SERVICE KIT Thru A Thru

Transcription

1 TITLE WING FRONT SPAR LOWER CAP MODIFICATION EFFECTIVITY MODEL(S) SERIAL NUMBERS Thru A Thru * Order these items only if replacement is necessary. DESCRIPTION The following procedures provide instructions to install external doublers and straps on lower surface of the wing front spar. APPROVAL FAA approval has been obtained on technical data in this publication that affects airplane type design. REFERENCE MEB92-XX Multi-Engine February 8, 1980 Revision B - January 27, 1995 Page 1 of 12 To obtain satisfactory results, procedures specified in this publication must be accomplished in accordance with accepted methods and prevailing government regulations. The Cessna Aircraft Company cannot be responsible for the quality of work performed in accomplishing the requirements of this publication. The Cessna Aircraft Company, Product Support, P.O. Box 7706, Wichita, Kansas 67277, U.S.A. (316) , Facsimile (316) COPYRIGHT 1995 In addition to the parts furnished in this kit the following sealants will be required to complete this modification: PART NUMBER QUANTITY DESCRIPTION MIL-S-8802IIB2 2 Sealant (Semkit, 6oz) CMNP009 (or equivalent) 2 Firewall Sealant (alternate is ProSeal 700) Airplane Models 411 A, serials thru order the following parts: PART NUMBER QUANTITY DESCRIPTION Refrasil Cloth 1 20 x 30 (F780222) NAS1399M Rivet NAS1738M Rivet NAS1739M Rivet NAS1739M Rivet * Doubler - LH * Doubler - RH

2 CHANGE IN WEIGHT AND BALANCE MODEL /411A WEIGHT INCREASE Pounds ARM Inches RESULTANT MOMENT Inch-Pounds MOMENT/ MATERIAL INFORMATION Page 2 PART NUMBER QUANTITY DESCRIPTION 1 Kit, Consisting of the following parts: HL18PB Hi-Lok Pin HL19PB Hi-Lok Pin HL19PB5-4 2 Hi-Lok Pin HL19PB Hi-Lok Pin HL19PB Hi-Lok Pin HL19PB Hi-Lok Pin HL Hi-Lok Collar HL Hi-Lok Collar MS20426A6-6 2 Rivet NAS1097AD Rivet NAS1738B Rivet NAS1739B4-4 6 Rivet NAS1739B4-6 8 Rivet NAS1739B Rivet NAS1739B Rivet NAS1739B4-9 4 Rivet NAS1739M4-3 3 Rivet Drawing, Sheet 1 & Doubler-Inboard Insulation Channel, RH Channel, LH Channel, RH Angle, LH Angle, RH Angle, LH Angle, RH Shield Doubler, Center Doubler, Outboard Strap 1 Installation Instructions

