1T-38-849.pdf

DEPARTMENT OF THE AIR FORCE

TECHNICAL ORDER

DISCLOSURE NOTICE - This information is furnished upon the condition that it will not be released to another nation without the specific authority of the Department of the Air Force of the United States, that it will be used for military purposes only, that individual or corporate rights originating in the information, whether patented or not, will be respected, that the recipient will report promptly to the United States, any known or suspected compromise, and that the information will be provided substantially the same degree of security afforded it by the Department of Defense of the United States. Also, regardless of any other markings on the document, it will not be downgraded or declassified without written approval of the originating United States agency.

DISTRIBUTION STATEMENT E - Distribution authorized to the DoD components only, Direct Military Support, 27 September 2010.

Other requests shall be referred to OO-ALC/GHMEH, HILL AFB, Utah 84056-5811.

WARNING - This document contains technical data whose export is restricted by the Arms Export Control Act (Title 22, U.S.C., Sec 2751 et seq) or the Export Administration Act of 1979, as amended (Title 50, U.S.C., App 2401 et seq). Violations of these export laws are subject to severe penalties. Disseminate in accordance with provisions of DoD Directive 5230.25.

DESTRUCTION NOTICE - Comply with distribution statement and destroy by any method that will prevent disclosure of the contents or reconstruction of the document.

TO 1T-38-849

DATA CODE 0113419

27 September 2010

NON-DESTRUCTIVE INSPECTION (NDI) OF

UPPER CENTER LONGERON SPLICE

AT FUSELAGE STATION (FS) 284.0 ON

T-38 AIRCRAFT

NOTE

Commanders are responsible for bringing this technical order to the attention of all

Air Force personnel cleared for operation of the affected system.

1. APPLICATION.

1.1 Identification. This Time Compliance Technical Order (TCTO) is applicable to the following T-38 aircraft:

6300008184 6300008192 6400013171 6400013172 6400013183 6400013193 6400013206 6400013217

6400013222 6400013224 6400013225 6400013239 6400013240 6400013247 6400013265 6400013266

6400013268 6400013270 6400013272 6400013280 6400013283 6400013285 6400013301 6400013304

6500010324 6500010336 6500010337 6500010342 6500010359 6500010361 6500010377 6500010379

6500010394 6500010418 6500010419 6500010421 6500010429 6500010438 6500010442 6500010445

6600004332 6600004346 6600004351 6600004366 6600004367 6600004372 6600004374 6600004375

6600004384 6600008352 6600008356 6600008369 6600008372 6600008373 6600008374 6600008375

6600008379 6600008389 6600008390 6600008391 6600008392 6600008393 6600008402 6700014826

6700014831 6700014844 6700014845 6700014846 6700014848 6700014851 6700014858 6700014919

6700014920 6700014926 6700014928 6700014937 6700014950 6700014955 6800008102 6800008110

6800008128 6800008134 6800008136 6800008142 6800008143 6800008147 6800008155 6800008179

6800008185 6800008189 6800008193 6800008203 6800008213 6900007074 6900007077 6900007080

6900007085 7000001559 7000001574 7000001578 7000001589 7000001950 7000001955

1.2 Kit Applicability. Kits are not required by this TCTO.

1.3 Proofing. TCTO verification was accomplished In Accordance With (IAW) TO 00-5-15, at Ellington Field, Texas (NASA) on aircraft Serial Number 67-14920 on 17 August 2010 and at Randolph AFB, Texas on aircraft

Serial Number 66-8358 on 29 July 2010.

2. PURPOSE.

The purpose of this technical order is to inspect the FS 284.0 aft splice fitting located on the upper center longeron.

The Aircraft Structural Integrity Program (ASIP) Office has determined these aircraft to be at increased risk for cracking.

3. WHEN TO BE ACCOMPLISHED.

Not later than 349 days after the receipt of this TCTO. Failure to accomplish this TCTO by the preceding specified number of days shall be justification for withdrawing affected system from service until compliance is accomplished.

