Results
2005-10-10: The FAA is adopting a new airworthiness directive (AD) for certain Bombardier Model CL-600-2B19 (Regional Jet Series 100 & 440) airplanes. This AD requires revising the Airworthiness Limitations section of the Instructions for Continued Airworthiness of the Canadair Regional Jet Maintenance Requirements Manual by incorporating new repetitive detailed inspections of the secondary load path indicator for the horizontal stabilizer trim actuator (HSTA). This AD is prompted by a report of a potential failure of the horizontal stabilizer trim actuator (HSTA) secondary nut in conjunction with a latent failure of the HSTA primary load path discovered during sampling program activities. We are issuing this AD to detect and correct latent failure of the primary load path of the HSTA, which, in conjunction with a failure of the HSTA secondary nut, could result in loss of horizontal trim control and consequent reduced controllability of the airplane.
70-25-09: 70-25-09 AEROSTAR: Amdt. 39-1127. Applies to Model 601, S/N's 61-001 through 61- 0070, and to all Model 600 airplanes equipped with the Aerostar Model 601 oxygen system. Compliance required within the next 10 hours time in service after the effective date of this AD unless already accomplished. To prevent possible short circuiting of the microphone jack connection by contact with the oxygen outlet receptacle due to their proximity to each other, accomplish the relocation specified in Aerostar Aircraft Corporation Service Bulletin No. S.B. 600-26 dated November 6, 1970, or later FAA-approved revisions, or other equivalent modification approved by the Chief, Engineering and Manufacturing Branch, Southwest Region, FAA. This amendment becomes effective to all known owners of Aerostar Model 601 airplanes and Model 600 airplanes equipped with the Aerostar Model 601 oxygen system upon receipt of individual copies mailed December 8, 1970 and to all other persons on December18, 1970.
96-12-07: This amendment supersedes an existing airworthiness directive (AD), applicable to Teledyne Continental Motors (TCM) (formerly Bendix) S-20, S-1200, D-2000, and D-3000 series magnetos equipped with impulse couplings, that currently requires inspections for wear, and replacement, if necessary, of the impulse coupling assemblies. This amendment requires replacement, if necessary, of worn riveted impulse coupling assemblies with serviceable riveted impulse couplings or snap ring impulse couplings. This amendment is prompted by the availability of an improved design for the impulse coupling assembly. The actions specified by this AD are intended to prevent magneto failure and subsequent engine failure.
2005-10-08: The FAA is adopting a new airworthiness directive (AD) for certain Bombardier Model DHC-8-102, -103, -106, -201, -202, -301, -311, and -315 airplanes. This AD requires operators to install torque tube catchers on the control columns of the flight controls. This AD is prompted by the discovery that a single malfunction of the torque tube could result in both flight control columns being supported by only one self-aligning bearing. We are issuing this AD to prevent the torque tube from fouling against the underfloor control cables, which could result in reduced controllability of the airplane.
75-11-01: 75-11-01 CESSNA: Amendment 39-2204 as amended by Amendment 39-2548. Applies to all Cessna Model 320 Series airplanes. Compliance: Required as indicated, unless already accomplished. To detect and correct fuel line chafing or fuel leaks behind the engine firewalls, within 100 hours' time in service after the effective date of this AD, accomplish the following: A) Visually inspect fuel lines routed in the area behind the engine firewalls and the front wing spars for leaks or chafing in accordance with Cessna Service Letter ME70-39, Revision I, dated April 4, 1975, or subsequent revisions. B) If as a result of the inspection required by Paragraph A, fuel line leaks or damage is found, prior to further flight, replace the affected line with an airworthy part in accordance with Cessna Service Kit SK402-8C dated February 20, 1975, or subsequent revisions. C) On Models 320D, 320E and 320F airplanes, in addition to the inspection required in Paragraph A, add additional supporting clamps to the crossover fuel lines in accordance with Cessna Service Kit SK402-8C, dated February 20, 1975, or subsequent revisions. D) Any equivalent method of compliance with this AD must be approved by the Chief, Engineering and Manufacturing Branch, FAA, Central Region. Amendment 39-2204 became effective May 20, 1975. This amendment 39-2548 becomes effective March 22, 1976.
