[Federal Register Volume 61, Number 135 (Friday, July 12, 1996)]
[Proposed Rules]
[Pages 36667-36669]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-17740]
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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39
[Docket No. 96-NM-122-AD]
RIN 2120-AA64
Airworthiness Directives; Short Brothers Model SD3-60 SHERPA
Series Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Notice of proposed rulemaking (NPRM).
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SUMMARY: This document proposes the adoption of a new airworthiness
directive (AD) that is applicable to all Short Brothers Model SD3-60
SHERPA series airplanes. This proposal would require revising the
Airplane Flight Manual (AFM) to provide the flight crew with
recognition cues for, and procedures for exiting from, severe icing
conditions, and to limit or prohibit the use of various flight control
devices. This proposal is prompted by results of a review of the
requirements for certification of the airplane in icing conditions, new
information on the icing environment, and icing data provided currently
to the flight crews. The actions specified by the proposed AD are
intended to minimize the potential hazards associated with operating
the airplane in severe icing conditions by providing more clearly
defined procedures and limitations associated with such conditions.
DATES: Comments must be received by August 29, 1996.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-103,
Attention: Rules Docket No. 96-NM-122-AD, 1601 Lind Avenue, SW.,
Renton, Washington 98055-4056. Comments may be inspected at this
location between 9:00 a.m. and 3:00 p.m., Monday through Friday, except
Federal holidays.
This information may be examined at the FAA, Transport Airplane
Directorate, 1601 Lind Avenue, SW., Renton, Washington.
FOR FURTHER INFORMATION CONTACT: Greg Dunn, Aerospace Engineer,
Standardization Branch, ANM-113, FAA, Transport Airplane Directorate,
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (206)
227-2799; fax (206) 227-1149.
SUPPLEMENTARY INFORMATION:
Comments Invited
Interested persons are invited to participate in the making of the
proposed rule by submitting such written data, views, or arguments as
they may desire. Communications shall identify the Rules Docket number
and be submitted in triplicate to the address specified above. All
communications received on or before the closing date for comments,
specified above, will be considered before taking action on the
proposed rule. The proposals contained in this notice may be changed in
light of the comments received.
Comments are specifically invited on the overall regulatory,
economic, environmental, and energy aspects of the proposed rule. All
comments submitted will be available, both before and after the closing
date for comments, in the Rules Docket for examination by interested
persons. A report summarizing each FAA-public contact concerned with
the substance of this proposal will be filed in the Rules Docket.
Commenters wishing the FAA to acknowledge receipt of their comments
submitted in response to this notice must submit a self-addressed,
stamped postcard on which the following statement is made: ``Comments
to Docket Number 96-NM-122-AD.'' The postcard will be date stamped and
returned to the commenter.
Availability of NPRMs
Any person may obtain a copy of this NPRM by submitting a request
to the FAA, Transport Airplane Directorate, ANM-103, Attention: Rules
Docket No. 96-NM-122-AD, 1601 Lind Avenue, SW., Renton, Washington
98055-4056.
Discussion
On April 24, 1996, the FAA issued 18 AD's (see below for a listing
of all 18 AD's) to require revising the FAA-approved Airplane Flight
Manual (AFM) to provide the flight crew with recognition cues for, and
procedures for exiting from, severe icing conditions, and to limit or
prohibit the use of various flight control devices. These AD's were
published in the Federal Register on May 7, 1996:
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Amendment
Manufacturer/airplane model AD No. No. Federal Register citation
----------------------------------------------------------------------------------------------------------------
de Havilland DHC-6 Series...................... 96-09-11 39-9587 61 FR 20616
EMBRAER EMB-110P1/EMB-110P2.................... 96-09-12 39-9588 61 FR 20636
Beech 99/200/1900 Series....................... 96-09-13 39-9589 61 FR 20638
Dornier 228 Series............................. 96-09-14 39-9590 61 FR 20639
Cessna 208/208B................................ 96-09-15 39-9591 61 FR 20641
Fairchild Aircraft SA226/SA227 Series.......... 96-09-16 39-9592 61 FR 20643
Jetstream 3101/3201............................ 96-09-17 39-9593 61 FR 20644
Jetstream BAe ATP.............................. 96-09-18 39-9594 61 FR 20668
Jetstream 4101................................. 96-09-19 39-9595 61 FR 20669
British Aerospace HS 748 Series................ 96-09-20 39-9596 61 FR 20671
Saab SF340A/SAAB 340B/SAAB 2000 Series......... 96-09-21 39-9597 61 FR 20672
CASA C-212/CN-235 Series....................... 96-09-22 39-9598 61 FR 20674
Dornier 328-100 Series......................... 96-09-23 39-9599 61 FR 20676
EMBRAER EMB-120 Series......................... 96-09-24 39-9600 61 FR 20677
de Havilland DHC-7/DHC-8 Series................ 96-09-25 39-9601 61 FR 20679
Fokker F27 Mark 100/200/300/400/500/600/700/050 96-09-26 39-9602 61 FR 20681
Series.
