Results
2004-13-19: This amendment adopts a new airworthiness directive (AD), applicable to certain Airbus Model A300 B2 and A300 B4; Model A300 B4- 600, B4-600R, C4-605R Variant F, and F4-600R (collectively called A300- 600); and Model A310 series airplanes. This AD requires an inspection to determine the part number of certain passenger/crew escape slides; and related investigative action and corrective action, if necessary. This action is necessary to prevent the failure of an escape slide to deploy during emergency evacuation, which could impede an evacuation and result in injury to flightcrew and passengers. This action is intended to address the identified unsafe condition.
47-33-01: 47-33-01 DOUGLAS: (Was Mandatory Note 19 of AD-762-7.) Applies to All DC-4 and C-54 Type Aircraft Except Production DC-4 Aircraft Serial Numbers 42952, 42992, and Subsequent. \n\n\tThe following is to be accomplished to reduce the possibility of wear of the outboard elevator hinge parts; Inspect immediately for wear, proper installation and operation unless already accomplished, and at periods thereafter not to exceed 250 hours flight time, or in the case of Scheduled Air Carrier Operations, at each major inspection closest to 250 hours until the following mandatory rework is accomplished. (This mandatory rework shall be accomplished not later than October 15, 1947.) \n\n\t(a)\tEach horizontal stabilizer outer hinge bracket P/N 5109899, must be reworked as follows: \n\n\t\t(1)\tLine ream 0.3745-0.3755-inch diameter holes through the two lugs at each hinge point. \n\n\t\t(2)\tPress in 3323406-A-2 bushings, two required, made from 9/16-inch diameter corrosion resistant steel bar, Spec. AN-QQ-S-771, Comp. FM, Cond. B., or bushing, P/N 1356866, which may be purchased from the airplane manufacturer. \n\n\t\t(3)\tMachine shoulders of bushings on inside of lugs to obtain clearance for bearing in eyebolt of 0.563 inch, plus 0.005 inch and minus 0.001 inch. Minimum thickness of shoulder on each bushing after machining should not be less than 0.020 inch. \n\n\t\t(4)\tLine ream hole 0.3120-0.3140 inch in diameter through bushings after pressing into hinge fitting. \n\n\t\t(5)\tRemove outboard elevator hinge eyebolt assembly, P/N 2110992, and install new assembly, P/N 2328991. \n\n\t\t(6)\tReinstall elevators using 2357035-15 bolt through bushed hinge bracket and new eyebolt assembly, with 1357162 washer (two required-one under head of bolt and one under nut), AN 310-5 nut and AN 380-2-2 cotter pin. \n\n\t(b)\tThe horizontal stabilizer outer hinge bracket, P/N 5109899, was replaced in later production aircraft and on some aircraft in the field with P/N 3323406. This latter bracket incorporates a 5/16-inch bolt with eyebolt P/N 2328991, and must be reworked in accordance with parts 1, 2, 3, 4, and 6 of paragraph (a). \n\n\t(Douglas Service Bulletin DC-4, No. 73 dated September 23, 1947, covers this same subject. An earlier issue of this Service Bulletin dated June 12, 1947, called for NAS 55-15 bolts in paragraph (a)(6). It is satisfactory to leave the NAS 55-15 bolts installed on airplanes reworked as per the original issued of the Service Bulletin.)
2022-03-07: The FAA is adopting a new airworthiness directive (AD) for certain Stemme AG TSA-M Model S6 and S6-RT gliders. This AD was prompted by mandatory continuing airworthiness information (MCAI) issued by the aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as a new version of the propeller gearbox tooth belt with a reduced life limit. This AD requires establishing a life limit of 5 years for certain propeller gearbox tooth belts. The FAA is issuing this AD to address the unsafe condition on these products.
