Results
2011-15-06: We are adopting a new airworthiness directive (AD) for the products listed above. This AD requires initial and repetitive fluorescent penetrant inspections (FPIs) and eddy current inspections (ECIs) of the high-pressure compressor rotor (HPCR) 8-10 stage spool, part numbers (P/Ns) 1844M90G01 and 1844M90G02, for cracks between the 9-10 stages at each piece-part exposure. This AD was prompted by cracks discovered on one HPCR 8-10 spool between the 9-10 stages in the weld joint. We are issuing this AD to prevent failure of the HPCR 8-10 stage spool, uncontained engine failure, and damage to the airplane.
2011-12-13: We are adopting a new airworthiness directive (AD) for the products listed above. This AD requires repetitive testing of the stabilizer takeoff warning switches, and corrective actions if necessary. This AD was prompted by reports that the warning horn did not sound during the takeoff warning system test of the S132 ''nose up stab takeoff warning switch.'' We are issuing this AD to detect and correct a takeoff warning system switch failure, which could reduce the ability of the flightcrew to maintain the safe flight and landing of the airplane.
2003-01-04: This amendment adopts a new airworthiness directive (AD) for the specified Bell Helicopter Textron Inc. (BHTI) model helicopters. This action requires conducting various inspections associated with the main rotor grip (grip). If a crack is found, this AD requires replacing the grip before further flight. If delamination of the buffer pad on the grip tang inner surface is found, this AD requires inspecting the grip surface for corrosion or other damage and repairing or replacing the grip if corrosion or other damage is found. This AD also requires determining and recording the hours time-in-service (TIS) and the engine start/stop cycles for each grip on a component history card or equivalent record. Also, this action requires reporting certain inspection results and information to the FAA. This amendment is prompted by the discovery of 13 grips that cracked in the lower tang, three of which cracked in flight. The actions specified by this AD are intended to prevent failure of agrip, separation of a main rotor blade, and subsequent loss of control of the helicopter.
97-09-06: This amendment adopts a new airworthiness directive (AD) that is applicable to all Boeing Model 757 series airplanes. This action requires repetitive inspections to detect damage of the tubes of the fire extinguishing and smoke detection systems, and duct support brackets of the auxiliary power unit (APU); and corrective actions, if necessary. This amendment is prompted by reports of incidents in which the tubes of the fire extinguishing and smoke detection systems chafed against the stiffener rings and support brackets of the pneumatic duct of the APU. The actions specified in this AD are intended to detect and correct such chafing, which could result in a hole in the tube of the fire extinguishing system and consequently, could prevent the proper distribution of the fire extinguishing agent within the aft cargo compartment in the event of a fire. Such chafing also could result in a hole in the smoke detection system, which could result in the delay of detection of a fire in the aft cargo compartment.
2011-14-01: We are adopting a new airworthiness directive (AD) for the products listed above. This AD results from 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: An operator of an A300-600 aeroplane reported finding a cracked pylon fuel drain pipe on engine 1. * * * * * * The pipe drains the double wall of the wing-to-pylon junction in the event of fuel leakage. After investigation, it was concluded that the damage of the pylon fuel drain pipe had been caused by chafing of the pipe against over-length screws that had been installed in accordance with the Illustrated Parts Catalogue (IPC) during a maintenance phase of the Lower Aft Pylon Fairing (LAPF). This condition, if not detected and corrected, could, in combination with fuel leakage in the pylon, lead to an accumulation of fuel in the lowest pointof the LAPF. As high temperatures are present within the [[Page 39249]] LAPF, and without ventilation, this could result in fuel (vapour) ignition and consequent fire. * * * * * We are issuing this AD to require actions to correct the unsafe condition on these products.
