AD 2011-12-10

[Federal Register Volume 76, Number 117 (Friday, June 17, 2011)]
[Rules and Regulations]
[Pages 35330-35334]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2011-14246]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2011-0588; Directorate Identifier 2010-SW-074-AD; 
Amendment 39-16717; AD 2011-12-10]
RIN 2120-AA64


Airworthiness Directives; Robinson Helicopter Company Model 
(Robinson) R22, R22 Alpha, R22 Beta, R22 Mariner, R44, and R44 II 
Helicopters

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

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SUMMARY: This amendment supersedes an existing airworthiness directive 
(AD) for the specified Robinson model helicopters that currently 
requires a visual inspection for skin separation along the leading edge 
of blade skin aft of the skin-to-spar bond line on the lower surface of 
each main rotor blade (blade) and in the tip cap area. The existing AD 
also requires a ``tap test'' for detecting a separation or void in both 
bonded areas and repainting any exposed area of the blades. If any 
separation or void is detected, the AD requires, before further flight, 
replacing the blade. Thereafter, before each flight, the existing AD 
also requires checking for any exposed (bare) metal along the skin-to-
spar bond line on the lower surface of each blade near the tip. If any 
bare metal is found, that AD requires an inspection by a qualified 
mechanic. This amendment contains the same requirements but expands the 
applicability to include all serial-numbered model helicopters and 
limits the applicability to specific blade part numbers. This amendment 
also requires a repetitive inspection of the blade and any necessary 
rework. This amendment is prompted by a fatal accident in Israel. We 
have also included responses to comments objecting to the recording 
requirements in the current AD relating to the pilot checks before each 
flight and to comments that the burden of the before-each-flight pilot 
check exceeds the benefit. We have concluded that a check before the 
first flight of each day is sufficient for aviation safety. The actions 
specified by this AD are intended to provide more specific AD actions, 
to relieve the burdens associated with the before-each-flight check by 
changing it to a daily check, to detect blade skin debond, and to 
prevent blade failure and subsequent loss of control of the helicopter.

DATES: Effective July 5, 2011.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of July 5, 2011.
    We must receive comments on this AD by August 16, 2011.

ADDRESSES: Use one of the following addresses to comment on this AD.
     Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.
     Fax: (202) 493-2251.
     Mail: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue, SE., Washington, DC 20590.
     Hand Delivery: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue, SE., Washington, DC 20590, 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 
Robinson Helicopter Company, 2901 Airport Drive, Torrance, CA 90505, 
telephone (310) 539-0508, fax (310) 539-5198, or at http://www.robinsonheli.com/servelib.htm.
    Examining the Docket: You may examine the docket that contains the 
AD, any comments, and other information on the Internet at http://www.regulations.gov, or in person at the Docket Operations office 
between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays. The Docket Operations office (telephone (800) 647-5527) is 
located in Room W12-140 on the ground floor of the West Building at the 
street address stated in the ADDRESSES section. Comments will be 
available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT: Eric D. Schrieber, Aviation Safety 
Engineer, telephone (562) 627-5348, fax (562) 627-5210 (regarding Model 
R22 helicopters), or Fred Guerin, Aviation Safety Engineer, telephone 
(562) 627-5232, fax (562) 627-5210 (regarding Model R44 helicopters).

SUPPLEMENTARY INFORMATION: On December 17, 2007, we issued AD 2007-26-
12, Amendment 39-15314 (73 FR 397, January 3, 2008). That AD requires a 
one-time visual inspection for skin

[[Page 35331]]