2001-11-08: This amendment supersedes an existing airworthiness directive (AD), applicable to certain Boeing Model 747-400, 757-200, 767-200, and 767-300 series airplanes, that currently requires repetitive checks to detect certain failures in the warning electronic unit (WEU) or modular avionic warning electronic assembly (MAWEA); repetitive tests to detect any failure of tactile, visual, or aural alerts generated by the WEU or MAWEA; and corrective action, if necessary. This amendment makes these requirements applicable to other airplanes on which the defective power supplies may be installed, eliminates the repetitive tests for certain airplanes, and increases the interval for the repetitive tests for certain other airplanes. This amendment also requires replacing any subject power supply in the WEU or MAWEA with a new, modified, or serviceable power supply. The actions specified by this AD are intended to prevent failure of the WEU or MAWEA power supplies, which could result in loss of visual, aural, and tactile alerts to the flightcrew. Absence of such alerts could result in the flightcrew being unaware that an immediate or appropriate action should be taken in the event of an unsafe condition.
59-05-04: 59-05-04 ERCOUPE: Applies to All Models 415-C, 415-CD, 415-D, E and G. Compliance to be accomplished within the next 100 hours of operation. Frequent failures of the rear spar center section have been found on Ercoupe Model aircraft. These failures follow the same pattern in that the rear spar P/N 415-13048 L/R failed due to cracking of the upper flange in the area of the intersection of the rear spar with the fuselage side on either the right or left spar assembly. Repairs made in the field with gusset plates have been found to be only partially satisfactory and in most instances did not keep the crack from progressing into the spar web. This damage to the spar has been attributed to the following: (1) Rough landings coupled with a lack of fluid in the oleo struts. (2) Taxiing at high speeds over rough terrain. (3) A combination of (1) and (2) with the structure weakened by corrosion due to no protective coating of the spar. In view of the above, it is mandatory that therear spar on Forney (Ercoupe) aircraft be inspected and action taken as follows: (1) If no damage or cracks are found, the spar must be reinforced by stiffener angle P/N F-13109 or equivalent. The spar may be considered satisfactory if previously reinforced with P/N 415-13108 or equivalent. (2) If damage or crack exists but does not extend into the spar web, a repair may be made by the addition of stiffener P/N F-13109 or equivalent provided an inspection every 100 hours of service life thereafter discloses no further progressive damage. If damage is found to progress, then a new spar and stiffener must be installed. If damage or crack extends into the spar web, the spar must be replaced. (3) If a new spar and stiffener is installed, the 100-hour inspection requirement in (2) above may be eliminated. (Forney Manufacturing Company, Aviation Division, Fort Collins, Colorado, Service Memorandum 53A supersedes Service Memorandum 53 and covers this same subject.) This supersedes AD 57-13-03.
75-23-07: 75-23-07 CESSNA: Amendment 39-2418. Applies to Models 310Q/T310Q (Serial Numbers 310Q0401 thru 310Q1160) and 310R/T310R (Serial Numbers 310R0001 thru 310R0330) airplanes. Compliance: Required as indicated, unless already accomplished. To assure proper operation of the emergency exit window, within the next 50 hours' time in service after the effective date of this AD, accomplish the window modification, screw inspection, trim modification and placard installation, as applicable, in accordance with Cessna Service Letter ME75-26 or later approved revision or by any equivalent method of compliance approved by the Chief, Engineering and Manufacturing Branch, FAA, Central Region. This amendment becomes effective November 13, 1975.
2005-10-03: The FAA is adopting a new airworthiness directive (AD) for certain Boeing Model 777-200 and -300 series airplanes. This AD requires modification of the operational program software (OPS) of the air data inertial reference unit (ADIRU). This AD is prompted by a report of the display of erroneous heading information to the pilot due to a defect in the OPS of the ADIRU. We are issuing this AD to prevent the display of erroneous heading information to the pilot, which could result in loss of the main sources of attitude data, consequent high pilot workload, and subsequent deviation from the intended flight path.
58-16-01: 58-16-01 PIPER: Applies to Model PA-20 Serial Numbers 20-1 to 20-1121 Inclusive, and Model PA-22 Serial Numbers 22-1 to 22-6087 Inclusive, That Have Cigar Lighters Installed. Compliance required within next 100 hours of operation. To preclude the possibility of blowing the master fuses, due to a short circuit caused by a faulty cigar lighter element, install a 15-ampere standard fuse, Bussman No. AGC-15 or equivalent, in the wire between the cigar lighter and the ammeter. (Piper Service Bulletin Number 163A covers the same subject.)
