Results
2013-09-11: We are adopting a new airworthiness directive (AD) for certain Cessna Aircraft Company Model 500, 501, 550, 551, S550, 560, 560XL, and 650 airplanes. This AD was prompted by multiple reports of smoke and/or fire in the tailcone caused by sparking due to excessive wear of the brushes in the air conditioning (A/C) motor. This AD requires inspecting to determine if certain A/C compressor motors are installed and to determine the accumulated hours on certain A/C drive motor assemblies; repetitive replacement of the brushes in the drive motor assembly, or, as an option to the brush replacement, deactivation of the A/C system and placard installation; and return of replaced brushes to Cessna. We are issuing this AD to prevent the brushes in the A/C motor from wearing down beyond their limits, which could result in the rivet in the brush contacting the commutator causing sparks and consequent fire and/or smoke in the tailcone with no means to detect or extinguish the fire and/or smoke.
2022-15-03: The FAA is superseding Airworthiness Directive (AD) 2021-14-06 for all Pratt & Whitney (PW) PW1519G, PW1521G, PW1521G-3, PW1521GA, PW1524G, PW1524G-3, PW1525G, PW1525G-3, PW1919G, PW1921G, PW1922G, PW1923G, and PW1923G-A model turbofan engines. AD 2021-14-06 required repetitive borescope inspections (BSI) of certain low-pressure compressor (LPC) rotor 1 (R1) until replacement of electronic engine control (EEC) full authority digital electronic control (FADEC) software with updated software. AD 2021-14-06 also required a BSI after installation of the updated EEC FADEC software if certain Onboard Maintenance Message fault codes are displayed and meet specified criteria. AD 2021-14-06 also required, depending on the results of the BSI, replacement of the LPC R1. Since the FAA issued AD 2021-14-06, the manufacturer redesigned the compressor intermediate case (CIC) assembly to incorporate a shortened bleed duct configuration and updated the EEC FADEC software. This AD continues to require repetitive BSI of certain LPC R1s until replacement of EEC FADEC software with updated software and also a BSI after installation of the updated EEC FADEC software if certain Onboard Maintenance Message fault codes are displayed and meet specified criteria. This AD continues to require, depending on the results of the BSI, replacement of the LPC R1. This AD also requires removal and replacement of the existing CIC assembly with a CIC assembly eligible for installation. The FAA is issuing this AD to address the unsafe condition on these products.
2004-18-13: This amendment supersedes an existing airworthiness directive (AD), applicable to certain Airbus Model A300 B2 and B4 series airplanes, and Model A300 B4-601, B4-603, B4-605R, B4-620, B4-622R, C4- 605R Variant F, and F4-605R airplanes, that currently requires a one- time inspection for cracking of the gantry lower flanges in the main landing gear (MLG) bay area; and repair, if necessary. This amendment removes an airplane model from the applicability. This amendment, for certain airplanes, retains the one-time inspection for cracking of the gantry lower flanges and repair, if necessary. For other airplanes, this amendment adds repetitive inspections of the gantry lower flanges; repair, if necessary; and reinforcement of the left-hand and right-hand gantry. The actions specified by this AD are intended to detect and correct cracking of the gantry lower flanges in the MLG bay area, which could result in decompression of the airplane. This action is intended to address the identified unsafe condition. DATES: Effective October 19, 2004. The incorporation by reference of Airbus Service Bulletin A300-53- 6128, dated March 5, 2001, as listed in the regulations, is approved by the Director of the Federal Register as of October 19, 2004. The incorporation by reference of Airbus All Operators Telex (AOT) 53-11, dated October 13, 1997, as listed in the regulations, was approved previously by the Director of the Federal Register as of July 30, 1998 (63 FR 34589, June 25, 1998).