64-19-06: 64-19-06 VERTOL: Amdt 782 Part 507 Federal Register August 7, 1964. Applies to Models 42A, 42B (Military H21B, H21C), 44A and 44B Helicopters. Compliance required as indicated. A spiral bevel pinion gear P/N 42D2043-2 installed in an aft transmission of a Vertol Model 42/44 Series helicopter recently failed. The nature of the failure indicated that metallurgical processing was a contributing factor. The gears listed herein were manufactured in the same carburizing and heat treat lot. These gears must be removed from service and replaced as follows: (a) Remove from service any spiral bevel pinion gear P/N 42D2043-2 listed in paragraph (b) and replace it in accordance with the V44-28 rotor transmission overhaul manual at the following times: (1) Within 10 hours' time in service after the effective date of this AD for those gears which have 500 or more hours' time in service on the effective date of this ad. (2) Within 50 hours' time in service after theeffective date of this AD for those gears which have less than 500 hours' time in service on the effective date of this AD. (b) The following spiral bevel pinion gears P/N 42D2043-2 shall be removed from service in accordance with paragraph (a): Gear S/N - P2009; Aft Transmission S/N - P-9-1653 Gear S/N - P2008; Aft Transmission S/N - P-9-1665 Gear S/N - P2001; Aft Transmission S/N - P-9-1657 Gear S/N - P1999; Aft Transmission S/N - P-9-1640 Gear S/N - P1997; Aft Transmission S/N - P-9-1646 Gear S/N - P1977; Aft Transmission S/N - P-9-1642 Gear S/N - P1972; Aft Transmission S/N - P-9-1405 Gear S/N - P2007 Gear S/N - P1995 Gear S/N - P1962 Gear S/N - P1961 NOTE. - It is believed that the aft transmission S/N's listed above have the corresponding gear S/N listed. It is not known which aft transmission S/N's may have the remaining listed gear S/N's. (Vertol Division Technical Memorandum SDTMNo. 2059 dated May 19, 1964, covers this subject.) This directive effective August 7, 1964.
64-14-04: 64-14-04 DORNIER: Amdt. 748 Part 507 Federal Register June 16, 1964. Applies to Model DO-28 A1 Aircraft Serial Numbers 3024 through 3060 and All Model DO-27 Q6 Aircraft Equipped With Landing Flap Actuating Levers Without a Control Grip. Compliance required within the next 100 hours' time in service after the effective date of this AD. In order to preclude an unintentional retraction of flaps, modify all levers without control grips by installing a cover in accordance with Dornier Technical Bulletin No. 27-18 dated October 16, 1963, for Model DO-27 Q6 aircraft and Bulletin No. 28-12 dated October 16, 1963, for Model DO-28 A1 aircraft. (Dornier Technical Bulletins No. 27-18 dated October 16, 1963, and No. 28-12 dated October 16, 1963, cover this same subject.) This directive effective July 17, 1964.
2011-14-04: We are adopting a new airworthiness directive (AD) for the products listed above. This AD results from 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: On some Falcon 7X aeroplanes, it has been determined potential low clearance between electrical wiring or hydraulic pipe and nearby structure. Although no in service incident has been reported, there is no certainty that the minimum clearances would be maintained over time. In the worst case, interference or contact with structure might occur and lead to electrical short circuits or fluid leakage, potentially resulting in loss of several functions essential for safe flight. * * * * * [[Page 39257]] We are issuing this AD to require actions to correct the unsafe condition on these products.
2003-01-02: This amendment adopts a new airworthiness directive (AD), applicable to certain Bombardier Model CL-600-2B19 (Regional Jet Series 100 & 440) series airplanes, that requires replacement of the existing smoke detectors in the cargo compartment with new, improved smoke detectors. This amendment is prompted by mandatory continuing airworthiness information from a civil airworthiness authority. The actions specified by this AD are intended to prevent false smoke warnings from the smoke detectors in the cargo compartment. A false smoke warning prompts the flightcrew to discharge fire extinguisher bottles, leaving those bottles depleted in the event of an actual fire. Repeated false smoke warnings create uncertainty as to whether an emergency landing and emergency evacuation of passengers and flightcrew is warranted.