2010-17-12: The FAA is superseding an existing airworthiness directive (AD) for the products listed above. This AD results from mandatory continuing airworthiness information (MCAI) issued 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: Strip results from some of the engines listed in the applicability section of this AD revealed excessively corroded low- pressure turbine disks stage 2 and stage 3. The corrosion is considered to be caused by the environment in which these engines are operated. Following a life assessment based on the strip findings it is concluded that inspections for corrosion attack are required. The action specified by this European Aviation Safety Agency (EASA) AD 2008-0122 was intended to avoid a failure of a low- pressure turbine disk stage 2 or stage 3 due to potential corrosion problems which could result in uncontained engine failure and damage to theairplane. It has been later realized that the same unsafe condition could potentially occur on more serial numbers for the Tay 650-15 engines and on the Tay 651-54 engines. This AD, superseding EASA AD 2008-0122, retaining its requirements, is therefore issued to expand the Applicability in adding further engine serial numbers for the Tay 650-15 engines and in adding the Tay 651-54 engines. We are issuing this AD to detect corrosion that could cause the stage 2 or stage 3 disk of the LP turbine to fail and result in an uncontained failure of the engine.
69-05-04: 69-05-04 SCHLEICHER: Amdt. 39-730. Applies to Schleicher Model ASK-13 gliders, Serial Numbers 13000 through 13104, 13108, 13109, except Serial Numbers 13071 and 13096. Compliance required within the next 100 hours' time in service after the effective date of this AD, unless already accomplished. To prevent the landing gear end buffer plate from slipping inside the rubber buffer, replace the 2.76-inch diameter buffer plate located on the left and right landing gear with a 3.55- inch diameter buffer plate, in accordance with Schleicher Modification No. 3, dated September 4, 1968, or later LBA-approved issue or an FAA-approved equivalent. This amendment becomes effective April 5, 1969.
2005-10-04: This amendment adopts a new airworthiness directive (AD), applicable to certain Airbus Model A319, A320, and A321 series airplanes. This AD requires repetitive inspections of the left- and right-side main landing gear (MLG) side-stay cuff lugs and down-lock spring attachments for evidence of cracked or fractured side-stay cuff lugs or down-lock spring attachments, and repair if necessary. This AD also provides for optional terminating action for the repetitive inspections. This action is necessary to prevent failure of the MLG side-stay cuff lugs or down-lock spring attachments, which could result in improper down-lock of the MLG during a freefall extension, and possible collapse of the MLG. This action is intended to address the identified unsafe condition.
57-13-08: 57-13-08 PIPER: Applies to Model PA-23 Serial Numbers 23-1 to 23-729, Inclusive. Compliance required by September 1, 1957. To prevent inadvertent retraction of the landing gear due to malfunction of the landing gear hydraulic system, install an antiretraction device (Piper Kit No. 754140 or equivalent) that will prevent start of the retraction cycle and consequent landing gear collapse while the aircraft is on the ground. (Piper Service Bulletin No. 145 of December 31, 1956, covers this subject.)
97-11-06: This amendment adopts a new airworthiness directive (AD) that is applicable to certain Pratt & Whitney PW4164 and PW4168 series turbofan engines. This action requires initial and repetitive visual inspections of the fan blades for surface damage and cracks, initial and repetitive lubrication of the fan blade part span shrouds, a one time ultrasonic inspection (UI) of the fan blade root attachment area for cracks, and a one time fan blade root attachment front corner radii inspection for proper dimension. Also, this AD requires visual inspection of the fan blades and removal of fan blades damaged by a bird strike as well as removal of blades immediately adjacent to damaged blades. In addition, this AD requires installation of an improved fan blade assembly as terminating action to the inspection requirements of this AD. This amendment is prompted by a report of a high N1 rotor imbalance and liberation of the fan containment system causing loss of structural support of theengine inlet cowl, following loss of a fan blade during a test. The actions specified in this AD are intended to prevent fan blade failure and separation at the root section, which could result in high N1 rotor imbalance, and liberation of the fan containment system, which can hazard the aircraft.