2013-10-05: We are adopting a new airworthiness directive (AD) for Eurocopter Deutschland GmbH (ECD) Model MBB-BK 117 C-2 helicopters. This AD requires revising the operating limitations to prohibit flights under instrument flight rules (IFR) or under night visual flight rules (VFR) when the autotrim is inoperative. The actions of this AD are intended to prevent a workload situation whereby stabilizing the helicopter in flight would be difficult if not impossible, resulting in possible loss of helicopter control.
2013-10-01: We are adopting a new airworthiness directive (AD) for a certain Spectrolab Nightsun XP Searchlight Assembly (searchlight) installed on, but not limited to Agusta S.p.A. (Agusta) Model AB139 and Model AW139 helicopters, Sikorsky Aircraft Corporation (Sikorsky) Model S-92A helicopters, and Eurocopter Deutschland GmbH (Eurocopter) Model EC135 and Model MBB-BK 117 C-2 helicopters. This AD requires, before further flight, inserting information into the Normal Procedures section of the Rotorcraft Flight Manual (RFM), a daily check of the searchlight, and at a specified time interval or if certain conditions are found, modifying any affected searchlight gimbal assembly. This AD was prompted by a report of a searchlight vibrating and an investigation that revealed that the gimbal azimuth top nut was loose. A loose nut, if not detected and corrected, could result in a gap between the rubber edging of the top shroud and the gimbal frame, leading to degradation of pointing accuracy andstability performance of the searchlight and excessive vibration. If the nut were to entirely disengage, the searchlight could disconnect partially or totally from the helicopter, resulting in damage to the helicopter and injury to persons on the ground. The actions of this AD are intended to ensure that the searchlight remains firmly attached to the helicopter.
70-10-03: 70-10-03 GENERAL DYNAMICS: Amdt. 39-985. Applies to General Dynamics Model 240 airplanes equipped with Rolls Royce MK 542-4/-4K engines and Dowty Rotol (C)R245/4- 40-4.5/13 propellers in accordance with General Dynamics Supplemental Type Certificate SA1054WE (hereinafter referred to as the CV-600) and General Dynamics Model 340 and 440 airplanes equipped with Rolls Royce MK 542-4/-4K engines and Dowty Rotol (c)R245/4-40- 4.5/13 or Dowty Rotol (c)R259/4-40-4.5/17 propellers in accordance with General Dynamics Supplemental Type Certificate SA1096WE (hereinafter referred to as the CV-640). Compliance required as indicated. To preclude the possibility of engine breather oil and fumes seeping around the engine oil breather overboard discharge tube and between the trough and deflector assembly and being drawn into the nacelle afterbody, accomplish the following: (a) Within 250 hours time in service after the effective date of this A.D. unless already accomplished install anextension of the engine oil breather overboard discharge tube in accordance with 2A. Part I of General Dynamics/Convair Service Bulletin 600(240D) S.B. No. 71-2B/640 (340D), S.B. No. 71-2B, dated 17 April 1970, Reissue B, or later FAA approved revisions, or an equivalent modification approved by the Chief, Aircraft Engineering Division, FAA Western Region. (b) Within 450 hours time in service unless already accomplished weld the breather tube to the collar of the trailing edge assembly of the trough installation to effect a positive seal in accordance with 2B Part II or 2C Part III of General Dynamics/Convair Service Bulletin 600(240D), S.B. No. 71-2B/640(340D) S.B. No. 71-2B dated 17 April 1970, Reissue B or later FAA approved revisions, or an equivalent modification approved by the Chief, Aircraft Engineering Division, FAA Western Region. (c) Concurrent with (a), above, and until (b) above is accomplished seal the area surrounding the oil breather tube at the nacelle afterbody trailing edge with HT-1 Stabond sealant or similar sealing material. Inspect this sealant every 50 hours time in service and replace sealant material as necessary. This supersedes Amendment 39-957, AD 70-06-06 (published in 35 F.R.4547). This amendment becomes effective May 12, 1970.