3 ACCOMPLISHMENT INSTRUCTIONS This Service Kit modifies the lower front spar by installing a doubler and strap on the lower front spar cap horizontal flange, extending from the wing root fitting, outboard to just past the engine beams. These instructions do not include complete step by step procedures and must be used in conjunction with Cessna Modification Drawing included with this kit during the performance of this modification. Due to varying length requirements, all driven type rivets have been omitted from this kit. The modification drawing should be referenced for rivet diameters and each hole should be individually checked for length requirements. All Refer to Zone references used in the instructions of this Service Kit are the zone locations noted on the modification drawing. Step 8 of these procedures provide information regarding the fastener codes used on the modification drawing and to assist in determining the proper hole size requirements. These instructions are divided into the eight (8) following sections: 1. Preparation 2. Component Removal 3. Lower Front Wing Spar Cap Modification, LH and RH 4. Eddy Current Inspection of Lower Spar Cap and Spar Cap Vertical Flange 5. Lower Front Spar Strap and Doublers Installation 6. Doubler (Steel) and Insulation Installation (Model 411A, Serial numbers thru Only) 7. Components Reinstallation 8. Fastener, Symbols and Codes 1. Preparation. A. Defuel the airplane of all fuel from the main wing, tip tanks and wing auxiliary tanks in accordance with procedures outlined in the Service Manual. B. Place airplane on jacks in accordance with the Service Manual procedures. Remove the wing gap panels around the wing root area of the LH and RH wings. Retain all hardware for reinstallation. C. Place a jack under the forward wing attach fitting (using wood blocks to prevent damage), LH and RH wings. Raise the airplane enough so that the jacks are supporting the fuselage weight. D. Place a tail stand under the tail section of the airplane. E. Place a jack outboard of Wing Station under the lower, front, spar cap (using wood blocks to prevent damage) to support the outer most weight of the wings. Supporting of the LH and RH wings during this modification is very important. The wings must be supported in a relaxed state (removal of all fuselage weight). There will be a large amount of rivets removed in a major portion of the lower front spar cap. Each wing must be secure and not moved during the modification so that the rivet holes through the lower spar cap will not shift and cause wing twist. 2. Component Removal A. Remove all engine cowlings from LH and RH engine, refer to the Service Manual for removal instructions. Page 3

4 The following procedures apply to the LH portion of the modification. The RH portion of the modification is the same except for part number differences. B. Disconnect and lower the inboard landing gear door. Refer to the Service Manual for procedures, retain all hardware. C. Disconnect and remove the outboard drive tube assembly that is connected between the idler bellcrank and torque tube assembly. Refer to the Service Manual for removal procedures. Retain all hardware for reinstallation. D. Remove all access panels and covers in the modification area. Retain all parts for reinstallation. E. Remove rivets attaching the following: Lower Center Skin Assembly, Forward Inboard Lower Skin, Forward Outboard Lower Skin and Inboard Fairing. It may not be necessary to remove every rivet in the skins. Some of these skins only need to be partially removed to allow access to the modification area. WARNING: WORKING WITH ASBESTOS OR MATERIALS CONTAINING ASBES- TOS FIBERS MAY BE HAZARDOUS TO YOUR RESPIRATORY SYS- TEM. WEAR A PROTECTIVE INHALATION DEVICE FOR PROTEC- TION WHEN WORKING WITH ASBESTOS MATERIALS. F. (Model 411A, Serial numbers thru only.) Remove the Doubler (steel) and insulation (asbestos) by drilling out the attaching rivets. Discard the insulation properly in conjuction with EPA guidelines and examine the doubler for damage. If the doubler is damaged, order a new one per information in the parts list for later reinstallation. When drilling out rivets to remove skin panels, ensure the holes do not become elongated or distorted. 3. Wing Front Spar Lower Cap Modification, LH and RH. A. (Refer to Zone 18A, View J-J and Zone 20A, View H-H.) Mark a trim line, per dimensions shown, on the Angles, two places; inboard side of inboard engine beam and the outboard side of outboard engine beam. Remove rivets as required to remove the angles. Cut on the trim line and discard the forward portion of the angles. Deburr the edge and polish smooth using 400 grit sandpaper. Retain the angles for later reinstallation. B. (Refer to Zone 16A, Detail E.) Layout and mark the cutout through the Channel and engine beam as shown, inboard and outboard engine beams. Carefully cutout the area on each engine beam and Channel using a pin router and small diameter rotary file to provide for passage of the Strap through the engine beams. Deburr the cutout edges and polish smooth using 400 grit sandpaper. CAUTION: DO NOT CUT INTO OR THROUGH THE UPPER FLANGE OF EITHER THE ENGINE BEAM OR THE CHANNEL. C. (Refer to Zone 16B, View F-F.) Layout and mark the cutout in the Stiffener as shown. Slide a thin piece of steel between the Stiffener and the wing skin to prevent damage to the wing skin during the cutting operation. Carefully cut out the area using a pin router and small diameter rotary file to provide passage of the Strap. Deburr the edges and polish smooth using 400 grit sandpaper. D. (Refer to Zones 1 thru 8.) Place the , and Doublers in position on the lower wing skin as shown. Mark around the perimeter of the doubler on the wing skin using a felt tip pen. Remove the doublers and remove all rivets within the areas marked that will attach the doublers to the wing. When removing rivets, drill off the heads of the rivets using the proper size drill bit. Drive the shank on through the spar using a pin punch of the correct size. Page 4

