Results
2005-25-24: The FAA is adopting a new airworthiness directive (AD) for certain Boeing Model 777-200 and -300 series airplanes. This AD requires repetitive detailed inspections of the forward lugs of the power control unit (PCU), yoke assembly, and forward attachment hardware of the left inboard, left outboard, right inboard, and right outboard flaperon PCUs; and other specified/corrective actions if necessary. For certain airplanes, this AD also requires other related concurrent actions. This AD results from reports indicating that operators have found worn, fretted, and fractured bolts that attach the yoke assembly to the flaperon PCU. We are issuing this AD to prevent damage and eventual fracture of the yoke assembly, pin assembly, and attachment bolts that connect the inboard and outboard PCUs to a flaperon, which could lead to the flaperon becoming unrestrained and consequently departing from the airplane. Loss of a flaperon could result in asymmetric lift and reduced roll control ofan airplane. A departing flaperon could also cause damage to the horizontal and vertical stabilizers, which could result in loss of control of the airplane if damage is significant.
98-26-11: This amendment adopts a new airworthiness directive (AD), applicable to certain Saab Model SAAB 2000 series airplanes, that requires replacement of the end-pieces of the expansion chamber attenuator (ECA) for the standby pump of the Number 2 hydraulic system with new, improved end-pieces. 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 leakage of hydraulic fluid from the Number 2 hydraulic system due to failure of the end-pieces of the ECA, which could result in loss of nose wheel steering, flap operation, normal landing gear operation, and reduced redundancy in the brake and flight controls systems.
80-02-17: 80-02-17 CESSNA: Amendment 39-3675. Applies to Model 441 (S/Ns 441-0001 thru 441-0106 and 441-0109 airplanes). COMPLIANCE: Required as indicated unless already accomplished. To preclude accidents resulting from the inability of the airplane to meet flight manual performance data, prior to further flight accomplish either paragraph A) or B) below: A) Install Revision 5 dated March 26, 1979, in the Pilot's Operating Handbook and FAA Approved Airplane Flight Manual and operate the airplane in accordance with this revision. (This action was required by AD 79-10-08 on S/Ns 441-0001 through 441-0097 airplanes and incorporated in Airplanes S/Ns 441-0098 through 441-0106 and S/N 441-0109 by the manufacturer.) NOTE: This does not prohibit incorporation of later nonconflicting revisions in the Pilot's Operating Handbook and FAA Approved Airplane Flight Manual. B) If the engines are equipped with AiResearch P/N 897110-8 fuel control assemblies, modify the airplaneand Pilot's Operating Handbook and FAA Approved Airplane Flight Manual in accordance with the following: 1) Adjust the Engine Fuel Controls and Computers in accordance with Garrett AiResearch Service Bulletin TPE 331-73-0093 and Cessna Customer Care Service Information Letter PJ 80-1. 2) Install a two-sided reversible instrument panel placard in accordance with Cessna Service Kit SK 441-28 and operate the airplane in accordance with this placard. 3) Perform an overspeed governor check in accordance with Cessna Service Kit SK 441-28. 4) Install Revision 8 in the Pilot's Operating Handbook and FAA Approved Flight Manual and operate the airplane in accordance with this revision. C) The airplane may be flown to a location where paragraphs A) or B) can be accomplished, provided it is not operated with aviation gasoline fuel, grades 80/87 or 100LL. D) Any equivalent method of compliance with this AD must be approved by the Chief, Engineering & ManufacturingDistrict Office No. 43, Federal Aviation Administration, Room 220, Mid-Continent Airport, Wichita, Kansas 67209. Telephone (316) 942-4285. Cessna Propjet Customer Care Service Information Letters PJ 79-8 dated April 2, 1979, and PJ 80-1 dated January 11, 1980, including Garrett AiResearch Service Bulletin TPE 331-73-0093, cover the subject matter of this AD. The AD supersedes AD 79-10-08, Amendment 39-3470 (44 FR 27977). This amendment becomes effective January 29, 1980.