96-20-10: This amendment adopts a new airworthiness directive (AD) that is applicable to certain Lockheed Model L-1011-385 series airplanes. This action requires inspections to detect cracking of the canted pressure bulkhead at fuselage station (FS) 1212, and inspections to detect cracking of the web at the fastener rows of the vertical stiffener-to-web; and repair or replacement of the web with a new web, if necessary. This amendment is prompted by a report of fatigue cracking of the canted pressure bulkhead at FS 1212. The actions specified in this AD are intended to detect and correct such fatigue cracking, which could result in blowout of a panel between adjacent stiffeners and consequent cabin depressurization.
2013-10-02: We are superseding an existing airworthiness directive (AD) for certain The Boeing Company Model 757-200 and -200PF series airplanes. That AD currently requires modifying the nacelle strut and wing structure, and repairing any damage found during the modification. This new AD specifies a maximum compliance time limit that overrides the optional threshold formula results. This AD was prompted by reports indicating that the actual operational loads applied to the nacelle are higher than the analytical loads that \n\n((Page 28730)) \n\nwere used during the initial design. Subsequent analysis and service history, which includes numerous reports of fatigue cracking on certain strut and wing structure, indicated that fatigue cracking can occur on the primary strut structure before an airplane reaches its design service objective. We are issuing this AD to prevent fatigue cracking in primary strut structure and consequent reduced structural integrity of the strut.
2004-18-15: This amendment supersedes an existing airworthiness directive (AD), applicable to McDonnell Douglas transport category airplanes listed above, that currently requires a one-time detailed inspection to determine if wire segments of the wire bundle routed through the feed- through on the aft side of the flight engineer's station are damaged or chafed, and corrective actions if necessary. That AD also requires revising the wire bundle support clamp installation at the flight engineer's station. For certain airplanes, this amendment requires a new revision of the wire bundle support clamp installation, and modification of a certain wire bundle. This amendment also reduces the applicability in the existing AD. The actions specified by this AD are intended to prevent chafing of the wire bundle located behind the flight engineer's panel caused by the wire bundle coming in contact with the lower edge of the feed-through, and consequent electrical arcing, which could result in smoke and fire in the cockpit. This action is intended to address the identified unsafe condition. \n\nDATES: Effective October 19, 2004. \n\n\tThe incorporation by reference of certain publications, as listed in the regulations, is approved by the Director of the Federal Register as of October 19, 2004. \n\n\tThe incorporation by reference of Boeing Alert Service Bulletin DC10-24A149, Revision 02, dated April 5, 2001, as listed in the regulations, was approved previously by the Director of the Federal Register as of January 16, 2002 (66 FR 64121, December 12, 2001). \n\n\tThe incorporation by reference of McDonnell Douglas Alert Service Bulletin DC10-24A149, Revision 01, dated July 28, 1999, as listed in the regulations, was approved previously by the Director of the Federal Register as of June 21, 2000 (65 FR 31253, May 17, 2000).
2013-09-06: We are superseding an existing airworthiness directive (AD) for [[Page 28728]] Agusta S.p.A. (Agusta) Model A119 and AW119 MKII helicopters. The existing AD currently requires inspecting the pilot and copilot engine rotary variable differential transformer (RVDT) control box assemblies to determine if the control gear locking pin is in its proper position. Since we issued that AD, Agusta has developed a terminating action for this inspection. This AD requires the same actions as the existing AD as well as modifying the RVDT control box assemblies. The actions of this AD are intended to prevent failure of an RVDT control box assembly, loss of manual control of the engine throttle, and subsequent loss of control of the helicopter.
