Results
2001-26-51: This document publishes in the Federal Register an amendment adopting airworthiness directive (AD) 2001-26-51 that was sent previously to all known U.S. owners and operators of certain Bombardier Model CL-600-2B19 series airplanes by individual notices. This AD requires deactivation of the center tank fuel transfer shutoff valves by opening circuit breakers and installing a circuit breaker lock ring and disconnecting and stowing the electrical wiring, replacing certain valves with valves having a different part number, reconnecting certain circuit breaker wires, removing lock rings, and resetting the associated circuit breakers. For certain airplanes, this AD requires an AFM revision to prohibit operation with more than 200 pounds of fuel in the center fuel tank. This AD also has a provision for operating other airplanes with the center fuel tank full and with both fuel transfer shutoff valves inoperative. This action 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 ignition of fuel vapor in the center wing tank and consequent fire and explosion.
2001-26-21: This amendment adopts a new airworthiness directive (AD), applicable to certain Airbus Model A319, A320, and A321 series airplanes, that requires replacement of the low-pressure solenoid valve for the crew oxygen supply with a modified valve. This action is necessary to prevent faulty operation of the low-pressure solenoid valve for the crew oxygen supply, which could prevent oxygen from being supplied to the airplane crew when needed, such as in the event of smoke in the cabin or rapid depressurization of the airplane. This action is intended to address the identified unsafe condition.
2001-26-22: This amendment adopts a new airworthiness directive (AD), applicable to certain BAE Systems (Operations) Limited Model Avro 146-RJ series airplanes, that requires a one-time inspection of the S4 and S5 static pipes of the pitot static system for discrepancies, and follow-on corrective actions, if necessary. This action is necessary to prevent failure of the S4 and S5 static pipes and consequent failure of the maximum differential pressure protection for the airplane, which could lead to the fuselage of the airplane being overstressed and result in reduced structural integrity of the airplane. This action is intended to address the identified unsafe condition.
2001-26-05: This amendment adopts a new airworthiness directive (AD) that is applicable to certain Hamilton Sundstrand model 247F propellers. This action requires a one-time rework of certain model 247F propellers by removing all four propeller blades from service, replacing those blades with serviceable propeller blades, and marking the propeller with a new part number. This amendment is prompted by nine reports of the blades partially slipping at the bond joint between the blade tulip and the composite blade airfoil interface. The actions specified in this AD are intended to prevent the loss of a propeller blade, which may result in loss of airplane control.
2001-26-09: This amendment adopts a new airworthiness directive (AD), applicable to certain Boeing Model 767-200 series airplanes, that requires a one-time inspection of the water line heater tape where it passes close to the duct assemblies of the air distribution system for the flight compartment to detect damage, and follow-on actions. This amendment also requires eventual replacement of certain duct assemblies or foam insulation on those duct assemblies with new duct assemblies or improved foam insulation. This action is necessary to prevent ignition of foam insulation on the air distribution ducts, which could result in a fire in the airplane. This action is intended to address the identified unsafe condition.
97-03-02: This amendment adopts a new airworthiness directive (AD) that applies to Glasflugel Models H301 "Libelle", H301B "Libelle", Standard "Libelle", Standard Libelle 201B, Club Libelle 205, and Kestrel sailplanes. This AD requires measuring and adjusting the control surface weight and static moment, and inserting amendments into the Glasflugel Flight and Service Manual. This AD results from reports of considerable variation of the weight and static moment of the control surface on the affected sailplanes found during repair or repainting of the control surface. The actions specified by this AD are intended to prevent sailplane flutter because the weight and static moment of the control surface are not within certain limits, which could result in flutter and subsequent loss of control of the sailplane.
2001-25-04: This amendment adopts a new airworthiness directive (AD), that is applicable to Honeywell International Inc. (formerly AlliedSignal Inc. and Textron Lycoming) Models LTS101-600A-2 and LTS101-600A-3 turboshaft engines; and LTP101-600A-1A and LTP101-700A-1A turboprop engines. This amendment requires replacing certain fuel controls that have beryllium-copper bellows with improved fuel controls that incorporate Inconel 718 stainless steel welded bellows. This amendment is prompted by a report of an uncommanded power loss on a Textron Lycoming LTS101 engine due to a corrosion damaged fuel control bellows. The actions specified by this AD are intended to prevent the engine from reducing the fuel flow to minimum flow resulting in an uncommanded power loss.