84-13-03 R1: 84-13-03 R1 CANADAIR: Amendment 39-4882 as amended by Amendment 39-5083. Applies to Model CL-600-1A11 (CL-600) and Model CL-600-2A12 (CL-601) airplanes, certificated in all categories. Compliance required as indicated. A. To detect possible fatigue cracks in the outboard flap vane support structure, accomplish the following inspections for cracks on each side of the aircraft within 200 landings after the effective date of this AD, unless already accomplished within the last 200 landings, and thereafter at intervals not to exceed 400 landings. 1. Visually inspect the following parts: a. The flap vane support straps, P/N 600-10460-13 and -23, at the inboard and outboard ends of the outboard flap. b. The lower skins on the outboard flap vanes with particular attention given to the spanwise direction at the mid-chord position and the chordwise direction adjacent to the vane attachment points. c. The three vane main support fittings and two vane intermediate support fittings attached to the outboard flap vane. P/N 600-14562-1 and -2 (FS 189) P/N 600-14563-1 and -2 (FS 235) Main Supports: P/N 600-14564-1 and -2 (FS 280) Intermediate Supports: P/N 600-14588-1 and -2 (FS 209) or P/N 600-14586-1 and -2 (FS 209) or P/N K600-14502-5 and -6 (FS 209) P/N 600-14589-1 and -2 (FS 254) or P/N 600-14585-1 and -2 (FS 254) or P/N K600-14502-7 and -8 (FS 254) Particular attention should be given to the root of the attachment lugs. d. The two intermediate support blades attached to the outboard flap leading edge structure. P/N 600-10463-35 (FS 209) or P/N K600-14502-1 (FS 209) P/N 600-10463-37 (FS 254) or P/N K600-14502-3 (FS 254) 2. Conduct an eddy current or dye-penetrant inspection of the following parts: The three outboard flap vane main support blades which form an integral part of the outboard flap hinge fittings. P/N 600-14543-1 and -2 (FS 189) P/N 600-14546-1, -2, -3, and -4 (FS 235) P/N 600-14547-1 and -2 (FS 280) This must be accomplished along the root radius at the bottom edge of the blade where it passes through the leading edge of the flap. To accomplish this inspection, it is necessary to remove the sealant from the root radius. Reseal after inspection. B. Parts found cracked during inspection must be replaced with serviceable or new parts prior to further flight. After replacement, continue to inspect in accordance with paragraph A., above. C. Alternate means of compliance, which provide an equivalent level of safety may be used when approved by the Manager, New York Aircraft Certification Office, FAA, New England Region. D. Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base for the accomplishment of inspections and door modifications required by this AD. E. Upon submission of substantiating data by an owner or operator through an FAA maintenance inspector, the Manager, New York Aircraft Certification Office, FAA, New England Region, may adjust the repetitive inspection intervals required by this AD. This supersedes Amendment 39-4687 (48 FR 33245; July 21, 1983), AD 83-14-06, and telegraphic AD T83-20-51 issued September 30, 1983. Amendment 39-4882 became effective June 27, 1984. This Amendment 39-5083 becomes effective July 26, 1985.
95-15-10: This amendment adopts a new airworthiness directive (AD), applicable to certain Jetstream Model 4101 airplanes, that requires an inspection to determine if a travel stop (screw) is installed at the flight control assembly, and various follow-on actions. This amendment is prompted by a report of failure of the travel stop, which allowed the elevator and aileron disconnect handles to rotate within the housing due to migration of the travel stop from its position. The actions specified by this AD are intended to prevent such migration, which could result in the elevator and aileron disconnect system resetting without the use of the reset button; this condition could lead to jamming of the disconnect handles.
2022-02-18: The FAA is adopting a new airworthiness directive (AD) for all General Electric Company (GE) CF6-80C2A1, CF6-80C2A2, CF6-80C2A3, CF6- 80C2A5, CF6-80C2A5F, and CF6-80C2A8 model turbofan engines with an installed left-hand rear mount link assembly, part number (P/N) 1846M23G01. This AD was prompted by the manufacturer reducing the life limit for the affected left-hand rear mount link assembly. This AD requires revising the airworthiness limitations section (ALS) of the existing engine maintenance manual and the operator's existing approved continuous airworthiness maintenance program (CAMP). The FAA is issuing this AD to address the unsafe condition on these products.
2004-13-18: This amendment adopts a new airworthiness directive (AD), applicable to certain Gulfstream Aerospace LP Model Astra SPX, and 1125 Westwind Astra series airplanes; and Model Gulfstream 100 airplanes. This AD requires a one-time inspection of the outboard doors of the main landing gear (MLG) for evidence of impact with the surrounding structure, and for damage to the door seals and seal channels; measurements for adequate gaps and clearances; and related investigative and corrective actions, if necessary. This action is necessary to prevent damage to or breakage of the MLG outboard doors, which could result in the loss of a door during flight, and consequent damage to the airplane and injury to people or damage to property on the ground. This action is intended to address the identified unsafe condition.
