AD 2011-22-08
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | MD Helicopters, Inc. | MD900 | Airworthiness Directives; MD Helicopters, Inc. Model MD900 Helicopters |
Unsafe Condition
Failure of the Vertical Stabilizer Control System (VSCS) tube adapter, part number 500N7218-1, could lead to loss of yaw control 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
Turn ON both VSCS switches. De-energize the autopilot (AP/SAS) by centering the trim actuators, turning off the AP/SAS MSTR switch, and pulling specific circuit breakers. Install placards for AP/SAS deactivation and airspeed limitation. Revise the Rotorcraft Flight Manual (RFM) for limitations and emergency procedures. Alternatively, replace both VSCS tube adapters with newly-designed airworthy adapters, P/N 900C2010303-101, to terminate the AD requirements.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Before further flight
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
MD Helicopters, Inc. Model MD900 helicopters with a Vertical Stabilizer Control System (VSCS) tube adapter, part number 500N7218-1, installed, certificated in any category.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
This amendment supersedes an existing airworthiness directive (AD) that applies to MD Helicopters, Inc. (MDHI) Model MD900 helicopters. That AD currently requires turning ON both Vertical Stabilizer Control System (VSCS) switches and turning OFF the autopilot (AP/SAS) switch; pulling certain AP/SAS circuit breakers; installing a placard near the AP/SAS master switch; installing an airspeed limitation placard on the instrument panel; and making changes to the Rotorcraft Flight Manual (RFM). This amendment retains those requirements and provides an option of replacing each affected tube adapter with a newly-designed tube adapter, which provides terminating action for the unsafe condition. This amendment is prompted by the manufacturer introducing an improved, newly-designed tube adapter. The actions specified by this AD are intended to prevent loss of yaw control and subsequent loss of control of the helicopter.
Document Text
Show stored source text (verify against official source)
[Federal Register Volume 76, Number 216 (Tuesday, November 8, 2011)]
[Rules and Regulations]
[Pages 69123-69125]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2011-28897]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2010-1301; Directorate Identifier 2010-SW-008-AD;
Amendment 39-16851; AD 2011-22-08]
RIN 2120-AA64
Airworthiness Directives; MD Helicopters, Inc. Model MD900
Helicopters
AGENCY: Federal Aviation Administration, DOT.
ACTION: Final rule.
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[[Page 69124]]
SUMMARY: This amendment supersedes an existing airworthiness directive
(AD) that applies to MD Helicopters, Inc. (MDHI) Model MD900
helicopters. That AD currently requires turning ON both Vertical
Stabilizer Control System (VSCS) switches and turning OFF the autopilot
(AP/SAS) switch; pulling certain AP/SAS circuit breakers; installing a
placard near the AP/SAS master switch; installing an airspeed
limitation placard on the instrument panel; and making changes to the
Rotorcraft Flight Manual (RFM). This amendment retains those
requirements and provides an option of replacing each affected tube
adapter with a newly-designed tube adapter, which provides terminating
action for the unsafe condition. This amendment is prompted by the
manufacturer introducing an improved, newly-designed tube adapter. The
actions specified by this AD are intended to prevent loss of yaw
control and subsequent loss of control of the helicopter.
DATES: Effective December 13, 2011.
ADDRESSES: You may get the service information identified in this AD
from MD Helicopters, Inc., Attn: Customer Support Division, 4555 E.
McDowell Rd., Mail Stop M615, Mesa, AZ 85215-9734, telephone 1-(800)
388-3378, fax (480) 346-6813, or at <a href="http://www.mdhelicopters.com">http://www.mdhelicopters.com</a>.
Examining the Docket: You may examine the docket that contains this
AD, any comments, and other information on the Internet at <a href="http://www.regulations.gov">http://www.regulations.gov</a>, or at the Docket Operations office, West Building
Ground Floor, Room W12-140, 1200 New Jersey Avenue SE., Washington, DC.
FOR FURTHER INFORMATION CONTACT: Eric D. Schrieber, FAA, Los Angeles
Aircraft Certification Office, Aviation Safety Engineer, Airframe
Branch, 3960 Paramount Blvd., Lakewood, California 90712, telephone
(562) 627-5348, fax (562) 627-5210.
SUPPLEMENTARY INFORMATION:
Discussion
On December 28, 2010, we issued a proposal to amend part 39 of the
Federal Aviation Regulations (14 CFR part 39) to include an AD that
would apply to all MDHI Model MD900 helicopters with a VSCS tube
adapter, part number 500N7218-1, installed. This proposal was published
in the Federal Register as a notice of proposed rulemaking (NPRM) on
January 14, 2011 (76 FR 2607). The NPRM proposed to supersede AD 2008-
22-53 (73 FR 73165, December 2, 2008), retain the current requirements,
and require continuing operations at a reduced speed until each tube
adapter is replaced with an improved tube adapter.
We provided the public the opportunity to participate in developing
this AD. We received no comments on the proposal or on the
determination of the cost to the public. We have determined that air
safety and the public interest require adopting the AD as proposed.
