AD 2000-11-14
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Pilatus Aircraft Limited | PC-12 | Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12 and PC-12/45 Airplanes |
| aircraft | Pilatus Aircraft Limited | PC-12/45 | Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12 and PC-12/45 Airplanes |
Unsafe Condition
Failure to activate airframe pneumatic deicing boots in icing conditions can lead to reduced controllability due to adverse aerodynamic effects of ice adhering to the airplane prior to the first deicing cycle.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Revise the Airplane Flight Manual (AFM) to include requirements for activation of the airframe pneumatic deicing boots. Ensure flightcrews activate the boots at the first signs of ice accumulation.
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
Pilatus Aircraft Ltd. Models PC-12 and PC-12/45 equipped with pneumatic deicing boots.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
This document adopts a new airworthiness directive (AD) that applies to all Pilatus Aircraft Ltd. (Pilatus) Models PC-12 and PC-12/ 45 airplanes that are equipped with pneumatic deicing boots. This AD requires you to revise the Airplane Flight Manual (AFM) to include requirements for activation of the airframe pneumatic deicing boots. This AD is the result of reports of in-flight incidents and an accident (on airplanes other than the affected Pilatus airplanes) that occurred in icing conditions where the airframe pneumatic deicing boots were not activated. The Pilatus Models PC-12 and PC-12/45 airplanes have a similar type design (as it relates to airframe pneumatic ice boots) to the incident and accident airplanes. The actions specified by this AD are intended to assure that flightcrews activate the pneumatic wing and tail deicing boots at the first signs of ice accumulation. This action will prevent reduced controllability of the aircraft due to adverse aerodynamic effects of ice adhering to the airplane prior to the first deicing cycle.
Document Text
Show stored source text (verify against official source)
[Federal Register Volume 65, Number 107 (Friday, June 2, 2000)]
[Rules and Regulations]
[Pages 35270-35272]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 00-13874]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 99-CE-36-AD; Amendment 39-11762; AD 2000-11-14]
RIN 2120-AA64
Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12 and
PC-12/45 Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Final rule.
-----------------------------------------------------------------------
SUMMARY: This document adopts a new airworthiness directive (AD) that
applies to all Pilatus Aircraft Ltd. (Pilatus) Models PC-12 and PC-12/
45 airplanes that are equipped with pneumatic deicing boots. This AD
requires you to revise the Airplane Flight Manual (AFM) to include
requirements for activation of the airframe pneumatic deicing boots.
This AD is the result of reports of in-flight incidents and an accident
(on airplanes other than the affected Pilatus airplanes) that occurred
in icing conditions where the airframe pneumatic deicing boots were not
activated. The Pilatus Models PC-12 and PC-12/45 airplanes have a
similar type design (as it relates to airframe pneumatic ice boots) to
the incident and accident airplanes. The actions specified by this AD
are intended to assure that flightcrews activate the pneumatic wing and
tail deicing boots at the first signs of ice accumulation. This action
will prevent reduced controllability of the aircraft due to adverse
aerodynamic effects of ice adhering to the airplane prior to the first
deicing cycle.
EFFECTIVE DATE: July 17, 2000.
ADDRESSES: You may examine information related to this AD at the
Federal Aviation Administration (FAA), Central Region, Office of the
Regional Counsel, Attention: Rules Docket No. 99-CE-36-AD, 901 Locust,
Room 506, Kansas City, Missouri 64106.
FOR FURTHER INFORMATION CONTACT: Mr. John P. Dow, Sr., Aerospace
Engineer, FAA, Small Airplane Directorate, 901 Locust, Room 506, Kansas
City, Missouri 64106; telephone: (816) 329-4121; facsimile: (816) 329-
4090.
SUPPLEMENTARY INFORMATION:
Events Leading to the Issuance of This AD
What Caused This AD?
This AD is the result of reports of in-flight incidents and an
accident (on airplanes other than the affected Pilatus airplanes) that
occurred in icing conditions where the airframe pneumatic deicing boots
were not activated. The Pilatus Models PC-12 and PC-12/45 airplanes
have a similar type design (as it relates to airframe pneumatic ice
boots) to the incident and accident airplanes.
What Is the Potential Impact If FAA Took No Action?
The information necessary to activate the pneumatic wing and tail
deicing boots at the first signs of ice accumulation is critical for
flight in icing conditions. If we did not take action to include this
information, flight crews could experience reduced controllability of
the aircraft due to adverse aerodynamic effects of ice adhering to the
airplane prior to the first deicing cycle.
Has FAA Taken Any Action to This Point?
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
Pilatus Models PC-12 and PC-12/45 airplanes that are equipped with
pneumatic deicing boots. This proposal published in the Federal
Register as a notice of proposed rulemaking (NPRM) on October 8, 1999
(64 FR 54833). The NPRM proposed to require revising the Limitations
Section of the AFM to include requirements for activation of pneumatic
deicing boots at the first indication of ice accumulation on the
airplane.
Was the Public Invited To Comment?
The FAA invited interested persons to participate in the making of
this amendment. Following is a summary of the two comments received
with FAA's response.