2021-26-23: The FAA is superseding Airworthiness Directive (AD) 2017-22- 06, which applied to certain Bombardier, Inc., Model CL-600-2B16 (601- 3A, 601-3R, and 604 Variants) airplanes. AD 2017-22-06 required repetitive inspections for fuel leakage at the engine and auxiliary power unit (APU) fuel pumps, and related investigative and corrective actions if necessary. This AD retains the requirements of AD 2017-22- 06, and requires an inspection of the APU, repair if necessary, and modification of the engine electrical fuel pump (EFP) installation. This AD also adds airplanes to the applicability. This AD was prompted by reports of fuel leaks from the electrical connectors and conduits of the engine and APU EFP cartridge/canister, and the development of additional actions to address the root cause of the fuel leaks. The FAA is issuing this AD to address the unsafe condition on these products.
86-10-04: 86-10-04 AVCO LYCOMING: Amendment 39-5299. Applies to Avco Lycoming Model LTS101-600A-2, -600A-3, -650A-2, -650B-1, -650B-1A, -650C-2, -650C-3, -650C-3A, -750A-1, -750A-3, -750B-2, and -750C-1 turboshaft; and LTP101-600A-1A, and -700A-1A turboprop engines. Compliance is required on or before June 1, 1986, for engine models LTS101-600A-2, -600A-3, and -750C-1; and on or before September 30, 1986, for all other affected LT101 series engine models, unless already accomplished. To prevent the failure of a gas producer (G.P.) blade due to fatigue cracking from excessive vibratory stresses, incorporate G.P. blade dampeners in accordance with Avco Lycoming Service Bulletin (SB) Number LT101-72-50-0079, Revision 1, dated April 21, 1986, or FAA approved equivalent. 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 request, an equivalent means of compliance with the requirements of this AD may be approved by the Manager, Engine Certification Office, New England Region, 12 New England Executive Park, Burlington, Massachusetts 01803. Upon submission of substantiating data by an owner or operator through an FAA maintenance inspector, the Manager, Engine Certification Office, New England Region, may adjust the compliance dates specified in this AD. Avco Lycoming SB Number LT101-72-50-0079, Revision 1, dated April 21, 1986, identified and described in this document, 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 Avco Lycoming Williamsport Division, 652 Oliver Street, Williamsport, Pennsylvania 17701, Attention: Customer Support. This document also may be examined at the Office of the Regional Counsel, Rules Docket Number 86- ANE-14, Federal Aviation Administration, 12 New England Executive Park, Burlington, Massachusetts 01803, between the hours of 8:00 a.m. and 4:30 p.m., Monday through Friday except Federal holidays. This amendment becomes effective on May 16, 1986.
99-01-14: This amendment adopts a new airworthiness directive (AD), applicable to certain Honeywell IC-600 integrated avionics computers, that requires modification of the integrated avionics computers. This amendment is prompted by a report of integrated avionics computer failures, which caused a "random reset" condition of the electronic flight instrument system. The actions specified by this AD are intended to prevent such "random reset" conditions, which could affect the pilot s ability to control the airplane.
94-22-05: This amendment adopts a new airworthiness directive (AD), applicable to certain Fokker Model F28 Mark 0100 series airplanes, that requires inspections to detect cracks of certain demountable flange (inboard) wheel subassemblies and of the bolt bosses on certain demountable flange (outboard) wheel subassemblies, and modification or replacement of the wheel subassemblies. This amendment is prompted by reports of cracks and broken spokes found on certain main wheel assemblies of these airplanes. The actions specified by this AD are intended to prevent loss of a main wheel assembly during takeoff or landing.
2022-02-15: The FAA is superseding Airworthiness Directive (AD) 2020-12-06 for all Gulfstream Aerospace Corporation (Gulfstream) Model G-IV airplanes. AD 2020-12-06 required replacing the nose wheel steering servo valve manifold, incorporating revised operating procedures into the airplane flight manual (AFM), doing a records inspection for any incidents of un-commanded nose wheel steering turns, and reporting the results to the FAA. Since the FAA issued AD 2020-12-16, the FAA determined that a typographical error was made in citing one of the AFM documents. This AD retains the actions of AD 2020-12-06 and corrects the citation to the AFM. The FAA is issuing this AD to address the unsafe condition on these products.