We estimate that this AD will affect 39 helicopters of U.S.
registry. It will take about 5.5 hours to install the newly designed
tube adapters and 0.5 hours for all other required modifications at an
average labor rate of $85 per work hour. Required parts will cost about
$244 for 2 tube adapters. Based on these figures, we estimate the total
cost impact of this AD on U.S. operators is $29,406, assuming both tube
adapters are replaced on the entire fleet of helicopters.
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 AD docket 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
Accordingly, under 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. The FAA amends Sec. 39.13 by removing Amendment 39-15756 (73 FR
73165, December 2, 2008), and adding the following new AD:
2011-22-08 MD Helicopters, Inc. Model MD900 Helicopters: Amendment
39-16851; Docket No. FAA-2010-1301; Directorate Identifier 2010-SW-
008-AD. Supersedes AD 2008-22-53, Amendment 39-15756 (73 FR 73165,
December 2, 2008), Directorate ID 2008-SW-61-AD.
Applicability
Model MD900 helicopters with a Vertical Stabilizer Control
System (VSCS) tube adapter, part number (P/N) 500N7218-1, installed,
certificated in any category.
Compliance
Required before further flight, unless accomplished previously.
To prevent loss of yaw control and subsequent loss of control of
the helicopter, do the following:
(a) Turn ON both VSCS switches.
(b) If installed, de-energize the autopilot (AP/SAS) as follows:
(1) Determine if the AP/SAS trim actuators are centered. If the
AP/SAS trim actuators are not centered, center them.
(2) After the AP/SAS trim actuators are centered:
(i) Turn the AP/SAS MSTR switch to the OFF position.
(ii) Pull the following AP circuit breakers located on the A601
Essential Bus Circuit Breaker Panel, mounted in the cockpit console,
and install a plastic cable tie on each circuit breaker to prevent
accidental energizing of the circuit:
(A) AP/SAS CMPTR (CB28),
(B) AP/SAS DISC (CB29), and
(C) AP/SAS ACCEL (CB30).
[[Page 69125]]
(3) Install a placard next to the AP Mode Select panel that
contains the AP/SAS MSTR switch stating ``AP/SAS DEACTIVATED.''
(c) Install a placard on the instrument panel as close as
practicable to the airspeed indicator that states:
``AIRSPEED LIMIT 100 KIAS or V<INF>NE</INF>, WHICHEVER IS LESS.
VFR FLIGHT ONLY, AUTOPILOT OFF.''
(d) Make pen and ink changes or insert a copy of this AD into
the Limitations section of the rotorcraft flight manual (RFM) to
revise the limitations as follows: ``V<INF>NE</INF> is limited to
100 KIAS or less as determined by referring to the airspeed
V<INF>NE</INF> placard already installed on the helicopter. VFR
Flight Only, Autopilot OFF.''
(e) Make pen and ink changes or insert a copy of this AD into
the Limitations section of the RFM to revise the emergency
procedures as follows: ``If you experience an anti-torque system
malfunction, turn both VSCS switches to OFF during final approach
for a run-on landing.''
(f) Instead of complying with paragraphs (a) through (e) of this
AD, you may replace both VSCS tube adapters, P/N 500N7218-1, with
airworthy VSCS tube adapters, P/N 900C2010303-101. If you install
VSCS tube adapters, P/N 900C2010303-101, and previously have
complied with AD 2008-22-53 (73 FR 73165, December 2, 2008), return
the helicopter to its normal configuration by returning the switches
and circuit breakers to their normal operating position,
operationally testing the auto-pilot system, removing the two
placards, and removing the revisions to the RFM pertaining to the
airspeed limitation. Replacing both VSCS tube adapters, P/N
500N7218-1, with airworthy VSCS tube adapters, P/N 900C2010303-101,
and returning the helicopter to its normal operating configuration
constitutes terminating action for the requirements of this AD.
Note: MD Helicopters Service Bulletin SB900-110R1, dated
December 3, 2008, which is not incorporated by reference, contains
additional information about the subject of this AD. Copies of this
service information may be obtained from MD Helicopters, Inc., Attn:
Customer Support Division, 4555 E. McDowell Rd., Mail Stop M615,
Mesa, Arizona 85215-9734, telephone 1-(800) 388-3378, fax (480) 346-
6813, or on the Web at <a href="http://www.mdhelicopters.com">http://www.mdhelicopters.com</a>. This service
information may be inspected at the FAA, Office of the Regional
Counsel, Southwest Region, 2601 Meacham Blvd., Room 663, Fort Worth,
Texas 76137.
(g) 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 Manager, Los Angeles Aircraft Certification Office, FAA,
Attn: Eric D. Schrieber, Aviation Safety Engineer, Airframe Branch,
3960 Paramount Blvd., Lakewood, California 90712, telephone (562)
627-5348, fax (562) 627-5210, for information about previously
approved alternative methods of compliance.
(h) The Joint Aircraft System/Component (JASC) Code is 6720:
Tail Rotor Control System.
(i) This amendment becomes effective on December 13, 2011.
Issued in Fort Worth, Texas, on October 18, 2011.
Lance T. Gant,
Acting Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 2011-28897 Filed 11-7-11; 8:45 am]
BILLING CODE 4910-13-P
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Retrieved: Apr 6, 2026
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