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Published 2017-08-21 · Federal Register document 2017-17085

Airworthiness Directives; MD Helicopters, Inc., Helicopters

Publication summary

We are superseding Airworthiness Directive (AD) 2014-16-01 for MD Helicopters, Inc. (MDHI), Model MD900 helicopters. AD 2014-16-01 required an eddy current inspection of the main rotor upper hub assembly (upper hub) for a crack. This AD requires additional inspections and replacing the fillet seal. This AD was prompted by three additional reports of upper hub cracks. The actions of this AD are intended to prevent an unsafe condition on these products.

Why this record is shown

Source: Federal Register annual FAA metadata. Acquired 2026-09-03T22:23:54.997910+00:00. The title, summary and date are source facts.

Source revision
federal_register_ad_metadata_2017-90ba553c3b802c53
Source row
results[235]
Raw source SHA-256
90ba553c3b802c5316e8d18f30db5da9f7731a87f58278ec2965f199ef4375e9

Final-rule publication

Recorded publication clauses

AD identifier printed in this edition
2017-17-03
Effective date printed in this edition
2017-09-25
Read 9 complete recorded clauses
Applicability wording · Applicability
(a) Applicability

    This AD applies to Model MD900 helicopters with main rotor upper 
hub assembly (upper hub) part number 900R2101006-105, -107, -109, or 
-111 installed, certificated in any category.

Exact source excerpt. Text positions 9370–9576, end exclusive, in the original decoded publication. SHA-256: b474b3e4b1d44a790aa93faa638532fa80319e06db834675540c40b4c5f9e8cf

Unsafe Condition
(b) Unsafe Condition

    This AD defines the unsafe condition as a cracked upper hub. 
This condition could result in failure of the upper hub and 
subsequent loss of control of the helicopter.

Exact source excerpt. Text positions 9576–9772, end exclusive, in the original decoded publication. SHA-256: e01d9f94c30706392f3a2a2152b6d6652c07df6fc386720effc0a89ef84af723

Affected ADs
(c) Affected ADs

    This AD supersedes AD 2014-16-01, Amendment 39-17925 (79 FR 
45322, August 5, 2014).

Exact source excerpt. Text positions 9772–9880, end exclusive, in the original decoded publication. SHA-256: 3a9c105458e3b9011fd5653de39080d34f97870b2643c095f28d35d2b2a64d5c

Effective Date
(d) Effective Date

    This AD becomes effective September 25, 2017.

Exact source excerpt. Text positions 9880–9951, end exclusive, in the original decoded publication. SHA-256: 5c1094a6da817c9a425e65249ad048289ade30e9b526d0ef5ad6d2a495dd60b1

Compliance
(e) Compliance

    You are responsible for performing each action required by this 
AD within the specified compliance time unless it has already been 
accomplished prior to that time.

Exact source excerpt. Text positions 9951–10138, end exclusive, in the original decoded publication. SHA-256: 192f462f909366555355dd3c6e82ec63e03a370f4976da980a3788456069d652

Required Actions
(f) Required Actions

    (1) Within 100 hours time-in-service (TIS), and thereafter at 
intervals not to exceed 100 hours TIS:
    (i) Inspect the fillet seal around each flexbeam bolthole to 
determine whether it adheres properly to the hub or bushing or is 
missing. Indications of an improperly

[[Page 39525]]

