Results
2012-01-04: We are adopting a new airworthiness directive (AD) for certain Model CN-235-100, CN-235-200, and CN-235-300 airplanes. This AD was prompted by reports of failures of the engine condition control cable which led to an engine shut down. This AD requires an inspection to determine the part number of the engine condition control cable, repetitive inspections for excessive wear of the affected engine condition control cable, and replacement of the affected part. We are issuing this AD to detect and correct failure of the engine condition control cable which could cause a consequent runway excursion during take-off, or reduced control of the airplane during flight.
98-12-02: This amendment adopts a new airworthiness directive (AD) that applies to certain SOCATA Groupe Aerospatiale (SOCATA) Model TBM 700 airplanes. This AD requires inspecting the elevator trim tab fittings for cracks, and replacing any elevator trim tab found to have cracks. This 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 prevent cracks in the elevator trim tab fittings, which could result in separation of the elevator trim tab and loss of control of the airplane.
2012-02-08: We are adopting a new airworthiness directive (AD) for certain ACSS TCAS units installed on but not limited to various transport and small airplanes. This AD was prompted by reports of anomalies with TCAS units during a flight test over a high density airport. The TCAS units dropped several reduced surveillance aircraft tracks because of interference limiting. This AD requires upgrading software. We are issuing this AD to prevent TCAS units from dropping tracks, which could compromise separation of air traffic and lead to subsequent mid-air collisions.
98-12-06: This amendment adopts a new airworthiness directive (AD) that applies to certain Stemme GmbH & Co. KG (Stemme) Models S10 and S10-V sailplanes. This AD requires replacing the fuel filter if it is contaminated, inserting a revision to the Limitations Section of the flight manual, and inspecting the engine valve shafts for brownish-black sticky residue. If a residue is found on the valve shafts, this action will require cleaning the engine. This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Germany. The actions specified by this AD are intended to prevent engine valve malfunction, which could cause engine failure during flight and loss of control of the sailplane.
71-13-01R1: We are rescinding an airworthiness directive (AD) for Lycoming Engines model TIO-540-A series reciprocating engines. The existing AD, AD 71-13-01, was prompted by a report of a failed fuel injector tube assembly. Since we issued AD 71-13-01, we became aware that Lycoming Engines no longer supports Service Bulletin (SB) No. 335A, which was incorporated by reference in AD 71-13-01. The intent of the requirements of that SB is now in Lycoming Engines Mandatory SB No. 342F, which we have incorporated by reference into AD 2008-14-07. The FAA determined, therefore, that this requirement is duplicated by another AD.
69-20-05: 69-20-05\tBOEING: Admt. 39-851. Applies to Models 707 and 720 Series Aircraft listed in Subpart 1, A, "Effectivity," of Weber Service Bulletin No. 30R, dated September 5, 1969, or later FAA approved revision. \n\tCompliance required as indicated, unless already accomplished. \n\tTo prevent occurrence of a hazardous fire condition in and around the lavatory electrical razor outlet terminals, accomplish the following: \n\t(a)\tWithin the next 25 hours' time in service after the effective date of this AD, deactivate the razor terminal outlets by pulling all applicable AC and DC circuit breakers. Secure circuit breakers in the open position with suitable collars and affix a placard worded, "Inoperative," adjacent to the breakers. Outlets may be reactivated upon accomplishment of paragraph (b) below. \n\t(b)\tInstall the shelf, fiberglass cover box, and fiberglass retainer in accordance with the instructions of Part 2, "Accomplishment Instructions," of Weber Service Bulletin No. 30R, Revisiondated September 5, 1969, or later FAA approved revision, or an equivalent installation approved by the Chief, Aircraft Engineering Division, FAA Western Region. \n\tThis amendment becomes effective October 2, 1969.
2012-02-12: We are adopting a new airworthiness directive (AD) for certain Bombardier, Inc. Model DHC-8-400, -401, and -402 airplanes. This AD requires an inspection of a certain alternating current (AC) power wire bundle for damage, and repair if necessary. Additionally, this AD requires segregating the wire bundle into two wire bundles and installing Teflon tubing. This AD was prompted by multiple reports of the loss of certain AC systems caused by a burnt AC power wire bundle. We are issuing this AD to prevent the loss of ice protection systems for the angle of attack vanes, pitot probes, engine inlets, and windshields, and consequent loss of or misleading airspeed indication and increased workload for the flight crew, which could lead to loss of control of the airplane.