68-25-04: 68-25-04 VICKERS: Amendment 39-691. Applies to Viscount Models 744, 745D and 810 Series Airplane. Compliance required as indicated unless already accomplished. To prevent fatigue failure of the nose wheel steering twin relief valve, P/N 70026 Sh. 35 at the valve body halves P/N 70026, Part 251 and Part 253, accomplish the following: (a) Inspect the valve body halves as specified in paragraph (b) at the following times: (1) Valves having less than 14,650 hours time in service on the effective date of the AD must be inspected prior to the accumulation of 15,000 hours time in service and thereafter at intervals not to exceed 2500 hours time in service. (2) Valves that have accumulated 14,650 or more but less than 20,000 hours time in service on the effective date of this AD must be inspected within the next 350 hours time in service and thereafter at intervals not to exceed 2500 hours time in service. (3) Valves that have accumulated 20,000 or more but lessthat 22,800 hours time in service on the effective date of this AD must be inspected within the next 350 hours time in service and thereafter at intervals not to exceed 1000 hours time in service. (4) Valves that have accumulated 22,800 or more hours time in service on the effective date of this AD must be inspected within the next 350 hours time in service. (b) Inspect the valve body halves for cracks at the fluid transfer holes by a dye penetrant method in accordance with British Aircraft Corporation Viscount Preliminary Technical Leaflet No. 265 Issue 2 (700 Series) or No. 128 Issue 2 (810 Series) or later ARB approved issue or an FAA approved equivalent. (c) Replace the valve body halves in accordance with paragraph (d) at the following times: (1) If cracks are found during the inspections required by paragraph (a), replace the valve body halves prior to further flight. (2) If no cracks are found during the inspections required by paragraph (a), replace the valve body halves as follows: (i) Valves having less than 14,650 hours time in service on the effective date of this AD, must be replaced before the accumulation of 20,000 hours time in service. (ii) Valves having 14,650 or more but less than 22,800 hours time in service on the effective date of this AD must be replaced before the accumulation of 23,500. (iii) Valves having 22,800 or more hours time in service on the effective date of this AD must be replaced within the next 750 hours time in service after the effective date of this AD. (d) Replace valve body halves with parts having the same part numbers which have been inspected and found to have no cracks or with new valve body halves P/N 70026-637-639. (e) Valves of the same part numbers used as replacements must continue to be inspected in accordance with paragraph (a) and replaced in accordance with paragraph (c). Compliance with the inspection and replacement requirements of this AD may be discontinued when new valves P/N 70026-637-639 are incorporated. This amendment becomes effective January 7, 1969.
2004-18-07: This amendment supersedes an existing airworthiness directive (AD), applicable to certain BAE Systems (Operations) Limited Model BAe 146 and Avro 146-RJ series airplanes, that currently requires identifying the part numbers of discharge valves and cabin pressure controllers, and related investigative and corrective actions if necessary. This amendment requires identifying the part number of an additional cabin pressure controller, and related investigative and corrective actions if necessary. The actions specified by this AD are intended to prevent the installation of incorrect pressurization discharge valves and cabin pressure controllers, which could subject the airframe to excess stress and adversely affect the airframe fatigue life. This action is intended to address the identified unsafe condition. DATES: Effective October 13, 2004. The incorporation by reference of a certain publication listed in the regulations is approved by the Director of the Federal Register as of October 13, 2004. The incorporation by reference of a certain other publication listed in the regulations was approved previously by the Director of the Federal Register as of September 10, 2001 (66 FR 40864, August 6, 2001).
2012-18-13 R1: We are revising an existing airworthiness directive (AD) for all The Boeing Company Model 737-100, -200, -200C, -300, -400, and -500 series \n\n((Page 27021)) \n\nairplanes. That AD currently requires repetitive inspections to detect cracking in the web of the aft pressure bulkhead at body station 1016 at the aft fastener row attachment to the ''Y'' chord, various inspections for discrepancies at the aft pressure bulkhead, and related investigative and corrective actions if necessary. This new AD requires clarifying certain actions specified in the existing AD. This AD was prompted by several reports of fatigue cracks in the aft pressure bulkhead. We are issuing this AD to detect and correct such fatigue cracking, which could result in rapid decompression of the fuselage.