separation along the leading edge of the blade skin aft of the skin-to-
spar bond line on the lower surface of each blade and in the tip cap 
area. That AD also requires a ``tap test'' for detecting a separation 
or void in both bonded areas. That AD also requires repainting any 
exposed area of the blades and replacing the blade before further 
flight if any separation or void occurs. Thereafter, the AD requires, 
before each flight, checking for any exposed (bare) metal along the 
skin-to-spar bond line on the lower surface of each blade near the tip. 
If any bare metal is found, a mechanic must visually inspect the area, 
perform a ``tap test,'' remove both blade tip covers, and inspect the 
area. That AD was prompted by 11 reports of blade debond, some 
occurring in flight and some found during routine maintenance. Blades 
that develop a debond at the tip may continue to debond causing failure 
of the blade. This condition most often results from erosion of the 
protective layer of paint that exposes the edge of the skin, which 
allows the skin to erode and eventually peel back. In one of the 
reported incidents, the debond was caused by corrosion from the lower 
surface of the aluminum tip cap, which is bonded to the inside of the 
blade tip. The corrosion caused bubbles under the skin but no peeling 
back of the skin from the spar. The condition was found during 
inspection and not in flight. The condition, if not corrected, could 
result in blade failure and subsequent loss of control of the 
helicopter.
    Since issuing AD 2007-26-12, a fatal accident due to blade 
delamination occurred in Israel. The accident investigation revealed 
that the operator was in possession of both the United States AD and 
the service information but apparently failed to follow the United 
States AD requirements and the service information. However, due to the 
severity of the unsafe condition, we have determined that modification 
of the AD requirements is necessary to further aid in correcting the 
unsafe condition by performing the checks and inspections to prevent 
further fatalities.
    We have reviewed the following Robinson service information:
     Letter titled ``Additional Information Regarding Main 
Rotor Blade Skin Debonding,'' dated May 25, 2007, discussing blade skin 
debonding;
     Rotorcraft Flight Manual (RFM) changes to the Normal 
Procedures Section 4 and Systems Description Section 7, revised April 
20, 2007, for each applicable model helicopter containing a ``caution'' 
about skin-to-spar bond line erosion;
     One Service Letter with two different Nos.: R22 SL-56B and 
R44 SL-32B, revised April 30, 2010, specifying proper inspection and 
protection (refinishing) of bonded areas; and
     Service Bulletins SB-103, dated April 30, 2010, for the 
Model R22, and SB-72, dated April 30, 2010, for the Model R44 
helicopters specifying proper inspection and protection (refinishing) 
of bonded areas for certain affected blades.
    Although not required by this AD, Robinson has developed 
replacement blades, part number C016-7, for the Model R44 helicopter, 
and part number A016-6 for the Model R22 helicopter. The FAA may 
require installing these replacement blades in a future AD.
    Also, since issuing AD 2007-26-12, we have received various 
comments from 32 commenters and have given due consideration to each 
one. We have identified 13 unique issues and addressed those issues as 
follows:
    Twenty-six commenters state that requiring a maintenance logbook 
entry before each flight to document the blade check for the exposed 
skin-to-spar bonded area on the lower surface of each blade is 
unnecessary and burdensome. The commenters also state that the 
requirement does not add to safety, will require keeping the 
maintenance logbook in the aircraft, and will ``visually pollute'' the 
logbook distracting from seeing real maintenance trends.
    Upon reconsideration, we agree that making a logbook entry at each 
preflight check may not be necessary. Therefore, we are replacing the 
``before each flight'' check and maintenance logbook entry with a daily 
``before the first flight of each day'' check and logbook entry. A 
``caution'' to check for paint erosion on the lower surface of the 
blade along the skin-to-spar bond line will be a part of the pre-flight 
check section of the revised FAA-approved RFM. We do not agree that 
maintenance logbook entries ``pollute the logbook'' and distract from 
seeing real maintenance trends. Operators may make the entries on a 
separate maintenance record sheet and keep that record sheet as an 
appendix to the logbook.
    Seventeen commenters state that requiring logbook entries during 
each preflight effectively prohibits student pilots from performing 
these visual checks and restricts them from flying cross-country 
flights.
    We agree that preflight entries into the logbook will prohibit 
student pilots from flying solo cross-country flights. Changing the 
logbook entry requirement from pre-flight to daily will allow the 
student's flight instructor or a mechanic to make the required logbook 
entry before the days cross country activity. This will allow the 
student to fly solo on cross-country flights.
    Six commenters state that either the AD is unclear as to whether a 
pilot or a mechanic should do the checks or that the visual check is 
difficult without a ladder to see the blade closely.
    The FAA agrees that the AD is not specific as to whether a pilot or 
a mechanic may do the daily check. The ``Daily or Preflight Check'' 
section of the FAA-Approved RFM is intended to facilitate the paint 
erosion check by the pilot, and the pilot or a mechanic may perform the 
check before each flight. The FAA does not agree that a ladder is 
required to perform this check. When viewing the blade, the requirement 
is to look at the lower surface of the blade in the area of the bond 
line for missing paint. This detail should be obvious to any one with 
normal vision from several feet away.
    One commenter states that if this issue is due to a manufacturing 
problem, the FAA should mandate that Robinson pay to replace the 
blades.
    We do not believe that this blade debond is due to a manufacturing 
problem. This debond issue appears to be due to the basic design and 
maintenance, and the actions taken in AD 2007-26-12 have been shown to 
detect and to prevent the debond problem. However, reliance on 
continued inspections is an inadequate long term solution. We are 
considering a subsequent AD to terminate the inspection requirement by 
mandating the replacement of these rotor blades.
    One commenter suggests that Robinson send out kits for abrasion 
resistant tape to fix the erosion problem.
    We do not agree that blade tape will resolve the unsafe condition 
even though tape is designed to provide longer resistance to erosion 
than paint. The same unsafe condition exists with both.
    Two commenters state this problem was known for 10 months before 
the AD's release and should not be an immediately adopted rule (IAR). 
Also, the commenters state more information was made available before 
issuing the AD to change the requirements.
    We agree that we were aware of the safety concern even though the 
AD had not been issued. We do not agree that the AD should not have 
been an IAR. As stated in the preamble to the AD, the ``very short time 
intervals'' required by the AD made notice and the opportunity for 
prior public comment impracticable and justified issuing the IAR. The 
AD was issued after considering all known