2003-06-01: This amendment supersedes Airworthiness Directive (AD) 2002- 13-02, which applies to all Air Tractor, Inc. (Air Tractor) Models AT- 300, AT-301, AT-302, and AT-400A airplanes that have aluminum spar caps; certain Air Tractor Models AT-400 airplanes that have aluminum spar caps; and all Models AT-300 and AT-301 airplanes that have aluminum spar caps and are or have been converted to turbine power. AD 2002-13-02 currently requires you to inspect (one-time) the wing centerline splice joint for cracks and, if any crack is found, replace the affected wing spar lower cap; requires you to report the results of the inspection to the Federal Aviation Administration (FAA); and requires you to replace the wing spar lower caps after a certain amount of usage. Based upon the inspection results from AD 2002-13-02, FAA has determined that the mandatory wing spar lower cap replacement times should be reduced. This AD maintains the wing spar lower cap replacement and reporting requirements from AD 2002-13-02 and reduces the compliance time of these replacements. The actions specified by this AD are intended to detect and correct cracks in the wing centerline splice joint. If not detected and corrected, these cracks could eventually result in the wing separating from the airplane during flight.
69-11-01: 69-11-01 SWEARINGEN : Amdt. 39-767. Applies to Model SA26-T, S/N T26-2 through S/N T26-99, and Model SA26-AT, S/N T26-100 through S/N T26-142. Compliance required as indicated. To prevent failures of cockpit side windows, P/N 26-21288-1 and P/N 26-21288-2, accomplish the following: (1) After the effective date of this AD: (a) Operate aircraft with cabin pressure differential not in excess of 5.0 psi. (b) Prior to the first flight, install placard in full view of pilot calling out maximum allowable cabin pressure differential of 5.0 psi. (c) Prior to each flight, inspect cockpit side windows for cracks, with particular attention to all edges and corners. (2) If any crack is found, airplanes may be operated unpressurized only. (3) Upon installation of new cockpit side windows, P/N 26-21383-5 and -6, in accordancewith Swearingen Aircraft Service Bulletin No. 26-68 dated April 28, 1969, or later FAA-approved revision or an equivalent method approved by the Chief, Engineering and Manufacturing Branch, Flight Standards Division, Southwest Region, FAA, the 5.0 psi limiting placard may be removed and the requirements of this AD discontinued. This amendment becomes effective May 26, 1969.
2012-02-05: We are adopting a new airworthiness directive (AD) for all Thielert Aircraft Engines GmbH (TAE) [[Page 4218]] TAE 125-02-99 and TAE 125-02-114 reciprocating engines. This AD was prompted by in-flight engine shutdown incidents reported on airplanes equipped with TAE 125 engines. We are issuing this AD to prevent in- flight engine shutdown, which could result in loss of control of the airplane.
2012-01-11: We are adopting a new airworthiness directive (AD) for certain Cirrus Design Corporation (Cirrus) Model SR22T airplanes. This AD was prompted by reports of partial loss of engine power due to a dislodged rubber gasket/seal being ingested into the turbocharger. This AD requires inspection and modification of the air box flange welds and slots and installation of induction system air box seals as applicable. We are issuing this AD to correct the unsafe condition on these products.