2005-25-26: The FAA is adopting a new airworthiness directive (AD) for certain Boeing Model 747-400, 747-400D, and 747-400F series airplanes. This AD requires repetitive detailed inspections for damage (degraded finish; missing, lifted, peeling, or blistering paint; or signs of corrosion) of the interior skin in the forward and aft cargo compartments, and corrective actions if necessary. This AD results from reports of skin corrosion on four Boeing Model 747 series airplanes that were delivered between 1995 and 1999. We are issuing this AD to detect and correct corrosion, which can penetrate the thickness of the skin and cause cracking, and result in rapid decompression of the airplane.
2018-26-08: We are adopting a new airworthiness directive (AD) for certain Airbus SAS Model A320-214, A320-232, A320-233, A321-211 and A321-231 airplanes. This AD was prompted by an investigation that revealed that the outer cylinder of a certain ram air turbine (RAT) actuator was not properly deburred in accordance with manufacturing specifications. This AD requires a replacement of affected RAT actuators. We are issuing this AD to address the unsafe condition on these products.
98-26-04: This amendment supersedes an existing airworthiness directive (AD), applicable to certain Boeing Model 757 series airplanes, that currently requires an inspection of the engine fuel shutoff valves (spar valves) to detect leakage of fuel and to ensure that no leakage occurs when the valves are commanded to close. That amendment also requires an alignment procedure of the engine fuel shutoff valves, if necessary. This amendment expands the applicability of the existing AD. This amendment is prompted by additional reports that certain crossfeed valve assemblies and engine shutoff valve assemblies were improperly installed during manufacturing of the airplane. The actions specified in this AD are intended to prevent uncommanded fuel flow from the fuel tanks to the engine nacelle, which could result in reduced airplane fire protection in the event of a leak in the engine fuel line or a fire in the engine nacelle.
86-22-06: 86-22-06 CESSNA: Amendment 39-5453. Applies to Models 208 and 208A (Serial Numbers 20800001 thru 20800105) airplanes certificated in any category. Compliance: Required by December 31, 1986, unless already accomplished. To prevent fuel starvation during takeoff due to improper positioning of the wing fuel tank selectors, accomplish the following: (a) For Models 208 and 208A (Serial Numbers 20800001 through 20800105) airplanes, install the Cessna fuel selector warning system, revise the POH/AFM, and perform all required system checks, as described in Cessna Bulletin CAB86-8 dated October 10, 1986. (b) For Models 208 and 208A (Serial Numbers 20800001 through 20800083) airplanes, modify the low fuel level transmitter supports as described in Cessna Bulletin CAB 86- 26, dated September 5, 1986. (c) Airplanes may be flown in accordance with FAR 21.197 to a location where this AD may be accomplished. (d) An equivalent method of compliance with this AD may be approved by the Manager, Aircraft Certification Office, FAA, 1801 Airport Road, Room 100, Mid-Continent Airport, Wichita, Kansas 67209. All persons affected by this AD may obtain copies of the documents referred to herein upon request to Cessna Aircraft Company, Customer Services, Post Office Box 1521, Wichita, Kansas 67201; or FAA, Office of the Regional Counsel, Room 1558, 601 East 12th Street, Kansas City, Missouri 64106. This action supersedes AD 86-09-08, Amendment 39-5308, published May 12, 1986 (51 FR 17322) and withdraws NPRM Docket Number 86-CE-13-AD published June 5, 1986 (51 FR 20495). This amendment becomes effective on November 7, 1986.
2005-26-03: The FAA is adopting a new airworthiness directive (AD) for certain Boeing Model 737 airplanes. This AD requires modifying the elevator input torque tube assembly. This AD results from a report of a restriction in the pilot's elevator input control system. A design review performed on the elevator input torque tube assembly in the course of the investigation discovered possible failure modes that could lead to a jam of the elevator control system. We are issuing this AD to prevent loss of elevator control and consequent reduced controllability of the airplane.