64-12-03: 64-12-03 DOUGLAS: Amdt. 741 Part 507 Federal Register June 3, 1964 as amended by Amendment 39-1291 and 39-1360 is further amended by Amendment 39-2258. Applies to All Models A-26B (Later USAF Designation B-26B) and A-26C (Later USAF Designation B-26C) Aircraft, Including Those Certificated Under Part 8 of the Civil Air Regulations. Compliance required as indicated. (a) To protect against failure of the wing rear spar caps in the vicinity of the flap inboard hinges, conduct the following inspection within 250 hours' time in service after the effective date of this AD, unless already accomplished within the last 250 hours' time in service and thereafter within 500 hours' time in service from the last inspection: (1) Inspect the rear upper and lower spar caps, left and right wings, by means of visual and dye penetrant methods for cracks in the inboard flap hinge point bolts holes, the 1 3/4 inch diameter spotfaces, and the area surrounding the holes, 8 3/4 inches outboard of the wing-to-fuselage attach points. Pay particular attention to the bolt holes and edges of the holes. Remove any nonflexible type wing fuel cells installed at this location to permit accomplishment of this inspection. (2) To protect against failure of the wing rear spar lower caps in the vicinity of the inboard end of the fore and aft flanges and the forward flange 3/8 inch bolt hole, conduct the following inspection within 50 hours' time in service after the effective date of this amendment, unless already accomplished within the last 450 hours' time in service and thereafter at the same 500 hour interval specified in Paragraph (a), above. Remove the wing-to-fuselage fillets, left and right bottom, to gain access to the spar cap assemblies. Remove paint and thoroughly clean the cap fore and aft flanges from the inboard flap hinge points inboard to the flange end radius. Conduct a penetrant inspection of the flanges in that area for cracks, paying particularattention to the 3/8 inch bolt hole in the forward flange where the lower skin attaches, and the flange end radii. If no cracks are found, apply one coat of primer to the area from which the paint was removed. (3) Any rear spar upper or lower cap showing evidence of a crack shall be replaced with a new part or be repaired or reworked in a manner approved by the Chief, Aircraft Engineering Division, FAA Western Region, before further flight. (b) To protect against failure of the front spar lower caps in the vicinity of Wing Station 140, conduct inspections in accordance with paragraph (b)(4) at the following intervals: (1) For aircraft with less than 500 hours military flight time regardless of the amount of civil hours' time in service unless accomplished within the last 250 hours' time in service inspect within 250 hours' time in service after the effective date of this AD and thereafter within 500 hours' time in service from the last inspection. (2) For aircraft with from 500 to 2,000 hours military flight time unless accomplished within the last 375 hours' time in service, inspect within the next 125 hours' time in service after the effective date of this AD, and thereafter within 500 hours' time in service from the last inspection. (3) For aircraft with more than 2,000 hours military flight time and for all aircraft on which the military flight time cannot be clearly established, unless already accomplished within the past 235 hours' time in service, inspect within the next 15 hours' time in service after the effective date of this AD, and thereafter within 250 hours' time in service from the last inspection. (4) At the time specified in (b)(1), (2) or (3), inspect the front spar lower cap in accordance with one of the following: (i) Remove the front spar fitting, P/N 4190305, and the nacelle fitting, P/N 4123165 at approximately Wing Station 140 left and right. Support the wings so as to remove all airplane weight from the landing gear, remove or properly support the engines and remove the oil tanks and adjacent fuel tanks to permit the removal of these fittings. By means of visual and dye penetrant methods, inspect for the evidence of any crack at the edges of the three large holes (nominal 1/2-inch diameter) in each front spar lower cap or adjacent to the edges of those holes. (ii) Remove the three tension bolts (nominal 7/16-inch diameter) which pass through each front spar lower cap at approximately Wing Station 140 and front spar fitting, P/N 4190305, and nacelle attach fitting, P/N 4123165. Support the wings so as to remove all weight from the landing gear, remove or support the engines and remove the oil tanks. Thoroughly inspect the inner surface of each bolt hole by eddy current technique using the equipment and following the procedures described by Magnaflux Corporation Bulletin No. LA-002-RBW, "Operating Instructions for Magnatest ED-600" dated April 23, 1964, or Magnaflux Corporation Specification LA-RAE-7170, "Operating Instructions for Magnatest ED-520 for Bolt Hole Inspection," dated August 6, 1971. The changes in meter readings as described in Bulletin No. LA-002-RBW or