adhered seal include lifting, bubbling, peeling away, drying out, or 
cracking. If the fillet seal is not properly adhered or is missing, 
before further flight, replace the fillet seal with sealant C232 or 
equivalent by following the Accomplishment Instructions, paragraphs 
2.D.(2) through 2.D.(5) and Figure 1, of MD Helicopters Service 
Bulletin SB900-125, dated February 19, 2016 (SB900-125).
    (ii) Using a light and a 10X or higher power magnifying glass, 
inspect the area outside of the fillet seal around each flexbeam 
bolthole on the top of the upper hub assembly for a crack. If there 
is a crack, before further flight, replace the upper hub assembly.
    (2) Within 12 months, and thereafter at intervals not to exceed 
12 months:
    (i) Remove the paint and primer from the area around each 
flexbeam bolthole on top of the upper hub. Remove the fillet seal 
from the mating surface of each bushing and the top of the upper 
hub.
    (ii) Using a light and a 10X or higher power magnifying glass, 
inspect the area around each flexbeam bolthole for a crack. If there 
is a crack, before further flight, replace the upper hub assembly.
    (iii) Inspect each lead leg shim and bushing for corrosion 
around the flexbeam boltholes on the bottom of the upper hub in the 
flexbeam pockets. If there is corrosion, before further flight:
    (A) Remove the lead leg shim from the flexbeam pocket and clean 
the area adjacent to the flexbeam bolthole to remove any corrosion 
within maximum repair damage limits. If the corrosion exceeds 
maximum repair damage limits, replace the upper hub assembly.
    (B) Using a light and a 10X or higher power magnifying glass, 
inspect the area around the flexbeam bolthole for a crack. If there 
is a crack, before further flight, replace the upper hub assembly.
    (iv) Replace the fillet seal as described in paragraph (f)(1)(i) 
of this AD.
    (3) Within 1,000 hours TIS, and thereafter at intervals not to 
exceed 1,000 hours TIS:
    (i) Eddy current inspect the areas adjacent to each flexbeam 
bolthole, top and bottom, for a crack. This eddy current inspection 
must be performed by a Level II or higher technician with the 
American Society for Nondestructive Testing ASNT-TC-1A, European 
Committee for Standardization CEN EN 4179, Military Standard MIL-
STD-410, National Aerospace Standard NAS410, or equivalent 
certification who has performed an eddy current inspection within 
the last 12 months. If there is a crack, before further flight, 
replace the upper hub assembly.
    (ii) Replace the fillet seal as described in paragraph (f)(1)(i) 
of this AD.

Exact source excerpt. Text positions 10138–13082, end exclusive, in the original decoded publication. SHA-256: 542259acddca767012a7ebe87168a36a9068414f5f649ad925ebda0035ab6d21

Alternative Methods of Compliance (AMOCs)
(g) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Los Angeles ACO Branch, FAA, may approve AMOCs 
for this AD. Send your proposal to: Eric Schrieber, Aviation Safety 
Engineer, Los Angeles ACO Branch, Compliance and Airworthiness 
Division, FAA, 3960 Paramount Blvd., Lakewood, California 90712; 
telephone (562) 627-5348; email [email protected].
    (2) For operations conducted under a 14 CFR part 119 operating 
certificate or under 14 CFR part 91, subpart K, we suggest that you 
notify your principal inspector, or lacking a principal inspector, 
the manager of the local flight standards district office or 
certificate holding district office, before operating any aircraft 
complying with this AD through an AMOC.

Exact source excerpt. Text positions 13082–13824, end exclusive, in the original decoded publication. SHA-256: 6e0ac8cd979a4c50a16b21509f49e8d8d2ed3d8b6a26abaa369d4aebb0ce105e

Subject
(h) Subject

    Joint Aircraft Service Component (JASC) Code: 6220, Main Rotor 
Head.

Exact source excerpt. Text positions 13824–13912, end exclusive, in the original decoded publication. SHA-256: 2e0b8fd840b132971c9de87308af49116c05d53438943361b52e00beef692de2

Material Incorporated by Reference
(i) Material Incorporated by Reference

    (1) The Director of the Federal Register approved the 
incorporation by reference of the service information listed in this 
paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.
    (2) You must use this service information as applicable to do 
the actions required by this AD, unless the AD specifies otherwise.
    (i) MD Helicopters Service Bulletin SB900-125, dated February 
19, 2016.
    (ii) Reserved.
    (3) For MD Helicopters service information identified in this 
AD, contact 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 http://www.mdhelicopters.com.
    (4) You may view this service information at FAA, Office of the 
Regional Counsel, Southwest Region, 10101 Hillwood Pkwy, Room 6N-
321, Fort Worth, TX 76177. For information on the availability of 
this material at the FAA, call (817) 222-5110.
    (5) You may view this service information that is incorporated 
by reference 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: http://www.archives.gov/federal-register/cfr/ibr-locations.html.

Exact source excerpt. Text positions 13912–15189, end exclusive, in the original decoded publication. SHA-256: 5c29975bd8a8d9b3841db5046ec3fd8af694899014e0f0fa5a68f3a18b7c888f

Explicit historical replacement wording

Find all recorded historical references to AD 2017-17-03 · 0 printed reference observations in this pinned collection.

