AD 2006-08-07
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Brantly International, Inc. | B-2 | Airworthiness Directives; Brantly International, Inc. Model B-2, B-2A, and B-2B Helicopters |
| aircraft | Brantly International, Inc. | B-2A | Airworthiness Directives; Brantly International, Inc. Model B-2, B-2A, and B-2B Helicopters |
| aircraft | Brantly International, Inc. | B-2B | Airworthiness Directives; Brantly International, Inc. Model B-2, B-2A, and B-2B Helicopters |
Unsafe Condition
Fatigue cracking of the vertical shaft, potentially caused by misalignment, leading to shaft failure and subsequent loss of control of the helicopter.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Inspect and measure the upper tail rotor vertical gearbox, vertical shaft, shaft housing, and associated parts, including the intermediate gearbox bushing. Replace any unairworthy parts found during inspection. Ensure proper alignment and installation of the gearbox, shaft, and housing without adjustment. Report discrepancies to the Rotorcraft Certification Office within 7 work days.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within 10 hours time-in-service (TIS) and before further flight after any hard landing or main/tail rotor sudden stoppage.
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Brantly International, Inc. Model B-2, B-2A, and B-2B helicopters, serial number 2001 and larger, or any helicopter with part number 249-10 installed and purchased after 1994.
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) for the specified Brantly International, Inc. (Brantly) model helicopters. This action requires certain inspections and measurements of the upper tail rotor vertical gearbox (gearbox), vertical shaft (shaft) and shaft housing (housing) and their associated parts; and of the intermediate gear box bushing (bushing). This amendment is prompted by an accident and an incident report of fatigue cracking of a shaft. The actions specified in this AD are intended to prevent fatigue cracking of a shaft, failure of a shaft, and subsequent loss of control of the helicopter.
Document Text
Show stored source text (verify against official source)
[Federal Register Volume 71, Number 73 (Monday, April 17, 2006)]
[Rules and Regulations]
[Pages 19624-19626]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 06-3536]
=======================================================================
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2006-24447; Directorate Identifier 2005-SW-35-AD;
Amendment 39-14562; AD 2006-08-07]
RIN 2120-AA64
Airworthiness Directives; Brantly International, Inc. Model B-2,
B-2A, and B-2B Helicopters
AGENCY: Federal Aviation Administration, DOT.
ACTION: Final rule; request for comments.
-----------------------------------------------------------------------
SUMMARY: This amendment adopts a new airworthiness directive (AD) for
the specified Brantly International, Inc. (Brantly) model helicopters.
This action requires certain inspections and measurements of the upper
tail rotor vertical gearbox (gearbox), vertical shaft (shaft) and shaft
housing (housing) and their associated parts; and of the intermediate
gear box bushing (bushing). This amendment is prompted by an accident
and an incident report of fatigue cracking of a shaft. The actions
specified in this AD are intended to prevent fatigue cracking of a
shaft, failure of a shaft, and subsequent loss of control of the
helicopter.
DATES: Effective May 2, 2006.
The incorporation by reference of certain publications listed in
the regulations is approved by the Director of the Federal Register as
of May 2, 2006.
Comments for inclusion in the Rules Docket must be received on or
before June 16, 2006.
ADDRESSES: Use one of the following addresses to submit comments on
this AD:
<bullet> DOT Docket Web site: Go to <a href="http://dms.dot.gov">http://dms.dot.gov</a> and follow
the instructions for sending your comments electronically;
<bullet> Government-wide rulemaking Web site: Go to <a href="http://www.regulations.gov">http://www.regulations.gov</a> and follow the instructions for sending your
comments electronically;
<bullet> Mail: Docket Management Facility; U.S. Department of
Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-401,
Washington, DC 20590;
<bullet> Fax: (202) 493-2251; or
<bullet> Hand Delivery: Room PL-401 on the plaza level of the
Nassif Building, 400 Seventh Street, SW., Washington, DC, between 9
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
You may get the service information identified in this AD from
Brantly International, Inc., Wilbarger County Airport, 12399 Airport
Drive, Vernon, Texas 76384, telephone 940-552-5451.