If the compliance period cannot be met before the TCTO rescission date, the performing organization will be request an extended compliance period IAW TO 00-5-15.

3.1 TCTO Rescission Date. The TCTO Rescission date for this technical order is 26 September 2013, unless extended via TCTO supplement or notices received through the Reliability and Maintainability Information

System (REMIS) or other management information systems. This TCTO will be retained until listed as rescinded in the applicable index.

3.2 Remove From Service. The Remove from Service date is the expiration of the TCTO compliance period

OR 60 days prior to the rescission date, whichever comes first.

4. BY WHOM TO BE ACCOMPLISHED.

Organizational/Intermediate Level Maintenance or Contractor Equivalent.

5. WHAT IS REQUIRED.

5.1 Supply Information and Requirements.

5.1.1 Kits/Parts/Materials Required. The following parts, materials and tooling will not be furnished in a kit and shall be obtained from the appropriate supply source. The complete kit concept is waived by John Michalski (Chief, Primary Trainer Aircraft Section), HQ AETC/A4MAT, DSN 487-3171.

AF activities shall ensure TCTO kits/parts are requisitioned in an expeditious manner to ensure accomplishment of this TCTO within the designated time period.

Item quantity was estimated for removal/replacement for one aircraft.

Qty Stock Number Part Number Nomenclature Source

2* 5320-00-969-4523 HL19PB-6-11 Pin Rivet, CSK Hi-Lok AF Supply

2* 5320-00-969-4522 HL19PB-6-12 Pin Rivet, CSK Hi-Lok AF Supply

14* 5320-00-999-9407 HL19PB-6-4 Pin Rivet, CSK Hi-Lok AF Supply

14 5320-00-969-4521 HL19PB-6-5 Pin Rivet, CSK Hi-Lok AF Supply

14 5320-00-969-4520 HL19PB-6-6 Pin Rivet, CSK Hi-Lok AF Supply

4* 5320-00-959-0461 HL18PB-6-5 Pin Rivet, Protruding Head Hi-Lok AF Supply

15 5320-00-959-0463 HL18PB-6-6 Pin Rivet, Protruding Head Hi-Lok AF Supply

15 5320-00-969-4517 HL18PB-6-7 Pin Rivet, Protruding Head Hi-Lok AF Supply

15 5320-00-959-0475 HL18PB-6-8 Pin Rivet, Protruding Head Hi-Lok AF Supply

15* 5320-00-959-0480 HL18PB-6-9 Pin Rivet, Protruding Head Hi-Lok AF-Supply

58 5320-00-959-0134 HL 82-6 Collar, Self-Aligning Hi-Lok AF Supply

58 5310-00-176-6778 HL 82-6PBW Washer, Self-Aligning AF Supply

2 5306-01-258-7542 84492-10-24 Bolt, Attach FS 284 AF Supply

2-6** 5310-00-275-9211 MS200002C10 Washer, Beveled AF Supply

2 5310-01-259-3592 NAS 577B10A Nut, Barrel AF Supply

2 5340-00-064-6088 NAS 578-10B Retainer, Barrel Nut AF Supply

*Grip length of fastener to be determined to account for aircraft splice thickness differences.

**One beveled washer minimum under bolt head, but 1-2 additional washers may be used per bolt to prevent threaded end of bolt contacting FS 284.0 aft longeron splice fitting barrel nut recess.

5.1.2 Action Required on Items in Chief of Supply or Units Stock. Not applicable.

5.1.3 Kits/Parts/Materials Required to Modify Items in Stock. Not applicable.

5.1.4 Disposition of Removed and Replaced Parts/Materials.

Parts removed, but not listed, shall be processed to the local Defense Reutilization and Marketing Office if unserviceable or not cataloged. Serviceable stock listed items shall not be returned to stock unless the quantity removed exceeds $25.00 line item value.