2022-13-14: The FAA is adopting a new airworthiness directive (AD) for all Airbus Helicopters Model AS-365N2, AS 365 N3, EC 155B, EC155B1, and SA- 365N1 helicopters. This AD was prompted by a large amount of critical scale particles found on the tail rotor gearbox (TGB) chip detector magnetic plug during an unscheduled check of the TGB. The particles belonged to the double bearing (pitch control rod bearing) installed inside the TGB. This AD requires repetitive inspections of the TGB chip detector for particles, analyzing any particles collected, performing a double bearing washing, repetitive replacements of certain part- numbered double bearings, and corrective actions if necessary, as specified in a European Union Aviation Safety Agency (EASA) AD, which is incorporated by reference. The FAA is issuing this AD to address the unsafe condition on these products.
47-47-12: 47-47-12 REPUBLIC: (Was Mandatory Note 12 of AD-769-2.) Applies to RC-3 Aircraft Serial Numbers 5 Through 1035 Inclusive Except the Following Which Have Been Modified at the Factory: 767, 915, 948, 949, 957, 959 Through 999 Inclusive, 1004 Through 1010 Inclusive, 1014, 1019 Through 1025 Inclusive. Serial 1036 and up Have Been Modified at the Factory Prior to Delivery. Compliance required not later than December 31, 1947. To prevent excessive drop-off in engine r.p.m. when carburetor heat is used, anti-swirl vanes, Republic P/N 17P 68014-20 must be installed in the air duct below the carburetor. (Republic Seabee Service Bulletin No. 18 dated August 26, 1947, covers this same subject.)
59-14-02: 59-14-02 MOONEY: Applies to M-20 Airplanes Serial Numbers 1175 Through 1200 and M-20A Airplanes Serial Numbers 1201 Through 1375. Compliance required prior to August 1, 1959. To guard against fuel selector valve failure and inability to change selector valve position the following inspection and replacement is required prior to August 1, 1959. Replacement valves obtained from the factory after April 27, 1959, and installed need not comply with this AD. (a) Remove fuel tank selector valve. (b) Remove lower part of valve housing and remove plastic core. (c) Determine if the shaft and plastic core are pinned together. If not, replace complete valve assembly with replacement valve P/N 311-221-1/4D obtained from Mooney. (Mooney Service Letter 20-48 concerns this subject.)
92-11-06: 92-11-06 BRITISH AEROSPACE: Amendment 39-8256. Docket No. 92-NM-06-AD. Applicability: British Aerospace Model BAe 146-100A, 200A, and 300A series airplanes, certificated in any category. Compliance: Required as indicated, unless accomplished previously. To prevent the generation of incorrect air speed and altitude information, accomplish the following: (a) For British Aerospace Model BAe 146-200A series airplanes with Serial Numbers E2164 and subsequent; and Model BAe 146-300A series airplanes with Serial Numbers E3118, E3163, and subsequent: Within 30 days after the effective date of this AD, accomplish the actions specified in paragraphs (a)(1), (a)(2), and (a)(3) of this AD, in accordance with instructions in British Aerospace Service Bulletin SB.34-128-00950J, dated March 22, 1991: (1) Replace existing pitot-static system hoses at specified location with shorter hoses. (2) Check the clamp block bolts installation. If any discrepancy is detected, correct it prior to further flight. (3) Conduct a leak test of the pitot-static system. If any discrepancy is detected, correct it prior to further flight. (b) For British Aerospace Model BAe 146-100A, 200A, and 300A series airplanes equipped with a True Airspeed Computer No. 1 in accordance with modification HCM40159B or HCM40297G, along with a Mode "S" Transponder in accordance with modification HCM30118B or HCM40277A: Within 90 days after the effective date of this AD, accomplish the actions specified in paragraphs (b)(1) and (b)(2) of this AD, in accordance with instructions in British Aerospace Service Bulletin SB.34-131-46041A, dated June 24, 1991: (1) Replace existing pitot-static system hoses at specified locations with shorter hoses. (2) Conduct a leak test of the pitot-static