2019-10-03: We are adopting a new airworthiness directive (AD) for all The Boeing Company Model 737-100, -200, -200C, -300, -400, and -500 series airplanes. This AD was prompted by reports of cracks caused by corrosion of the edge of the bore of the spot face and corrosion of the lug bore of certain side-strut support fitting lugs. This AD requires repetitive detailed inspections of the left and right side-strut support fitting lugs with bushings installed for any corrosion, any crack, or any severed lug; repetitive detailed and high frequency eddy current (HFEC) inspections of the left and right side-strut support fitting lugs with bushings removed for any corrosion or any crack; and applicable on-condition actions. We are issuing this AD to address the unsafe condition on these products.
98-24-33: This amendment adopts a new airworthiness directive (AD), applicable to certain McDonnell Douglas Model DC-9 and DC-9-80 series airplanes, Model MD-88 airplanes, and C-9 (military) series airplanes, that requires a one-time visual inspection to detect fatigue cracking of the lower left nose of certain longerons and the attaching frames; repair, if necessary; and installation of a preventive modification. This amendment is prompted by several reports of fatigue cracking of certain longerons and the attaching frames. The actions specified by this AD are intended to prevent such fatigue cracking, which could result in reduced structural integrity of the fuselage, and consequent loss of pressurization of the airplane.
82-25-02: 82-25-02 AVIONS MARCEL DASSAULT - BREGUET AVIATION: Amendment 39-4502. Applies to all AMD-BA Falcon 10 airplanes certificated in all categories. Compliance is required within the next 250 hours time in service or 90 days, whichever occurs first, after the effective date of this AD, unless already accomplished. 1. To prevent the potential failure of the landing gear to extend or retract, inspect and modify or replace, if necessary, (a) the pilot valve ball pushrod; (b) the selector solenoid valve; and (c) the spring in the landing gear control selector solenoid valve assembly in accordance with the Accomplishment Instructions of Avions Marcel Dassault-Breguet Aviation Service Bulletin Nos. F10-0149, Revision 1, dated November 22, 1978; F10-0168, Revision 1, dated February 8, 1979; F10-0173 dated November 22, 1978; and F10-0174 dated November 22, 1978. 2. Alternate means of compliance which provide an equivalent level of safety may be used when approved by the Manager, Seattle Aircraft Certification Office, FAA, Northwest Mountain Region. 3. 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/or modifications required by this AD. The manufacturer's specifications and procedures identified and described in this directive are incorporated herein and made a part hereof pursuant to 5 U.S.C. 552(a)(1). This amendment becomes effective December 6, 1982.
2005-25-21: The FAA is adopting a new airworthiness directive (AD) for certain Airbus Model A330-243, -341, -342, and -343 airplanes equipped with Rolls-Royce RB211 TRENT 700 engines. This AD requires modifying the cowl assemblies of the left- and right-hand thrust reversers. This AD results from a review of certification tests of the thrust reverser, which revealed that certain structural components within the C-duct need strengthening to meet high fatigue loads and maintain structural integrity. We are issuing this AD to prevent fatigue cracking of the hinges integrated into the 12 o'clock beam of the thrust reversers, which could result in separation of a thrust reverser from the airplane, and consequent reduced controllability of the airplane.
2011-17-03: 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: [T]he Federal Aviation Administration (FAA) has published Special Federal Aviation Regulation (SFAR) 88, and the Joint Aviation Authorities (JAA) has published Interim Policy INT/POL/25/ 12. The review conducted by Fokker Services on the Fokker F28 Type Design in response to these regulations revealed that, under certain failure conditions, a short circuit may develop in the collector tank level float switch wiring. Such a short circuit may result in an ignition source in the tank vapour space. This condition, if not corrected, could result in a wing fuel tank explosion and consequent loss of the aeroplane. * * * * * We are issuing this ADto require actions to correct the unsafe condition on these products.