81-26-01 R1: 81-26-01 R1 MCDONNELL DOUGLAS HELICOPTER COMPANY (MDHC): Amendment 39-4275 as revised by Amendment 39-6689. Docket No. 89-ASW-43. Applicability: All Model 369 series helicopters equipped with main rotor drive shaft, part number (P/N) 369D25510, certificated in any category. Compliance: Required as indicated, unless already accomplished. To prevent failure of the main rotor drive shaft, P/N 369D25510, which could result in the loss of the helicopter, accomplish the following: (a) Prior to the accumulation of 300 hours' total time in service on the P/N 369D25510 drive shaft, or within the next 25 hours' additional time in service from December 17, 1981, for the Model 369D or from the effective date of this amended AD for Models 369E and F (whichever occurs later), and thereafter at repetitive intervals not to exceed 300 hours' additional time in service since the last such inspection: (1) Visually inspect the spherical spline and adjacent shaft area of thedrive shaft, P/N 369D25510, in accordance with the instructions contained in Hughes Service Information Notices (SIN) DN-99, dated November 30, 1981; FN-4, dated July 29, 1983; or MDHC SIN EN- 4, dated April 29, 1983, as applicable. (2) Replace cracked parts with like serviceable part prior to return to service and continue to inspect at 300-hour intervals. NOTE: Drive shaft retirement is established at 3,410 hours' time in service. (3) Drive shaft retirement is established at 3,410 hours' time in service for Models 369F and FF, and 5,020 hours' time in service for Models 369D and E. (b) Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate aircraft to a base for the accomplishment of inspections or modifications required by this AD. (c) An alternative method of compliance, which provides an equivalent level of safety, may be used when approved by the Manager, Los Angeles Aircraft Certification Office, ANM-100L, FAA, Northwest Mountain Region, 3229 East Spring Street, Long Beach, California 90806-2425; telephone (213) 988-5200. The repair and inspection procedures shall be done in accordance with Hughes Service Information Notices (SIN) DN-99, dated November 30, 1981, incorporated by reference (See 46 FR 60807, December 14, 1981); FN-4, dated July 29, 1983; or MDHC SIN EN-4, dated April 29, 1983, 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 McDonnell Douglas Helicopter Company, 5000 E. McDowell Road, Attention: Publications Department, MS 543/P 213, Mesa, Arizona 85205. Copies may be inspected at the Regional Rules Docket, Office of the Assistant Chief Counsel, Federal Aviation Administration, 4400 Blue Mound Road, Room 158, Bldg. 3B, Fort Worth, Texas, or at the Office of the Federal Register, 1100 L Street, NW., Room 8301, Washington, DC. Airworthiness Directive 81-26-01 R1 revises AD 81-26-01, Amendment 39-4275 (46 FR 60807, December 14, 1981). This amendment (39-6689), AD 81-26-01 R1) becomes effective on October 31, 1990.
2025-08-05: The FAA is adopting a new airworthiness directive (AD) for certain Airbus SAS Model A319-111, -112, -113, -114, -115, -131, -132, and -133 airplanes. This AD was prompted by a widespread fatigue damage (WFD) scenario review for a certification project that indicated several cracks found around the potable water and wastewater service panels were WFD instead of typical fatigue. This AD requires modification of the potable water and wastewater service panels, 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.
2018-03-22: We are adopting a new airworthiness directive (AD) for GE Aviation Czech s.r.o. M601D-11, M601E-11, M601E-11A, M601E-11AS, M601E- 11S, and M601F turboprop engines. This AD requires removal of certain power turbine (PT) disks installed on the affected engines. This AD was prompted by a design review by the manufacturer that determined PT rotors with certain disks have less overspeed margin than originally stated during product certification. We are issuing this AD to address the unsafe condition on these products.
2003-05-10: This amendment supersedes an existing airworthiness directive (AD), that is applicable to General Electric Company (GE) CF34-3A1, -3B, and -3B1 turbofan engines with scavenge screens part numbers (P/Ns) 4047T95P01 and 5054T86G02 installed in the B-sump oil scavenge system. That AD currently requires initial and repetitive visual inspections and cleaning of the B-sump scavenge screens. This amendment requires initial and repetitive visual inspections and cleaning of the B-sump scavenge screens until a screenless fitting is installed. This amendment is prompted by six reports of B-sump oil scavenge system failure causing engine in-flight shutdowns. The actions specified by this AD are intended to prevent B-sump scavenge screen blockage due to coking, which could result in ignition of B-sump oil in the secondary air system, fan drive shaft separation, and uncontained engine failure.
2003-05-05: This amendment adopts a new airworthiness directive (AD) that applies to certain Robert E. Rust (R.E. Rust) Models DeHavilland DH.C1 Chipmunk 21, 22, and 22A airplanes. This AD requires you to inspect the fuselage to determine if a steel fuselage center-section tie bar fitted with bushings in the end lug bolt holes is installed. If this bushed steel fuselage center-section tie bar is installed, this AD decreases the safe life limit. This AD is the result of reports that certain replacement steel fuselage center-section tie bars installed on the affected airplanes could fail before the originally published safe life limit. The actions specified by this AD are intended to prevent early failure of these bushed steel fuselage center-section tie bars, which could result in reduced structural integrity of the wings. Such a condition could lead to loss of control of the airplane.
