the AFM revision. This amendment is 
prompted by issuance of mandatory continuing airworthiness information 
by a foreign civil airworthiness authority. The actions specified by 
this AD are intended to prevent an asymmetric rudder force condition, 
which could result in reduced controllability of the airplane and 
consequent potential for center line deviation.

DATES: Effective September 24, 1999.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of September 24, 1999.

ADDRESSES: The service information referenced in this AD may be 
obtained from Bombardier, Inc., Bombardier Regional Aircraft Division, 
Garratt Boulevard, Downsview, Ontario M3K 1Y5, Canada. This information 
may be examined at the Federal Aviation Administration (FAA), Transport 
Airplane Directorate, Rules Docket, 1601 Lind Avenue, SW., Renton, 
Washington; at the FAA, Engine and Propeller Directorate, New York 
Aircraft Certification Office, 10 Fifth Street, Third Floor, Valley 
Stream, New York; or at the Office of the Federal Register, 800 North 
Capitol Street, NW., suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT: James E. Delisio, Aerospace Engineer, 
Airframe and Propulsion Branch, ANE-171, FAA, Engine and Propeller 
Directorate, New York Aircraft Certification Office, 10 Fifth Street, 
Third Floor, Valley Stream, New York 11581; telephone (516) 256-7521; 
fax (516) 568-2716.

SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal 
Aviation Regulations (14 CFR part 39) to include an airworthiness 
directive (AD) that is applicable to certain Bombardier Model DHC-8 
series airplanes was published in the Federal Register on June 22, 1999 
(64 FR 33232). That action proposed to require a one-time inspection of 
the spring assemblies located in the rudder control feel unit to verify 
that dual rate configuration springs are installed; and revising the 
Airplane Flight Manual to prohibit airplane operation from runways less 
than 75 feet wide, if necessary. That proposal also would require 
eventual replacement of any single rate configuration springs with dual 
rate configuration springs, which would terminate the requirement for 
the AFM revision.

Comments

    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. No comments were submitted in response 
to the proposal or the FAA's determination of the cost to the public.

Explanation of Change Made to Proposal

    The FAA has added a note to the final rule to clarify the 
definition of a general visual inspection.

Conclusion

    The FAA has determined that air safety and the public interest 
require the adoption of the rule as proposed.

Cost Impact

    The FAA estimates that 235 airplanes of U.S. registry will be 
affected by this AD.
    It will take approximately 1 work hour per airplane to accomplish 
the required inspection, at an average labor rate of $60 per work hour. 
Based on these figures, the cost impact of the inspection required by 
this AD on U.S. operators is estimated to be $14,100, or $60 per 
airplane.
    It will take approximately 10 work hours per airplane to accomplish 
the required replacement, at an average labor rate of $60 per work 
hour. Required parts will be provided by the manufacturer at no cost to 
the operators. Based on these figures, the cost impact of the 
replacement required by this AD on U.S. operators is estimated to be 
$141,000, or $600 per airplane.
    If accomplished, it will take approximately 1 work hour per 
airplane to accomplish the AFM revision, at an average labor rate of 
$60 per work hour. Based on these figures, the cost impact of the AFM 
revision on U.S. operators, if accomplished, is estimated to be 
$14,100, or $60 per airplane.
    The cost impact figures discussed above are based on assumptions 
that no operator has yet accomplished any of the proposed requirements 
of this AD action, and that no operator would accomplish those actions 
in the future if this AD were not adopted.

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,

[[Page 45426]]

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 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 the following new 
airworthiness directive:

99-17-14  Bombardier, Inc. (Formerly de Havilland, Inc.): Amendment 
39-11262. Docket 99-NM-55-AD.