system. If any discrepancy is detected, correct it prior to further flight. (c) For British Aerospace Model BAe 146-100A, 200A, and 300A series airplanes equipped with a True Airspeed Computer No. 2 in accordance with modification HCM40160C or HCM40298G, along with a Mode "S" Transponder in accordance with modification HCM30118B or HCM40277A: Within 90 days after the effective date of this AD, accomplish the actions specified in paragraphs (c)(1) and (c)(2) of this AD, in accordance with instructions in British Aerospace Service Bulletin SB.34-132-46042A, dated June 24, 1991: (1) Replace existing pitot-static system hoses at specified locations with shorter hoses. (2) Conduct a leak test of the pitot-static system. If any discrepancy is detected, correct it prior to further flight. (d) An alternative method 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, Transport Airplane Directorate. The request shall be forwarded through an FAA Principal Maintenance Inspector, who may concur or comment and then send it to the Manager, Standardization Branch, ANM-113. (e) 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. (f) The inspections and modifications shall be done in accordance with British Aerospace Service Bulletin SB.34-128-00950J, dated March 22, 1991; British Aerospace Service Bulletin SB.34-131-46041A, dated June 24, 1991; or British Aerospace Service Bulletin SB.34-132-46042A, dated June 24, 1991; as applicable. 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 British Aerospace, PLC. Librarian for Service Bulletins, P.O. Box 17414, Dulles International Airport, Washington D.C. 20041-0414. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., Renton, Washington; or at the Office of the Federal Register, 1100 L Street NW., Room 8401, Washington, DC. (g) This amendment becomes effective on July 9, 1992.
2004-18-11: This amendment adopts a new airworthiness directive (AD), applicable to certain McDonnell Douglas Model DC-9-14, DC-9-15, and DC- 9-15F airplanes; and Model DC-9-20, DC-9-30, DC-9-40, and DC-9-50 series airplanes. This amendment requires, among other actions, performing repetitive inspections for cracking of the counterbore of the two lower mounting holes and the lower forward edge of the outboard idler hinge fitting of the left and right wing flap at station Xw=333.148, and replacing the flap idler hinge fitting with a new or serviceable part. This action is necessary to prevent failure of the outboard idler hinge fitting of the left and right wing flap at station Xw=333.148 due to fatigue cracking, which could result in a deflected flap that may cause asymmetric lift and consequent reduced controllability and structural integrity of the airplane. This action is intended to address the identified unsafe condition.
2022-13-04: The FAA is superseding Airworthiness Directive (AD) 2017-24- 10, which applied to certain The Boeing Company Model 757-200, -200PF, and -300 series airplanes. AD 2017-24-10 required repetitive inspections for any cracking of a certain fuselage frame inner chord; identification of the material of a certain fuselage frame inner chord for certain airplanes; and applicable corrective actions. This AD was prompted by reports of cracking found at a certain fuselage frame inner chord. This AD retains the requirements of AD 2017-24-10, adds airplanes, and requires new inspection types in certain areas, an expanded inspection area, additional inspections, and applicable corrective actions. The FAA is issuing this AD to address the unsafe condition on these products.
2013-08-16: We are adopting a new airworthiness directive (AD) for certain The Boeing Company Model 737-700 and -700C series airplanes. This AD was prompted by reports of early fatigue cracks at chem-mill areas on the crown skin panels. This AD requires repetitive inspections for cracking of the fuselage skin at certain locations at chem-mill areas, and repair if necessary. We are issuing this AD to detect and correct fatigue cracking of the skin panel at the specified chem-mill step locations, which could result in rapid decompression of the airplane.