Short Brothers SD3-30/SD3-60/SD3-SHERPA Series. 96-09-27 39-9603 61 FR 20682
Aerospatiale ATR-42/ATR-72 Series.............. 96-09-28 39-9604 61 FR 20646
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Those actions were prompted by results of a review of the
requirements for certification of the airplane in icing conditions, new
information on the icing environment, and icing data provided currently
to the flight crews.
[[Page 36668]]
The requirements of those AD's are intended to minimize the potential
hazards associated with operating the airplane in severe icing
conditions by providing more clearly defined procedures and limitations
associated with such conditions.
Since the issuance of those AD's, the FAA has determined that Short
Brothers Model SD3-60 SHERPA series airplanes were omitted
inadvertently from the list of airplane models subject to the
potentially unsafe condition described previously and addressed in
those AD's.
This airplane model is manufactured in the United Kingdom and is
type certificated for operation in the United States under the
provisions of section 21.29 of the Federal Aviation Regulations (14 CFR
21.29) and the applicable bilateral airworthiness agreement.
Explanation of Requirements of Proposed Rule
Since an unsafe condition has been identified that is likely to
exist or develop on other airplanes of the same type design, the
proposed AD would require revising the AFM to provide the flight crew
with recognition cues for, and procedures for exiting from, severe
icing conditions, and to limit or prohibit the use of various flight
control devices.
Cost Impact
The FAA estimates that 20 airplanes of U.S. registry would be
affected by this proposed AD, that it would take approximately 1 work
hour per airplane to accomplish the proposed actions, and that the
average labor rate is $60 per work hour. Based on these figures, the
cost impact of the proposed AD on U.S. operators is estimated to be
$1,200, or $60 per airplane.
The cost impact figure discussed above is based on assumptions that
no operator has yet accomplished any of the proposed requirements of
this AD action, and that no operator would accomplish those actions in
the future if this AD were not adopted.
In addition, the FAA recognizes that this proposed AD may impose
operational costs. However, those costs are incalculable because the
frequency of occurrence of the specified conditions and the associated
additional flight time are indeterminable. Nevertheless, because of the
severity of the unsafe condition addressed, the FAA has determined that
continued operational safety necessitates the imposition of these
costs.
Regulatory Impact
The regulations proposed herein would not have substantial direct
effects 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, in
accordance with Executive Order 12612, it is determined that this
proposal would not have sufficient federalism implications to warrant
the preparation of a Federalism Assessment.
For the reasons discussed above, I certify that this proposed
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) if promulgated, 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 draft
regulatory 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.
The Proposed Amendment
Accordingly, pursuant to the authority delegated to me by the
Administrator, the Federal Aviation Administration proposes to amend
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. Section 39.13 is amended by adding the following new
airworthiness directive:
Short Brothers, PLC: Docket 96-NM-122-AD.
Applicability: All Model SD3-60 SHERPA series airplanes,
certificated in any category.
Note 1: This AD applies to each airplane identified in the
preceding applicability provision, 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 (b) 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 the unsafe condition has not been
eliminated, the request should include specific proposed actions to
address it.
Compliance: Required as indicated, unless accomplished
previously.
To minimize the potential hazards associated with operating the
airplane in severe icing conditions by providing more clearly
defined procedures and limitations associated with such conditions,
accomplish the following:
(a) Within 30 days after the effective date of this AD,
accomplish the requirements of paragraphs (a)(1) and (a)(2) of this
AD.