5 E. Place the , and Doublers one at a time over the holes drilled out in the lower front spar cap. Using an undersize drill bit and hole finder, locate holes in the doublers to match holes in the spar. Layout new rivet holes per dimensions shown and drill holes through the doublers and wing skin per step 8, for rivets called out on the Drawing. When drilling holes in the , and Doublers to match holes in the lower front spar cap, allow the drill to follow the existing alignment of the holes in the spar, so as not to elongate the existing holes in the spar. This is important as some of the holes may not be drilled perpendicular to the spar cap. F. Remove the , and Doublers and ensuring careful alignment, transfer the holes to the Strap using an undersize drill bit. G. Place the Strap, , and Doublers back onto the lower front spar cap. Secure with temporary sheet metal fasteners. H. Enlarge holes through the lower Strap and , , Doublers to the correct diameter. Refer to Drawing and the hole size table in step 8 at the conclusion of these procedures to determine the proper hole diameters. Use temporary sheet metal fasteners to hold the parts in position. Holes requiring installation ofhl18pb and HL19PB Hi-Lok Fasteners must be drilled and reamed to the dimensions specified in the hole size table of these procedures. Where possible, it is desirable to obtain the low side of the tolerance which will achieve a slight interference fit. An interference fit will prevent the fasteners from rotating and will eliminate the requirement of holding the fastener with a hex wrench when collars are installed. I. (Refer to Zone 19A and 20A.) Place the modified Angle back in position on the inboard engine beam as shown and fasten in place using temporary sheet metal fasteners. Place the Channel (use Channel for the RH wing) in position as shown and drill holes through the channel into the lower front spar cap and wing skin as required to match existing holes. Use temporary sheet metal fasteners to hole the channel in position. Do not drill through the vertical portion of the engine beam at this time. Place the Angle (use Angle for the RH wing) in position and drill two (2) holes through the angle to match holes in the lower front spar cap. Drill holes through the Angle to match existing holes in the vertical portion of the engine beam. Layout and mark new rivet holes as shown and drill through the angle, engine beam and the Channel. Use temporary sheet metal fasteners to hold all parts together as the drilling progresses. Use step 8 in these instructions and Drawing to determine proper hole size. J. (Refer to Zone 17A and 18A.) Repeat Step 12 for the outboard engine beam using a Channel (use for the RH wing) and a Angle (use Angle for the RH wing). K. (Refer to Zone 6C.) Place the Insulation and the Shield in position and drill through the insulation and shield as required to match holes in the Strap. Use temporary sheet metal fasteners to hold the shield and insulation in place. L. Remove all parts and deburr all holes. Page 5