2013-03-18: We are adopting a new airworthiness directive (AD) for Eurocopter Deutschland GmbH (Eurocopter) Model MBB-BK 117 C-2 helicopters. This AD requires inspecting the long tail rotor drive shaft assembly for blind rivets, and if any blind rivets are installed, replacing that shaft assembly. This AD was prompted by the discovery that some helicopters have blind rivets installed in the place of solid rivets in the long tail rotor drive shaft. The actions of this AD are intended to detect blind rivets installed in the long tail rotor drive shaft, which could lead to failure of the tail rotor drive shaft and subsequent loss of control of the helicopter.
99-19-22: This document publishes in the Federal Register an amendment adopting Airworthiness Directive (AD) 99-19-22 which was sent previously to all known U.S. owners and operators of Eurocopter Deutschland GMBH (ECD) Model BO-105A, BO-105C, BO-105 C-2, BO-105 CB-2, BO-105 CB-4, BO-105S, BO-105 CS-2, BO-105 CBS-2, BO-105 CBS-4, and BO-105LS A-1 helicopters by individual letters. This AD requires, before further flight, creating a component log card or equivalent record and determining the age and number of flights on each tension-torsion (TT) strap. The AD also requires inspecting and removing, as necessary, certain unairworthy TT straps. This amendment is prompted by an accident in which a main rotor blade (blade) separated from an ECD Model MBB-BK 117 helicopter because of fatigue failure of the TT strap. The ECD Model MBB-BK 117 and the BO-105 helicopters use the same part-numbered TT strap. The actions specified by this AD are intended to prevent failure of a TT strap, lossof a blade, and subsequent loss of control of the helicopter.
2013-08-15: We are adopting a new airworthiness directive (AD) for certain The Boeing Company Model 737-800 series airplanes. This AD was prompted by reports of early fatigue cracks at chem-mill areas on the crown skin panels. This AD requires repetitive inspections for cracking of the fuselage skin along chem-mill steps at certain crown skin and shear wrinkle areas, and repair if necessary. We are issuing this AD to detect and correct fatigue cracking of the skin panel at the specified chem-mill step locations, which could result in rapid decompression of the airplane.
96-18-17: This amendment adopts a new airworthiness directive (AD), applicable to AlliedSignal Inc. (formerly Garrett) TSCP700-4B, -4E, and -5 auxiliary power units (APUs), that requires removal from service of certain high pressure turbine (HPT) disks identified by serial number, and replacement with serviceable parts. This amendment is prompted by the discovery of a material defect in certain HPT disk forgings that may result in HPT disk rupture prior to reaching the disk cyclic life limit. The actions specified by this AD are intended to prevent an HPT disk rupture.
70-06-02: 70-06-02 BELL: Amdt. 39-955. Applies to all Model 204B 205A and 205A-1 helicopters and to any other helicopter incorporating tail rotor hub assembly, P/N 204-011-801-5 or -7 or P/N 204-011-701-11, -13 or -19 and to all spare tail rotor hub assemblies P/N 205-011-801-5 or -7 or P/N 204-011-701-11, -13 or -19. Compliance required as indicated. To prevent failure of the grip assemblies, P/N 204-011-728 or P/N 204-011-706, accomplish the following one time inspection on all tail rotor grip assemblies for proper hardness or conductivity before further flight, unless already accomplished after February 27, 1970. These inspections may be conducted with the grips installed on the helicopter. Determine the hardness of the grip assembly using a Rockwell Hardness or Eddy Current Tester, a Magnatest FM-120 (Magnaflux Corp.) or equivalent. Readings should be taken adjacent to vibro etched serial number between the blade retention bolts on grip face. Inspect all spare grip assemblies before installation. Remove grip assemblies with readings below Rockwell 79 on the "B" scale or above conductivity of 39 on International Annealed Copper Standard. This supersedes Amendment 39-953 (AD 70-06-01) issued by telegram dated February 27, 1970. This amendment is effective March 13, 1970, and was effective for all recipients of the telegram dated March 4, 1970 which contained this amendment.