5.1.5 Drawings and Instructions Required. Not applicable.

5.1.6 Size, Weight and Cost of Kits/Parts/Materials. Not applicable.

5.1.7 Disposition of Kits/Parts/Materials. Not applicable.

5.2 Personnel Information and Requirements.

WORK PHASES AFSC SKILLS MAN-HOURS

Unpacking N/A 0.0

Disassembly

2A3X3 or equivalent

2A7X3 or equivalent

136.0

Installation 2A752 or NAS-410 Level II 31.0

Assembly 2A7X3 or equivalent

2A3X3 or equivalent

43.0

Operational check 2A3X3 10.0

Total Man-Hours 220.0

5.3 Special Tools, Fixtures, Test Equipment and Software Required.

Stock Number Part Number Nomenclature Source

NSL NEC-8219

Kit, Probe, Bolt Hole, 1 1/16-inch, SUB-68R-4FX

-and-

Reference Standard, 1 1/16-inch

Olympus / NDT

Engineering

6. HOW WORK IS ACCOMPLISHED.

Personnel are advised to read and thoroughly familiarize themselves with the information contained in this TCTO. Minor deviations are authorized providing the intent of this TCTO is accomplished and safety is not compromised.

a. Make aircraft safe for maintenance IAW TO 1T-38A/C-2-1, and TO 1T-38A/C-2-2.

6.1 Disassembly.

a. Defuel and purge aircraft IAW TO 1T-38A/C-2-5 and TO 1-1-3.

b. Remove all sources of electrical power and aircraft battery IAW TO 1T-38A/C-2-7.

wWa

A Confined Space Permit will be initiated prior to any work being accomplished in the forward fuselage fuel cell, and for the duration of all activities in the forward fuselage fuel cell, until the forward fuselage fuel cell reinstallation is complete IAW

MIL-STD-38784D and AFOSH 91-25. Failure to comply with Confined Space

Guidelines may result in illness, injury or death to personnel.

c. Remove forward fuselage fuel cell IAW TO 1T-38A/C-2-5.

All stress panels will be installed prior to any jacking, down-jacking and/or towing operation or damage to aircraft may result.

d. Jack and level aircraft using wing and nose jacks IAW TO 1T-38A/C-2-1.

e. Install two aft fuselage jacks IAW TO 1T-38A/C-2-1 until snug.

f. Remove access door numbers 185 and 186 or 171 and 174 (door number depends on aircraft serial number)

IAW TO 1T-38A/C-2-2.

g. Remove left and right electrical equipment racks to access bolts at FS 284.0 IAW TO 1T-38A/C-2-7.

Only non-metallic scrapers and/or sealant removal tools will be used to remove sealant in the forward fuselage fuel cell or damage to the FS 284.0 longeron splice area may result.

h. Remove sealant and paint coating from a small open flat area between Hi-Lok fasteners on both left and right, upper and lower FS 291.5 - FS 299.0 longeron splice fitting straps.

WARNING

CAUTION

Verification of aluminum straps will be accomplished. The reading for aluminum should be 30.5 – 36-percent International Annealed Copper Standard (IACS).

i. Perform Inspection 4, paragraph 6.2d, metal conductivity test on both left and right, upper and lower

FS 291.5 – FS 299.0 longeron splice fitting straps to determine metal composition, aluminum or steel, IAW TO 33B-1-2, WP 407.00, Measurement, Digital Conductivity and Nonconductive Coating Thickness, Table 1 and 3.

j. If any of the four longeron splice fitting straps do not meet the IACS chart percentages for aluminum, proceed but do not perform paragraphs 6.4a thru 6.4j on affected side (left, right or both) showing a non-aluminum IACS percent reading. Immediately report the specific IACS percent reading of the affected strap(s) IAW TO 00-25-107 for disposition and proceed with TCTO.

k. Remove all sealant from the FS 284.0 splice area between FS 284.0 and FS 299.0. Make sure inspection area is clean of grease, oil, dirt, chipped paint and other contaminants IAW TO 1T-38A/C-23. See Figures 5 and 6 for inspection area.

