Results
73-13-07: 73-13-07 GRUMMAN AMERICAN AVIATION CORPORATION: Amdt. 39-1669. Applies to all Model AA-1, Model AA-1A, and Model AA-1B airplanes through Serial Numbers AA-1B-0177 certificated in all categories. Compliance required within the next 10 hours time in service or 30 calendar days, whichever comes first, after the effective date of this airworthiness directive. To clearly indicate to the pilot that spins are prohibited in this make and model airplane, and to provide information to assist in preventing conditions that might lead to accidental spin entry, install the new placards as provided by Grumman American Aviation Corporation Service Bulletin No. 138 or by a suitable alternate procedure as approved by the Chief, Engineering and Manufacturing Branch, Great Lakes Region. This Amendment becomes effective June 25, 1973.
2016-12-02: We are adopting a new airworthiness directive (AD) for various aircraft equipped with a BRP-Powertrain GmbH & Co KG (formerly Rotax Aircraft Engines) 912 A series engine. This AD results from mandatory continuing airworthiness information (MCAI) issued by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as a design change of the engine cylinder head temperature sensor without a concurrent revision of the engine model designation, the engine part number, or the cockpit indication to the pilot. We are issuing this AD to require actions to address the unsafe condition on these products.
2016-11-13: We are superseding airworthiness directive (AD) 99-19-33 for BLANIK LIMITED Models L-13 Blanik and L-13 AC Blanik gliders (type certificate previously held by LET Aeronautical Works). This AD results from mandatory continuing airworthiness information (MCAI) issued by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as lack of distinct color marking of the elevator drive. We are issuing this AD to require actions to address the unsafe condition on these products.
71-14-02: 71-14-02 GOODRICH: Amdt. 39-1236. Applies to B. F. Goodrich 26 x 6.6, 14 PR; tubeless, 200 m.p.h. tire, S/N's 0318 AK 0000 through and including 0365 AK 9999. (a) Prior to next flight, visually inspect the tire, particularly on sidewall and shoulders, for bumps, blisters, or peeling. (b) Replace defective tires with tire or tires having S/N's outside of the subject group, or with an equivalent tire approved by the Chief, Engineering & Manufacturing Branch, FAA, Eastern Region. (c) If a tire within the subject group reveals no specified deficiency, it may be used for a maximum of five (5) landings thereafter, provided the tire is inspected prior to each flight in accordance with paragraph (a). Replace tires after five (5) landings in accordance with paragraph (b). This amendment is effective July 2, 1971, and was effective upon receipt for all recipients of the airmail letter, dated May 22, 1971, which contained this amendment.
76-02-02: 76-02-02 SOCIETE NATIONALE INDUSTRIELLE AEROSPATIALE: Amendment 39- 2495. Applies to Model SA341G "Gazelle" helicopters, certificated in all categories, equipped with horizontal transmission shafts P/N's 341A.34.1106.00, .01, .02, or .03, or coupling shafts P/N's 341A.34.1114.00, .01, or .02, or bearing attachment straps P/N 341A.34.1033.00. Compliance is required as indicated, unless already accomplished. To prevent possible failure of tail rotor drive system components and possible loss of control of the helicopter, accomplish the following: (a) Within the next 10 hours' time in service after the effective date of this AD, paint an alignment index line on bushings of the horizontal transmission shafts, P/N's 341A.34.1106.00, .01, or .03, and coupling shafts, P/N's 341A.34.1114.00, .01, or .02, to enable detection of relative rotation between bushings and shaft. (b) Upon the accomplishment of paragraph (a) of this AD and thereafter at intervals not to exceed 10 hours' time in service since the last inspection, inspect the bushings on both the horizontal transmission shaft and the coupling shaft for relative rotation between the bushings and the shaft, and rectify, as necessary, in accordance with subparagraph 1C(2) or Gazelle Service Bulletin No. 05.07, as revised June 18, 1975, or an FAA-approved equivalent. (c) Within the next 10 hours' time in service after the effective date of this AD and thereafter at intervals not to exceed 10 hours' time in service, since the last inspection, inspect the bearings on the coupling shaft and horizontal transmission shaft for grease leaks, rust run-outs, or seal damage and rectify, as necessary, in accordance with subparagraph 1C(3) of Gazelle Service Bulletin No. 05.07, as revised June 18, 1975, or an FAA-approved equivalent. (d) Within the next 10 hours' time in service after the effective date of this AD, and thereafter at intervals not to exceed 50 hours' time in service since the last inspection for assemblies 341A.34.1106.00, .01, and 341A.34.1114.00, or at intervals not to exceed 100 hours' time in service since the last inspection for assemblies 341A.34.1106.02, .03, and 341A.34.1114.01, .02, inspect bearings and attachment straps, and rectify, as necessary, in accordance with subparagraph 1C(4) of Gazelle Service Bulletin No. 05.07, as revised June 18, 1975, or an FAA-approved equivalent. This amendment becomes effective on January 30, 1976.