2001-24-32: This amendment adopts a new airworthiness directive (AD), applicable to certain Boeing Model 747-100, 747-200B, 747-200C, 747-200F, 747SP, and 747SR series airplanes. This AD requires a one-time inspection for chafing of certain wire bundles behind the flight engineer's panel; repairs, if necessary; and a modification to reroute a certain electrical wire bundle to ensure sufficient clearance between that wire bundle and an adjacent flood light support bracket. This action is necessary to prevent chafing of certain electrical wire bundles, which could result in smoke in the cockpit, and uncommanded discharge of fire extinguishing bottles for the No. 4 engine and consequent reduction of the ability to fight a fire in the No. 4 engine. This action is intended to address the identified unsafe condition.
51-16-01: 51-16-01\tBELLANCA: Applies to All Models 14-13 and 14-13-2 Airplanes. \n\n\tCompliance required within the next 25 hours of operation, but not later than August 1, 1951. \n\n\tAs a result of a recent failure of the elevator trim tab in flight, the modification of the trim tab attachment to the elevator as shown in Figure 1 should be made. \n\n\n\n\nFIGURE 1 \n\n\t(Bellanca Service Bulletin No. 14, Models 14-13 and 14-13-2, covers this same subject.)
66-01-03: 66-01-03 PILATUS: Amdt. 39-173, Part 39, Federal Register December 24, 1965. Applies to Model PC-6 Series Airplanes, Serial Numbers 515, 522, and 524 through 580. Compliance required as indicated, unless already accomplished. To prevent further instances of fuel flow restriction, accomplish the following: (a) Within the next 10 hours' time in service after the effective date of this AD, inspect fuel shutoff valve P/N 321-ITX 6D for correct installation of the valve plug in accordance with Pilatus Service Bulletin No. 36, dated September 1965, or later Swiss Federal Air Office- approved revision. If the valve plug protrudes more than 2mm. (0.078 inch), before further flight, replace the valve with a new valve P/N 6238.124. (b) Within the next 60 hours' time in service after the effective date of this AD, replace fuel shutoff valve P/N 321-ITX 6D with a new valve P/N 6238.124, in accordance with Pilatus Service Bulletin No. 36, dated September 1965, or later Swiss Federal Air Office- approved revision.
69-19-06: 69-19-06 GENERAL DYNAMICS: Amdt. 39-842. Applies to all Model 22 Aircraft equipped with axle beam P/N 9729-68-1 and Model 22M Aircraft equipped with axle beam P/N 1057-68-1. Compliance required within the next 2000 hours' time in service after the effective date of this AD or before the accumulation of 9000 hours' total time in service, whichever occurs later, unless already accomplished. Several failures of the main landing gear axle beam have been attributed to cracks originating near the center jack pad on the beam lower surface. The crack then progresses upward until complete failure of the beam occurs at a point above the axle beam pivot pin. The initial crack in the beam develops due to stress corrosion or hydrogen embrittlement. To prevent further failures of this nature, accomplish the following or an equivalent approved by the Chief, Aircraft Engineering Division, FAA Western Region. (a) Inspect and rework each Model 22 Aircraft axle beam assembly P/N 9729-68-1 in accordance with General Dynamics/Convair 880 Service Bulletin Number 32-87, dated February 7, 1966, (or later FAA approved revision), and each Model 22M Aircraft axle beam assembly P/N 1057-68-1 in accordance with General Dynamics/Convair 880M Service Bulletin Number 32-56, dated February 7, 1966, (or later FAA approved revision). (b) Removal of beam material extending below .006 inch depth from the original beam surface will require individual evaluation by the Chief, Aircraft Engineering Division, FAA Western Region. This amendment becomes effective October 18, 1969.