6 4. Eddy Current Inspection of Lower Spar Cap. An eddy current inspection in accordance with the following procedures must be performed on all holes in the lower forward spar cap horizontal flange after the Straps have been fitted. Only those holes in the spar cap and vertical flange common to the Straps will require inspection. Cracks detected during this inspection must be reported to Cessna Product Support along with the following information: Hole diameter, Location of hole, Hole edge distance, Length and direction of crack. A. Equipment Required. (1) Crack Detector - Eddy Current Unit Model ED-520 (Magnaflux Corp.) or equivalent. (2) Bolt Hole Probe - 5/32 diameter - 1 1/2 maximum length with split stem and collar. (VM101BS-5/32) (3) Bolt Hole Probe - 3/16 diameter - 1 1/2 maximum length with split stem and collar. (VM101BS-3/16) (4) Bolt Hole Probe - 1/4 diameter - 1 1/2 maximum length with split stem and collar. (VM101BS-1/4) (5) Calibration Block - Manufactured per Figure 1. or calibration block is available from Cessna Supply Division. Suggested source for items 2, 3 and 4 - VM Products, P.O. Box 44926, Tacoma, Washington (Specify cable connector when ordering if other than B.N.C.) B. Inspection. (1) Prior to the inspection and after removal of rivets check the wing skin and web for any excessive gap between skin and spar. To eliminate any gap use temporary fasteners to hold skin in contact with the spar during inspection. (2) Clean fastener holes using solvent with a nonmetallic brush or cotton swab to remove grease, dirt, metallic chips, etc. (3) Adjust probe depth to 0.07 inch from collar to center of coil. Standardize the eddy current instrument for balance and lift-off in accordance with the manufacturer s operator handbook, using calibration block with probe inserted from notched surface, and with coil away from notched side of hole. Make final lift-off adjustment by pushing coil away from side of fastener hole. Meter should read the same when coil is in contact or away from side of hole. Adjust sensitivity to induce 100 ± 10 micro amperes deflection when coil is rotated past notch. (Down scale deflection on Model ED520.) (4) Probe depth settings: (a) Spar cap fastener holes inches. (b) Spar vertical flange inches. (5) Scan each fastener hole with a full 360 scan. Rotate probe slowly while observing the meter readings. Pay particular attention to the critical areas of the holes. Critical area for spar cap holes is in the forward and aft direction. The vertical flange is in the vertical direction (up and down). If probe passes over a crack, the meter needle will deflect rapidly and return to approximately the original reading. Carefully repeat the inspection in the opposite direction to verify the crack indication. Gradual meter needle movement up or down scale may occur due to slightly out of round holes or minor changes in the conductivity of the material. This should be disregarded. Page 6

7 5. Front Spar Lower Strap and Doublers Installation. A. Place the , , Doublers and the Strap in position on the lower front spar cap. Also place the Insulation and the Shield in position on the strap. Use temporary sheet metal fasteners to hold the parts in position. B. (Refer to Zone 17A, 18A, 19A and 20A.) Place the Angle, Angle, Channel, Channel and both existing Angles in position on the inboard and outboard engine beams. Secure these parts in position using fasteners as shown. C. Secure the , , Doublers and the Strap in position using fasteners as shown. 6. Steel Doubler and Insulation Installation (Models 411A, Serial numbers thru only). A. (Refer to Zone 6B.) Trim the forward edge of the existing (or new if required) Doubler (steel) as shown to clear the Strap. Deburr the edge and polish smooth with 400 grit sandpaper. B. Place the Doubler in position and using a hole finder, drill (.128) and (.143) diameter holes as required to match existing holes. Use temporary sheet metal fasteners to hold the doubler in position as the drilling progresses. WARNING: WORKING WITH ASBESTOS OR MATERIALS CONTAINING ASBESTOS FIBERS MAY BE HAZARDOUS TO YOUR RESPIRATORY SYSTEM. WEAR A PROTECTIVE INHALATION DEVICE FOR PROTECTION WHEN WORK- ING WITH ASBESTOS MATERIALS. C. Remove the doubler and deburr all the holes. Cut a piece of F refrasil cloth to fit on the upper surface of the doubler. D. Secure the Doubler and F refrasil cloth in position using NAS1399M4-2, NAS1738M4 and NAS1739M4 Rivets. 7. Components Reinstallation. A. Repeat Sections and 6. for the RH wing. B. Reinstall the lower nacelle skins to the wing. Retrim skins as required to clear the Strap. Use the table on Drawing, Zone 8D. C. Connect the outboard drive tube assembly to the idler bellcrank and torque tube assembly. Refer to the Service Manual for installation procedures. D. Perform a landing gear rigging check in accordance with the Service Manual. E. Reconnect the lower, inboard landing gear door. F. Remove tail stand from under airplane tail section. G. Remove jack blocks from the forward attach fittings and from outboard of the engine nacelle. Reinstall wing gap fairing on the LH and RH wing. H. Paint the lower front spar cap as required to match the color of the airplane in accordance with the Service Manual. I. Make an entry in the airplane logbook stating this kit has been installed. 8. Fastener Symbols and Codes. A. The symbol includes a single cross whose intersection is at the location of the fastener. When space does not permit, the symbol may be located adjacent to the area. (1) Fastener identity, size, installation requirements, etc., shall be indicated by a letter-numeric coding within the quadrants of the symbol (cross). Page 7