86-10-01: 86-10-01 PRATT & WHITNEY: Amendment 39-5292. Applies to Pratt & Whitney (PW) JT9D-3A series turbofan engines. Compliance is required as indicated, unless already accomplished. To preclude second stage turbine disk failures resulting from rearward deflection of the second stage turbine nozzle guide vane inner shroud, inspect second stage nozzle guide vanes, Part Number (P/N) 770372, in accordance with the Accomplishment Instructions of PW Alert Service Bulletin (ASB) 5619, dated July 31, 1985, or FAA approved equivalent, per the following schedule: (a) Inspect vanes for rearward deflection prior to accumulating 4,000 hours in service since new or since the vanes were refurbished, and reinspect thereafter per paragraph (b). (b) Reinspect at the following intervals and until such time as the engine incorporates a complete set of new or refurbished vanes with zero time in service, at which time the requirements of paragraph (a) become applicable. (1) Within the next 1,000 hours in service since last inspection, if the vane deflection is greater than 0.050 inches but not greater than 0.070 inches. (2) Within the next 2,000 hours in service since last inspection, if the vane deflection is less than or equal to 0.050 inches. (c) Remove from service, prior to further flight, vanes that have a rearward deflection greater than 0.070 inches. NOTES: 1. Refurbished vanes are defined as vanes which have been operated in service and have subsequently been inspected and repaired to the specifications in Pratt & Whitney Engine Manual, P/N 646028. 2. Engine Manuals P/N 646028 and 770407 are identical for the JT9D-3A engine model and are both FAA approved. Upon request, an equivalent means of compliance may be approved by the Manager, Engine Certification Office, Aircraft Certification Division, New England Region, Federal Aviation Administration, 12 New England Executive Park, Burlington, Massachusetts 01803. Aircraft may be ferried in accordance with the provisions of FAR Sections 21.197 and 21.199 to a base where the AD can be accomplished. Upon submission of substantiating data by an owner or operator through the FAA maintenance inspector, the Manager, Engine Certification Office, New England Region, may adjust the compliance time specified in this AD. PW ASB 5619, dated July 31, 1985, is incorporated herein and made a part hereof pursuant to 5 U.S.C. 552(a)(1). All persons affected by this directive who have not already received this document from the manufacturer may obtain copies upon request to Pratt & Whitney, Publication Department, P.O. Box 611, Middletown, Connecticut 06457. This document also may be examined at the Office of the Regional Counsel, New England Region, Federal Aviation Administration, 12 New England Executive Park, Burlington, Massachusetts 01803, Rules Docket Number 85-ANE-22, Room Number 311, between the hours of 8:00 a.m. and 4:30 p.m., Monday though Fridayexcept Federal holidays. This amendment becomes effective on June 5, 1986.
84-19-05: 84-19-05 GULFSTREAM AEROSPACE CORPORATION: Amendment 39-4925. Applies to Models 690 and 690A, (S/Ns 11001 through 11284 which have had engine isolator assemblies replaced after July 28, 1975); 690A (S/Ns 11285 through 11344); 690B (S/Ns 11350 through 11566); 690C (S/Ns 11600 through 11732); 690D (S/Ns 15001 through 15033 and 15037); 695 (S/Ns 95000 through 95084); 695A (S/Ns 96001 through 96061, 96063 through 96072, 96075, 96078, 96085, and 96088) airplanes certificated in any category. Compliance: Required as indicated, unless already accomplished. To prevent failure of the engine mount systems accomplish the following: (a) Within 50 hours time-in-service after the effective date of this AD, inspect and modify, if required, the engine mount systems in accordance with Gulfstream Aerospace Corporation Service Bulletin SB201 issued May 11, 1984. (b) Airplanes may be flown in accordance with FAR 21.197 to a location where this AD may be accomplished. (c) An equivalentmethod of compliance with this AD may be used if approved by the Manager, Airplane Certification Branch, ASW-150, FAA, Southwest Region, Post Office Box 1689, Fort Worth, Texas 76101; telephone (817) 877-2070. This amendment becomes effective on October 8, 1984.