These are observations from one dated publication. Current legal status is unknown; aircraft applicability, installed configuration, compliance and burden require separate evidence. Missing or unparsed conditions remain unknown.

Why these observations are shown

They were extracted offline from the same immutable official HTML source as the complete recorded text. The dated source wording, original text coordinates and exact quote digests are retained. PDF/text agreement and current regulatory effect have not been qualified.

Observation revision: whole-ad-publication-clause-observations-1.0.1. Text SHA-256: 3a29c4e24fa5d6ee8a69e44b05b4d48f9c26f6a9f1093d360c956f9ca2bd24d8. Source manifest: e4c772c57e6efd95b10ff9c801a3c5ebdb34955e9d10137e9b8cc99fafa2540d.

Official source · 2017-08-21

Publication text

This is the complete recorded text of this dated publication.

Current legal effect is unknown. Aircraft applicability, installed configuration and compliance require separate evidence. PDF/text agreement has not been evaluated.

Read the complete official publication text
[Federal Register Volume 82, Number 160 (Monday, August 21, 2017)]
[Rules and Regulations]
[Pages 39523-39525]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2017-17085]


-----------------------------------------------------------------------

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2017-0270; Product Identifier 2016-SW-032-AD; Amendment 
39-18993; AD 2017-17-03]
RIN 2120-AA64


Airworthiness Directives; MD Helicopters, Inc., Helicopters

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

-----------------------------------------------------------------------

SUMMARY: We are superseding Airworthiness Directive (AD) 2014-16-01 for 
MD Helicopters, Inc. (MDHI), Model MD900 helicopters. AD 2014-16-01 
required an eddy current inspection of the main rotor upper hub 
assembly (upper hub) for a crack. This AD requires additional 
inspections and replacing the fillet seal. This AD was prompted by 
three additional reports of upper hub cracks. The actions of this AD 
are intended to prevent an unsafe condition on these products.

DATES: This AD is effective September 25, 2017.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of September 
25, 2017.

ADDRESSES: For service information identified in this final rule, 
contact 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 http://www.mdhelicopters.com. You may 
review the referenced service information at the FAA, Office of the 
Regional Counsel, Southwest Region, 10101 Hillwood Pkwy, Room 6N-321, 
Fort Worth, TX 76177. It is also available on the Internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2017-
0270.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://www.regulations.gov in Docket No. FAA-2017-0270; or in person at the 
Docket Management Facility between 9 a.m. and 5 p.m., Monday through 
Friday, except Federal holidays. The AD docket contains this AD, any 
incorporated-by-reference information, the economic evaluation, any 
comments received, and other information. The address for the Docket 
Office (phone: 800-647-5527) is Document Management Facility, U.S. 
Department of Transportation, Docket Operations, M-30, West Building 
Ground Floor, Room W12-140, 1200 New Jersey Avenue SE., Washington, DC 
20590.

FOR FURTHER INFORMATION CONTACT: Eric Schrieber, Aviation Safety 
Engineer, Los Angeles ACO Branch, Compliance and Airworthiness 
Division, FAA, 3960 Paramount Blvd., Lakewood, California 90712; 
telephone (562) 627-5348; email [email protected].

SUPPLEMENTARY INFORMATION: 

Discussion

    We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR 
part 39 to remove AD 2014-16-01, Amendment 39-17925 (79 FR 45322, 
August 5, 2014) and add a new AD. AD 2014-16-01 applied to MDHI Model 
MD900 helicopters, serial numbers 900-00008 through 900-00140, with an 
upper hub part number (P/N) 900R2101006-105, -107, -109, or -111 
installed. AD 2014-16-01 required eddy current inspecting the upper hub 
and replacing it if there is a crack. The NPRM published in the Federal 
Register on April 3, 2017 (82 FR 16138).
    The NPRM was prompted by reports of three additional cracks found 
in the MD900 fleet. These cracks were not discovered by the one-time 
eddy current inspection required by AD 2014-16-01, but were found 
during regular maintenance of the upper hub. The NPRM proposed to 
require for MDHI

[[Page 39524]]

MD900 helicopters with an upper hub, regardless of helicopter serial 
number, repetitive visual inspections of the fillet seal and the areas 
around the flexbeam boltholes for a crack and repetitive visual 
inspections of the lead leg shims and bushings for corrosion around the 
flexbeam boltholes. The NPRM also proposed repetitive ultrasonic eddy-
current inspections of the areas adjacent to the flexbeam boltholes for 
a crack. If during any inspection there is corrosion or a crack, the 
NPRM proposed replacing the upper hub before further flight. Finally, 
after each inspection, the NPRM proposed installing a fillet seal to 
the bushing and upper hub interface.