Examining the Docket
You may examine the docket that contains the AD, any comments, and
other information on the Internet at <a href="http://dms.dot.gov">http://dms.dot.gov</a>, or in person
at the Docket Management System (DMS) Docket Offices between 9 a.m. and
5 p.m., Monday through Friday, except Federal holidays. The Docket
Office (telephone (800) 647-5227) is located on the plaza level of the
Department of Transportation Nassif Building at the street address
stated in the ADDRESSES section. Comments will be available in the AD
docket shortly after the DMS receives them.
FOR FURTHER INFORMATION CONTACT: Marc Belhumeur, Aviation Safety
Engineer, FAA, Rotorcraft Directorate, Rotorcraft Certification Office,
Fort Worth, Texas 76193-0170, telephone (817) 222-5177, fax (817) 222-
5783.
SUPPLEMENTARY INFORMATION: This amendment adopts a new AD for the
specified Brantly model helicopters. This action requires certain
inspections and measurements of the gearbox, shaft, housing and their
associated parts; and of the bushing. This amendment is prompted by an
accident and an incident report of fatigue cracking of a shaft. The
fatigue cracking may have been caused by higher than expected loads,
most likely due to misalignment. Fatigue cracking of the shaft, if not
detected, could result in failure of the shaft and subsequent loss of
control of the helicopter.
We have reviewed Brantly Service Bulletin No. 105, Revision A,
dated August 3, 2005 (SB), which describe procedures for certain
inspections of the gearbox, shaft, housing, and bushing for
helicopters, serial number 2001 and larger, or any serial-numbered
helicopter with a shaft, part number (P/N) 249-10, installed, that was
purchased after 1994.
This unsafe condition is likely to exist or develop on other
helicopters of the same type design. Therefore, this AD is being issued
to prevent fatigue cracking of the shaft, failure of the shaft, and
subsequent loss of control of the helicopter. This AD requires, within
10 hours time-in-service (TIS) and before further flight after any hard
landing or any main or tail rotor sudden stoppage:
<bullet> Removing the gearbox, P/N 278-200; shaft, P/N 249-10;
housing, P/N 249-3; and the bushing, P/N 252-4.
<bullet> Inspecting and measuring the flange retainer, P/N 15-17,
and replacing the flange retainer with an airworthy flange retainer if
the part is deformed or if the inside diameter is not 1.5050 to 1.5060
inches.
<bullet> Inspecting and measuring the housing, P/N 249-3, and
replacing the housing with an airworthy housing if the part is deformed
or if any outer diameter not on the flared end is not 1.497 to 1.500
inches or if the outer diameter of the flared end is not 1.844 to 1.875
inches.
<bullet> Inspecting and measuring the bushing, P/N 252-4, and
replacing it if its length is not .292 to .302 inch or if nicks or
scoring is found.
<bullet> Inspecting and measuring the bevel pinion gear (gear), P/N
15-8, and replacing the gear with an airworthy gear if certain
conditions exist.
<bullet> Inspecting each vertical shaft attachment bolt, P/N 15-201
and P/N 249-11, measuring the grip diameter, and replacing any bolt
with an airworthy bolt if it has fretting or nicks or if the grip
diameter is not .1889 to .1894 inch.
<bullet> Inspecting the male coupling, P/N 249-9, and measuring the
bolt hole and bore diameter and replacing the male coupling with an
airworthy male coupling if certain conditions exist.
<bullet> Inspecting the shaft, P/N 249-10, for misalignment;
measuring the diameter of the bolt holes; inspecting for straightness
of the shaft; magnetic particle inspecting the shaft for a crack;
visually inspecting the shaft; and replacing the shaft if certain
conditions exist.
<bullet> Assembling and inspecting the gearbox, P/N 278-200, the
shaft, P/N 249-10, and the housing, P/N 249-3; inspecting the bore for
foreign objects or burrs before assembling the pinion gear and the male
coupling to the shaft; and replacing any unairworthy parts.
This AD further requires:
<bullet> Ensuring that the intermediate gearbox, P/N 278-100, its
cover, P/N 252-3, and the bushing, P/N 252-4, the long horizontal shaft
housing, P/N 14-13, and its retainer flange, P/N 15-17, are aligned and
bolted down without
[[Page 19625]]
any adjustment being made for the gearbox (upper), shaft (vertical), or
housing.