2005-13-34: This amendment adopts a new airworthiness directive (AD), applicable to certain Boeing Model 777-200 and -300 series airplanes, that requires replacing existing ceiling and sidewall light connectors in the passenger cabin with new connectors, and follow-on actions. This action is necessary to prevent overheating of the light connectors, which could result in smoke and a possible fire in the passenger cabin. This action is intended to address the identified unsafe condition.
74-23-09: 74-23-09 BEECH: Amendment 39-2006. Applies to those Model 23 (Serial Numbers M- 1, M-2, M-4 through M-554), Model A23-19 (Serial Numbers MB-1 through MB-288), Model 19A (Serial Number MB-289 through MB-460), Model M19A (Serial Numbers MB-461 through MB-480), and Model B23 (Serial Numbers M-1095 through M-1284) airplanes which were originally approved in the Acrobatic Category and intentional spins in the Utility and Acrobatic Categories. Compliance: Required as indicated, unless already accomplished. To prevent inflight situations in which prompt spin recovery may not be assured, accomplish the following: A) Effective immediately intentional spins in the Utility and Acrobatic Categories are prohibited. B) Within the next 20 hours' time in service or ten (10) calendar days, whichever comes first, after the effective date of this AD, remove all placards pertaining to intentional spins and acrobatic flight and install in place thereof a placard to be conspicuouslylocated on the instrument panel which reads as follows: "THIS AIRPLANE MUST BE OPERATED AS A NORMAL OR UTILITY CATEGORY AIRPLANE. INTENTIONAL SPINS ARE PROHIBITED. NO ACROBATIC MANEUVERS APPROVED EXCEPT: CHANDELLES, LAZY EIGHTS, STEEP TURNS, AND STALLS (EXCEPT WHIP STALLS)." C) To reinstate the acrobatic category for those airplanes originally approved in the Acrobatic Category and intentional spins in Utility and Acrobatic Categories, install Beech spin improvement Kit No. 23-4007-1 or 23-4007-5 or subsequent revisions in accordance with instructions contained therein. Kit 23-4007-1 is applicable to the Models A23-19, 19A, M19A and B23 airplanes. Kit 23-4007-5 is applicable to the Model 23 serial numbers M1, M2, M4 thru M-554 airplanes. Any equivalent method must be approved by the Chief, Engineering and Manufacturing Branch, FAA, Central Region. Upon installation of the appropriate kit, the requirements of Paragraphs A and B of this AD are no longer applicable.NOTE: Kits from the manufacturer may not be available for some models until after December 15, 1974. This amendment becomes effective November 14, 1974.
97-14-14: This amendment adopts a new airworthiness directive (AD) that applies to certain Industrie Aeronautiche E Meccaniche (I.A.M.) Model Piaggio P-180 airplanes that are equipped with a certain freon air conditioning system. This AD requires inspecting the baggage compartment for stringer or air cycle machine (ACM) by-pass duct damage, repairing any damage found, and modifying the freon air inlet duct and electrical wiring. This AD results from trim system malfunction on one of the affected airplanes, resulting from contact between the freon air inlet duct and the electrical wiring. The actions specified by this AD are intended to prevent trim system malfunction caused by contact between the freon air inlet duct and electrical wiring, which could result in loss of control of the airplane.