70-05-06: 70-05-06 HARTZELL PROPELLERS: Amdt. 39-954. Applies to Hartzell T10176( ) and T10176H( ) type blades installed on Hartzell HC-B3TN-5C series propellers used on AiResearch TPE331-( ) type engines. Compliance required as indicated, unless already accomplished. a. Propellers with 700 or more total hours in service, inspect in accordance with paragraphs (c) and (d) within the next 50 hours after the effective date of this AD, and reinspect in accordance with paragraph (c) every 1500 hours in service from the last inspection. b. Propellers with less than 700 total hours in service inspect in accordance with paragraphs (c) and (d) prior to the accumulation of 750 hours in service and reinspect in accordance with paragraph (c) every 1500 hours in service from the last inspection. c. Remove the blades from the propeller and the smaller needle bearing from the bottom of the blade pilot tube hole. In accordance with Hartzell Bulletin No. 95 dated 7 January 1970, or FAA approved equivalent procedure, clean and inspect the inner surface of the pilot tube hole for cracks by dye penetrant method and visually inspect for scratches, gouges or tool marks in the area of minimum wall thickness. Replace before further flight any cracked blade or blade having scratches, gouges, or tool marks in the critical radius with a blade which has been inspected in accordance with this AD and found satisfactory. d. Inspect the blade for minimum wall thickness in the shank area in accordance with Hartzell Bulletin No. 95 dated 7 January 1970. Replace before further flight any blade having a wall thickness less than that noted in Bulletin No. 95 with a blade inspected in accordance with this AD and found satisfactory. e. Upon submission of substantiating data through an FAA Maintenance Inspector, the Chief, Engineering and Manufacturing Branch, FAA Eastern Region may adjust repetitive inspection intervals specified in this AD. (Hartzell Bulletin No. 95 dated7 January 1970 and Manual 118A cover this subject.) This amendment is effective March 11, 1970.
67-30-02: 67-30-02 BRITISH AIRCRAFT: Amdt. 39-507, Part 39, Federal Register November 4, 1967. Applies to Model BAC 1-11 200 and 400 Series Airplanes which incorporate Modification PM 1558 part (c). Compliance required as indicated unless already accomplished. To prevent fatigue damage of the lower sidestay pin retaining bolt, P/N AC43-267, accomplish the following: (a) Within the next 200 landings after the effective date of this AD or before the accumulation of 5,000 landings, whichever occurs later, and thereafter at intervals not to exceed 5,000 landings from the last inspection, inspect the main landing gear lower sidestay retaining bolts, P/N AC43-267, for cracks, using the magnetic particle procedure or an FAA-approved equivalent, in accordance with British Aircraft Corporation BAC 1-11 Alert Service Bulletin 32- A-PM 2898, Issue 1, dated April 14, 1967, or later ARB-approved issue, or an FAA-approved equivalent. (b) If defective retaining bolts, P/N AC43-267, are found during the inspection required by paragraph (a), before further flight replace the bolts with serviceable bolts of the same part number or new bolts, P/N AC43-399, in accordance with BAC 1-11 Service Bulletin No. 32-PM 2898 Revision 1, dated April 10, 1967, or later ARB-approved issue, or an FAA- approved equivalent. (c) Before the accumulation of 15,000 landings, replace retaining bolts, P/N AC43- 267, with serviceable bolts of the same part number or new bolts, P/N AC43-399. If bolts P/N AC43-267 are used as replacement bolts, inspect the bolts at intervals not to exceed 5,000 landings in accordance with paragraph (a) and replace the bolts at intervals not to exceed 15,000 landings. (d) The repetitive inspections and replacements required by paragraphs (a) and (c) may be discontinued after the new bolts, P/N AC43-399, are installed. Retaining bolt P/N AC43- 399 does not have a service life limitation. (e) For the purpose of complying with this AD, subject to acceptance by the assigned FAA maintenance inspector, the number of landings may be determined by dividing each airplane's hours' time in service by the operator's fleet average time from takeoff to landing for the airplane type. This amendment effective December 4, 1967.
58-15-01: 58-15-01 DOUGLAS: Applies to DC-6 and DC-7 Series Aircraft. \n\n\tCompliance required by September 1, 1958. \n\n\tHook assemblies, P/N CSS1000-D, installed in safety belt assemblies, P/N 5610175, have been found to be understrength due to improper heat treat by the vendor. \n\n\tAll DC-6 and DC-7 Series aircraft equipped with these safety belt assemblies that were manufactured during the months of December 1957, January 1958, and February 1958, are affected. These belts can be identified by the manufacturing date (month and year) stamped on the part number tag sewn on the belt (i.e., date manufactured, December 1957, etc.). Belt assemblies manufactured prior to these dates are satisfactory and all future DC-6 and DC-7 aircraft will have safety belts with proper hook assemblies installed. \n\n\tAll hook assemblies that give a Rockwell reading of 36 or above on the "C" scale are satisfactory. Those that show a Rockwell reading below 36 are unsatisfactory and the belt must be replaced.(Douglas Alert Service Bulletin A-779 for the DC-6 Series and A-321 for the DC-7 Series cover the above subject and describe acceptable inspection and replacement procedures.)