6.2 Inspections. Perform inspection method listed below for the areas outlined in 6.3a through 6.4o as required.

The performance of these inspections requires one inspector. This person shall be as a minimum, an Air Force Skill Code 2A752 or NAS-410 Level II certified.

a. Inspection 1 – Bolt Hole Eddy Current Aluminum. IAW TO 33B-1-2 WP 404.00, Eddy Current, Aluminum, Weakly Ferromagnetic and NonFerromagnetic Alloys, Rotary Fastener Holes for setup and calibration of equipment. IAW TO 33B-1-2 WP 404.00, Eddy Current, Aluminum, Weakly Ferromagnetic and

NonFerromagnetic Alloys, Rotary Fastener Holes, paragraph 4.5 or 4.6 Identifying Scanner Zero for crack locations.

b. Inspection 2 – Surface Eddy Current - Aluminum. IAW TO 33B-1-2, WP 402.00, Eddy Current, General

Surface, Aluminum, Weakly Ferromagnetic and NonFerromagnetic Alloys for setup and calibration of equipment.

c. Inspection 3 – Penetrant. IAW TO 33B-1-2 WP 201.00 Fluorescent Penetrant General Procedure, Solvent

Removable, Method C.

d. Inspection 4 – Material Conductivity. IAW TO 33B-1-2, WP 407.00, Measurement, Digital Conductivity and

Nonconductive Coating Thickness for Setup and Calibration of Equipment and Material Testing.

6.3 Maintenance actions and inspections for the FS 284.0 splice bolt areas.

Hi-Lok fastener in fuel cavity below barrel nut hole may be removed to facilitate removal of barrel nut and barrel nut retainer at FS 284.0. On some aircraft, the Hi-

Lok fastener above the FS. 284.0 barrel nut hole has been omitted and the barrel nut and barrel nut retainer can be removed from the top access hole without removal of

Hi-Lok fastener mentioned in paragraph 6.3a.

a. If required, remove Hi-Lok fasteners (one per side) from fuel cavity at FS 284.0 directly below barrel nut installation area to facilitate barrel nut and retainer removal and reinstallation. See Figures 5 and 6.

Remove only one FS 284.0 splice bolt at a time.

Install new serialized bolt in barrel nut assembly prior to removing opposite side FS

284.0 splice bolt to prevent possible misalignment of aircraft structure. Aircraft will not be left unattended and there will not be any maintenance, other than bolt and barrel nut hole preparation and inspection, accomplished while the FS 284.0 splice bolt is removed or damage to aircraft may result.

b. Using locally manufactured FS 284.0 Longeron Splice Bolt wrench (Ref. TO 1T-38A/C-3), remove FS 284.0 splice bolt P/N 84492-10-24, washer P/N MS200002C10, any additional spacer washers P/N MS200002C10 under the bolt head, barrel nut P/N NAS 577B10A and barrel nut retainer P/N NAS 578-10B. Retain old bolt until new serialized bolt has been permanently installed as per paragraph 6.3n, and then discard. Discard washers, barrel nut and barrel nut retainer and replace 100 percent.

c. Clean FS 284.0 bolt hole and longeron surface around bolt seat area IAW TO 1T-38A/C-23 prior to performing bolt hole eddy current scan and fluorescent penetrant inspection. Longeron surface must be free of paint and primer prior to fluorescent penetrant inspection. See Figures 1, 2 and 3 for inspection area that must be clean.

If using a Nortec 2000D+, the EXT SPLT display mode will be used for all bolt hole inspections. If using a Nortec 2000D, displays will require the operator to switch from the Sweep display to the Impedance display for all indications noted.

Indications may be noted at the end of the FS 284.0 longeron splice bolt hole scan located inside the barrel nut hole due to the curved surface. These indications should be disregarded; the end of the hole is performed separately in paragraph

6.3g.