8 (2) Quadrant Orientation of the symbol is determined by the direction of the letter-numeric coding as written within the symbol. When the symbol is viewed in a position such that the letters are upright, the upper left quadrant is NW, etc. The following examples illustrate the basic symbol and quadrant identity. (a) Northwest (NW) Quadrant. 1 The identity of the fastener is shown in the NW quadrant by a letter code. The code is made up of insignificant letters and defines all features of the fasteners except diameter and grip. An example of the symbol and fastener code (b) Northeast (NE) Quadrant. 1 Fastener diameter and location of the manufactured head is shown in the NE Quadrant by a numeric letter code. The fastener diameter is shown by a number which is the dash number that represents the diameter in the full part number. If the diameter is designated by digits of the basic part number, then the significant digits shall be shown. The location of the manufactured head of the fastener is defined by the code letter F for far-side and N for near-side. When the location of the manufactured head is insignificant, the code letter may be omitted. An example of the symbol, fastener diameter and location of manufactured head (c) Southeast (SE) Quadrant. 1 The length and permission to spot weld as an alternate assembly method is shown in the SE quadrant by a numeric-letter code. 2 The length is shown by a number which is the dash number that represents the length in the full part number. 3 Engineering permission to spot weld in lieu of using the fastener called for its denoted by the letter W. 4 The preceding data is an optional feature of the code, but the use of any alternate method of designating the preceding data within the symbol is not optional. An example of the symbol, fastener length and spot weld alternate (d) Southwest (SW) Quadrant. 1 Dimple and countersink data - The sheets to be dimpled or countersunk are shown in the SW quadrant by a numeric-letter code as defined below, not to exceed three digits per line. Unless otherwise noted, the normal angle for the dimple or countersink shall be the same as the angle of the manufactured rivet head. a The letter D is used to show dimpling (form of countersinking) operation and when more than one sheet is dimpled a number follows the D to show how many sheets are dimpled. Page 8 BJ 4F 4N W 5W 5 NE NW SE SW

9 b The letter C is used to show countersinking operation. No number is used after the countersinking designation because it is the responsibility of the individual to see that the thickness of material to be countersunk for a flush condition will not violate structural requirements. Example: c Protruding head rivets to be upset flush may be indicated by placing the numeric letter code on the first line which indicates the dimple or countersink operation for the upset end. The second line indicates the nominal angle for the upset end. Example: d The flush both sides condition may be indicated by placing the numericletter code on separate lines where: First line - The first line indicates the dimple or countersunk operation for the manufactured head. Second line - The second line indicates the dimple or countersink operation for the upset end. Third line - The third line indicates the nominal angle for the upset end when different than the angle of the manufactured head. Examples: Optional - Optional when the dimple-countersink operation for the double flush rivets are controlled by applicable company requirements, the instruction to double flush may be indicated by noting the angle of the manufactured head on the first line and the angle of the upset end on the second line. Examples: 2 The use of the dimple-countersink feature of the symbol is optional. Any alternate method of designating the dimple-countersink feature for the flush one or both sides within the symbol is not optional. B. Examples. (1) Description of Typical Symbols. (a) MS20470AD4 Rivet, Universal Head (head direction is not shown - assumed to be insignificant. Page 9 D3C C D2 DC C 100 C 82 C DC D2C C DC DC D2C C BJ