69-11-02: 69-11-02 BELL: Amdt. 39-769. Applies to Bell Model 206A Helicopters, Serial Numbers 4 through 408, having the cyclic stick balance spring installed. Compliance required prior to the next flight after the effective date of this AD, unless already accomplished. To prevent a possible restriction of the cyclic control system, accomplish the following one time inspection and readjustment, if necessary: A. Remove the co-pilot's seat, P/N 206-031-141, to expose the cyclic control left pivot and yoke. B. Inspect and readjust, if necessary, the balance spring clip, P/N 206-001-391, for proper mounting on the yoke, left hand, P/N 206-001-322, in accordance with paragraph (C) below. C. The clip, P/N 206-001-391, must be mounted on the left hand outboard side of the clevis of the yoke, P/N 206-001-322, with the .38 by .16 inch tang of the clip against the top surface of the yoke pointing inboard. (Figure 1 in Bell Helicopter Company Service Letter No. 206A-104, Revision B, dated January 17, 1969, and Bell Helicopter Company information letter dated May 16, 1969, pertain to this subject). This amendment becomes effective to all known owners of Bell Model 206A Helicopters upon receipt of this AD and to all others on May 28, 1969.
52-07-01: 52-07-01 BELL: Applies to All Model 47D1 Helicopters Prior to Serial Number 477. Compliance required by May 15, 1952. To provide simplified loading limitations, remove the existing loading chart decal from the left side of the instrument panel and install loading limitation decal 47-796-109-1 at the same location. In addition, provide stowage space and install the fuel tank dip stick 47-686-205. (Bell Service Bulletin No. 86 covers this same subject.)
55-25-01: 55-25-01 BELL: Applies to Model 47G Helicopters Below Serial Number 1450 Which Have Hydraulic Boost System Installed. Compliance required as soon as practical but not later than January 15, 1956. The manufacturer advises that the lateral cyclic bellcrank, P/N 47-725-073-1 attachment bolt P/N AN 174-34 is too short, positioning the threaded area in the forward lateral bellcrank support bracket hole, which may result in the threads flattening out and elongating the support bracket bolt hole. It is therefore requested that the bolt holes in the bellcrank support bracket be inspected for elongation and the bolt replaced with a longer bolt. If the bolt holes are found elongated beyond permissible tolerance (maximum hole diameter of 0.2520 inch) doubler plates must be added. Redrill and line ream new holes. Replace the AN 174-34 bolt with a new longer bolt P/N AN 174-35, unless doubler plates are added, in which case install AN 174-36 bolts. (Bell's Mandatory Service Bulletin No. 104, dated November 11, 1955, covers this same subject.)
67-29-03: 67-29-03 FAIRCHILD-HILLER: Amdt. 39-499 Part 39 Federal Register October 25, 1967. Applies to all F-27J and FH-227 aircraft with installed Solar Auxiliary Power Unit Model T-62T-25, Serial Nos. S-408000 to S-408099 inclusive. Compliance required as indicated unless already accomplished, or unless APU is rendered electrically inoperative and APU controls are placarded to prohibit operation. To provide adequate APU fire detection system reliability and sensitivity, accomplish the following modifications: (a) Within the next 100 operational APU hours following the effective date of this AD, install an additional fire detector, Solar P/N 7447-2, (set at 400 25 degrees F) in accordance with Fairchild-Hiller Service Bulletin Nos. F-27-49-4 Revision 3, dated Sept. 25, 1967 or FH-227-49-4 Revision 3 dated Sept. 25, 1967 as applicable, or later FAA approved revision, or an equivalent modification approved by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region. (b) Within the next 100 operational APU hours following the effective date of this AD, install MIL-W-25038B fire resistant wire in the fire detection circuit in accordance with Fairchild-Hiller Service Bulletin Nos. F27-49-6 dated July 10, 1967 or FH227-49-6 dated July 10, 1967 as applicable, or later FAA-approved revision, or an equivalent modification approved by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region. (c) Within the next 200 operational APU hours following the effective date of this AD, replace the two existing 700 degree fire detectors, Solar P/N 7447-1 with two 400 + 25 degree F Fire detectors Solar P/N 7447-2. NOTE. - Compliance with paragraph (c) may be accomplished by arranging for the detector manufacturer, Fenwal, Inc. of 900 Main Street, Ashland, Massachusetts 01721, Solar P/N 7447-1 with two 400+25 degree F fire and reidentify the detector by P/N 7447-2. (d) Upon the effective date of this AD, APU operational hours will belogged until such time as the entire AD has been complied with. This amendment effective October 27, 1967.