If rejectable indications are noted in Steps 6.3d thru 6.3j, reinstall removed bolt, immediately report all suspect defects IAW TO 00-25-107 and proceed to inspect opposite side FS 284.0 longeron splice bolt hole.

d. Perform Inspection 1, automatic bolt hole scan for 5/8-inch bolt, of the FS 284.0 longeron upper splice bolt hole. See Figures 1 and 1A.

e. Perform Inspection 2, surface scan of the cockpit longeron along the inner edge, around the bolt hole and along the outer upper, inboard and outboard surfaces. Probe guide may be used if there is enough clearance and the top cap is lifted off of surface and scan is performed adjacent to the guide shaft. See shaded areas in Figures

1and 2. If defect is detected, perform Inspection 3/Method C penetrant inspection on all suspected defect areas

(may be combined with step 6.3f).

f. Perform Inspection 3, fluorescent-penetrant inspection, of blocked area in Figure 2 and shaded area in

Figure 3.

While scanning, pay close attention to where the FS 284.0 bolt hole and the barrel nut hole intersect. This intersection will cause two 80%+ FSH signals that appear on screen. See Figure 4A. These indications are not considered rejectable.

g. Perform Inspection 1 automatic bolt hole scan for 1 1/16-inch hole of the FS 284.0 longeron upper splice bolt barrel nut hole. See Figures 4 and 4A.

h. Scan barrel nut area. See Figures 4 and 4A. Scan entire 1 1/16-inch hole from the lower opening of hole while using your finger as a guide to identify/locate the opening of the FS 284.0 splice bolt hole intersection.

i. Rotate the SYNC ANGLE to place the two signals from FS 284.0 hole in the left side of the screen. See

Figure 4A.

j. Repeat entire hole scan from upper side of barrel nut hole to confirm inspection results. Possible defect indications will appear in the scan zone on the screen outside of the two FS 284.0 splice bolt hole edge indications. See Figure 4A.

The Plans and Scheduling Office of individual aircraft owning units will control and issue serialized numbers for FS 284.0 bolts in pairs consecutively for their individual aircraft. Odd numbered bolts on the left side of aircraft, even numbered bolts on the right side of aircraft.

k. Serialize new 284 bolt, P/N 84492-10-24. See Figure 8.

l. If there are any rejectable indications noted in paragraphs 6.3d thru 6.3j, reinstall original FS 284.0 bolt and barrel nut assembly IAW paragraph n, immediately report all suspect defects IAW TO 00-25-107 and proceed to inspect opposite side FS 284.0 longeron splice bolt hole, if not previously inspected. If there are no rejectable indications noted in paragraphs 6.3d thru 6.3j, install serialized new bolt P/N 84492-10-24. Corrosion treat bolt and washer(s) IAW TO 1T-38A/C-23.

m. Install new barrel nut P/N, NAS 577B10A and barrel nut retainer P/N NAS 578-10B.

After torquing bolt, ensure clearance exists between bolt and aft surface of barrel nut hole or damage to aircraft may occur.

n. Install bolt with washer(s) in barrel nut and retainer assembly and torque to 1500-1900 inch-pounds using locally manufactured FS 284.0 Longeron Splice Bolt wrench. Reference TO 1T-38A/C-3.

o. Comply with paragraphs 6.3a. thru 6.3n. for opposite side.

6.4 Maintenance actions and inspections for the upper longeron FS 284.0 splice fitting area inside the forward fuselage fuel cell from FS 284.0 thru FS 299.0 left and right.

EPOXY PRIMER MIL-PRF-23377 is toxic to skin, eyes and respiratory tract.

Skin/eye protection required. Avoid repeated/prolonged contact. Use in well ventilated areas. Keep away from open flames and other sources of ignition.

Extreme care will be taken to ensure FS 284.0 longeron splice fitting horizontal and vertical plates are not damaged by Hi-Lok removal tooling. All nicks and gouges to plate surfaces will be blended out and bare metal surfaces primed with MIL-PRF-

23377 or equivalent, IAW TO1T-38A/C-23 prior to sealing of forward fuel cell.

See Step 6.5a.