[[Page 35332]]

information pertaining to the safety concern.
    Two commenters state that the AD applies to helicopter serial 
numbers rather than blade serial numbers, which could result in missed 
initial checks if the blades from helicopters addressed by the AD are 
reinstalled on helicopters not subject to the AD.
    We agree and are revising the ``Applicability'' section to apply to 
certain part-numbered blades instead of certain serial-numbered 
helicopters. This will also result in different part-numbered blades 
not being affected by this AD.
    One commenter states that repainting of the blade is difficult, 
burdensome, expensive, and increases downtime.
    We do not consider repainting of the blade costly relative to the 
safety risk. Inspecting and maintaining the integrity of the spar-to-
blade bond line with paint corrects the unsafe condition that could 
result from erosion of the bond between the spar and the blade skin, 
which could cause failure of the blade.
    Five commenters state the Pilot's Operating Handbook has been 
updated to include the visual inspections outlined in the AD.
    We recognize the preflight check exists in the FAA Approved RFM, 
and we expect pilots and operators to monitor the erosion on the blades 
when they make this check before each flight.
    One commenter states the AD is not applicable to blades that are 
not eroded, and many operators can fly 2,200 hours without exposing the 
bond line. The commenter asks why they are subject to this AD since 
their blades are not eroded.
    We agree that blades that are not eroded will not have this debond 
condition, and if they continue to be noneroded, many operators can fly 
2,200 hours without exposing the bond line. Erosion of the paint is 
dependent upon the amount of erosive particles in the air and varies 
widely from one flight environment to another. Since there is no 
limitation on which environment a helicopter may be operated, checks 
are necessary to maintain an awareness of the condition of the paint at 
the bond line. In addition to the environmental concerns, we have 
determined that some bonded end caps experience corrosion where they 
contact the lower skin, and with both factors at work, checking all 
blades is warranted.
    One commenter states the order of the inspection should be reversed 
to do the inspection immediately and then do a check every 10 to 20 
hours.
    We do not agree that it should be reversed. The 10-hour time before 
the first inspection is common practice to allow for AD action 
implementation if there is an acceptably low risk of failure in those 
10 hours. Additionally, that time is granted to allow enough time for 
remotely located helicopters to fly to an appropriate maintenance base. 
Performing and recording a check before the first flight of each day, 
instead of every 10 to 20 hours, is a better way to allow the pilot to 
monitor any erosion trend that may occur. This way, the operator will 
be aware if the bond line is near exposure and plan accordingly.
    One commenter states the AD requires repainting any exposed bare 
metal on the blade and asks what if the bare metal is elsewhere than 
the bond line.
    We agree that only the exposed area of the bond line needs to be 
painted. The incorporated Robinson Service Bulletin refers to the 
Service Letter that specifies the area of inspection and repaint.
    The Australian Civil Aviation Safety Authority gave an oral comment 
to the FAA that instead of using a 1965 or later U.S. quarter dollar 
coin to perform the tap test, they would like to require alternate 
tools.
    The FAA agrees that an equivalent and appropriate tool other than a 
1965 or later U.S. quarter dollar may be used, and we included in the 
AD a statement that other equivalent and appropriate tools may be used 
for the inspection.
    After careful review of the available data, including the comments 
noted above, the FAA has determined that air safety and the public 
interest require adopting the rule. This AD supersedes AD 2007-26-12 to 
revise the applicability to include all serial-numbered helicopters and 
to limit the applicability to specify part-numbered blades and to 
require the following:
     Before the first flight of each day, visually checking for 
any bare metal skin-to-spar joint area on the lower surface of each 
blade. An owner/operator (pilot) holding at least a private pilot 
certificate may perform this visual check and must enter compliance 
into the aircraft maintenance records in accordance with 14 CFR 43.11 
and 91.417(a)(2)(v).
     If you find any bare metal in the area of the skin-to-spar 
bond line, before further flight, inspecting the blade by following the 
requirements of this AD.
     At specified intervals, inspecting each blade for 
corrosion, a separation, a void, a gap, or a dent.
     Before further flight, refinishing any exposed area of a 
blade.
     Before further flight, replacing any unairworthy blade 
with an airworthy blade.
    Accomplish the actions by following specified portions of the 
service bulletins described previously.
    The short compliance time involved is required because the 
previously described critical unsafe condition can adversely affect the 
controllability and structural integrity of the helicopter. Therefore, 
visually checking for any bare metal is required before further flight, 
and this AD must be issued immediately. The 100-hour inspection is 
required based upon the utilization rate of the helicopters because 
some operators could fly 100 hours within 30 days. 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.
    We estimate that this AD will affect 2,690 helicopters on the U.S. 
registry. We also estimate the following:
     Time to perform the before flight each day is negligible.
     3 work hours to inspect 2 blades and
     10 work hours to replace each unairworthy blade, with an 
estimated 10 blades to be replaced (based on reports of 10 affected 
blades in the past 2 years) at an average labor rate of $85 per work 
hour.
     Required parts will cost about $18,130 for a Model R22 
blade and about $24,800 for a Model R44 blade.