98-24-24: This amendment adopts a new airworthiness directive (AD), applicable to certain MD-11 series airplanes, that requires a one-time visual inspection to detect discrepancies of the seat tracks and adjacent structure underneath lavatories, and repair, if necessary. This amendment also requires installation of a non-metallic barrier on the bottom of each lavatory foot fitting, and replacement of existing seat track fittings with new seat track fittings. This amendment is prompted by reports of galvanic corrosion found on the seat tracks at attachment points under certain lavatories. The actions specified by this AD are intended to prevent corrosion of seat tracks and adjacent structure. Corrosion of the seat tracks and adjacent structure could result in shifting of lavatories, which could lead to injury of passengers and crew, as well as damage to aircraft structure and systems.
60-24-04: 60-24-04 SIKORSKY: Amdt. 221 Part 507 Federal Register November 11, 1960. Applies to All S-58 Helicopters. Compliance required within the next 50 hours' time in service after effective date. Complete loss of electrical power and excessive battery fumes have resulted from the breakage of the cable connected to the L(plus) terminal of Eclipse Pioneer Voltage Regulator P/N 1597-1. In order to preclude the breakage of the L(plus) cable and the resulting loss of electrical power, the following is required unless already accomplished: (a) Remove the existing clamp securing the voltage regulator cables to the airframe at a distance of approximately 12 inches from the regulator base. (b) Install cable clamp MS 21919DG5, or equivalent, to secure the regulator cables to the regulator base utilizing an existing hole in the corner of the regulator base. This should be accomplished while providing enough cable slack to relieve tension on the terminal lugs but without changing the cable routing. (c) If, in some installations, there is an unduly long length of unsupported cable existing beyond the voltage regulator after compliance with (a) and (b), an additional clamp of the same type should be provided to attach the cable to the airframe with care being exercised so that the motion of the regulator on its shockmount is not restricted. (Sikorsky Service Bulletin No. 58B55-1 covers this same subject.) This directive effective November 28, 1960.
84-03-51: 84-03-51 BOEING VERTOL COMPANY: Amendment 39-4823. Applies to Boeing Vertol Model 234 series helicopters certificated in all categories. Compliance is required as indicated. To prevent possible hazards in flight associated with cracking of the main rotor head tie bars, accomplish the following: (a) Unless already accomplished, within the next 25 hours time in service from the effective date of this AD or before the accumulation of 450 hours time in service, whichever comes later, and thereafter as specified in paragraphs (c) and (d) of this AD, visually inspect for cracks in the forward main rotor tie bars P/N 114R21551 with serial numbers A13207 and below. If the letter "B" is shown after the serial number, this AD does not apply. (b) Unless already accomplished, within the next 25 hours time in service from the effective date of this AD or before the accumulation of 550 hours time in service, whichever comes later, and thereafter as specified in paragraphs (c) and (d) of this AD, visually inspect for cracks in the aft main rotor tie bars P/N 114R21551 with serial numbers A13207 and below. If the letter "B" is shown after the serial number, this AD does not apply. (c) After the initial inspections in paragraphs (a) and (b) or the inspections in paragraph (d), repeat visual inspections of tie bars at intervals not to exceed 450 hours time in service for tie bars in paragraph (a) and 550 hours time in service for paragraph (b). (d) Whenever a main rotor head is disassembled to inspect or replace the hub, horizontal hinge pin, or pitch shaft, conduct the inspection of tie bars specified in paragraph (a) or (b). (e) Remove from service tie bars having a crack and replace with a serviceable part prior to further flight. (f) An equivalent method of compliance with this AD may be used when approved by the Manager, New York Aircraft Certification Office, 181 South Franklin Avenue, Valley Stream, New York 11581. (g) In accordance with FAR 21.197, flight is permitted to a base where the requirements of this AD may be accomplished. This amendment becomes effective March 14, 1984, as to all persons except those persons to whom it was made immediately effective by telegraphic AD No. T84-03-51 issued January 27, 1984, which contained the amendment.