88-03-06: 88-03-06 TELEDYNE CONTINENTAL MOTORS (TCM): Amendment 39-5888. Applies to IO-360, TSIO-360, O-470, IO-470, TSIO-470, IO-520, TSIO-520, GTSIO-520, and IO-550 series engines equipped with oil filters. Compliance is required at the next oil change or within 10 flight hours, whichever occurs first, unless already accomplished. To prevent possible loss of engine oil and subsequent engine failure, accomplish the following: (a) Determine if oil filter TCM P/N 649309 or 649310 is installed. (1) If neither filter is installed, proceed to paragraph (b). (2) If P/N 649309 is installed, replace with P/N 649923 or equivalent Parts Manufacturer Approval (PMA) product. (3) If P/N 649310 is installed, replace with P/N 649922 or equivalent PMA product. (b) Make appropriate log book entry showing compliance with this AD. (c) Aircraft may be ferried in accordance with the provisions of Federal Aviation Regulations 21.197 and 21.199 to a base where this AD can be accomplished. (d) Upon request, an equivalent means of compliance with the requirements of this AD may be approved by the Manager, Atlanta Aircraft Certification Office, Federal Aviation Administration, 1669 Phoenix Parkway, Suite 210C, Atlanta, Georgia 30349. (e) Upon submission of substantiating data by an owner or operator, through an FAA maintenance inspector, the Manager, Atlanta Aircraft Certification Office, may adjust the compliance time specified in this AD. NOTES: (1) TCM Service Bulletin No. M88-4, dated January 15, 1988, refers to this subject. (2) TCM oil filter P/N's 649309 and 649310, in inventory, should be returned to TCM in accordance with the TCM service bulletin referenced in Note 1. This amendment, 39-5888, becomes effective April 15, 1988, as to all persons except those persons to whom it was made immediately effective by individual priority letter AD 88-03-06, issued February 5, 1988, which contained this amendment.
99-01-03: This amendment supersedes Airworthiness Directive (AD) 97-14- 16, which applies to Raytheon Aircraft Company (Raytheon) Models 1900, 1900C, and 1900D airplanes. AD 97-14-16 currently requires repetitively inspecting the outboard flap support roller bearings and flap attachment brackets for indications of contact (wear), inspecting for elongated holes in the flap attachment brackets, repairing or replacing any part showing wear, and replacing any bracket with elongated holes. AD 97-14-16 was the result of five incidents where the flap roller bearings rubbed on the flap attachment brackets and resulted in aileron interference. This AD retains the repetitive inspection requirement of AD 97-14-16, but reduces the number of ground-air-ground (GAG) cycles allowed between inspections and lowers the total number of accumulated GAG cycles allowed before mandatory accomplishment of the initial inspection. This AD also provides the option of replacing the outboard flap roller bearings with parts of improved design as terminating action for the repetitive inspection requirement. The actions specified by this AD are intended to prevent asymmetric flaps, jammed flaps, and/ or possible interference between the flap and the aileron, which could inhibit aileron travel and result in possible loss of roll control of the airplane.
65-15-03: 65-15-03 CONSOLIDATED AERONAUTICS: Amdt. 39-103 Part 39 Federal Register July 1, 1965. Applies to Model Lake LA-4 Aircraft. Compliance required within the next 25 hours' time in service after the effective date of this AD unless already accomplished. To prevent failure of the nose landing gear to latch in the down and locked position, accomplish the following: (a) Inspect the bolt at the top of the nose gear drag strut at Fuselage Station 12 5/8 that connects the upper drag strut assembly, Lake P/N 2-4411-1, to the support assembly plates, Lake P/N 2-4412-27, to ensure that an AN5-16A bolt or an FAA-approved equivalent is installed and that the bolt head is on the right-hand side of the aircraft. (b) If an AN5-15A bolt is installed, remove the bolt and visually inspect the bolt hole of the upper drag strut assembly and both support assembly plates for elongation. (c) Rework any part having an elongated bolt hole in accordance with Consolidated Aeronautics, Inc., Lake Aircraft Division, Service Letter No. 11B, dated February 22, 1965, or an equivalent approved by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region, or replace the part with a new part of the same part number or an equivalent approved by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region. (d) Replace any AN5-15A bolt with an AN5-16A bolt or an AN5-17A bolt as necessary when bushings are installed or an FAA-approved equivalent, installing the bolt with the head on the right-hand side of the aircraft. (e) Reverse any AN5-16A bolt that is installed with the head on the left-hand side of the aircraft. This directive effective July 1, 1965.