98-11-01: This amendment supersedes Airworthiness Directive (AD) 97-23-04, which currently requires replacing the fuel tank vent valves with modified fuel tank vent valves on certain Pilatus Aircraft Ltd. (Pilatus) Models PC-12 and PC-12/45 airplanes. This AD retains the fuel tank vent valves replacement required by AD 97-23-04, and requires drilling a 4.8 millimeter (0.1875 inch) hole in each fuel filler cap. This AD also requires inserting a temporary revision in the Pilot's Operating Handbook (POH) that specifies checking to assure that the fuel filler cap hole is clear of ice and foreign objects. This AD is the result of mandatory continued airworthiness information (MCAI) issued by the airworthiness authority for Switzerland. The actions specified by this AD are intended to prevent the fuel tank inward vent valve from freezing, which, if followed by a cold soak at altitude, could result in wing airfoil distortion and structural damage with consequent degradation of the airplane's handling qualities.
2003-05-06: This amendment adopts a new airworthiness directive (AD) that applies to certain Robert E. Rust (R.E. Rust) Models DeHavilland DH.C1 Chipmunk 21, 22, and 22A airplanes. This AD requires you to check the airplane logbook to determine whether certain modifications have been incorporated on the airplane and incorporate the modifications that have not already been accomplished. This AD is the result of the manufacturer performing a design study on the structural integrity of certain parts and reports of service failure of other parts installed on the affected airplanes. The actions specified by this AD are intended to prevent reduced structural integrity in the primary structure of the airplane, which could result in failure of the rudder torque tube, elevator fasteners, and the vertical fin rear spar, or jamming or damage to the elevator. Such failures could lead to loss of control of the airplane.
58-04-01: 58-04-01 DOUGLAS: Applies to All DC3 Series Aircraft Which Have an "Airstair" Type Cabin Door Installation. \n\n\tCompliance required not later than July 1, 1958. \n\n\tThe DC-3 Series aircraft passenger entrance door has been altered by modifiers to hinge the door at the bottom and install steps on the inside of the door, which are used for entering or leaving the aircraft when the door is opened. Numerous instances have occurred wherein the door has opened in flight, or a passenger has inadvertently opened the door and, in some cases, with fatal or near fatal results. \n\n\tIn order to overcome this hazard, it is required that means be provided for safeguarding against inadvertent opening of such doors in flight. CAM 4b.356-2 and -4 outlines the FAA policies which should be followed in complying with this directive.
2012-01-09: We are adopting a new airworthiness directive (AD) for certain The Boeing Company Model 757-200, -200CB, and -300 series airplanes with off-wing escape slide systems installed. This AD was prompted by reports of in-flight loss of the off-wing escape slide. \n\n((Page 3580)) \n\nThis AD requires modifying the door latch fittings and witness mark placards of the off-wing escape slide systems; and for certain airplanes, replacing the bearings and lockbase retainer in the door latch assembly, relocating and adjusting the sensor target and the sensor proximity switch, and testing to ensure positive door locking and corrective action if necessary. For certain airplanes, this AD would also require installing a bumper assembly and placards. We are issuing this AD to prevent the in-flight loss of the off-wing escape slide, which could result in the unavailability of the escape slide during an emergency evacuation. Additionally, the departed slide could cause damage to the fuselage, wing, flaps, or stabilizer, which could degrade flight control.
2003-05-08: This amendment adopts a new airworthiness directive (AD), applicable to certain Dornier Model 328-100 and -300 series airplanes, that requires replacement of certain flight data recorder (FDR) and cockpit voice recorder (CVR) impact switches with certain new impact switches. This action is necessary to prevent the loss of data recorded on the FDR and CVR, which, in the event of an accident, could result in the inability to retrieve data from the FDR and CVR during the accident investigation. This loss of data could hinder the identification of the unsafe condition which caused the accident, and prevent the FAA from developing and mandating actions to prevent additional accidents caused by that same unsafe condition.