There are two known Hi-lok configurations on the upper vertical flange of the

FS 284.0 splice area between FS 284.0 and FS 299.0. See Figures 5 and 6.

a. Remove half of the HL18PB-6 Hi-Lok fasteners from the FS 284.0 splice plates between FS 291.5 and

FS 299.0 by removing every other fastener. See Figure 5 or 6.

b. Clean Hi-Lok fastener holes IAW TO 1T-38A/C-23 prior to performing inspection.

c. Perform Inspection 1, automatic bolt hole inspection of the fastener holes in horizontal flange and in the open hole below barrel nut opening if removed. See Figure 5 or 6 depending on configuration.

d. Perform Inspection 2, surface scan around Hi-Lok collars of all other fasteners in the upper and lower vertical flange from FS 284.0 to FS 299.0 and the collars that are within the 1-inch area adjacent to the frames at FS 284.0, FS 291.5 and FS 299.0. See Figures 5 or 6 depending on configuration.

e. Measure and install new fasteners, self-aligning washers and collars of inspected holes IAW

TO 1T-38A/C-3.

Do not attempt to remove Hi-Lok fasteners that are within 1- inch of FS 284.0 or on either side of the frame at FS 291.5 and the forward side of the frame at FS 299.0 or damage to aircraft may result. See Figure 5 or 6.

f. Remove the other half of the HL18PB-6 Hi-Lok fasteners from the FS 284.0 splice plates between FS 291.5 and FS 299.0. See Figure 5 or 6.

g. Clean Hi-Lok fastener holes IAW TO 1T-38A/C-23 prior to performing inspection.

h. Perform Inspection 1, automatic bolt hole inspection of fastener holes. See Figure 5 or 6 depending on configuration.

i. Measure and install new Hi-Lok fasteners, self-aligning washers and collars IAW TO 1T-38A/C-3.

Hardened liquid shim material may be present on the upper and/or lower edges of the FS 284.0 splice fitting. Do not attempt to remove this material. Surface eddy current inspect the splice fitting adjacent to the liquid shim material.

During the scan of the horizontal splice strap, an indication may appear in the upper right quadrant / Impedance Plane of the screen caused by the Hi-Lok on the vertical flange close to the hole being inspected. Any indications in this location are not cracks and may be disregarded.

j. Perform Inspection 2, surface scan the upper and lower splice fitting edges and the exposed edge of the horizontal flange to include edges of splice plates. See Figure 7.

k. Remove six Hi-Lok fasteners IAW TO 1T-38A/C-3 from the lower vertical flange of the FS 284.0 splice between FS 284.0 and FS 291.5. See Figure 5 or 6 depending on configuration.

l. Clean Hi-Lok fastener holes IAW TO 1T-38A/C-23 prior to performing inspection.

m. Perform Inspection 1, automatic bolt hole inspection on the six Hi-Lok fastener holes. If removed, also inspect the one Hi-Lok fastener hole identified in paragraph 6.3a. See Figure 5 or 6.

CORROSION INHIBITIVE SEALANT MIL-PRF-81733 is toxic to skin, eyes and respiratory tract. Skin/eye protection required. Avoid repeated/prolonged contact.

Use in well ventilated areas. Keep away from open flames and other sources of ignition.

n. Measure and install six new Hi-Lok fasteners removed in paragraph 6.4k plus the one Hi-Lok fastener removed in paragraph 6.3a, wet with sealant MIL-PRF-81733 or equivalent, IAW TO 1T-38A/C-3. See

Figures 5 and 6.

o. Repeat steps 6.4a. through 6.4n. for the opposite side.

6.5 Reassembly.

CORROSION INHIBITIVE SEALANT MIL-S-8802 is toxic to skin, eyes and respiratory tract. Skin/eye protection required. Avoid repeated/prolonged contact.

Use in well ventilated areas. Keep away from open flames and other sources of ignition.

Styrofoam plugs may be inserted into the upper and lower ends of the

1 1/16-inch barrel nut hole to prevent sealant from entering hole.