2005-25-16: The FAA is adopting a new airworthiness directive (AD) for certain EMBRAER Model ERJ 170 airplanes. This AD requires doing a general visual inspection of the passenger seat track attachments to determine if the attachment rod is installed and to check the torque value of the attachment bolts, and doing any corrective actions if necessary. This AD results from the finding of missing rods, which attach the passenger seat tracks to the airplane structure to absorb loads. We are issuing this AD to detect and correct missing attachment rods, which could result in reducing the ability of the seat to withstand a hard landing or rejected takeoff and possible injury to passengers.
98-24-26: This amendment adopts a new airworthiness directive (AD), applicable to certain Boeing Model 747-400 series airplanes, that requires replacing the cam assembly, cam bellcrank assembly, and thrust reverser control switch actuator on all four thrust levers with new components. This amendment is prompted by a report of an uncommanded automatic retraction of the leading edge flaps during takeoff. The actions specified by this AD are intended to prevent such uncommanded automatic retraction, which would seriously degrade liftoff and climb capabilities, and could result in near-stall conditions at a critical phase of the flight.
60-04-04: 60-04-04 LOCKHEED: Amdt. 101 Part 507 Federal Register February 13, 1960. Applies to All Models 049, 149, 649 and 749 Series Aircraft Which Have the Cleveland Pneumatic Model 8298 Series Main Landing Gear Struts Installed With the Removable Side Brace Attachment Collar. Compliance required as indicated. Due to fatigue failures found in the above main landing gear outer cylinder, the following inspections and rework must be accomplished on all main landing gears which have accumulated 25,000 or more hours' time in service. (a) Unless already accomplished in the last 1,000 hours' time in service, within 400 hours' time in service inspect for cracks in the main landing gear outer cylinder surface, at the 0.125-inch radius of the shoulder against which the drag strut-side brace collar retaining nut bears, by means of one of the three methods in (b). Reinspect every 1,000 hours' time in service thereafter, until the rework in (c)(2) is accomplished. Outer cylinders with cracks must be replaced prior to further flight. Cracked cylinders may be returned to service after repair and rework is accomplished in accordance with (c). Rework on all uncracked outer cylinders must be accomplished in accordance with (c)(2) not later than the total accumulated hours' time in service indicated in (b). (b) Inspection and rework: (1) ULTRASONIC SHEAR WAVE DETECTION METHOD. This procedure may be used on cylinders with piston and oil in the cylinder or the cylinder only. Rework in accordance with (c)(2) must be accomplished within 4,000 hours' time in service if the ultrasonic method is used. (2) MAGNETIC PARTICLE DETECTION METHOD. This method requires removing and dismantling of the strut assembly. Rework in accordance with (c)(2) must be accomplished within 4,000 hours' time in service if the magnetic particle method is used. (3) RADIOGRAPHIC METHOD. This method requires the removal of the piston from the cylinder and complete 360 degree coverage. Reworkin accordance with (c)(2) must be accomplished within 3,000 hours' time in service if the radiographic method is employed. (c) Repair and rework instructions: (1) Outer cylinders with cracks in the radius described in (a) and for a distance of 0.5 inch below the radius tangency point circumferentially around the cylinder may be repaired by grinding out to a maximum depth of 0.017 inch. Complete removal of cracks must be verified by magnetic particle inspection or equivalent. If cracks are completely removed as verified by such inspection, remove an additional 0.008 inch of material from the repaired area. Rework may be acceptable on outer cylinders with cracks that cannot be removed by grinding to a depth of 0.017 inch. Such cases may be submitted to the FAA for evaluation of the extent of cracking and to determine if rework is possible. Rework accomplished subsequent to such an evaluation must be in accordance with FAA approved repair instructions. (2) On all cylinders,whether cracks are found or not, rework the area described in (c)(1) as follows: (i) Clean and polish the above cylinder area to remove all tool marks and corrosion. (ii) Shotpeen the above area using steel shot 0.019-0.033-inch diameter to an intensity of 0.012-0.016 A(subscript 2) ALEMENT (Reference LAC Process Bulletin 217M, Revision 1). (d) Upon completion of the rework described in (c)(2), all Model 8298 cylinders shall be reinspected for cracks at periods not to exceed 9,000 hours' time in service using one of the inspection methods noted in (b). Cracked cylinders must be replaced prior to further flight. Cracked cylinders may be returned to service after repair and rework is accomplished in accordance with (c). (Lockheed Service Letter FS/239304 covers this same subject.) Revised April 9, 1960. Revised September 15, 1960.