71-24-05: 71-24-05 PRATT & WHITNEY: Amendment 39-1137 as amended by Amendment 39-1847. Applies to all Pratt & Whitney Aircraft JT12A series turbojet and JFTD12A series turboshaft engines which incorporate any of the compressor rotor discs with serial numbers listed in Pratt & Whitney Aircraft Turbojet Engine Service Bulletin No. 3421 dated 4 August 1971 as amended by Revision No. 3, dated December 10, 1973. Compliance required as indicated. (a) To preclude compressor rotor disc failure as the result of reduced life from traces of lead - (1) For those discs listed in Pratt & Whitney Aircraft turbojet Engine Service Bulletin No. 3421, dated August 4, 1971, remove from service the listed discs prior to reaching the revised life limit or within the next 30 cycles in service after November 26, 1971, whichever comes later. (2) For those discs not listed in the above Service Bulletin but listed in Revision No. 3, dated December 10, 1973, remove from service the listed discs prior to reaching the revised life limit or within the next 30 cycles in service after the effective date of this amendment, whichever comes later. The manufacturer's Service Bulletin identified and described in this directive is incorporated herein and made a part hereof pursuant to 5 U.S.C. 552(a)(1). All persons affected by this directive who have not already received this document from the manufacturer may obtain copies upon request from Pratt & Whitney Aircraft Division of United Aircraft Corporation, East Hartford, Connecticut 06108. This document may also be examined at the FAA, New England Region, 12 New England Executive Park, Burlington, Massachusetts or at the FAA Headquarters, 800 Independence Avenue, S.W., Washington, D.C. A historical file on the AD which includes the incorporated material in full is maintained by the FAA in its headquarters in Washington, D.C., and in the New England Region. Upon submission of substantiating data through an FAA Maintenance Inspector by an owner or operator to the Chief, Engineering and Manufacturing Branch, FAA New England Region, compliance time may be adjusted. The incorporation by reference provision in this document was approved by the Director of the Federal Register on June 19, 1967. Amendment 39-1337 was effective November 26, 1971. This Amendment 39-1847 becomes effective May 31, 1974.
2005-10-02: The FAA is adopting a new airworthiness directive (AD) for all Dornier Model 328-300 series airplanes. This AD requires installing an additional mounting angle for the respective de-icing pipes at rib 9 in the leading edge area of the left- and right-hand wings. This AD is prompted by chafed de-icing lines in the wing leading edge area. We are issuing this AD to prevent chafing of the de-icing lines, which could result in a reduction in functionality of the anti-ice system, and possibly reduced controllability and performance of the airplane in icing conditions.
52-07-03: 52-07-03 PIPER: Applies to All Models J3 Series and PA-11 Aircraft. Compliance required prior to November 1, 1952. 1. Revise the present front and rear wing lift strut as follows: (a) Cut 1/8 inch from lower end of barrel assembly and strut end. (b) Remove the flanges and weld metal which extends through upper and lower strut surface, taking care not to damage struts. (c) Remove barrel assembly from strut by applying a slight pull through an old forked fitting. (d) Inspect strut for (internal) rust, bending, excessive wear, or other damage, and replace strut if necessary. (e) Clean surplus old weld or rough edges from slots in the strut ends. (f) Increase depth of these slots (approximately 1/8 inch) so the new barrel's lower flange will extend 3/32 inch beyond the strut end. (g) Insert new plate and barrel assembly, P/N 12521, with its centerline parallel with the centerline of the strut. (h) Weld fitting into strut aroundthe slots and lower strut end. (i) Refinish strut. (j) Install new forked fitting, P/N 13710 and AN 315-7R locknut. (k) Due to the importance of this rework, care must be exercised and it is recommended that only competent welders with extensive recent welding experience should undertake this work. 2. After installing reworked lift struts rerig the aircraft in accordance with appropriate Piper Service Manual Instructions. 3. Placard all lift struts, "No step". 4. Compliance with AD 51-15-01, covering the periodic inspection of lower lift strut fork fittings, P/N 11281, may be discontinued after compliance with this airworthiness directive. (Piper Service Bulletin No. 120, dated March 28, 1952, covers this same subject.)
53-21-02: 53-21-02 GRUMMAN: Applies to All Model G-21A (Converted OA-9, JRF-1 Through JRF-5 and JRF-6B) Aircraft. Compliance required as indicated. 1. Inspect the threaded portion of the horizontal stabilizer strut lower adjustable end fitting P/N 12561-3, by a magnetic particle inspection method, as soon as practicable, but not later than November 15, 1953, and at 1,000-hour intervals thereafter. Replace fitting if crack is found. 2. Replace these fittings every 3,200 hours. If 3,200 hours is reached before the first inspection, fittings may be used for 50 hours after this inspection provided no cracks are found. (Grumman Aircraft Engineering Corp. Customer Bulletin G-21A No. 3, dated March 20, 1953, covers this same subject.)