10 (b) MS20426AD4 Rivet, 100 Countersunk Head (head location not shown - assumed to be obvious in this case; since there is always a reason for using countersunk rivets, the head location of this type can never be insignificant). (c) MS20426AD4 Rivet, 100 Countersunk Head (manufactured head to be located on the near side). (d) MS20426AD4 Rivet, 100 Countersunk Head. First and second sheets adjacent to manufactured head to be dimpled, remainder of sheets to be countersunk. The location of the manufactured head is assumed to be obvious from the illustration in this case. (e) NAS1468 Lockbolt - Protruding Head, Close Tolerance Shank, including NAS1080 collar. The location of the manufactured head is assumed to be insignificant or obvious in this case. 1 For Flush Upset End on Protruding Head Rivet. 1st Line - Dimple or Countersink 2nd Line - Nominal Upset Angle 2 Flush Both Sides. 1st Line - Manufactured Head Dimple or Countersink 2nd Line - Upset Head Dimple or Countersink 3rd Line - Upset Head Angle, Different Manufactured Head 3 Flush Both Sides Optional. 1st Line - Nominal Angle of Manufactured Head 2nd Line - Nominal Angle of Upset Head Page 10 4 BB 4N BB 5 8 DT Basic Code Dash Number for Diameter (1/32 s) N = Manufactured Head Near Side F = Manufactured Head Far Side D = Dimple Figure = Number of Sheets to be Dimpled C = Countersunk (For Special Flush Conditions Only, See Notes a, b and c) Dash Number for Length W = Spotweld Optional D2C 4 BB

11 Rivet symbols are used on the drawing only at the beginning and ending of each series of rivets. This signifies that those specified in the beginning and ending symbols. * Standard hole sizes for these fasteners are #40 drill for size 3/32 inch diameter rivets, #30 drill for size 4/32 (1/8) inch diameter rivets and #21 size 5/32 inch diameter rivets. Page 11 RIVET CODE PART NUMBER HOLE SIZE BJ MS20470AD * STANDARD BB MS20426AD * STANDARD AAO/AAT NAS1738B4/NAS1739B (#27 DRILL) NAS1738B5/NAS1739B (#16 DRILL) NAS1738B6/NAS1739B (# 5 DRILL) WY HL19PB HL19PB (#12 REAMER) LZ NAS1097AD * STANDARD LN MS20615M * STANDARD AAR/AAW NAS1738M4/NAS1739M (#27 DRILL) YA HL18PB

12 Page 12 Figure 1. Eddy Current Calibration Block CALIBRATION BLOCK (REFERENCE) (ALSO AVAILABLE FROM CESSNA PART NUMBER , SEE BELOW) PROBE DEPTH SETTING FOR CALIBRATION VIEW A-A (TYPICAL) WHEN CESSNA MANUFACTURED CALIBRATION BLOCK IS USED ( ) ONLY THESE THREE (3) HOLES ARE REQUIRED FOR THIS INSPECTION CALIBRATION BLOCK (REFERENCE) 3.00 HOLES EQUAL SPACED ± DIAMETER DIAMETER DIAMETER 0.05 ± A A 1. MATERIAL 7075-T6 ALUMINUM ALLOY OR SIMILAR 2. ALL DIMENSIONS ARE INCHES 3. DRILL AND REAM HOLES TO SIZE,±0.005 TOLERANCE 4. WHERE HOLES REQUIRING INSPECTION HAVE BEEN DRILLED OVERSIZE, MANUFACTURE CALIBRATION BLOCK WITH APPROPRIATE HOLE DIAMETER NOTES: THIS SURFACE CUT NOTCHES WITH E.D.M. (ELECTRONIC DISCHARGE MACHINING)