We estimate an average of 7 recurrent annual or 100-hour inspections 
before blade retirement. Based on these figures, we estimate the total 
cost of the AD on U.S. operators to be $5,024,800. This figure includes 
$4,801,650 to inspect all the blades 7 times; plus $94,900 to replace 5 
of the Model R22 blades; plus $128,250 to replace 5 of the Model R44 
blades.

Comments Invited

    This AD is a final rule that involves requirements affecting flight 
safety, and we did not precede it by notice and an opportunity for 
public comment. We invite you to send any written relevant data, views, 
or arguments regarding this AD. Send your comments to an address listed 
under the ADDRESSES section. Include the docket number ``FAA-2011-0588; 
Directorate Identifier 2010-SW-074-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.

[[Page 35333]]

    We will post all comments we receive, without change, to http://www.regulations.gov, including any personal information you provide. We 
will also post a report summarizing each substantive verbal contact we 
receive concerning this AD. Using the search function of the 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).

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 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) 
2007-26-12, Amendment 39-15314 (73 FR 400; January 3, 2008), 
Directorate Identifier 2007-SW-04-AD; and by adding a new AD to read as 
follows:

2011-12-10 Robinson Helicopter Company: Amendment 39-16717; Docket 
No. FAA-2011-0588, Directorate Identifier 2010-SW-074-AD. Supersedes 
AD 2007-26-12, Amendment 39-15314, Docket No. FAA-2007-0378, 
Directorate Identifier 2007-SW-04-AD.