59-16-05: 59-16-05\tBOEING: Applies to 707-100 series aircraft with the following serial numbers: Model 707-121 serial numbers 17586 through 17591, Model 707-124 serial number 17609, Model 707-123 serial numbers 17628 through 17643, Model 707-131 serial numbers 17659 through 17672, Model VC-137A serial numbers 17925 through 17927. \n\tCompliance required not later than August 21, 1959. \n\tAs a result of complete loss of fluid during service operation of the utility hydraulic system, primarily due to failure of engine driven hydraulic pump the following must be accomplished: \n\t(a)\tInstall new pump, Vickers No. AS-61689-L-2E, in place of the AS-61689-L-2B or - 2C, or install pump external by-pass valve No. A-90073-Y6 with the -2B or -2C pump. If the pump external by-pass valve is installed the shaft seal on each hydraulic pump must be replaced at the same time. \n\t(b)\tInstall return line filter. \n\tBoeing Service Bulletin No. 379 and Vickers Service Letter dated June 17, 1959, pertain to item (a). Boeing Service Bulletins Nos. 69 and 213 pertain to item (b).
2005-10-05: The FAA is adopting a new airworthiness directive (AD) for CFM International CFM56-5, -5B, and -5C series turbofan engines. This AD requires removing certain part number (P/N) air turbine starters from service. This AD results from several reports of uncontained failures of air turbine starters where high-energy particles were not contained within the containment feature of the starter. We are issuing this AD to prevent uncontained failures of air turbine starters, which could result in damage to the airplane.
74-10-08: 74-10-08 BOEING: Amendment 39-1836 as amended by Amendment 39-2073. Applies to all model 727 series airplanes certificated in all categories. Compliance required as indicated. \n\t(A)\tUnless already accomplished on airplanes which have been delivered after September 30, 1973, or which have had new horizontal stabilizer hinge pins, P/N 69-14410, installed since that time, conduct the inspection and modification of paragraph (C) below, within the next 15 days after the effective date of this AD. \n\t(B)\tUnless already accomplished on all other airplanes, conduct the inspection and modification of paragraph (C) below, within the next 6 months after the effective date of this AD. \n\t(C)\tInspect the horizontal stabilizer hinge pins for integrity, replace as necessary, and install threaded retention rods, P/N 69-67076, or equivalent, in accordance with Boeing Alert Service Bulletin 727-55-59, or FAA approved revisions, or in a manner approved by the Chief, Engineering and Manufacturing Branch, FAA Northwest Region. \n\t(D)\tIf a threaded rod, P/N 69-67076-2, or an equivalent fabricated rod made from threaded rod NAS 1454-( )-( ), or any other rod with a Class 2 thread has been installed, unless already accomplished, conduct, before September 6, 1975, the hinge pin retainer nut torque inspection in accordance with Paragraph III, Part II of Boeing Alert Service Bulletin No. 727-55- 59, Revision 2, or later FAA approved revisions, or in a manner approved by the Chief, Engineering and Manufacturing Branch, FAA Northwest Region. \n\t\tIf the torque required to rotate the self-locking nut is less than 30 inch-pounds, replace the rod in accordance with Boeing Alert Service Bulletin No. 727-55-59, Revision 3, or later FAA approved revisions, or in a manner approved by the Chief, Engineering and Manufacturing Branch, FAA Northwest Region. \n\tThe 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). All persons affected by this directive who have not already received these documents may obtain copies upon request to The Boeing Company, P. O. Box 3707, Seattle, Washington 98124. These documents may also be examined at FAA Northwest Region, Boeing Field, Seattle, Washington. \n\n\tAmendment 39-1836 became effective on May 10, 1974. \n\tThis Amendment 39-2073 becomes effective on February 27, 1975.
