55208 Federal Register / Vol. 64, No. 196 / Tuesday, October 12, 1999 / Proposed Rules

• Wing and Tail Pneumatic DEPARTMENT OF TRANSPORTATION the address specified above. All Deicing Boot System, if installed, must be communications received on or before activated: Federal Aviation Administration the closing date for comments, specified —At the first sign of ice formation above, will be considered before taking anywhere on the , or upon 14 CFR Part 39 action on the proposed rule. The annunciation from an ice detector [Docket No. 99±CE±47±AD] proposals contained in this notice may system, whichever occurs first; and be changed in light of the comments RIN 2120±AA64 —The system must either be continued to received. be operated in the automatic cycling Airworthiness Directives; Comments are specifically invited on mode, if available; or the system must be Technologies of Australia Pty Ltd. the overall regulatory, economic, manually cycled as needed to minimize Models N22B and N24A Airplanes environmental, and energy aspects of the ice accretions on the . the proposed rule. All comments • The wing and tail leading edge AGENCY: Federal Aviation submitted will be available, both before pneumatic deicing boot system may be Administration, DOT. and after the closing date for comments, deactivated only after leaving icing ACTION: Notice of proposed rulemaking in the Rules Docket for examination by conditions and after the airplane is (NPRM). interested persons. A report that determined to be clear of ice.’’ summarizes each FAA-public contact (b) Incorporating the AFM revisions, as SUMMARY: This document proposes to concerned with the substance of this required by this AD, may be performed by adopt a new airworthiness directive proposal will be filed in the Rules the owner/operator holding at least a private (AD) that would apply to all AeroSpace Docket. pilot certificate as authorized by section 43.7 Technologies of Australia Pty Ltd. Commenters wishing the FAA to of the Federal Aviation Regulations (14 CFR (AeroSpace Technologies) Models N22B acknowledge receipt of their comments 43.7), and must be entered into the aircraft and N24A airplanes. The proposed AD submitted in response to this notice records showing compliance with this AD in would require revising the Airplane must submit a self-addressed, stamped accordance with section 43.9 of the Federal Flight Manual (AFM) to include postcard on which the following Aviation Regulations (14 CFR 43.9). requirements for activation of the statement is made: ‘‘Comments to (c) Special flight permits may be issued in airframe pneumatic deicing boots. The Docket No. 99–CE–47–AD.’’ The accordance with sections 21.197 and 21.199 proposed AD is the result of reports of postcard will be date stamped and of the Federal Aviation Regulations (14 CFR in-flight incidents and an accident that returned to the commenter. 21.197 and 21.199) to operate the airplane to occurred in where the a location where the requirements of this AD airframe pneumatic deicing boots were Availability of NPRMs can be accomplished. not activated. The actions specified by Any person may obtain a copy of this (d) An alternative method of compliance or the proposed AD are intended to assure NPRM by submitting a request to the adjustment of the compliance time that that flightcrews activate the pneumatic FAA, Central Region, Office of the provides an equivalent level of safety may be wing and tail deicing boots at the first approved by the Manager, Small Airplane Regional Counsel, Attention: Rules signs of ice accumulation. This action Docket No. 99–CE–47–AD, Room 1558, Directorate, 1201 Walnut, suite 900, Kansas will prevent reduced controllability of City, Missouri 64106. The request shall be 601 E. 12th Street, Kansas City, Missouri the aircraft due to adverse aerodynamic 64106. forwarded through an appropriate FAA effects of ice adhering to the airplane Maintenance Inspector, who may add prior to the first deicing cycle. Discussion comments and then send it to the Manager, DATES: Comments must be received on Small Airplane Directorate. On January 9, 1997, an Empresa or before December 1, 1999. Brazileira de Aeronautica, S.A. Note 2: Information concerning the ADDRESSES: Submit comments in (EMBRAER) Model EMB–120RT series existence of approved alternative methods of triplicate to the Federal Aviation compliance with this AD, if any, may be airplane was involved in an Administration (FAA), Central Region, uncommanded roll excursion and obtained from the Small Airplane Office of the Regional Counsel, Directorate. consequent rapid descent that resulted Attention: Rules Docket No. 99–CE–47– in an accident near Monroe, Michigan. (e) Information related to this AD may be AD, Room 1558, 601 E. 12th Street, The post-accident investigation examined at the FAA, Central Region, Office Kansas City, Missouri 64106. Comments conducted by the National of the Regional Counsel, Room 1558, 601 E. may be inspected at this location Transportation Safety Board (NTSB) 12th Street, Kansas City, Missouri 64106. between 8 a.m. and 4 p.m., Monday concluded that the airplane had Issued in Kansas City, Missouri, on through Friday, holidays excepted. accumulated a thin, rough layer of ice October 4, 1999. FOR FURTHER INFORMATION CONTACT: Mr. on its lifting surfaces. That Michael Gallagher, John P. Dow, Sr., Aerospace Engineer, accumulation of ice, in combination Manager, Small Airplane Directorate, Aircraft FAA, Small Airplane Directorate, 1201 with the slowing of the airplane to an Certification Service. Walnut, suite 900, Kansas City, Missouri airspeed inappropriate for the icing [FR Doc. 99–26570 Filed 10–8–99; 8:45 am] 64106; telephone: (816) 426–6932; conditions in which the airplane was BILLING CODE 4910±13±P facsimile: (816) 426–2169. flying, resulted in loss of control that SUPPLEMENTARY INFORMATION: was not corrected before the airplane impacted the ground. The NTSB also Comments Invited concluded that the flight crew did not Interested persons are invited to activate the wing and tail pneumatic participate in the making of the deicing boots. An NTSB proposed rule by submitting such recommendation related to this accident written data, views, or arguments as requested that the FAA mandate that they may desire. Communications pneumatic deicing boots be turned on as should identify the Rules Docket soon as the airplane enters icing number and be submitted in triplicate to conditions.

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The FAA has reviewed the icing- Delayed Activation of Pneumatic onset of ice accretion, with ice not shed related incident history of certain Deicing Boots on the initial deicing boot cycle airplanes, and has determined that icing In accordance with manufacturer continuing to increase in thickness and incidents may have occurred because instructions and FAA-approved airplane being shed during subsequent cycles. During the previously discussed pneumatic deicing boots were not flight manual (AFM) procedures, the November 1997 international workshop, activated at the first evidence of ice flightcrews of most airplanes equipped the inability of flightcrews to accurately accretion. As a result, the handling with pneumatic deicing boots delay the gauge wing and control surfaces ice qualities or the controllability of the initial activation of the boots until a accretion thickness before activating the airplane may have been reduced due to certain quantity of ice has accumulated deicing boots was recognized. Also, the accumulated ice. That factor was on the protected surfaces (boots). Some present in the accident discussed increased airplane drag resulting from crews routinely wait for 1⁄4 to 1⁄2 inch of previously and, as such, constitutes an ice accretion was recognized as a ice to accumulate, and at least one potential contributing cause of unsafe condition. airplane type is routinely flown with up 1 inadvertent airspeed loss that Request for Information to 1 ⁄2 inches of ice on the protected characterized most in-flight icing related surfaces before the initial activation of accidents and incidents. Two airframe On October 1, 1998, the FAA sent the deicing boots. letters to certain manufacturers of manufacturers, whose products airplanes certified in accordance with Ice Bridging comprise a substantial percentage of the turbopropeller transport fleet, reported part 25 of the Federal Aviation In the past, concern about ‘‘ice that, because of these concerns they Regulations (14 CFR part 25). The letters bridging’’ on early pneumatic deicing recommend activating the automatic requested certain icing system design boot designs resulted in the common airframe deicing system at first onset of information and operational procedures practice of delaying activation of ice airframe icing. Those manufacturers applicable to their airplanes concerning protection. Ice