70-02-06: 70-02-06 BRITTEN-NORMAN, LTD: Amdt. 39-914. Applies to Britten-Norman Models BN.2 and BN.2A airplanes. Compliance is required within the next 50 hours' time in service, unless already accomplished. To reduce the possibility of failure of the elevator trim tab attachment structure due to cracking, accomplish the following: (a) Visually inspect the elevator trim tab hinge attachment structure for cracks in the angle of the elevator trailing edge member and elevator skin forward of the trim tab. (b) If cracks are found during the inspection required by paragraph (a) which do not exceed four inches in length, repair the cracks in accordance with Britten-Norman Service Bulletin No. BN-2/SB.1, Issue 5, dated 23 June 1969, or an FAA-approved equivalent, before reinforcing the elevator structure as required by paragraph (d). (c) If cracks are found during the inspection required by paragraph (a) which exceed four inches in length, replace the cracked member before reinforcingthe elevator structure as required by paragraph (d). (d) Reinforce the elevator structure by modifying the elevator trailing edge structure at the trim tab outboard hinge in accordance with Britten-Norman Modification Leaflet No. BN.2/NB/M/339, Issue 1, dated 23 July 1969, or an FAA-approved equivalent. This amendment becomes effective January 11, 1970.
2016-11-22: We are adopting a new airworthiness directive (AD) for all Fokker Services B.V. Model F.28 Mark 0070 and 0100 airplanes. This AD was prompted by the need for more restrictive airworthiness limitations. This AD requires revising the maintenance or inspection program, as applicable, to incorporate certain maintenance requirement tasks, thresholds, and intervals. We are issuing this AD to reduce the potential for significant failure conditions and consequent loss of controllability of the airplane.
75-13-04: 75-13-04 PRATT & WHITNEY AIRCRAFT: Amendment 39-2244. Applies to all Pratt & Whitney Aircraft TF33-P-7 and TF33-P-7A turbofan engines containing thirteenth stage compressor disk, P/N 657913, fourteenth stage compressor disk, P/N 657914, fifteenth stage compressor disk, P/N 657915, and sixteenth stage compressor disk, P/N 657916. To ensure adequate life limit margin, remove from service thirteenth, fourteenth, fifteenth, and sixteenth stage compressor disks prior to exceeding the revised life limit listed below. Disk Part Number Previous Life Limit (Cycles) Revised Life Limit (Cycles) 657913 15,000 8,500 657914 15,000 8,500 657915 15,000 8,500 657916 15,000 8,500 This amendment becomes effective July 3, 1975.
2010-23-02: This amendment adopts a new airworthiness directive (AD) for the specified Eurocopter model helicopters. This action requires amending the Limitations section of the Rotorcraft Flight Manual (RFM) to limit the never-exceed velocity (VNE) to 150 Knots Indicated Air Speed (KIAS) and to add a 1,500 ft/minute rate of descent (R/D) limitation beyond 140 KIAS. This action also requires installing one or more placards on the cockpit instrument panel in full view of the pilot and co-pilot. This amendment is prompted by failures of the horizontal stabilizers on recently delivered Model AS 365 N3 helicopters. Tests indicate that the failures were due to a vibration phenomenon that may arise during the descent flight phases at high speed regardless of the stabilizer installed. The actions specified in this AD are intended to restrict the VNE, to prevent failure of the horizontal stabilizer, and subsequent loss of control of the helicopter.
2005-13-27: The FAA is adopting a new airworthiness directive (AD) for certain Boeing Model 737-300, -400, and -500 series airplanes. This AD requires repetitive inspections for cracking of the crown area of the fuselage skin, and corrective actions if necessary. This AD is prompted by a Model 737 fuselage structure test and fatigue analysis that indicate fuselage skin cracking could occur between 21,000 and 42,000 total flight cycles. We are issuing this AD to detect and correct fatigue cracking of the fuselage skin, which could cause the fuselage skin to fracture and fail, and could result in rapid decompression of the airplane.
2016-11-10: We are superseding airworthiness directive (AD) 2000-20-11 for BLANIK LIMITED Models L-13 Blanik and L-13 AC Blanik gliders (type certificate previously held by LET Aeronautical Works). This AD results from mandatory continuing airworthiness information (MCAI) issued by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as insufficient material strength of the tail-fuselage attachment fitting. We are issuing this AD to require actions to address the unsafe condition on these products.