Comments

    We gave the public the opportunity to participate in developing 
this AD, but we did not receive any comments on the NPRM.

FAA's Determination

    We have reviewed the relevant information and determined that an 
unsafe condition exists and is likely to exist or develop on other 
helicopters of the same type design and that air safety and the public 
interest require adopting the AD requirements as proposed.

Related Service Information Under 1 CFR Part 51

    MDHI has issued Service Bulletin SB900-125, dated February 19, 
2016, which describes procedures for repetitive visual and eddy current 
inspections of the upper hub upper and lower flexbeam bolthole areas 
and for applying a fillet seal on the interface of the bushing and the 
flex beam retention bolt hole.
    This service information is reasonably available because the 
interested parties have access to it through their normal course of 
business or by the means identified in the ADDRESSES section.

Differences Between This AD and the Service Information

    The service information applies to upper hubs with 1,000 or more 
hours TIS. This AD applies to all upper hubs regardless of hours TIS. 
The service information applies to upper hub P/N 900R2101006-107 and -
109; this AD also applies to upper hub P/N 900R2101006-105 and -111.

Costs of Compliance

    We estimate that this AD affects 23 helicopters of U.S. Registry. 
At an average labor rate of $85 per hour, we estimate that operators 
may incur the following costs in order to comply with this AD.
    Inspecting the fillet seal around the flexbeam boltholes (100 hour 
TIS inspection) requires about 1 work-hour, for a cost per helicopter 
of $85 and a cost of $1,955 for the fleet, per inspection cycle. 
Inspecting the flexbeam area and lead leg shims and bushings (annual 
inspection) requires about 2 work-hours, for a cost per helicopter of 
$170 and a cost of $3,910 for the fleet, per inspection cycle. Eddy 
current inspecting (1,000 hour TIS inspection) the upper hub requires 
about 2 work-hours, for a cost per helicopter of $170 and a cost of 
$3,910 for the fleet.
    If required, replacing the upper hub requires about 11 work-hours, 
and required parts would cost about $15,998, for a cost per helicopter 
of $16,933. If required, replacing a missing or damaged fillet seal 
requires about .5 work-hour, and required parts cost would be minimal, 
for a cost per helicopter of $43.

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.

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 this AD:
    (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),
    (3) Will not affect intrastate aviation in Alaska to the extent 
that a regulatory distinction is required, and
    (4) 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.

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 FAA amends 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 Airworthiness Directive (AD) 
2014-16-01, Amendment 39-17925 (79 FR 45322, August 5, 2014), and 
adding the following new AD:

2017-17-03 MD Helicopters, Inc. (MDHI): Amendment 39-18993; Docket 
No. FAA-2017-0270; Product Identifier 2016-SW-032-AD.

(a) Applicability

    This AD applies to Model MD900 helicopters with main rotor upper 
hub assembly (upper hub) part number 900R2101006-105, -107, -109, or 
-111 installed, certificated in any category.

(b) Unsafe Condition

    This AD defines the unsafe condition as a cracked upper hub. 
This condition could result in failure of the upper hub and 
subsequent loss of control of the helicopter.

(c) Affected ADs

    This AD supersedes AD 2014-16-01, Amendment 39-17925 (79 FR 
45322, August 5, 2014).

(d) Effective Date

    This AD becomes effective September 25, 2017.

(e) Compliance

    You are responsible for performing each action required by this 
AD within the specified compliance time unless it has already been 
accomplished prior to that time.