<bullet> Installing and inspecting the gearbox, P/N 278-200, and
correcting any installation that does not comply with the installation
tolerances.
<bullet> Following an airworthy installation of the gearbox,
inspecting the tail rotor rigging control and correcting it, if
necessary.
<bullet> Reporting discrepancies to the Rotorcraft Certification
Office within 7 work days. The inspections, installation procedures,
and assembly of the gearbox must be done by following the specified
portions of the SB described previously.
The short compliance time involved is required because the
previously described critical unsafe condition can adversely affect the
structural integrity and controllability of the helicopter. Therefore,
inspecting and measuring the gearbox, shaft, housing, and bushing are
required within 10 hours TIS. Also, replacing any unairworthy part
found during any inspection is required before further flight, so this
AD must be issued immediately.
Since a situation exists that requires the immediate adoption of
this regulation, it is found that notice and opportunity for prior
public comment hereon are impracticable, and that good cause exists for
making this amendment effective in less than 30 days.
This AD is an interim action that covers initial inspections and
measurements of the gearbox, shaft, housing, bushing, and their
associated parts. We plan to follow this AD with a superseding Notice
of Proposed Rulemaking to propose adding recurring 200-hour inspections
of the shaft until the cause of the shaft cracking can be determined.
We estimate that this AD will affect 194 helicopters, and
inspecting, measuring, and replacing the tail rotor drive system parts
will take about 13.4 work hours to accomplish at an average labor rate
of $65 per work hour, assuming the upper gearbox (which includes the
shaft) and the intermediate gearbox are replaced, which would be the
worst case scenario. Under this assumption, required parts will cost
approximately $5,775 (cost of the upper and the intermediate gearbox)
per helicopter. Based on these figures, we estimate the total cost
impact of the AD on U.S. operators to be $1,289,324.
Comments Invited
This AD is a final rule that involves requirements that affect
flight safety and was not preceded by notice and an opportunity for
public comment; however, we invite you to submit any written data,
views, or arguments regarding this AD. Send your comments to an address
listed under ADDRESSES. Include ``Docket No. FAA-2005-XXXXX;
Directorate Identifier 2005-SW-35-AD'' at the beginning of your
comments. We specifically invite comments on the overall regulatory,
economic, environmental, and energy aspects of the AD. We will consider
all comments received by the closing date and may amend the AD in light
of those comments.
We will post all comments we receive, without change, to <a href="http://dms.dot.gov">http://dms.dot.gov</a>, including any personal information you provide. We will
also post a report summarizing each substantive verbal contact with FAA
personnel concerning this AD. Using the search function of our docket
Web site, you can find and read the comments to any of our dockets,
including the name of the individual who sent the comment. You may
review the DOT's complete Privacy Act Statement in the Federal Register
published on April 11, 2000 (65 FR 19477-78), or you may visit <a href="http://dms.dot.gov">http://dms.dot.gov</a>.
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 the regulation:
1. Is not a ``significant regulatory action'' under Executive Order
12866;
2. Is not a ``significant rule'' under the 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.
We prepared an economic evaluation of the estimated costs to comply
with this AD. See the DMS to examine the economic evaluation.
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.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by
reference, Safety.
Adoption of the Amendment
0
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
0
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]
0
2. Section 39.13 is amended by adding a new airworthiness directive to
read as follows:
2006-08-07 Brantly Helicopter, Inc.: Amendment 39-14562. Docket No.
FAA-2006-24447; Directorate Identifier 2005-SW-35-AD.
Applicability: Model B-2, B-2A, and B-2B helicopters, serial
number 2001 and larger, with a vertical shaft (shaft), part number
(P/N) 249-10, or any serial-numbered helicopter with a shaft, P/N
249-10, that was purchased after 1994, certificated in any category.
Compliance: Required as indicated, unless accomplished
previously.
To detect fatigue cracking of the shaft and prevent failure of
the shaft and subsequent loss of control of the helicopter,
accomplish the following:
(a) Within the next 10 hours time-in-service (TIS) and before
further flight after any hard landing or any main or tail rotor
sudden stoppage:
(1) Remove the tail rotor vertical gearbox (gearbox), P/N 278-
200; shaft, P/N 249-10; vertical shaft housing (housing), P/N 249-3;
and the intermediate gearbox bushing (bushing), P/N 252-4, from the
helicopter.