2021-26-25: The FAA is adopting a new airworthiness directive (AD) for certain Schempp-Hirth Flugzeugbau GmbH Model Duo Discus and Duo Discus T gliders. This AD was prompted by mandatory continuing airworthiness information (MCAI) originated 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 jerky extension of the air brakes at very high air speeds, including cases where the air brake blades interlock. This AD requires replacing certain air brake end stop bushings, inspecting certain other air brake end stops, and repairing if necessary. The FAA is issuing this AD to address the unsafe condition on these products.
2022-02-16: The FAA is adopting a new airworthiness directive (AD) for all The Boeing Company Model 787-8, 787-9, and 787-10 airplanes. This AD was prompted by a determination that radio altimeters cannot be relied upon to perform their intended function if they experience interference from wireless broadband operations in the 3.7-3.98 GHz frequency band (5G C-Band), and a recent determination that, during landings, as a result of this interference, certain airplane systems may not properly transition from AIR to GROUND mode when landing on certain runways, resulting in degraded deceleration performance and longer landing distance than normal due to the effect on thrust reverser deployment, speedbrake deployment, and increased idle thrust. This AD requires revising the limitations and operating procedures sections of the existing airplane flight manual (AFM) to incorporate limitations prohibiting certain landings and the use of certain minimum equipment list (MEL) items, and to incorporate operating procedures for calculating landing distances, when in the presence of 5G C-Band interference as identified by Notices to Air Missions (NOTAMs). The FAA is issuing this AD to address the unsafe condition on these products.
89-14-07: 89-14-07 AEROSPATIALE: Amendment 39-6257. Applicability: Model ATR42-300 series airplanes, Serial Numbers 003 through 052, certificated in any category. Compliance: Required as indicated, unless previously accomplished. To prevent failure of the emergency exit frame, accomplish the following: A. Prior to the accumulation of 12,000 landings or within 60 days after the effective date of this AD, whichever occurs later, accomplish modification of the fuselage emergency exit frame in accordance with Aerospatiale Service Bulletin ATR42-53-0024, Revision 2, dated May 16, 1988. B. An alternate means of compliance or adjustment of the compliance time, which provides an acceptable level of safety, may be used when approved by the Manager, Standardization Branch, ANM-113, FAA, Northwest Mountain Region. NOTE: The request should be forwarded through an FAA Principal Maintenance Inspector (PMI), who will either concur or comment and then send it to the Manager, Standardization Branch, ANM-113. C. Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base in order to comply with the requirements of this AD. All persons affected by this directive who have not already received the appropriate service documents from the manufacturer may obtain copies upon request to Aerospatiale, 316 Route de Bayonne, 31060 Toulouse, Cedex 03, France. These documents may be examined at the FAA, Northwest Mountain Region, Transport Airplane Directorate, 17900 Pacific Highway South, Seattle, Washington, or at the Standardization Branch, 9010 East Marginal Way South, Seattle, Washington. This amendment (39-6257, AD 89-14-07) becomes effective on August 7, 1989.
47-36-02: 47-36-02 DOUGLAS: (Was Mandatory Note 2 of AD-3L-1.) Applies to A-26B and A-26C Aircraft. Compliance required prior to operation in cold weather and not later than next engine overhaul. To preclude collapse of the oil screen during cold weather starting, replace oil screen assembly No. 51887 with oil screen assembly Nos. 51887M or 107547. P/N 51887 may be reworked to P/N 51887M by incorporating reinforcing spring No. 107542 and adding the letter "M" to the part number.
2004-13-17: This amendment supersedes an existing airworthiness directive (AD), applicable to certain Fokker Model F.28 Mark 0070 series airplanes, that currently requires a one-time inspection to detect loose bolts attaching the gustlock counter-bracket to the pulley on the elevator tension regulator (control) assembly, and corrective action if necessary. This AD instead requires a modification of the elevator tension control mechanism. This AD also revises the applicability to include additional airplanes. The actions specified by this AD are intended to prevent restricted elevator movement and consequent reduced controllability of the airplane. This AD is intended to address the identified unsafe condition.