in Specification LA-RAE-7170 shall be used to detect any evidence of cracking in any of the bolt holes, with particular attention being directed to both edges of each hole. NOTE: Information regarding this bulletin and eddy current equipment is available from any local office of the Magnaflux Corporation. (iii) Use radiographic inspection methods accomplished in a manner approved by the Chief, Aircraft Engineering Division, FAA Western Region. Such approval requires submittal of performance standards and technical qualifications which have been based upon positive proof of the ability to detect any crack in or immediately adjacent to the three large holes through the front spar lower cap. (5) Any spar cap showing evidence of a crack shall be replaced with anew part or be repaired or reworked in a manner approved by the Chief, Aircraft Engineering Division, FAA Western Region, before further flight unless supplemental and more extensive inspections show that a crack does not exist. (c) The repetitive inspections of the rear spar caps required by (a) may be discontinued when they have been modified in accordance with the technical data approved by the Chief, Aircraft Engineering Division, FAA Western Region. (d) The repetitive inspections of the lower front spar caps required by (b) may be discontinued when they have been modified in accordance with the technical data approved by the Chief, Aircraft Engineering Division, FAA Western Region. (e) The inspections required in (a) and (b) need not be conducted on any aircraft certificated in the restricted category if the operating limitations for such aircraft are revised to add limitations prohibiting operation: (1) At a takeoff weight in excess of 30,000 pounds.(2) At speeds in excess of 250 m.p.h. IAS. (3) Over any congested area of a city, town or settlement, or over any open air assembly of persons. (f) The operating limitations specified in (e) may be discontinued when both the rear spar caps and the lower front spar caps have been modified in accordance with the technical data approved by the Chief, Aircraft Engineering Division, FAA Western Region. NOTE: Approved modifications are described by: (1) Technical data listed in STC No. SA692WE, revised July 1, 1964, issued to the On Mark Engineering Company, Van Nuys, California. (2) Technical data listed in STC No. SA1107WE, dated November 24, 1965, issued to the Rock Island Oil Refining Company, Hutchinson, Kansas. Amendment 741 Part 507 Federal Register June 3, 1964 supersedes AD 64-9-4. Amendment 741 Part 507 Federal Register June 3, 1964 become effective June 3, 1964. Revised July 8, 1964. Revised August 5, 1964. Revised February 12, 1965. Amendment 39-1291 became effective September 21, 1971. Amendment 39-1360 became effective December 21, 1971. This amendment 39-2258 becomes effective July 15, 1975.
97-06-01: This amendment adopts a new airworthiness directive (AD), applicable to CFM International CFM56-5, -5B, and -5C series turbofan engines, that requires initial and repetitive borescope inspections of the stage 1 disk bore of certain high pressure compressor rotor (HPCR) stage 1-2 spools for rubs and scratches, and replacement, if found rubbed or scratched, with a serviceable part. This AD also requires removal and replacement of certain stationary number 3 bearing aft air/oil seals as terminating action to the inspection program. This amendment is prompted by a report of an engine found with a rub on the forward corner of the HPCR stage 1 disk bore due to contact with the stationary number 3 bearing aft air/oil seal. The actions specified by this AD are intended to prevent a failure of the stage 1 disk of the HPCR stage 1-2 spool, which could result in an uncontained engine failure and damage to the aircraft.
64-14-03: 64-14-03 DORNIER: Amdt. 746 Part 507 Federal Register June 13, 1964. Applies to All Model DO-28 Aircraft Up to and Including Serial Number 3060. Compliance required as indicated. It has been found that the generator and battery relays remain inoperative with low battery voltage so that the electrical system remains without power supply. To correct this condition, accomplish the following: Within the next 50 hours' time in service, change the electrical wiring as specified by Dornier Technical Bulletin 28-6 dated December 7, 1962. (Dornier Technical Bulletin No. 28-6 dated December 7, 1962 covers this same subject.) This directive effective July 13, 1964.
2002-26-22: This amendment adopts a new airworthiness directive (AD), applicable to certain Raytheon Model Hawker 800XP airplanes, that requires installing jumper wires on the computer control switches to power the digital electronic engine control when overspeed protection is selected, and tying and stowing the jumper wires on the switches. The actions specified by this AD are intended to prevent loss of the overspeed protection function without the flightcrew's awareness, due to missing jumper wires, which could result in engine overspeed and possible uncommanded engine shutdown. This action is intended to address the identified unsafe condition.