Comment Issue No. 1: Allow the Use of Recent Airplane Flight Manual
(AFM) Additions
What Is the Commenter's Concern?
Pilatus requests that FAA allow the operators of the affected
airplanes to use as an alternative method of compliance the most recent
information for Section 2, Limitations, of the Pilatus PC12 Airplane
Flight Manual (AFM). This information is included in Report No.: 01973-
001, page 2-12, Revision 9: September 1, 1999, and includes the
following language:
The wing and tail leading edge pneumatic deicing boot system
must be activated at the first sign of ice formation anywhere on the
aircraft, or upon annunciation from an ice detector system (if
installed), whichever occurs first.
The wing and tail leading edge pneumatic deicing boot system may
be deactivated only after leaving icing conditions and after the
aircraft is determined to be clear of ice.
What Is FAA's Response to the Concern?
We have determined that inserting this report into the Section 2,
Limitations, of the Pilatus PC12 AFM provides an equivalent level of
safety to the actions included in the NPRM. Therefore, we are changing
the AD to include the option of incorporating into the AFM the
information proposed in the NPRM or Report No.: 01973-001, page 2-12,
Revision 9: September 1, 1999.
Comment Issue No. 2: Information is Already Included in the Normal
Procedures Section of the AFM
What Are the Commenter's Concerns?
The Federal Office for Civil Aviation (FOCA), which is the
airworthiness authority for Switzerland, believes that the intent of
this AD is already covered in the Pilatus PC12 AFM. The FOCA's concerns
are as follows:
1. The appropriate time to activate the pneumatic deice boots on
the affected Pilatus airplanes is prior to entry into icing conditions,
and until the airfoils are free of ice after exiting icing conditions.
This information is included in Section 4.10 (Normal Procedures) of the
PC12 AFM;
2. These instructions are not necessary in the Limitations Section
of the AFM. The Limitations Section should only include limitations
relating to speeds, environment (temperatures),
[[Page 35271]]
or system functions (time limits or configurations). Guidance for this
is in FAA Advisory Circular (AC) 25.1419-1, dated August 18, 1999.
Paragraph 12(b)(2) of this AC identifies the Procedures Section as the
proper place for information ``. . . when the ice protection system
should be activated.''
The FOCA requests FAA withdraw the NPRM.
What Is FAA's Response to the Concerns?
We concur that the information is currently in the Normal
Procedures section of the Pilatus PC12 AFM and that previous guidance
(advisory circulars) provides information for putting this information
in such a section. However, section 91.9 of the Federal Aviation
Regulations (14 CFR 91.9) only mandates the operating limitations
(Limitations Section): ``no person may operate a civil aircraft without
complying with the operating limitations specified in the approved
Airplane or Rotorcraft Flight Manual.''
Based upon the importance of operating the deice boots at the
appropriate time, we determined that the information is mandatory. The
only method FAA has of changing the Limitations Section of an AFM is
through AD action, provided an unsafe condition is demonstrated.
Therefore, we do not concur that the NPRM should be withdrawn. We
are not changing the AD as a result of this comment.
The FAA's Determination
What Is FAA's Final Determination on This Issue?
After careful review of all available information related to the
subject presented above, we have determined that air safety and the
public interest require the adoption of the rule as proposed except for
the following:
--Including the option of incorporating Report No.: 01973-001, page 2-
12, Revision 9: September 1, 1999, into Section 2, Limitations, of the
Pilatus PC12 AFM; and
--Minor editorial corrections.
How Does Including This Option and the Minor Editorial Corrections
Affect the AD?
We have determined that including the AFM option and the minor
corrections will not change the meaning of the AD and will not add any
additional burden upon the public than was already proposed.
Cost Impact
How Many Airplanes Does This AD Impact?
We estimate that this AD affects 100 airplanes in the U.S.
registry.
What Is the Cost Impact of the Affected Airplanes on the U.S. Register?
There is no dollar cost impact. We estimate 1 workhour for you to
insert the AFM revision. You can accomplish this action if you hold at
least a private pilot certificate as authorized by section 43.7 of the
Federal Aviation Regulations (14 CFR 43.7). You must make an entry into
the aircraft records that shows compliance with this AD, in accordance
with section 43.9 of the Federal Aviation Regulations (14 CFR 43.9).
Therefore, the only cost impact of this AD is the time it will take you
to insert the information into the AFM.
Regulatory Impact
The regulations adopted herein 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. Therefore, it
is determined that this final rule does not have federalism
implications under Executive Order 13132.
For the reasons discussed above, I certify that this action (1) is
not a ``significant regulatory action'' under Executive Order 12866;
(2) is not a ``significant rule'' under DOT Regulatory Policies and
Procedures (44 FR 11034, February 26, 1979); and (3) will not have a
significant economic impact, positive or negative, on a substantial
number of small entities under the criteria of the Regulatory
Flexibility Act. A copy of the final evaluation prepared for this
action is contained in the Rules Docket. A copy of it may be obtained
by contacting the Rules Docket at the location provided under the
caption ADDRESSES.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, 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
1. The authority citation for part 39 continues to read as follows:
Authority: 49 U.S.C. 106(g), 40113, 44701.