To facilitate future maintenance/inspection, ensure sealant does not enter the barrel nut hole.

a. Reseal forward fuel cell cavity previously stripped in paragraph 6.1h with MIL-S-8802 or equivalent, IAW

TO 1T-38A/C-3.

b. Install left and right electrical equipment racks IAW TO 1T-38A/C-2-7.

c. Install access door numbers 185 and 186 or 171 and 174 (door number depends on aircraft serial number) IAW TO 1T-38A/C-2-2.

d. Install forward fuselage fuel cell IAW TO 1T-38A/C-2-5.

All stress panels will be installed prior to any jacking, down-jacking and/or towing operation or damage to aircraft may result.

e. Down-jack aircraft IAW TO 1T-38A/C-2-1.

f. Install aircraft battery IAW TO 1T-38A/C-2-7.

g. Perform Testing AC Power Supply System IAW TO 1T-38A/C-2-7.

h. Perform dual engine run IAW TO 1T-38A/C-2-6 and TO 1T-38A/C-2-6-2.

6.6 Reporting. Immediately report all suspect defects IAW TO 00-25-107.

7. SUPPLEMENTAL INFORMATION.

7.1 Fuel System Defuel/Purge. Perform defuel/purge of fuel system prior to accomplishing this TCTO.

7.2 Operational Checkout Requirements. Functional Check Flight is not required.

7.3 Weight and Balance Information. There are no weight or balance changes resulting from the instructions contained herein.

7.4 Technical Manuals Affected. Not applicable.

Figure 1. Eddy Current Surface Scan Inspection Locations

FS 87.75

FS 144

FS 205.5

FS 264

UP

AFT

FS

A

A

UPPER COCKPIT

LONGERON

B

B

SECTION A - A

SPLICE BOLT

HOLE

INSPECT ACCESSIBLE AREAS

ALONG LONGERON OUTER

SURFACE (INBOARD, UPPER, AND

OUTBOARD) FROM FS 278.0 TO FS 284.0

OUTBD

UP

CORNER CRACK IN

SPLICE FITTING

INSPECT LONGERON INNER

SURFACE FROM FS 278.0 TO

FS 284.0

SECTION B-B

EYEBROW CRACK

AT END OF PAD

COUNTER BORE

AFT

UP

SPLICE BOLT HOLE

Figure 1A. Non-Relevant Eddy Current Indications

INSPECT INSIDE BOX AREA

SURFACE ET AND PT

Figure 2. Upper Longeron Splice Bolt Hole Exterior View

LEFT SIDE SHOWN

RIGHT SIDE OPPOSITE

VIEW LOOKING UP AND

AFT IN ACCESS PANEL

Figure 3. Penetrant - Inspection Location

FS 87.75

FS 144

FS 205.5

FS 264

DETAIL A – VIEW OF LEFT UPPER LONGERON SPLICE

UP

FWD

FS

B

B

SECTION B - B

OUTBD

UP

UPPER

COCKPIT

LONGERON

Figure 4. Bolt-Hole Eddy Current Barrel Nut Hole and Surface Splice Bolt End

DEFECT AREA IN THE SCAN ZONE

TWO INDICATIONS FROM FS 284.0 SPLICE BOLT HOLE

Figure 4A. Two Indications Caused by FS 284.0 Bolt Hole

DO NOT REMOVE HI-LOK COLLARS FROM ANY FASTENER LOCATED

WITHIN ONE-INCH OF FS 284.0, 291.5 AND 299.0 FRAMES, EXCEPT AS NOTED

IN THIS FIGURE. IT MAY NOT BE POSSIBLE TO REPLACE THE COLLAR OR

TO REMOVE THE FASTENER AFTER COLLAR REMOVAL. IT IS PERMISSABLE

TO REMOVE AND REPLACE COLLARS AS NECESSARY TO FACILITATE USE

OF BOLT HOLE EDDY CURRENT PROBE

VIEW LOOKING OUTBOARD AT AFT FS 284.0 SPLICE FITTING

VIEW LOOKING UP AT AFT FS 284.0 SPLICE FITTING

NOTE

ACTUAL FASTENER PATTERN MAY VARY FROM PATTERN

DEPICTED IN ILLUSTRATIONS

UPPER AND LOWER

SPLICE PLATES

SPLICE PLATE

Figure 5. Standard Configuration for Aft FS 284.0 Splice Fitting

(Shown with a single row of fasteners along the Upper Flange)