2016-11-06: We are superseding Airworthiness Directive (AD) 2005-18-18 for certain The Boeing Company Model 757 airplanes. AD 2005-18-18 required inspections of certain wire bundles in the left and right engine-to- wing aft fairings for discrepancies; installation of back-to-back p- clamps between the wire and hydraulic supply tube at the aft end of the right-hand strut only; and associated re-routing of the wire bundles, if necessary. This new AD also requires an installation of spiral cable wrap on fuel shutoff valve (FSV) wires at the aft end of the strut, for both left and right engines, and related investigative and corrective actions. This AD was prompted by a determination that the service information referenced in AD 2005-18-18 did not adequately address FSV wires at the aft end of the struts. We are issuing this AD to prevent chafing between the wire bundle and the structure of the aft fairing, which could result in electrical arcing and subsequent ignition of flammable vapors and a possible uncontrollable fire.
2005-13-32: The FAA is adopting a new airworthiness directive (AD) for all Fokker Model F.28 Mark 1000, 2000, 3000, and 4000 airplanes. This AD requires a detailed inspection to determine the presence of incorrectly installed bushings in the attachment holes of the reinforcing strap of the left- and right-hand wings' lower skin, and corrective actions if necessary. This AD is prompted by a report that bushings were installed in accordance with improper procedures in the structural repair manual. We are issuing this AD to detect and correct improperly installed bushings, which could result in reduced tensile strength of the reinforcing strap of the wing's lower skin, and consequently a reduction of the structural capability of the wing and possible wing failure.
2000-15-11: This amendment adopts a new airworthiness directive (AD), applicable to certain McDonnell Douglas Model DC-8 series airplanes that have been converted from a passenger to a cargo-carrying ("freighter") configuration. This amendment requires a revision to the Airplane Flight Manual Supplement to ensure that the main deck cargo door is closed, latched, and locked; inspection of the door wire bundle to detect discrepancies and repair or replacement of discrepant parts. This amendment also requires, among other actions, modification of the hydraulic and indication systems of the main deck cargo door, and modification of the existing means to prevent pressurization to an unsafe level if the main deck cargo door is not closed, latched, and locked. This amendment is prompted by the FAA's determination that certain main deck cargo door systems and the existing means to prevent pressurization to an unsafe level if the main deck cargo door is not closed, latched, and locked, do not provide an adequate level of safety. The actions specified by this AD are intended to prevent opening of the cargo door while the airplane is in flight, and consequent rapid decompression of the airplane including possible loss of flight control or severe structural damage.
75-23-02: 75-23-02 AER PEGASO and CARMAM: Amendment 39-2413. Applies to Aer Pegaso M100S gliders, all serial numbers, and Carmam M200 gliders, except serial number 45 and subsequent, certificated in all categories. Compliance is required as indicated, unless already accomplished. To prevent possible structural failure of aileron spars accomplish the following: (a) Within the Next 10 hours' time in service after the effective date of this AD, and, thereafter, at intervals not to exceed 20 hours' time in service from the last inspection, visually inspect the aileron spar to the right of the central hinge for cracks. (b) If a crack is found during an inspection required by paragraph (a) of this AD, before further flight, reinforce the affected area with plates made of 1.5 mm thick birch plywood of aeronautical quality in accordance with Carmam Drawing, titled "Modification Aileron Central Part" dated April 12, 1968, or an FAA- approved equivalent. (c) Upon incorporationof the reinforcement specified in paragraph (b) of this AD, the inspections required by paragraph (a) of this AD may be discontinued. This amendment becomes effective November 14, 1975.
2000-22-10: This amendment supersedes an existing airworthiness directive (AD), applicable to certain EMBRAER Model EMB-135 and EMB-145 series airplanes, that currently requires various inspections to detect discrepancies of the elevator servo tab and spring tab hinge fittings of the horizontal stabilizer, and follow-on corrective actions, if necessary. This amendment clarifies certain fiberscopic inspection and replacement procedures, and corrective actions; revises the applicability of the existing AD; and adds an inspection procedure for the servo tab center hinge fittings to detect the presence of washers for both attaching fasteners, and follow-on corrective actions, if necessary. This amendment also provides for optional terminating action for the repetitive inspections. The actions specified in this AD are intended to prevent the linkage of the elevator servo tab or spring tab hinge fittings from separating from the horizontal stabilizer, which could result in loss of control of the airplane.