53-10-02: 53-10-02 de HAVILLAND: Applies to Model DHC-2 (Beaver) Aircraft, Serial Numbers 1 to 401 Inclusive. Compliance required as indicated. After the aircraft has acquired 500 hours of flying time and pending the incorporation of the recommended repair, the wings should be inspected for cracks in lower wing skin at ends of the short stringers at the root end station of the wing leading edges at 50-hour intervals. If no cracks are evident reinforcements should be installed on the bottom surface of the wing as a preventive measure. The FAA concurs in this mandatory action by the Canadian Department of Transport. (de Havilland Technical News Sheet Series B, No. 59 - Issue 2 dated January 15, 1953, available from de Havilland Aircraft of Canada, Ltd., Toronto, Ontario, Canada, covers this same subject and describes method of reinforcement.)
2021-26-26: The FAA is superseding Airworthiness Directive (AD) 2005-12-08 for certain Safran Helicopter Engines, S.A. (Safran Helicopter Engines) Arrius 2B1, 2B1A, 2B1A-1, and 2B2 model turboshaft engines. AD 2005-12- 08 required replacing the software in the engine electronic control unit (EECU). This AD was prompted by a report of simultaneous loss of automatic control on both engines installed on an Airbus Helicopters Deutschland (formerly Eurocopter Deutschland) EC135 helicopter during flight. This AD requires replacement of the EECU or upgrade of the EECU software for engines with a certain EECU part number (P/N) installed. This AD also prohibits installation of an affected EECU onto any engine. The FAA is issuing this AD to address the unsafe condition on these products.
2012-12-21: We are superseding an existing airworthiness directive (AD) for all Eurocopter Deutschland GmbH (ECD) Model MBB-BK 117 C-2 helicopters. That AD currently requires revising the ``Emergency and Malfunction Procedures'' and ``Performance Data'' sections of the Rotorcraft Flight Manual (RFM) by inserting three temporary pages into the RFM to alert pilots to monitor the power display when a generator is deactivated and provides procedures to prevent failure of the remaining generator. Before we issued that AD, the manufacturer developed a procedure to modify the two ``After Junction Boxes'' by removing a diode from each box, which provides terminating action for our AD requirements. These actions are intended to require implementing this terminating action to prevent an electrical power system failure and subsequent loss of control of the helicopter and revising the RFM accordingly, by removing the temporary pages inserted to comply with the superseded AD.
95-03-07: This amendment adopts a new airworthiness directive (AD), applicable to certain Aerospatiale Model ATR72 series airplanes, that requires an inspection to determine the model and orientation of certain flight control rods, and replacement of the rods with modified rods, if necessary. This amendment is prompted by reports of corrosion found on the pitch and rudder trim and rudder travel limiter fail-safe rods. The actions specified by this AD are intended to prevent problems associated with corrosion of the flight control rods, which could compromise the required strength of these items.
48-19-03: 48-19-03\tDOUGLAS: Applies to DC-6 Serial Numbers 42854 Through 42896; 43000 Through 43024; 43035 Through 43052; 43055 Through 43058; 43061 Through 43064; and 43105 through 43110. \n\n\tCompliance required by September 15, 1958. \n\n\tDue to two failures in flight and to reported excessive looseness in the elevator trim tab operating mechanism, the following must be accomplished: \n\n\t1.\tRework drum, P/N 4344461 into drum, P/N 4357010-4, by boring hole in end of drum 0.8755-0.8745 diameter, 0.188-0.189 deep and concentric within 0.002 full indicator reading, and press in bushing 4357010-2 into hole. Remove nut, P/N 2335472, press in nut, P/N 2357008, in place so that two holes in nut match two holes in drum, P/N 4357010-4, and insert two pins, P/N 1335480, and stake in place. This rework changes jackshaft mechanism assembly, P/N 434460, into P/N 4357010. \n\n\t2.\tRework push-pull tubes, P/N 2344790, into P/N 2357984-2 by cutting off swaged end of tube 1/8 inch so that new tube lengthis 10 inches. Insert large end of plug, P/N 2357980, into tube 1 3/4 inches, drill two 0.161 diameter holes (No. 20 drill) and attach plug to tube with two rivets, P/N AN 430 AD5-16. Machine hex end on socket, P/N 2331924, and install in end of the tube opposite to plug, P/N 2357980. Rework end assemblies, P/N 2331925 into end assemblies, P/N 2357983, and install with locknuts, P/N AN 316-5R and washer 1357982. \n\n\tReassemble trim tab mechanism and install on aircraft. \n\n\t(Douglas Service Bulletin DC-6 No. 123 covers this same subject.)