(2) Inspect the flange retainer, part number (P/N) 15-17,
located at the top of the shaft housing for deformation and measure
the inside diameter. Before further flight, replace the flange
retainer with an airworthy flange retainer if the part is deformed
or if the inside diameter is not 1.5050 to 1.5060 inches.
(3) Inspect the housing, P/N 249-3, for deformation and measure
the outer diameter at each end and at the center of its span.
[[Page 19626]]
Replace the housing with an airworthy housing if:
(i) The housing is deformed;
(ii) Any outer diameter not on the flared end is not 1.497 to
1.500 inches; or
(iii) The outer diameter of the flared end is not 1.844 to 1.875
inches.
(4) Inspect the bushing, P/N 252-4, for nicks or scoring, and
measure the bushing's length. If the length of the bushing is not
.292 to .302 inch or if nicks or scoring is found, replace the
bushing with an airworthy bushing before further flight.
(5) Inspect the bevel pinion gear (gear), P/N 15-8, paying
particular attention to the bore, for nicks, scoring, burrs, or
misalignment. Measure the diameter of the bolt hole and the bore.
Before further flight, replace the gear with an airworthy gear if:
(i) You find misalignment,
(ii) You cannot remove all nicks, scoring, or burrs with light
hand polishing using Scotch Brite (maroon or white) and maintain all
tolerances and a 32 root mean square (rms) finish,
(iii) The diameter of the bolt hole is not .1894 to .1899 inch,
or
(iv) The bore diameter is not .6248 to .6250 inch.
(6) Inspect the shaft attachment bolt, P/N 15-201, that inserts
into the pinion, and the attachment bolt, P/N 249-11, that inserts
into the male coupling, for fretting or nicks in the area where the
bolts contact the shaft and measure the grip diameter. If a bolt has
fretting or nicks or if the grip diameter is not .1889 to .1894
inch, replace the bolt with an airworthy bolt before further flight.
(7) Inspect the male coupling, P/N 249-9, paying particular
attention to the bore for nicks, scoring, keyway elongation, burrs,
or misalignment and measure the bolt hole diameter and the bore
diameter. Before further flight, replace the male coupling with an
airworthy male coupling if:
(i) You find misalignment;
(ii) The keyway has elongation;
(iii) You cannot remove all nicks, scoring, or burrs with light
hand polishing using Scotch Brite (maroon or white) and maintain all
tolerances and a 32 rms finish;
(iv) The diameter of the bolt hole is not .1894 to .1899 inch;
or
(v) The bore diameter is not .6250 to .6260 inch.
(8) Inspect the shaft, P/N 249-10, for misalignment. Measure the
diameter of the bolt holes. Inspect for straightness of the shaft by
placing the shaft on a flat surface plate calibrated to work surface
accuracy tolerance of <plus-minus>.001 inch, rolling the shaft, and
measuring the greatest gap between the shaft and the flat surface
table. Magnetic particle inspect the shaft for a crack, paying
particular attention to the bolt holes. Visually inspect the shaft,
paying particular attention to a circular area of .500 inch radius
from the center of the bolt holes for the following damage: nicks,
scoring, fretting, burrs, or misalignment. Before further flight,
replace the shaft if:
(i) You find misalignment,
(ii) You cannot remove all nicks, scoring, fretting, or burrs
with light hand polishing using Scotch Brite (maroon or white) and
maintaining all tolerances and a 32 rms finish,
(iii) The diameter of the bolt hole is not .1894 to .1899 inch,
(iv) The outer diameter of the shaft is not .6240 to .6250 inch
at all points,
(v) The shaft is not straight and the maximum gap between the
shaft and the flat surface table exceeds .007 inch, or
(vi) You find a crack, a surface or subsurface discontinuity, or
pitting.