2005-13-29: The FAA is adopting a new airworthiness directive (AD) for certain Boeing Model 777-200 and -300 series airplanes. This AD requires inspecting for the installation of the tie plate for the wire bundles routed from lower section 41 into the center control stand in the flight deck; inspecting for any wire chafing or damage and repair if necessary; and installing a tie plate if necessary. This AD is prompted by a report of missing tie plates for the wire bundles. We are issuing this AD to prevent wire chafing, which could result in the loss of flight control, communication, navigation, and engine fire control systems. Loss of these systems could consequently result in a significant reduction of safety margins, an increase in flight crew workload, and in the case where loss of engine fire control is combined with an engine fire, could result in an uncontrollable fire.
66-19-01: 66-19-01 BRITISH AIRCRAFT: Amendment 39-265 Part 39 Federal Register July 26, 1966 as amended by Amendment 39-3121. Applies to Model BAC 1-11 Series Airplanes. Compliance required as indicated. To prevent fatigue damage to the rudder control system components, accomplish the following: (a) Within the next 3,000 hours' time in service after the effective date of this AD, unless already accomplished, rework rudder jacks to provide a shorter stroke in accordance with British Aircraft Corporation (BAC) One-Eleven Alert Service Bulletin 27-A-PM 1715 or later ARB-approved issue, or an equivalent approved by the Chief, Aircraft Certification Staff, FAA, Europe, Africa, Middle East Region. (b) Within the next 100 hours' time in service after the effective date of this AD or before the accumulation of 3,000 hours' time in service, whichever occurs later, and thereafter at intervals not to exceed 3,000 hours' time in service from the last replacement, replace ram rod eye end assemblies, P/N's P.183.45.65 and P.183.45.339, of the rudder power flying control unit on Series 200 airplanes only. (c) Within the next 100 hours' time in service after the effective date of this AD or before the accumulation of 10,000 hours' time in service, whichever occurs later, and thereafter at intervals not to exceed 10,000 hours' time in service from the last replacement, replace ram rod eye end assemblies, P/N P.183.45.363, of the rudder power flying control unit that have been operated with premodification PM1715 (Mark 1) rudder jacks installed. (d) Within the next 100 hours' time in service after the effective date of this AD or before the accumulation of 30,000 hours' time in service, whichever occurs later, and thereafter at intervals not to exceed 30,000 hours' time in service from the last replacement, replace ram rod eye end assemblies, P/N P.183.45.363, of the rudder power flying control unit that are installed with post-modification PM1715 (Mark 2) rudder jacks. (e) For a ram rod eye end assembly, P/N P.183.45.363, which has expended part of its life on pre-modification PM 1715 (Mark I) rudder jacks, determine the remaining life of the ram rod eye end on a post-modification PM 1715 (Mark II) rudder jack on a pro-rata basis by which the established life limit for the part as installed on the post modification PM 1715 rudder jack is reduced by the percentage of the life limit expended prior to incorporation of modification PM 1715. Amendment 39-265 became effective August 25, 1966. This amendment 39-3121 becomes effective January 23, 1978.
97-14-07: This amendment supersedes an existing airworthiness directive (AD), applicable to certain Lockheed Model L-1011 series airplanes, that currently requires several modifications of the engine high speed gearboxes. This amendment requires that a new modification be installed in lieu of one of those previously required. This amendment is prompted by a report indicating that one of the currently required modifications is not completely effective because it can create interference problems between the fireloop and a fuel line. The actions specified by this AD are intended to reduce the possibility of a fire in the high speed gear boxes, and to ensure that any fire which may occur is readily detected by the flight crew.
99-25-09: This amendment adopts a new airworthiness directive (AD), applicable to all Dassault Model Mystere-Falcon 50 and 900 series airplanes, Falcon 900EX series airplanes, and Falcon 2000 series airplanes, that requires revising the Airplane Flight Manual to provide the flight crew with certain instructions associated with the onset of stall warning. This amendment also requires repetitive inspections to detect discrepancies of the hinge pin assemblies of the rear horizontal stabilizer, and corrective actions, if necessary. For certain airplanes, this amendment also requires replacement of the hinge pin assemblies with new, improved parts. This amendment is prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified by this AD are intended to prevent excessive movement and consequent deformation of the hinge pin assemblies of the rear horizontal stabilizer, which could result in flutter and possible failure of the rear horizontal stabilizer.