89-24-02: 89-24-02 PRATT & WHITNEY: Amendment 39-6365. Applicability: Pratt & Whitney (PW) JT8D-7, -7A, and -7B turbofan engines. Compliance: Required as indicated, unless already accomplished. To prevent engine failure, cowl penetration, fire, or airframe damage associated with a second stage fan disk fracture, accomplish the following: (a) Visually inspect for the presence and protrusion of a spacer within 100 cycles in service (CIS) after the effective date of this AD. NOTE (1) defines the spacer location. If a spacer is found during inspection, accomplish the following: (1) If the spacer radial protrusion is in excess of 0.125 inches, trim the spacer to the fan case inner flow surface. (2) If the spacer radial protrusion is in excess of 0.250 inches over a circumferential length greater than 3 inches, remove the second stage fan disk, first stage stator assembly, and the spacer. Inspect the disk in accordance with paragraphs (d)(1), (d)(2), and (d)(3), within 100 CIS after inspection and thereafter, reinspect the disk in accordance with paragraph (e). (b) Thereafter, visually reinspect for first stage stator spacer protrusion, if a spacer is installed, in accordance with the limits noted in paragraphs (a)(1) and (a)(2), at intervals not to exceed 200 CIS since last inspection (SLI) and until the first stage stator assembly and spacer are removed per paragraph (c) below. (c) Remove the first stage stator assembly and spacer, and install a new or a refurbished first stage stator assembly in accordance with PW JT8D Engine Manual, Part Number (P/N) 481672, at the next engine shop visit, but no later than 4,000 CIS after the effective date of this AD. (d) Inspect all second stage fan disks which have operated in an engine with a spacer installed at the next engine shop visit, but no later than 4,000 CIS after the effective date of this AD, or as required by paragraph (a)(2) above. The inspection shall include the following: (1) Eddy current inspect disk pin holes and remove from service all disks defined as not serviceable in accordance with the instructions in the APPENDIX (United Airlines Eddy Current Non-Destructive Test Procedure Number MJ-70-NDT-352, dated June 6, 1989) to this AD. (2) Visually inspect the inner surface of the disk pin hole for evidence of galling or other surface damage. Reject disks with damage in excess of 0.003 inches deep. (3) Dimensionally inspect the disk pin hole diameters. Reject disks if any disk pin hole diameter exceeds 0.5498 inches (Reference PW JT8D Engine Manual, Section 72-33-04, Inspection -01, Page 801, Reference 222). (e) Thereafter, reinspect second stage fan disks in accordance with paragraphs (d)(1), (d)(2), and (d)(3) above, at intervals not to exceed 4,000 CIS SLI if the disk operated in an engine with a spacer radial protrusion in excess of the limits established in paragraph (a)(2) above. (f) If a first stage stator spaceris found during the initial visual inspection, report the following information in writing within 30 days of the inspection to the Manager, Engine Certification Office, Engine and Propeller Directorate, Aircraft Certification Service, Federal Aviation Administration, 12 New England Executive Park, Burlington, Massachusetts 01803; Telex Number 949301 FAANE BURL: (1) Engine serial number (S/N). (2) Inspection date. (3) First stage stator spacer maximum radial protrusion and circumferential length of protrusion. (4) Second stage fan disk P/N and S/N. (g) Report the following information in writing within 30 days of the second stage fan disk inspection to the Manager, Engine Certification Office, Engine and Propeller Directorate, Aircraft Certification Service, Federal Aviation Administration, 12 New England Executive Park, Burlington, Massachusetts 01803; Telex Number 949301 FAANE BURL: (1) Engine serial number (S/N). (2) Inspection date. (3)Second stage fan disk P/N and S/N. (4) Second stage fan disk total time and cycles (if estimate, so note). (5) Second stage fan disk time and cycles since installation. (6) Second stage fan disk inspection results for rejected disks (specify rejection criteria used). Information collection requirements contained in this regulation (Section 39.13) have been approved by the Office of Management and Budget (OMB) under the provisions of the Paperwork Reduction Act of 1980 (Pub. L. 96-511) and have been assigned OMB Control Number 2120-0056. (h) Records showing that United Airlines (UAL) has not performed maintenance on the engine may be used in lieu of the visual inspection requirements of paragraph (a) above to