62-20-02: 62-20-02 GENERAL DYNAMICS/CONVAIR: Amdt. 482 Part 507 Federal Register September 8, 1962. Applies to All Models 22, 22M and 30 Series Aircraft. Compliance required within the next 350 hours' time in service from the effective date of this AD, unless already accomplished. To prevent the aileron override spring from jamming in the compressed position if full opposition loads are applied to the lateral control system, the aileron override spring assembly shall be modified to incorporate a stop in accordance with General Dynamics/Convair Service Bulletins A27-56, A27-25, or A27-26 for the Models 22, 22M or 30, respectively, or in accordance with an FAA engineering approved equivalent. (General Dynamics/Convair Alert Service Bulletin A27-56 for the Model 22, A27-25 for the Model 22M, and A27-26 for the Model 30 cover this same subject.) This directive effective October 9, 1962.
61-14-03: 61-14-03 CONVAIR: Amdt. 301 Part 507 Federal Register July 7, 1961. Applies to All Model 22 (880) Aircraft Having Cartridge Assembly-Rudder Spring P/N 22-46223 Installed. Compliance required as indicated. One instance has occurred on the Model 22 (880) aircraft in which the cartridge assembly-rudder spring P/N 22-46223 seized due to corrosion and galling, resulting in limited rudder travel. The effects of this malfunction upon operational safety are such as to require accomplishment of the following: (a) Within the next 100 hours' time in service unless already accomplished in the last 220 hours' time in service, and at each 320 hours' time in service thereafter, conduct the following operational check: Lock the rudder flight tab and rudder in neutral position and operate the rudder pedals right and left until the cockpit stops are contacted 5 or more times. If any roughness in operation is noted, remove cartridge assembly-rudder spring P/N 22-46223, and replace with aP/N 22-46223 which has been inspected and found free of corrosion or galling and operationally checked, or a part reworked in accordance with the provisions of Convair Service Bulletin No. 27-33 and reidentified as P/N 22-46223-1, prior to further flight. (b) When the cartridge assembly-rudder spring is replaced with an assembly reworked in accordance with provisions of Convair Service Bulletin 27-33 and reidentified as P/N 22-46223-1, the inspection specified in (a) may be discontinued. (Convair Service Bulletin No. 27-33 covers this same subject.) This directive effective July 7, 1961.
98-24-04: This amendment adopts a new airworthiness directive (AD) that applies to certain SOCATA - Groupe AEROSPATIALE (SOCATA) Model TBM 700 airplanes. This AD requires repetitively inspecting (using visual methods) the web of the left and right flap carriage for cracks, and replacing any cracked flap carriage with one of improved design. The proposed AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for France. The actions specified by this AD are intended to detect and correct cracks in a flap carriage, which could result in loss of the flap function with consequent reduced and/or loss of airplane control.