    Applicability: Model DHC-8 series airplanes, as listed in 
Bombardier Alert Service Bulletin S.B. A8-27-82, dated July 10, 
1998; certificated in any category.
    Note 1: This AD applies to each airplane identified in the 
preceding applicability provision, regardless of whether it has been 
modified, altered, or repaired in the area subject to the 
requirements of this AD. For airplanes that have been modified, 
altered, or repaired 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 (d) 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.
    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent an asymmetric rudder force condition, which could 
result in reduced controllability of the airplane and consequent 
potential for center line deviation, accomplish the following:

General Visual Inspection

    (a) Within 100 flight hours or 14 days after the effective date 
of this AD, whichever occurs later: Perform a one-time visual 
inspection of the spring assemblies located in the rudder control 
feel unit to verify that dual rate configuration springs are 
installed, in accordance with Bombardier Alert Service Bulletin S.B. 
A8-27-82, dated July 10, 1998.
    (1) If dual rate configuration springs are installed, no further 
action is required by this AD.
    Note 2: For the purposes of this AD, a general visual inspection 
is defined as: ``A visual examination of an interior or exterior 
area, installation, or assembly to detect obvious damage, failure, 
or irregularity. This level of inspection is made under normally 
available lighting conditions such as daylight, hangar lighting, 
flashlight, or drop-light, and may require removal or opening of 
access panels or doors. Stands, ladders, or platforms may be 
required to gain proximity to the area being checked.''

AFM Revision

    (2) If any single rate configuration springs are installed, 
prior to further flight:
    Revise the Limitations Section of the de Havilland Dash 8 
Airplane Flight Manual (AFM) to include the following statement. 
This action may be accomplished by inserting a copy of this AD into 
the AFM.

``OPERATION FROM RUNWAYS LESS THAN 75 FEET WIDE IS PROHIBITED.''

Terminating Action

    (b) At the next scheduled maintenance visit, but no later than 
36 months after the effective date of this AD: Replace any single 
rate configuration springs located in the rudder control feel unit 
with dual rate configuration springs, in accordance with Part C 
through Part H inclusive, of the Accomplishment Instructions of 
Bombardier Alert Service Bulletin S.B. A8-27-82, dated July 10, 
1998. Such replacement constitutes terminating action for the 
requirements of this AD. After the replacement has been 
accomplished, the AFM limitation required by paragraph (a)(2) of 
this AD may be removed from the AFM.

Spares Paragraph

    (c) As of the effective date of this AD, no person shall install 
any spring assembly having part number 82760050-003 on any airplane.

Alternative Methods of Compliance

    (d) 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, New York Aircraft Certification 
Office (ACO), FAA, Engine and Propeller Directorate. Operators shall 
submit their requests through an appropriate FAA Principal 
Maintenance Inspector, who may add comments and then send it to the 
Manager, New York ACO.
    Note 3: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the New York ACO.

Special Flight Permits

    (e) Special flight permits may be issued in accordance with 
Secs. 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.

Incorporation by Reference

    (f) Except as provided by paragraph (a)(2), the actions shall be 
done in accordance with Bombardier Alert Service Bulletin S.B. A8-
27-82, dated July 10, 1998. 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 
Bombardier, Inc., Bombardier Regional Aircraft Division, Garratt 
Boulevard, Downsview, Ontario M3K 1Y5, Canada. Copies may be 
inspected at the FAA, Transport Airplane Directorate, 1601 Lind 
Avenue, SW., Renton, Washington; or at the FAA, Engine and Propeller 
Directorate, New York Aircraft Certification Office, 10 Fifth 
Street, Third Floor, Valley Stream, New York; or at the Office of 
the Federal Register, 800 North Capitol Street, NW., suite 700, 
Washington, DC.
    Note 4: The subject of this AD is addressed in Canadian 
airworthiness directives CF-98-39, dated October 23, 1998, and CF-
98-39R1, dated December 31, 1998.
    (g) This amendment becomes effective on September 24, 1999.

    Issued in Renton, Washington, on August 10, 1999.
D. L. Riggin, Acting
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 99-21362 Filed 8-19-99; 8:45 am]
BILLING CODE 4910-13-U

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