53-12-02: 53-12-02 de HAVILLAND: Applies to Model DHC-2 (Beaver) Aircraft, Serial Numbers 1 to 451 Inclusive. Compliance required as indicated. Cases have been reported of loss of seals in the flap hydraulic hand pump No. 430RDH. To prevent the above condition a modification (No. 2/926) was incorporated on production aircraft and should be incorporated on aircraft in service as soon as possible but not later than the next 100 hours. The FAA concurs in this mandatory action by the Canadian Department of Transport. (de Havilland Technical News Sheet, Series B, No. 63 dated March 19, 1953, available from de Havilland Aircraft of Canada, Ltd., Toronto, Ontario, Canada, covers this same subject and describes method of repair.)
70-16-09: 70-16-09 AIRESEARCH: Amdt. 39-1064. Applies to Model TPE331-3W-301A engines, S/N P01001 through P-01010 and P-01012, P-01014, and P-01015, installed in but not limited to Handley-Page Model C10A aircraft. This directive necessary because of a serious condition which may be caused by backing off of the high speed pinion retaining nut. To prevent engine failures from this cause, the following is required: Replace the high speed pinion assembly P/N 869441-2 in accordance with AiResearch telegraphic service bulletin No. 622, dated July 24, 1970, or later FAA approved revision, prior to further use. This amendment is effective upon publication in the Federal Register for all persons except those to whom it was made effective immediately by telegram dated July 24, 1970.
47-10-19: 47-10-19 LOCKHEED: (Was Mandatory Note 21 of AD-763-3.) Applies to All Model 49 Serials Up to and Including 2088, Except as Noted. Compliance required not later than 100 hours of operation after June 10, 1947. (a) In each cabin heater installation, relocate and waterproof the fuel solenoid valve and replace and reroute the fuel pump bypass line. (LAC Service Bulletin 49/SB-73 covers this same subject.) (b) In zone 2 of each nacelle, install heat protective shield between propeller feathering line and cowl diaphragm. Applies to all serials up to and including 2082. (LAC Service Bulletin 49/SB-150 covers this same subject.) (c) In each outboard nacelle main junction box, replace existing mounting nuts (tinnerman) and PK screws with AN 366 nuts and NAS 221 screws. (LAC Service Bulletin 49/SB-152 covers this same subject.) (d) Drill one 1/4-inch drain hole on lower center line of spinner fairing lower panel assembly for each engine. (LAC Service Instruction 49/SI-95 covers this same subject.)
50-13-01: 50-13-01 CONVAIR: Applies to All Model 240 Aircraft. Compliance required as indicated. Failures of the wing portion of the aileron hinge brackets and bracket supports have been experienced on Convair Model 240 aircraft. These failures have been the result of excessive lateral vibration of the ailerons experienced mainly during engine operation between 1,000 to 1,200 r.p.m., in aircraft incorporating Hamilton Standard propellers. In order to preclude the possibility of these failures progressing to such a state that the airworthiness of the airplane is impaired, it is considered necessary that the following be accomplished on Convair Model 240 Series aircraft: A. To be accomplished on all individual CV-240 Series aircraft incorporating Hamilton Standard propellers at every No. 2 operation, until part B, is accomplished. Inspect the aileron in area of hinge brackets, aileron hinge brackets and bracket supports with a 10-power glass, for signs of fatigue cracking. Special attention should be paid to the areas around the rivet holes utilized for attaching the brackets to the bracket supports and to that portion of the bracket supports in the areas at which the bracket supports extend from the wing trailing edge structure. Any failed parts should be adequately repaired or replaced prior to the next flight. B. To be accomplished by January 1, 1951, on airplanes incorporating Hamilton Standard propellers. Incorporate steel aileron hinge brackets and incorporate measures to increase the lateral rigidity of the wing portion of the aileron hinges. (CVAC Service Bulletin 240-289 covers this same subject.)