verify the absence of the spacer, provided the operator's FAA Airworthiness Inspector is supplied with a complete maintenance history of the engine and determines that UAL has never maintained, overhauled or altered the engine after October 10, 1972.NOTES: (1) The location where the first stage stator spacer would be installed is shown in the PW JT8D Engine Manual, P/N 481672, Section 72-33-65, Repair-00, Page 901/902, Figure 901, Index 3. (2) Engine shop visit is defined as the input of an engine to a repair shop with low pressure compressor rotor overhaul capability where the subsequent engine maintenance entails the following: (a) Separation of a major engine flange (lettered or numbered) other than flanges mating with major sections of the nacelle or reverser. Separation of flanges purely for purposes of shipment, without subsequent internal maintenance, is not a "shop visit." (b) Removal of a disk, hub, or spool. (i) Aircraft may be ferried in accordance with the provisions of FAR 21.197 and 21.199 to a base where the AD can be accomplished. (j) Upon submission of substantiating data by an owner or operator through an FAA Airworthiness Inspector, an alternate method of compliance with therequirements of this AD or adjustments to the compliance times specified in this AD, may be approved by the Manager, Engine Certification Office, ANE-140, Engine and Propeller Directorate, Aircraft Certification Service, Federal Aviation Administration, 12 New England Executive Park, Burlington, Massachusetts 01803. This amendment (39-6365, AD 89-24-02) becomes effective on November 13, 1989. 89-24-02 APPENDIX NOTE: United Airlines Eddy Current Non-Destructive Test Procedure Number MJ-70-NDT-352, dated June 6, 1989, pertain to these inspections.
2018-03-03: We are adopting a new airworthiness directive (AD) for certain Textron Aviation Inc. Models 401, 401A, 401B, 402, 402A, 402B, 402C, 411, 411A, 414, 414A 421, 421A, 421B, 421C, and 425 airplanes. This AD requires repetitively inspecting the left and the right forward lower carry through spar cap for cracks and replacing the carry through spar if cracks are found. This AD was prompted by a report of a fully cracked lower forward carry through spar cap found on an affected airplane. We are issuing this AD to address the unsafe condition on these products.
2012-01-07: We are adopting a new airworthiness directive (AD) for BRP-- POWERTRAIN GMBH & CO KG Rotax 914 F2, 914 F3, and 914 F4 reciprocating engines. 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 isolated manufacturing deviations reportedly found on the threads of a certain batch of fuel pressure regulators, part number (P/N) 887130, installed on Rotax 914 F series engines, which could result in fuel leakage during engine operation. We are issuing this AD to prevent fuel leaks, which could result in an in-flight fire and damage to the aircraft.
57-14-03: 57-14-03 VICKERS: Applies to All Viscount 700 Series Aircraft. Compliance required as indicated. Investigation of a recent case resulting in asymmetric flaps occurring just prior to touchdown shows excessive end float of the flap torque shaft can occur between the flap gearbox and No. 1 flap unit port and starboard. Following action considered essential by Vickers with which the FAA concurs and considers mandatory. 1. At next daily inspection unscrew flap universal joint cap port and starboard and check engagement of trunnion blocks within universal joint body of the torque tube. With trunnion block journals facing fore and aft ensure maximum outboard float of torque shaft is obtained by gentle tapping if necessary. Where trunnion blocks do not protrude from body more than 0.4 of an inch, aircraft may continue to fly but corrective action (item 3.) must be taken within 300 hours flying. 2. If trunnion blocks protrude more than 0.4 of an inch, corrective action (item 3.) must be taken within 25 hours flying time, or if trunnion blocks protrude 0.52 of an inch or more, corrective action must be taken prior to further flight. 3. Set torque shaft with trunnion blocks flush with end of universal body and prepare and fit tubular fiber or fluon (teflon equivalent) distance piece to suit dimension between inboard vertical face of No. 1 flap unit chain box and adjacent end of torque tube. Internal diameter of distance piece 1.52 inches with suitable recess to clear greaser on chain box if necessary. Before removal, splined shaft must be marked to ensure correct reassembly. On completion of inspection torque tubes should be moved toward gearbox as far as end float permits.