    Applicability: Model R22, R22 Alpha, R22 Beta, and R22 Mariner 
helicopters, with main rotor blade (blade), part number (P/N) A016-
4; and Model R44 and R44 II helicopters, with blade, P/N C016-2 or 
C016-5, certificated in any category.
    Compliance: Required as indicated.
    To detect blade skin debond and prevent blade failure and 
subsequent loss of control of the helicopter, do the following:
    (a) Before the first flight of each day, visually check for any 
exposed (bare metal) skin-to-spar joint area on the lower surface of 
each blade. The actions required by this paragraph may be performed 
by the owner/operator (pilot) holding at least a private pilot 
certificate and must be entered into the aircraft records showing 
compliance with this AD in accordance with 14 CFR 43.9(a)(1)-(4) and 
14 CFR 91.417(a)(2)(v). The record must be maintained as required by 
14 CFR 91.417, 121.380, or 135.439. This authorization is an 
exception to our standard maintenance regulations.
    (b) If you find any bare metal in the area of the skin-to-spar 
bond line, before further flight, inspect the blade by following the 
requirements of paragraph (d) of this AD.
    (c) Within 10 hours time-in-service (TIS), unless done 
previously, and at intervals not to exceed 100 hours TIS or at each 
annual inspection, whichever occurs first, inspect each blade for 
corrosion, a separation, a gap, or a dent by following the 
Compliance Procedure, paragraphs 1 through 6 and 8, of Robinson R22 
Service Bulletin SB-103, dated April 30, 2010 (SB103) for the R22 
series helicopters, and Robinson R44 Service Bulletin SB-72, dated 
April 30, 2010 (SB72), for the R44 series helicopters. Although the 
Robinson service information limits the magnification to 10 x, a 
higher magnification is acceptable for this inspection. Also, an 
appropriate tap test tool which provides similar performance, 
weight, and consistency of tone may be substituted for the ``1965 or 
later United States Quarter-dollar coin,'' which is specified in the 
Compliance Procedure, paragraph 2, of SB-72 and SB-103.
    (d) Before further flight, refinish any exposed area of a blade 
by following the Compliance Procedure, paragraphs 2 through 6, of 
Robinson R22 Service Letter SL-56B and R44 Service letter SL-32B, 
dated April 30, 2010, for both the R22 and R44 series helicopters.
    (e) Before further flight, replace any unairworthy blade with an 
airworthy blade.

    Note: The Robinson letter titled ``Additional Information 
Regarding Main Rotor Blade Skin Debonding,'' dated May 25, 2007, 
which is not incorporated by reference, contains additional 
information about the subject of this AD. This document is available 
at http://www.robinsonheli.com.

    (f) To request a different method of compliance or a different 
compliance time for this AD, follow the procedures in 14 CFR 39.19. 
Send your request to the Manager, Los Angeles Aircraft Certification 
Office, FAA, Airframe Branch, 3960 Paramount Blvd., Lakewood, 
California 90712, regarding Model R22 helicopters ATTN: Eric D. 
Schrieber, Aviation Safety Engineer, telephone (562) 627-5348, fax 
(562) 627-5210, or regarding Model R44 helicopters Attn: Fred 
Guerin, Aviation Safety Engineer, telephone (562) 627-5232, fax 
(562) 627-5210.
    (g) Special flight permits will not be issued.
    (h) The Joint Aircraft System/Component (JASC) Code is: 6210 
Main Rotor Blades.
    (i) The inspections shall be done following the specified 
portions of Robinson R22 Service Bulletin SB-103, dated April 30, 
2010, or R44 Service Bulletin SB-72, dated April 30, 2010, as 
appropriate for each model helicopter. Repaint the exposed area of a 
blade by following Robinson R22 Service letter SL-56B and R44 
Service Letter SL-32B (combined in one document), dated April 30, 
2010. 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 Robinson Helicopter 
Company, 2901 Airport Drive, Torrance, CA 90505, telephone (310) 
539-0508, fax (310) 539-5198, or at http://www.robinsonheli.com/servelib.htm. Copies may be inspected at the FAA, Office of the 
Regional Counsel, Southwest Region, 2601 Meacham Blvd., Room 663, 
Fort Worth, Texas, or 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/code_of_federal_regulations/ibr_locations.html.
    (j) This amendment becomes effective on July 5, 2011.


[[Page 35334]]


    Issued in Fort Worth, Texas, on June 2, 2011.
Kim Smith,
Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 2011-14246 Filed 6-16-11; 8:45 am]
BILLING CODE 4910-13-P