Note 2: Operators must initiate action to notify and ensure that
flight crewmembers are apprised of this change.
(1) Revise the FAA-approved Airplane Flight Manual (AFM) by
incorporating the following into the Limitations Section of the AFM.
This may be accomplished by inserting a copy of this AD in the AFM.
``WARNING
Severe icing may result from environmental conditions outside of
those for which the airplane is certificated. Flight in freezing
rain, freezing drizzle, or mixed icing conditions (supercooled
liquid water and ice crystals) may result in ice build-up on
protected surfaces exceeding the capability of the ice protection
system, or may result in ice forming aft of the protected surfaces.
This ice may not be shed using the ice protection systems, and may
seriously degrade the performance and controllability of the
airplane.
During flight, severe icing conditions that exceed
those for which the airplane is certificated shall be determined by
the following visual cues. If one or more of these visual cues
exists, immediately request priority handling from Air Traffic
Control to facilitate a route or an altitude change to exit the
icing conditions.
--Unusually extensive ice accreted on the airframe in areas not
normally observed to collect ice.
--Accumulation of ice on the lower surface of the wing aft of the
protected area.
--Accumulation of ice on the propeller spinner farther aft than
normally observed.
Since the autopilot may mask tactile cues that indicate
adverse changes in handling characteristics, use of the autopilot is
prohibited when any of the visual cues specified above exist, or
when unusual lateral trim requirements or autopilot trim warnings
are encountered while the airplane is in icing conditions.
All icing detection lights must be operative prior to
flight into icing conditions at night. [NOTE: This supersedes any
relief provided by the Master Minimum Equipment List (MMEL).]''
(2) Revise the FAA-approved AFM by incorporating the following
into the Procedures Section of the AFM. This may be accomplished by
inserting a copy of this AD in the AFM.
``THE FOLLOWING WEATHER CONDITIONS MAY BE CONDUCIVE TO SEVERE IN-FLIGHT
ICING:
Visible rain at temperatures below 0 degrees Celsius
ambient air temperature.
[[Page 36669]]
Droplets that splash or splatter on impact at
temperatures below 0 degrees Celsius ambient air temperature.
PROCEDURES FOR EXITING THE SEVERE ICING ENVIRONMENT:
These procedures are applicable to all flight phases from
takeoff to landing. Monitor the ambient air temperature. While
severe icing may form at temperatures as cold as -18 degrees
Celsius, increased vigilance is warranted at temperatures around
freezing with visible moisture present. If the visual cues specified
in the Limitations Section of the AFM for identifying severe icing
conditions are observed, accomplish the following:
Immediately request priority handling from Air Traffic
Control to facilitate a route or an altitude change to exit the
severe icing conditions in order to avoid extended exposure to
flight conditions more severe than those for which the airplane has
been certificated.
Avoid abrupt and excessive maneuvering that may
exacerbate control difficulties.
Do not engage the autopilot.
If the autopilot is engaged, hold the control wheel
firmly and disengage the autopilot.
If an unusual roll response or uncommanded roll control
movement is observed, reduce the angle-of-attack.
Do not extend flaps during extended operation in icing
conditions. Operation with flaps extended can result in a reduced
wing angle-of- attack, with the possibility of ice forming on the
upper surface further aft on the wing than normal, possibly aft of
the protected area.
If the flaps are extended, do not retract them until
the airframe is clear of ice.
Report these weather conditions to Air Traffic
Control.''
(b) An alternative method of compliance or adjustment of the
compliance time that provides an acceptable level of safety may be
used if approved by the Manager, Standardization Branch, ANM-113,
FAA, Transport Airplane Directorate. Operators shall submit their
requests through an appropriate FAA Principal Operations Inspector,
who may add comments and then send it to the Manager,
Standardization Branch, ANM-113.
Note 3: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the Standardization Branch, ANM-113.
(c) Special flight permits may be issued in accordance with
Secs. 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR
21.197 and 21.199) to operate the airplane to a location where the
requirements of this AD can be accomplished.
Issued in Renton, Washington, on July 8, 1996.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 96-17740 Filed 7-11-96; 8:45 am]
BILLING CODE 4910-13-U