bridging of pneumatic have received no reports of deicing boot flight during icing conditions. The deicing boots occurred when a thin letters also requested that manufacturers ice bridging events for these airplanes. layer of ice is sufficiently plastic to The FAA considers that ice provide data showing that the aircraft deform to the shape of the inflated has safe operating characteristics with accumulation on protected surfaces due deicing boot tube without being to delayed boot activation constitutes a ice accreted on the protected surfaces fractured and shed during the ensuing potential safety concern. However, the (boots). The manufacturers were asked tube deflation. As the deformed ice FAA recognizes that not all airplanes to provide data using the following hardens and accretes additional ice, the may be equipped with ‘‘modern’’ assumptions: The most adverse ice deicing boot becomes ineffective in deicing boots (as that term is used in accumulation possible during operation shedding the ‘‘sheath’’ of ice. However, this NPRM). The FAA specifically in the icing envelope specified in part ice accumulation resulting from delayed invites the submission of comments and 25, Appendix C of the Federal Aviation activation may pose an unsafe condition other data regarding the effects of this Regulations (14 CFR part 25), and that due to the resultant adverse proposed AD on airplanes equipped recommended procedures for deicing aerodynamic effects on the airplane’s with older pneumatic deicing boots, boot operation were used. Additionally, performance or handling qualities. including arguments for the retention of the manufacturers were asked to In November 1997, the FAA and the existing activation delays for these provide information related to operation National Aeronautics and Space older-style deicing boots. of the during icing conditions, Administration (NASA) co-sponsored and for information related to an international workshop on aircraft Residual Ice appropriate operating speeds for icing deicing boot ice bridging. The objective During the February conference, the operations. of the workshop was to provide an open attendees agreed that the airplane is at No information received, as a result of forum for investigating the existence of risk while the airplane is accreting ice, that request, has caused the FAA to deicing boot bridging and other and that the airplane must be reconsider the previous conclusion that concerns related to activating ice adequately protected to ensure that no an unsafe condition may exist. protection systems at the initial adverse handling and performance detection of inflight icing. Sixty-seven characteristics develop. An additional Public Meeting representatives from airframe and concern discussed at the conference was Subsequent to the collection of those deicing boot manufacturers, various the possibility that early activation of design and operational data, the FAA airlines, the pilot community, NASA, the might degrade held an international conference on the National Transportation Safety the ice shedding effectiveness of the ‘‘Inflight Operations in Icing Board, non-US civil aviation authorities, deicing boots, resulting in increased Conditions’’, in Washington, DC, on and the FAA participated. At the residual ice, i.e., there would be more February 2–4, 1999. The purpose of the workshop no evidence was presented to ice fragments remaining on the deicing conference was to discuss the status of substantiate that aircraft with modern boots than would exist if a more the FAA Icing Plan and other related deicing boot designs experience ice substantial quantity of ice was allowed efforts. Additionally, the conference bridging. The general consensus of the to form before the first ice shedding provided a forum for representatives of workshop participants was that ice cycle. However, the FAA does not industry to express their viewpoints on bridging is not a problem for modern concur. No data has been provided that current information related to activation pneumatic deicing boot designs due to shows that the presence of residual ice of deicing boots, minimum airspeeds, the use of higher air supply pressures, following an earlier activation of the autopilot operation in icing conditions, faster boot inflation and deflation deicing boots is more hazardous than flightcrew information needs, and cycles, and smaller boot chambers. Icing delaying cycling of the boots until the flightcrew training. Certain information wind tunnel and flight testing of these ice accretes to a larger, specific presented at that meeting is discussed in newer design features with automatic thickness. In fact, testing in icing this proposed rule in the following cycling have demonstrated successful conditions has shown that residual ice section. shedding of ice when activated at the remaining on the boots after the initial