(9) Assemble and inspect the gearbox, P/N 278-200, the shaft, P/
N 249-10, and the housing, P/N 249-3, by following Part 2, paragraph
2.6 of Brantly International Inc. Service Bulletin No. 105, Revision
A, dated August 3, 2005 (SB). Before assembling the pinion gear and
the male coupling to the shaft, thoroughly inspect the bore for
foreign objects or burrs. Clean and deburr the bore. If the assembly
fails any inspection required by this paragraph, replace the
gearbox, shaft, and housing with airworthy parts before further
flight and before complying with the remainder of this AD. When the
SB uses the term ``check'', for purposes of this AD, it means
``inspect.'' Also, you are not required to contact the factory as
stated in the SB.
(b) Before installing the gearbox (upper):
(i) Align and bolt down the intermediate gearbox, P/N 278-100,
its cover, P/N 252-3, and the bushing, P/N 252-4, the long
horizontal shaft housing, P/N 14-13, and its retainer flange, P/N
15-17, without making any adjustment for the gearbox (upper), shaft
(vertical), or housing.
Note 1: See the applicable maintenance manual for installation
instructions.
(c) Before further flight, install and inspect the gearbox, P/N
278-200, by following paragraphs 2.7 1) through 4) and Figure SB-
105-2 of the SB. If the gearbox fails any portion of the
installation procedures or any inspection tolerance required by this
paragraph, the installation is not airworthy and the helicopter is
grounded until the installation complies with the requirements of
this paragraph.
(d) After an airworthy installation of the gearbox is complete,
inspect the tail rotor rigging control and correct it, if necessary,
before further flight.
Note 2: See the applicable maintenance manual for tail rotor
control rigging instructions.
(e) Within 7 work days of conducting the inspections and
measuring the affected parts, report any discrepancies for the item
listed in Appendix A of this AD to the Rotorcraft Certification
Office at the address specified in Appendix A. Information
collection requirements contained in this AD have been approved by
the Office of Management and Budget (OMB) under the provisions of
the Paperwork Reduction Act of 1995 (44 U.S.C. 3501 et seq.) and
have been assigned OMB Control Number 2120-0056.
(f) To request a different method of compliance or a different
compliance time for this AD, follow the procedures in 14 CFR 39.19.
Contact the Rotorcraft Certification Office, FAA, for information
about previously approved alternative methods of compliance.
(g) Assemble, inspect, and install the gearbox and associated
parts by following the specified portions of the instructions in
Brantly International, Inc. Service Bulletin No. 105, Revision A,
dated August 3, 2005. The Director of the Federal Register approved
this incorporation by reference in accordance with 5 U.S.C. 552(a)
and 1 CFR part 51. Copies may be obtained from Brantly
International, Inc., Wilbarger County Airport, 12399 Airport Drive,
Vernon, TX 76384, telephone 940-552-5451. Copies may be inspected at
the National Archives and Records Administration (NARA). For
information on the availability of this material at NARA, call 202-
741-6030, or go to: <a href="http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html">http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html</a>.
Appendix A--Results of Gearbox Assembly Inspection and Wear
Measurements for the Brantly Model B-2, B-2A, and B-2B, Helicopters
Point of Contact Information:
Name:-----------------------------------------------------------------
Company Name:---------------------------------------------------------
Address:--------------------------------------------------------------
City/State/Zip:-------------------------------------------------------
Telephone:------------------------------------------------------------
Gearbox Part Inspection and Measurement Information (Report any
discrepancies found per the AD):---------------------------------------
Flange Retainer part number (P/N) 15-17-------------------------------
Shaft Housing, P/N 249-3----------------------------------------------
Bushing, P/N 252-4----------------------------------------------------
Bevel Pinion, P/N 15-8------------------------------------------------
Bolt, P/N 15-201------------------------------------------------------
Bolt 249-11-----------------------------------------------------------
Male Coupling, P/N 249-9----------------------------------------------
Shaft, P/N 249-10-----------------------------------------------------
Tail Rotor Gearbox Assembly, P/N 278-200------------------------------
Installation of Tail Rotor Gearbox Assembly---------------------------
Mail or Fax Results to: Federal Aviation Administration, ATTN:
Marc Belhumeur, Rotorcraft Certification Office, Fort Worth, TX
76193-0170, FAX: (516) 222-5783.
(h) This amendment becomes effective on May 2, 2006.
Issued in Fort Worth, Texas, on April 5, 2006.
David A. Downey,
Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 06-3536 Filed 4-14-06; 8:45 am]
BILLING CODE 4910-13-P
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