(f) Required Actions

    (1) Within 100 hours time-in-service (TIS), and thereafter at 
intervals not to exceed 100 hours TIS:
    (i) Inspect the fillet seal around each flexbeam bolthole to 
determine whether it adheres properly to the hub or bushing or is 
missing. Indications of an improperly

[[Page 39525]]

adhered seal include lifting, bubbling, peeling away, drying out, or 
cracking. If the fillet seal is not properly adhered or is missing, 
before further flight, replace the fillet seal with sealant C232 or 
equivalent by following the Accomplishment Instructions, paragraphs 
2.D.(2) through 2.D.(5) and Figure 1, of MD Helicopters Service 
Bulletin SB900-125, dated February 19, 2016 (SB900-125).
    (ii) Using a light and a 10X or higher power magnifying glass, 
inspect the area outside of the fillet seal around each flexbeam 
bolthole on the top of the upper hub assembly for a crack. If there 
is a crack, before further flight, replace the upper hub assembly.
    (2) Within 12 months, and thereafter at intervals not to exceed 
12 months:
    (i) Remove the paint and primer from the area around each 
flexbeam bolthole on top of the upper hub. Remove the fillet seal 
from the mating surface of each bushing and the top of the upper 
hub.
    (ii) Using a light and a 10X or higher power magnifying glass, 
inspect the area around each flexbeam bolthole for a crack. If there 
is a crack, before further flight, replace the upper hub assembly.
    (iii) Inspect each lead leg shim and bushing for corrosion 
around the flexbeam boltholes on the bottom of the upper hub in the 
flexbeam pockets. If there is corrosion, before further flight:
    (A) Remove the lead leg shim from the flexbeam pocket and clean 
the area adjacent to the flexbeam bolthole to remove any corrosion 
within maximum repair damage limits. If the corrosion exceeds 
maximum repair damage limits, replace the upper hub assembly.
    (B) Using a light and a 10X or higher power magnifying glass, 
inspect the area around the flexbeam bolthole for a crack. If there 
is a crack, before further flight, replace the upper hub assembly.
    (iv) Replace the fillet seal as described in paragraph (f)(1)(i) 
of this AD.
    (3) Within 1,000 hours TIS, and thereafter at intervals not to 
exceed 1,000 hours TIS:
    (i) Eddy current inspect the areas adjacent to each flexbeam 
bolthole, top and bottom, for a crack. This eddy current inspection 
must be performed by a Level II or higher technician with the 
American Society for Nondestructive Testing ASNT-TC-1A, European 
Committee for Standardization CEN EN 4179, Military Standard MIL-
STD-410, National Aerospace Standard NAS410, or equivalent 
certification who has performed an eddy current inspection within 
the last 12 months. If there is a crack, before further flight, 
replace the upper hub assembly.
    (ii) Replace the fillet seal as described in paragraph (f)(1)(i) 
of this AD.

(g) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Los Angeles ACO Branch, FAA, may approve AMOCs 
for this AD. Send your proposal to: Eric Schrieber, Aviation Safety 
Engineer, Los Angeles ACO Branch, Compliance and Airworthiness 
Division, FAA, 3960 Paramount Blvd., Lakewood, California 90712; 
telephone (562) 627-5348; email [email protected].
    (2) For operations conducted under a 14 CFR part 119 operating 
certificate or under 14 CFR part 91, subpart K, we suggest that you 
notify your principal inspector, or lacking a principal inspector, 
the manager of the local flight standards district office or 
certificate holding district office, before operating any aircraft 
complying with this AD through an AMOC.

(h) Subject

    Joint Aircraft Service Component (JASC) Code: 6220, Main Rotor 
Head.

(i) Material Incorporated by Reference

    (1) The Director of the Federal Register approved the 
incorporation by reference of the service information listed in this 
paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.
    (2) You must use this service information as applicable to do 
the actions required by this AD, unless the AD specifies otherwise.
    (i) MD Helicopters Service Bulletin SB900-125, dated February 
19, 2016.
    (ii) Reserved.
    (3) For MD Helicopters service information identified in this 
AD, contact 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 http://www.mdhelicopters.com.
    (4) You may view this service information at FAA, Office of the 
Regional Counsel, Southwest Region, 10101 Hillwood Pkwy, Room 6N-
321, Fort Worth, TX 76177. For information on the availability of 
this material at the FAA, call (817) 222-5110.
    (5) You may view this service information that is incorporated 
by reference 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: http://www.archives.gov/federal-register/cfr/ibr-locations.html.

    Issued in Fort Worth, Texas, on August 7, 2017.
Scott A. Horn,
Deputy Director for Regulatory Operations, Compliance & Airworthiness 
Division, Aircraft Certification Service.
[FR Doc. 2017-17085 Filed 8-18-17; 8:45 am]
 BILLING CODE 4910-13-P


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