VerDate 06-OCT-99 14:22 Oct 08, 1999 Jkt 190000 PO 00000 Frm 00034 Fmt 4702 Sfmt 4702 E:\FR\FM\12OCP1.XXX pfrm04 PsN: 12OCP1 55210 Federal Register / Vol. 64, No. 196 / Tuesday, October 12, 1999 / Proposed Rules boot cycle is removed during of the deicing boots may be The FAA’s Determination subsequent cycles. inappropriate. For example, a deicing The FAA is aware that, based on As reported during the November boot inflation cycle that begins previous procedures provided to 1997 international workshop, immediately before or during the manufacturers of a substantial flightcrews of many airplanes equipped landing flare or the takeoff rotation may with deicing boots, a historical percentage of the turbopropeller cause unexpected loss of lift or other transport fleet have reported satisfactory precedent has been set that permits adverse aerodynamic events. This waiting to activate the deicing in-flight icing operations of their proposed AD explicitly does not products with recommended procedures equipment. In light of this information supersede procedures in the AFM that and based on reports received, the FAA to activate operation of the deicing boots prohibit using deicing boots for certain in the automatic mode at the onset of considers that certain procedures phases of flight (e.g., during take-off, should be included in the Limitations airframe icing. final approach, and landing). Therefore, the FAA considers that the Section of the AFM for all AeroSpace activation of pneumatic wing and tail The FAA specifically invites the Technologies Models N22B and N24A deicing boots at the first signs of ice submission of comments and other data airplanes to require immediate accumulation is warranted. The FAA regarding adverse effects that may occur activation of the ice protection systems specifically invites the submission of during specific phases of flight, when any ice accumulation is detected data to substantiate that operating the including takeoff, final approach, or on the airplane. deicing boots at the first sign of ice landing. Any recommended speed This proposed action is one of a accretions is more hazardous than restrictions or other operational number of proposed AD’s being issued delaying boot activation until a specific procedures that would be necessary in on airplanes that have been determined thickness of ice has accumulated. order to mitigate any adverse to be subject to the same identified aerodynamic effects of deicing boot unsafe conditions. Currently proposed Other Considerations inflation during critical phases of flight AD’s for other airplanes that are The FAA recognizes that there may be should be fully explained and equipped with pneumatic deicing boots some phases of flight during which use documented. address the following airplanes:

Airplane models Docket No.

Industrie Aeronautiche e Meccaniche, Model Piaggio P±180 Airplanes ...... 99±CE±34±AD Pilatus Britten-Norman Ltd., BN±2T Series Airplanes ...... 99±CE±35±AD Pilatus Aircraft Ltd., Models PC±12 and PC±12/45 Airplanes ...... 99±CE±36±AD Partenavia Costruzioni Aeronauticas, S.p.A., Models AP68TP 300 ``Spartacus'' and AP68TP 600 ``Viator'' Airplanes ...... 99±CE±37±AD Mitsubishi Heavy Industries, Ltd., MU±2B Series Airplanes ...... 99±CE±38±AD LET, a.s., Model L±420 Airplanes ...... 99±CE±39±AD British Aerospace, Jetstream Models 3101 and 3201 Airplanes ...... 99±CE±40±AD Harbin Aircraft Manufacturing Corp., Model Y12 IV airplanes ...... 99±CE±41±AD Empresa Brasileira de Aeronautica S.A. (Embraer), Models EMB±110P1 and EMB±110P2 Airplanes ...... 99±CE±42±AD Dornier Luftfahrt GmbH, 228 Series Airplanes ...... 99±CE±43±AD Bombardier Inc., DHC±6 Series Airplanes ...... 99±CE±44±AD The Cessna Aircraft Company, 208 Series Airplanes ...... 99±CE±45±AD Raytheon Aircraft Company, 90, 99, 100, 200, 300, 1900, and 2000 Series Airplanes ...... 99±CE±46±AD Short Brothers & Harland Ltd., Models SC±7 Series 2 and SC±7 Series 3 Airplanes ...... 