Sec. 39.13 [Amended]
2. FAA amends Section 39.13 is amended by adding a new
airworthiness directive (AD) to read as follows:
2000-11-14 PILATUS AIRCRAFT LTD.: Amendment 39-11762; Docket No.
99-CE-36-AD.
(a) What airplanes are affected by this AD? Models PC-12 and PC-
12/45 airplanes, all serial numbers, that are:
(1) equipped with pneumatic deicing boots; and
(2) certificated in any category.
(b) Who must comply with this AD? Anyone who wishes to operate
any of the above airplanes on the U.S. Register. The AD does not
apply to your airplane if it is not equipped with pneumatic de-icing
boots.
(c) What problem does this AD address? The information necessary
to activate the pneumatic wing and tail deicing boots at the first
signs of ice accumulation is critical for flight in icing
conditions. If we did not take action to include this information,
flight crews could experience reduced controllability of the
aircraft due to adverse aerodynamic effects of ice adhering to the
airplane prior to the first deicing cycle.
(d) What must I do to address this problem? To address this
problem, you must revise the Limitations Section of FAA-approved
Airplane Flight Manual (AFM) to include the following requirements
for activation of the ice protection systems. You must accomplish
this action within the next 10 calendar days after July 17, 2000
(the effective date of this AD), unless already accomplished. You
may insert a copy of this AD in the AFM to accomplish this action:
<bullet> Except for certain phases of flight where the AFM
specifies that deicing boots should not be used (e.g., take-off,
final approach, and landing), compliance with the following is
required.
<bullet> Wing and Tail Leading Edge Pneumatic Deicing Boot
System, if installed, must be activated:
--At the first sign of ice formation anywhere on the aircraft, or
upon annunciation from an ice detector system, whichever occurs
first; and
--The system must either be continued to be operated in the
automatic cycling mode, if available; or the system must be manually
cycled as needed to minimize the ice accretions on the airframe.
<bullet> The wing and tail leading edge pneumatic deicing boot
system may be deactivated only after:
--Leaving known or observed/detected icing that the flight crew has
visually observed on the aircraft or was identified by the on-board
sensors; and
--After the airplane is determined to be clear of ice.
Note: The FAA recommends periodic treatment of deicing boots
with approved ice release agents, such as ICEX<INF>TM</INF>, in
accordance with the manufacturer's application instructions.
(e) Have I accomplished the intent of this AD if I have
incorporated the latest Pilatus PC12 AFM report into Section 2,
Limitations?
[[Page 35272]]
As an alternative method of compliance to the actions required by
paragraphs (a), (a)(1), and (a)(2) of this AD, you may incorporate
Report No.: 01973-001, page 2-12, Revision 9: September 1, 1999,
into Section 2, Limitations, of the Pilatus PC12 AFM.
(f) Can the pilot accomplish the action? Anyone who holds at
least a private pilot certificate, as authorized by section 43.7 of
the Federal Aviation Regulations (14 CFR 43.7), may incorporate the
AFM revisions required by this AD. You must make an entry into the
aircraft records, showing compliance with this AD, in accordance
with section 43.9 of the Federal Aviation Regulations (14 CFR 43.9).
(g) Can I comply with this AD in any other way? You may use an
alternative method of compliance or adjust the compliance time if:
(1) Your alternative method of compliance provides an equivalent
level of safety; and
(2) The Manager, Small Airplane Directorate, approves your
alternative. Submit your request through an FAA Principal
Maintenance Inspector, who may add comments and then send it to the
Manager.
Note: This AD applies to each airplane identified in paragraph
(a) of this AD, regardless of whether it has been modified, altered,
or repaired in the area subject to the requirements of this AD. For
airplanes that have been modified, altered, or repaired so that the
performance of the requirements of this AD is affected, the owner/
operator must request approval for an alternative method of
compliance in accordance with paragraph (g) of this AD. The request
should include an assessment of the effect of the modification,
alteration, or repair on the unsafe condition addressed by this AD;
and, if you have not eliminated the unsafe condition, specific
actions you propose to address it.
(h) Where can I get information about any already-approved
alternative methods of compliance? Contact the Small Airplane
Directorate, 901 Locust, Room 301, Kansas City, Missouri 64106;
telephone: (816) 329-4121; facsimile: (816) 329-4091.
(i) What if I need to fly the airplane to another location to
comply with this AD? The FAA can issue a special flight permit under
sections 21.197 and 21.199 of the Federal Aviation Regulations (14
CFR 21.197 and 21.199) to operate your airplane to a location where
you can accomplish the requirements of this AD.
(j) When does this amendment become effective? This amendment
becomes effective on July 17, 2000.
Issued in Kansas City, Missouri, on May 24, 2000.
James E. Jackson,
Acting Manager, Small Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 00-13874 Filed 6-1-00; 8:45 am]
BILLING CODE 4910-13-U
Source: Official FAA Source ↗
Retrieved: Apr 6, 2026
Rights: U.S. Government Public Domain
This site is not affiliated with or endorsed by the FAA. Always verify with official sources.