83-07-06: 83-07-06 BOEING VERTOL COMPANY AND KAWASAKI HEAVY INDUSTRIES, LTD.: Amendment 39-4600. Applies to Boeing Vertol Model 107-II and Kawasaki Model KV107-II and KV107-IIA helicopters certificated in all categories equipped with No. 5 Synchronizing Shaft, P/N 107D3340-1 or 107D3140-1. Compliance is required as indicated on all No. 5 Synchronizing Shaft Assemblies P/N 107D3340-1 or 107D3140-1 with 1200 hours' or more total time in service. To prevent failure of the steel synchronizing shaft due to improperly drilled rivet holes, accomplish the following: A. Within 50 hours' time in service after the effective date of this AD (unless already accomplished within the past 250 hours' time in service) and every 300 hours' time in service thereafter, visually inspect the interior and exterior surfaces of the No. 5 Synchronizing Shaft Assembly P/N 107D3340-1 or 107D3140-1 for cracks, damage or defects in the area adjacent to the adapter-to-tube rivets at both ends, particularly at the inboard row of rivets. The visual inspection shall be either a lighted borescope inspection using at least 2X magnification or dye penetrant inspection methods combined with at least 2X visual magnification. All paint on surfaces to be inspected must be removed prior to inspection. B. Before the accumulation of 2000 hours' time in service, or before the accumulation of 2000 hours' time in service since last magnetic particle inspection, whichever is less, and at each 2000-hour interval thereafter, magnetic particle inspect the entire shaft assembly, P/N 107D3340-1 or 107D3140-1 in accordance with Boeing Vertol Overhaul Manual 107-5. C. Replace any cracked or otherwise unserviceable part found during the inspections of Paragraphs A or B with serviceable parts prior to further flight. D. An equivalent method of compliance with this AD may be used when approved by the Manager, New York Aircraft Certification Office, New England Region. This amendment becomeseffective April 4, 1983.
2005-25-17: The FAA is adopting a new airworthiness directive (AD) for certain EMBRAER airplanes listed above. This AD requires modifying the drain system of the auxiliary power unit (APU) by installing a scavenge pump and, for certain airplanes, replacing the APU exhaust assembly. This AD results from a report of fuel leaking from the APU feeding line and accumulating inside the APU compartment because the drain system is inadequate when the APU is running. We are issuing this AD to prevent fuel accumulation and subsequent flammable fuel vapors in the APU cowling, which, combined with an ignition source, could result in a fire or explosion.
82-06-51: 82-06-51 SIKORSKY: Amendment 39-4387. Applies to Sikorsky Model S-76A series helicopters certificated in all categories equipped with P/N 76351-09000-061 or prior dash-numbered main gearbox assemblies. To prevent possible failure of a main gearbox shaft and spur pinion P/N 76351-09012-103 due to fatigue cracks propagating in the bottom threaded area, accomplish the following: 1. Within the next 50 hours' time in service, unless already accomplished within the last 50 hours' time in service, and thereafter every 100 hours' time in service from the last inspection, inspect all shaft and spur pinions, P/N 76351-09012-103, with 1,500 or more hours' time in service since new on the effective date of this AD, in accordance with Sikorsky Alert Service Bulletin No. 76-66-16A or later FAA approved revision, or FAA approved equivalent. 2. Within the next 100 hours' time in service and thereafter every 100 hours' time in service from the last inspection, inspect all shaft and spur pinions, P/N 76351-09012-103, with 1,100 or more but less than 1,500 hours' time in service since new on the effective date of this AD, in accordance with Sikorsky Alert Service Bulletin No. 76-66-16A or later FAA-approved revision, or FAA approved equivalent. 3. Inspect shaft and spur pinions with less than 1,100 hours' time in service since new on the effective date of this AD before the accumulation of 1,200 hours' time in service, and thereafter every 100 hours' time in service in accordance with Sikorsky Alert Service Bulletin No. 76-66-16A or later FAA-approved revision, or FAA approved equivalent. 4. If a crack is found, replace the shaft and spur pinion with a serviceable part prior to further flight. 5. Replace the shaft and spur pinions, P/N 76351-09012-103, with a serviceable part prior to the accumulation of 1,500 hours' time in service since new or within 200 hours' time in service after the effective date of this AD, whichever occurs later. Thereafter, replace shaft and spur pinions with serviceable parts prior to accumulation of 1,500 hours' time in service. 6. All shaft and spur pinions whose hours' time in service cannot be established are to be inspected in accordance with paragraph 1 and are to be replaced with a serviceable part within 200 hours' time in service from the effective date of this AD. Equivalent means of compliance may be approved by the Chief, Boston Aircraft Certification Branch, Federal Aviation Administration, New England Region, 12 New England Executive Park, Burlington, Massachusetts 01803. This amendment becomes effective June 3, 1982, to all persons except those persons to whom it was made immediately effective by telegraphic AD T82-06-51, issued March 5, 1982, which contained this amendment.