97-06-16: This amendment adopts a new airworthiness directive (AD) that is applicable to McCauley Propeller Systems 1A103/TCM series propellers. This action supersedes priority letter AD 95-21-01 that currently requires visual inspections for cracks in the propeller hub of certain propellers using a 10X power magnifying-glass. This action requires an initial inspection for cracks in the propeller hub in accordance with a dye penetrant inspection procedure, replacement of propellers with cracks that do not meet acceptable limits, rework of propellers with cracks that meet acceptable limits, and repetitive inspections of all affected propellers. This amendment is prompted by development of a dye penetrant inspection and rework procedures. The actions specified by this AD are intended to prevent propeller separation due to hub fatigue cracking, which can result in loss of control of the aircraft.
99-26-15: This amendment adopts a new airworthiness directive (AD), applicable to certain Airbus Model A300 B2 and B4 series airplanes, that requires repetitive inspections to detect cracking of the inner skin panel of the longitudinal lap joint; and repair, or modification and new repetitive inspections, if necessary. 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 detect and correct stress corrosion cracking of the inner skin panel of the longitudinal lap joint, which could result in rapid depressurization of the airplane.
2011-14-03: We are adopting a new airworthiness directive (AD) for the products listed above. This AD requires repetitive inspections for cracking of the left and right upper center skin panels of the horizontal stabilizer, and corrective action if necessary. This AD was prompted by a report of a crack found in the upper center skin panel at the aft inboard corner of a right horizontal stabilizer. We are issuing this AD to detect and correct cracks in the horizontal stabilizer upper center skin panel. Uncorrected cracks might ultimately lead to the loss of overall structural integrity of the horizontal stabilizer.
97-06-15: 97-06-15 General Electric Company: Amendment 39-9972. Docket 95-ANE-41. Applicability: General Electric Company (GE) Models CF34-1A, -3A, and -3A2 turbofan engines, with high pressure compressor (HPC) stage 1 rotor disks, part number 6040T79G01, installed. These engines are installed on but not limited to Canadair Limited Model CL-600-2A12 and CL-600-2B16 aircraft. Note 1: This airworthiness directive (AD) applies to each engine 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 engines 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 prevent HPC stage 1 rotor disk rupture, engine failure, and damage to the aircraft, accomplish the following: (a) Remove from service HPC stage 1 rotor disks prior to accumulating 6,000 cycles in service since new, and replace with a serviceable part. (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, Engine Certification Office. The request should be forwarded through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Engine Certification Office. Note 2: Information concerning the existence of approved alternative methods of compliance with this airworthiness directive, if any, may be obtained from the Engine Certification Office. (c) This amendment becomes effective on May 27, 1997.
2002-26-14: This amendment adopts a new airworthiness directive (AD) that is applicable to all Boeing Model 767-300 series airplanes modified by supplemental type certificate ST01869AT-D. This action requires modifying the passenger entertainment system (PES) and revising the airplane flight manual. This action is necessary to ensure that the airplane crew is able to remove electrical power from the PES when necessary and is advised of appropriate procedures for such action. Inability to remove power from the PES during a non-normal or emergency situation could result in inability to control smoke or fumes in the airplane flight deck or cabin. This action is intended to address the identified unsafe condition.
2018-03-02: We are adopting a new airworthiness directive (AD) for certain 328 Support Services GmbH Model 328-300 airplanes. This AD requires contacting the FAA to obtain instructions for addressing the unsafe condition on these products, and doing the actions specified in those instructions. This AD was prompted by a determination that incomplete inspection instructions exist for the skin under outer and inner doublers left installed after the removal of a certain data link system. We are issuing this AD to address the unsafe condition on these products.
47-07-05: 47-07-05 FAIRCHILD: (Was Mandatory Note 7 of AD-724-2.) Applies to M-62 Series Aircraft. Compliance required at next periodic inspection. In order to eliminate the possibility of foreign objects entering the torque tube, install a boot at the point where the elevator control enters the torque tube in the front cockpit, and where the control stick enters the torque tube bracket in the rear cockpit. Also install cover plates on the sides of the torque tube bracket in the rear cockpit. (Fairchild Service Bulletin 44-62-5 dated October 10, 1944, covers this same subject.)