54-26-02: 54-26-02 VEST (ERCO): Applies to All Ercoupe Model 415 Series Aircraft and Models E and G. Compliance required as indicated. As a result of continual fraying and failure of control cables P/N 415-52148 or P/N 415-52172 in the control column assembly where they wrap around the control quadrant P/N 415-52130 or P/N 415-52122 the following inspection must be conducted until such time as a control quadrant is installed which is considered satisfactory by the Administrator: After every 100 hours of operation remove control cables P/N 415-52148 or P/N 415-52172 and inspect them for any signs or indications of fraying or failure. Replace any cables which are not found to be in perfect condition. It is important that the cables be removed for the inspection since it has been found that inspection of the cables while in place will not always reveal defects. Also determine whether the aileron stop screw may be bearing on the cable, and, if so, it should be replaced by new stop boltErco P/N 415-52164-2. Modifications approved by the FAA which are believed to eliminate the fraying difficulties are described in the following data: 1. Drawing No. 514, change "A", Met-Co-Aire Co., Fullerton Municipal Airport, Fullerton, Calif.; 2. Drawing No. New 101, change "A," J.V. Newman, Bates Aviation Inc., Hawthorne Municipal Airport, Hawthorne, Calif. 3. Drawing No. 12, dated November 1, 1954, Ed's Airmotive, 430 Windsor Way, Renton 2, Wash.; 4. Drawing No. 415-52137, change "1," dated February 21, 1955, Vest Aircraft Parts Division, Denver, Colo. When one of these or an equivalent FAA-approved modification has been installed, the special 100-hour inspection outlined above may be dispensed with and normal inspection period resumed. Rigging of controls should follow the process outlined in Ercoupe Service Department Bulletin No. 13 and Ercoupe Service Department Memorandum No. 35. This supersedes AD 47-42-21.
2004-25-16 R1: The FAA is revising Airworthiness Directive (AD) 2004-25-16, which applies to aircraft equipped with a fuel regulator shutoff valve part number (P/N) 14D11, A14D11, B14D11, C14D11, 23D04, A23D04, B23D04, C23D04, or P23D04 used with B1500, B2030, B2500, B3040, B3500, B4050, or B4500 B-Series combustion heaters. AD 2004-25-16 currently requires you to repetitively inspect the fuel regulator shutoff valve (visually or by pressure test) for fuel leakage and replace the fuel regulator shutoff valve with an improved design replacement part with a manufacturer's date code of 02/02 or later if fuel leakage is found. AD 2004-25-16 also allows you to disable the heater as an alternative method of compliance. Since we issued AD 2004-25-16, we received several comments requesting a revision to paragraph (e)(2). Consequently, this AD retains the actions required in AD 2004-25-16 and revises the requirements in paragraph (e)(2) to remove a required action. We are issuing this AD to preventfailure of the fuel regulator shutoff valve, which could result in fuel leakage in aircraft with these combustion heaters. This failure could result in an aircraft fire. DATES: This AD becomes effective on June 20, 2005. On January 5, 2005 (69 FR 75228, December 16, 2004), the Director of the Federal Register approved the incorporation by reference of Kelly Aerospace Power Systems Service Bulletin No. A-107A, Issue Date: September 6, 2002; and Piper Vendor Service Publication VSP-150, dated January 31, 2003.
52-05-02: 52-05-02 MARTIN: Applies to All Models 202 and 202A Aircraft. Compliance required as indicated. Due to a reported occurrence of cracks in the center wing rear spar lower chord fitting at the Station 187 rib, the following shall be accomplished: A. Inspect within the next 100 hours. Inspect the fittings (P/N 2021U44473 and 2021U44474) with a 10-power magnifying glass after removal of the paint with a solvent. Pay particular attention to the intersection of the spar leg with the other legs of the fittings. B. If cracks are discovered in the base or extending into the base of a fitting, the part must be replaced. C. If cracks are found in the vertical legs only, the part can either be replaced or remain installed in the airplane. If remaining installed, the fitting must be inspected every 85 hours in accordance with items A and B. Other inspection intervals may be approved based on the evaluation of the actual crack location by the manufacturer. D. For fittings that do not show any cracks, loosen the two bolts through the fitting, the spar stiffener and the spar chord tang. Also loosen the two spar web splice bolts through the fitting, the spar web stiffeners and rib 187 web. If any gap appears between the fitting and its mating surfaces, install shims so as to reduce this gap to less than 0.010 inch. E. New parts installed shall be shimmed in accordance with item D. (Glenn L. Martin Service Instruction Letter No. 17 covers this same subject.)