99±CE±48±AD The New Piper Aircraft, Inc., PA±31 Series Airplanes ...... 99±CE±49±AD SOCATAÐGroupe AEROSPATIALE, Model TBM 700 Airplanes ...... 99±CE±50±AD Twin Commander Aircraft Corporation, 600 Series Airplanes ...... 99±CE±51±AD Fairchild Aircraft Corporation, SA226 and SA227 Series Airplanes ...... 99±CE±52±AD The Cessna Aircraft Company, Models 425 and 441 Airplanes ...... 99±CE±53±AD Cessna Aircraft Company, Models 500, 550, and 560 Airplanes ...... 99±NM±136±AD Sabreliner Corporation, Models 40, 60, 70, and 80 Series Airplanes ...... 99±NM±137±AD Gulfstream Aerospace, Model G±159 Series Airplanes ...... 99±NM±138±AD McDonnell Douglas, Models DC±3 and DC±4 Series Airplanes ...... 99±NM±139±AD Mitsubishi Heavy Industries, Model YS±11 and YS±11A Series Airplanes ...... 99±NM±140±AD Frakes Aviation, Model, G±73 (Mallard) and G±73T Series Airplanes ...... 99±NM±141±AD Lockheed, Models L±14 and L±18 Series Airplanes ...... 99±NM±142±AD Fairchild Models F27 and FH227 Series Airplanes ...... 99±NM±143±AD Aerospatiale Models ATR±42/ATR±72 Series Airplanes ...... 99±NM±144±AD Jetstream, Model BAe ATP Airplanes ...... 99±NM±145±AD Jetstream, Model 4101 Airplanes ...... 99±NM±146±AD British Aerospace Model HS 748 Series Airplanes ...... 99±NM±147±AD Saab, Model SF340A/SAAB 340B/SAAB 2000 Series Airplanes ...... 99±NM±148±AD CASA Model C±212/CN±235 Series Airplanes ...... 99±NM±149±AD Dornier Model 328±100 Series Airplanes ...... 99±NM±150±AD Lockheed Model 1329±23 and 1329±25 (Lockheed Jetstar) Series Airplanes ...... 99±NM±151±AD de Havilland, Model DHC±7/DHC±8 Series Airplanes ...... 99±NM±152±AD Fokker, Model F27 Mark 100/200/300/400/500/600/700/050 Series Airplanes ...... 99±NM±153±AD Short Brothers, Model SD3±30/SD3±60/SD3-SHERPA Series Airplanes ...... 99±NM±154±AD

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Explanation of the Provisions of the location provided under the caption annunciation from an ice detector Proposed AD ADDRESSES. system, whichever occurs first; and —The system must either be continued to Since an unsafe condition has been List of Subjects in 14 CFR Part 39 be operated in the automatic cycling identified that is likely to exist or Air transportation, Aircraft, Aviation mode, if available; or the system must be develop in other AeroSpace safety, Safety. manually cycled as needed to minimize Technologies Models N22B and N24A the ice accretions on the airframe. airplanes of the same type design The Proposed Amendment • The wing and tail leading edge registered in the United States, the FAA Accordingly, pursuant to the pneumatic deicing boot system may be is proposing AD action. The proposed authority delegated to me by the deactivated only after leaving icing conditions and after the airplane is AD would require revising the Administrator, the Federal Aviation determined to be clear of ice.’’ Limitations Section of the AFM to Administration proposes to amend part (b) Incorporating the AFM revisions, as include requirements for activation of 39 of the Federal Aviation Regulations required by this AD, may be performed by pneumatic deicing boots at the first (14 CFR part 39) as follows: the owner/operator holding at least a private indication of ice accumulation on the pilot certificate as authorized by section 43.7 airplane. PART 39ÐAIRWORTHINESS of the Federal Aviation Regulations (14 CFR DIRECTIVES 43.7), and must be entered into the aircraft Cost Impact records showing compliance with this AD in 1. The authority citation for part 39 accordance with section 43.9 of the Federal The FAA estimates that 10 airplanes continues to read as follows: Aviation Regulations (14 CFR 43.9). in the U.S. registry would be affected by Authority: 49 U.S.C. 106(g), 40113, 44701. (c) Special flight permits may be issued in the proposed AD, that it would take accordance with sections 21.197 and 21.199 approximately 1 workhour per airplane § 39.13 [Amended] of the Federal Aviation Regulations (14 CFR to accomplish the proposed AFM 2. Section 39.13 is amended by 21.197 and 21.199) to operate the airplane to revisions. Accomplishing the proposed adding a new airworthiness directive a location where the requirements of this AD AFM revision requirements of this (AD) to read as follows: can be accomplished. NPRM may be performed by the owner/ (d) An alternative method of compliance or Aerospace Technologies of Australia Pty adjustment of the compliance time that operator holding at least a private pilot Ltd.: Docket No. 99–CE–47–AD. provides an equivalent level of safety may be certificate as authorized by section 43.7 Applicability: Models N22B and N24A approved by the Manager, Small Airplane of the Federal Aviation Regulations (14 airplanes, all serial numbers equipped with Directorate, 1201 Walnut, suite 900, Kansas CFR 43.7), and must be entered into the pneumatic deicing boots, certificated in any City, Missouri 64106. The request shall be aircraft records showing compliance category. forwarded through an appropriate FAA with the proposed AD in accordance Note 1: This AD applies to each airplane Maintenance Inspector, who may add with section 43.9 of the Federal identified in the preceding applicability comments and then send it to the Manager, Aviation Regulations (14 CFR 43.9). The provision, regardless of whether it has been Small Airplane Directorate. only cost impact of the proposed AD is modified, altered, or repaired in the area Note 2: Information concerning the the time it would take each owner/ subject to the requirements of this AD. For existence of approved alternative methods of operator of the affected airplanes to airplanes that have been modified, altered, or compliance with this AD, if any, may be repaired so that the performance of the obtained from the Small Airplane insert the information into the AFM. requirements of this AD is affected, the Directorate. Regulatory Impact owner/operator must request approval for an (e) Information related to this AD may be alternative method of compliance in examined at the FAA, Central Region, Office The regulations proposed herein accordance with paragraph (d) of this AD. of the Regional Counsel, Room 1558, 601 E. would not have substantial direct effects The request should include an assessment of 12th Street, Kansas City, Missouri 64106. the effect of the modification, alteration, or on the States, on the relationship Issued in Kansas City, Missouri, on repair on the unsafe condition addressed by between the national government and October 4, 1999. this AD; and, if the unsafe condition has not the States, or on the distribution of been eliminated, the request should include Michael Gallagher, power and responsibilities among the specific proposed actions to address it. Manager, Small Airplane Directorate, Aircraft various levels of government. Therefore, Compliance: Required as indicated in the Certification Service. in accordance with Executive Order body of this AD, unless already [FR Doc. 99–26571 Filed 10–8–99; 8:45 am] 12612, it is determined that this accomplished. BILLING CODE 4910±13±P proposal would not have sufficient To assure that flightcrews activate the wing federalism implications to warrant the and tail pneumatic deicing boots at the first preparation of a Federalism Assessment. signs of ice accumulation on the airplane, DEPARTMENT OF TRANSPORTATION accomplish the following: For the reasons discussed above, I (a) Within 10 days after the effective date Federal Aviation Administration certify that this action (1) is not a of this AD: Revise the Limitations Section of ‘‘significant regulatory action’’ under the FAA-approved Airplane Flight Manual 14 CFR Part 39 Executive Order 12866; (2) is not a (AFM) to include the following requirements ‘‘significant rule’’ under DOT for activation of the ice protection systems. [Docket No. 99±CE±50±AD] Regulatory Policies and Procedures (44 This may be accomplished by inserting a FR 11034, February 26, 1979); and (3) if copy of this AD in the AFM. RIN 2120±AA64 • promulgated, will not have a significant ‘‘ Except for certain phases of flight economic impact, positive or negative, where the AFM specifies that deicing boots Airworthiness Directives; SOCATAÐ should not be used (e.g., take-off, final on a substantial number of small entities Groupe AEROSPATIALE Model TBM approach, and landing), compliance with the 700 Airplanes under the criteria of the Regulatory following is required. Flexibility Act. A copy of the draft • Wing and Tail Leading Edge Pneumatic AGENCY: Federal Aviation regulatory evaluation prepared for this Deicing Boot System, if installed, must be Administration, DOT. action has been placed in the Rules activated: ACTION: Notice of proposed rulemaking Docket. A copy of it may be obtained by —At the first sign of ice formation (NPRM). contacting the Rules Docket at the anywhere on the aircraft, or upon

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