2002-26-20: This amendment adopts a new airworthiness directive (AD), applicable to certain McDonnell Douglas Model DC-9-81 (MD-81), DC-9-82 (MD-82), and DC-9-83 (MD-83) airplanes, and Model MD-88 airplanes, that requires an inspection of the disconnect panel area above the aft left lavatory for chafed or damaged wires or unacceptable clearance between the wires and adjacent structure, and corrective actions, if necessary. The actions specified by this AD are intended to prevent chafing of wires at the disconnect panel above the aft left lavatory, which could result in electrical arcing, and consequent fire in the cabin. This action is intended to address the identified unsafe condition.
2002-26-21: This amendment adopts a new airworthiness directive (AD), applicable to certain Dornier Model 328-100 and -300 series airplanes, that requires inspecting the electrical wire harness next to the fuel line at the left electric fuel pump for signs of chafing; securing the electrical wire harness to the fuel line using ty-rap; and taking corrective actions, if necessary. This action is necessary to prevent damage to the electrical wire harness, which could result in electrical arcing and an increased potential for fire or explosion. This action is intended to address the identified unsafe condition.
2011-13-03: We are adopting a new airworthiness directive (AD) for the products listed above. This AD requires inspecting certain Lycoming and TCM reciprocating engines with certain Hartzell Engine Technologies, LLC (HET) turbochargers installed, and disassembly and cleaning of the turbocharger center housing and rotating assembly (CHRA) cavities of affected turbochargers. This AD was prompted by a turbocharger failure due to machining debris left in the cavities of the CHRA during manufacture. We are issuing this AD to prevent seizure of the turbocharger turbine, which could result in damage to the engine, and smoke in the airplane cabin.
99-25-15: This amendment supersedes an existing airworthiness directive (AD), applicable to certain Airbus Model A300, A310, A300-600 series airplanes, that currently requires a one-time operational test and repetitive functional tests of the free fall control mechanism of the landing gear to ensure proper release of the main landing gear (MLG), and corrective action, if necessary. It also requires eventual modification of the free fall control mechanism of the landing gear, which constitutes terminating action for the repetitive functional tests. This amendment requires, for certain airplanes, that the modification of the free fall control mechanism of the landing gear be accomplished in accordance with a corrected version of the manufacturer s service bulletin. 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 malfunction of the free fall control mechanism of the landing gear, which could result in the inability to extend the MLG in the event of failure of the hydraulic extension system.
93-07-07: 93-07-07 FOKKER: Amendment 39-8539. Docket 92-NM-178-AD. Applicability: Model F28 Mark 0100 series airplanes; serial numbers 11244 through 11339, inclusive, and 11341 through 11351, inclusive; certificated in any category. Compliance: Required as indicated, unless accomplished previously. To prevent fuel leakage in the rear fuselage, accomplish the following: (a) Within 6 months after the effective date of this AD, conduct an inspection of the auxiliary power unit (APU) fuel supply tube assembly to determine minimum clearance between the tube assembly and the aircraft structure, in accordance with Fokker Service Bulletin SBF100-28-022, dated December 13, 1991. (1) If the APU fuel supply tube assembly is chafed or if it touches the aircraft structure, prior to further flight, replace the APU fuel supply tube assembly with a new assembly, in accordance with the service bulletin. (2) If the clearance is less than 3 mm at any point, but the APU fuel supply tube assembly is not chafed and does not touch the aircraft structure: Within 3 months after accomplishing the inspection, replace the APU fuel supply tube assembly with a new assembly, in accordance with the service bulletin. (3) If the clearance is 3 mm or more at all points, no further action is necessary. (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 Maintenance Inspector, who may add comments and then send it to the Manager, Standardization Branch, ANM-113. NOTE: 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 FAR 21.197 and 21.199 to operate the airplane to a location where the requirements of this AD can be accomplished. (d) The inspection and replacement shall be done in accordance with Fokker Service Bulletin SBF100-28-022, dated December 13, 1991. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR Part 51. Copies may be obtained from Fokker Aircraft USA, Inc., 1199 North Fairfax Street, Alexandria, Virginia 22314. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. (e) This amendment becomes effective on June 1, 1993.