65-13-06: 65-13-06 LOCKHEED: Amdt. 39-88 Part 39 Federal Register June 23, 1965. Applies to Models 1049C, 1049D, 1049E, 1049G, and 1049H Series aircraft. Compliance required as indicated. To detect cracked beam cap tie-in fittings, accomplish the following: (a) Inspect the beam cap tie-in fittings, Lockheed P/N's 311134L and 311134R, on the upper forward face of the rear spar at Wing Stations 80L and 80R for cracks in the area of the 0.16 inch radius near the center of the fitting, using dye penetrant or an FAA-approved equivalent as specified in (b) or (c) as applicable. (b) Inspect fittings with 20,000 or more hours' time in service on the effective date of this AD in accordance with (a) within the next 350 hours' time in service unless already accomplished within the last 3,150 hours' time in service, and at intervals thereafter not to exceed 3,500 hours' time in service from the last inspection. (c) Inspect fittings with less than 20,000 hours' time in service on the effective date of this AD in accordance with (a) within 350 hours' time in service after the effective date of this AD unless already accomplished, and - (1) If the fittings had 16,850 or more hours' time in service at the time of the inspection, reinspect at intervals not to exceed 3,500 hours' time in service from the last inspection; (2) If the fittings has less than 16,850 hours' time in service at the time of the inspection, reinspect before the accumulation of 20,350 hours' time in service and at intervals thereafter not to exceed 3,500 hours' time in service from the last inspection. (d) Replace any fitting found cracked with a new fitting of the same part number before further flight. (e) Operators who have not kept records of hours' time in service on individual fittings shall substitute airplane hours' time in service in lieu thereof. (f) Upon request of the operator, an FAA maintenance inspector, subject to prior approval of the Chief, Aircraft Engineering Division, FAA Western Region, may adjust the repetitive inspection intervals specified in this AD to permit compliance at an established inspection period of the operator if the request contains substantiating data to justify the increase for such operator. This supersedes AD 64-06-05. This directive effective July 23, 1965.
94-01-12: This amendment supersedes an existing airworthiness directive (AD), applicable to all Airbus Industrie Model A310-200 and A310-300 series airplanes series airplanes, that currently requires inspections and tests to detect broken or missing vespel bushes in the flap universal joint assemblies, and replacement of universal joint bushes, if necessary. This amendment adds a terminating modification for the currently required inspections and tests. This amendment is prompted by the development of a modification that will improve the integrity of the flap universal joints. The actions specified by this AD are intended to prevent rupture of the flap universal joints, subsequent partial loss of lift in one wing, and reduced controllability of the airplane.
90-08-07: 90-08-07 BRITISH AEROSPACE: Amendment 39-6600. Docket No. 90-NM-60-AD. Final copy of Priority Letter AD. Applicability: Model BH.125-600A, HS.125-700A, and BAe 125-800A series airplanes, equipped with a cabin interior and aft lavatory water system installed in accordance with STC SA2271SW, certificated in any category. Compliance: Required prior to further flight, unless previously accomplished. To prevent loss of aileron control, accomplish the following: A. Drain all water from the aft lavatory water system reservoir, deactivate the water system pressure pump by pulling the circuit breaker located beneath the vanity in the aft lavatory, and install a tie wrap on the circuit breaker to prevent it from being reset. B. 1. The aft lavatory water system pressure pump may be reactivated upon accomplishment of a modification which has been approved by the Manager, Special Programs Office, ASW-190, FAA, Southwest Region. 2. An alternate means of compliance or adjustment of the compliance time, which provides an acceptable level of safety, may be used when approved by the Manager, Special Programs Office, ASW-190, FAA, Southwest Region. NOTE: The request should be forwarded through an FAA Principal Maintenance Inspector (PMI), who will either concur or comment and then send it to the Manager, Special Programs Office, ASW-190. C. Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base in order to comply with the requirements of this AD. This amendment (39-6600, AD 90-08-07) becomes effective on May 29, 1990, as to all persons, except those persons to whom it was made immediately effective by priority letter AD 90-08-07, issued April 10, 1990, which contained this amendment.