STANDARD CONFIGURATION SHOWING A SINGLE ROW OF

FASTENERS IN UPPER FLANGE OF SPLICE FITTING

BARREL NUT HOLE

FWD

UP

FWD

INBD

REMOVE THESE HI-LOK FASTENERS AND ACCOMPLISH BOLT HOLE EDDY

CURRENT NDI

LEAVE THESE FASTENERS AND HI-LOK COLLARS IN PLACE – SURFACE

EDDY CURRENT AROUND COLLAR

THIS HI-LOK FASTENER MAY REQUIRE REMOVAL FOR BARREL NUT

REMOVAL. ACCOMPLISH BOLT HOLE EDDY CURRENT NDI PRIOR TO

HI-LOK FASTENER REPLACEMENT. SEE NOTE, 6.3a FOR EXCEPTION

DO NOT REMOVE HI-LOK COLLARS FROM ANY FASTENER LOCATED

WITHIN ONE-INCH OF FS 284.0, 291.5 AND 299.0 FRAMES, EXCEPT AS NOTED

IN THIS FIGURE. IT MAY NOT BE POSSIBLE TO REPLACE THE COLLAR OR

TO REMOVE THE FASTENER AFTER COLLAR REMOVAL. IT IS PERMISSABLE

TO REMOVE AND REPLACE COLLARS AS NECESSARY TO FACILITATE USE

OF BOLT HOLE EDDY CURRENT PROBE

VIEW LOOKING OUTBOARD AT AFT FS 284.0 SPLICE FITTING

VIEW LOOKING UP AT AFT FS 284.0 SPLICE FITTING

NOTE

ACTUAL FASTENER PATTERN MAY VARY FROM PATTERN

DEPICTED IN ILLUSTRATIONS

UPPER AND LOWER

SPLICE PLATES

SPLICE PLATE

Figure 6. Non-Standard Configuration for Aft FS 284.0 Splice Fitting

(Shown with Double Row of Fasteners Along the Upper Flange)

NON-STANDARD CONFIGURATION SHOWING A DOUBLE ROW OF

FASTENERS IN UPPER FLANGE OF SPLICE FITTING

BARREL NUT HOLE

FWD

UP

FWD

INBD

REMOVE THESE HI-LOK FASTENERS AND ACCOMPLISH BOLT HOLE EDDY

CURRENT NDI

LEAVE THESE FASTENERS AND HI-LOK COLLARS IN PLACE – SURFACE

EDDY CURRENT AROUND COLLAR

THIS HI-LOK FASTENER MAY REQUIRE REMOVAL FOR BARREL NUT

REMOVAL. ACCOMPLISH BOLT HOLE EDDY CURRENT NDI PRIOR TO

HI-LOK FASTENER REPLACEMENT. SEE NOTE, 6.3a FOR EXCEPTION

VIEW LOOKING OUTBOARD AT AFT FS 284.0 SPLICE FITTING

VIEW LOOKING UP AT AFT FS 284.0 SPLICE FITTING

UPPER AND LOWER

SPLICE PLATES

SPLICE PLATE

Figure 7. Eddy Current Inspection Along Edges of the Aft FS 284.0 Splice Fitting

SURFACE EDDY CURRENT INSPECT APPROXIMATELY 1/8- INCH

FROM EDGES ALONG UPPER AND LOWER FLANGES OF REPAIR

FITTING. TYPICAL AS SHOWN IN SHADED AREAS.

FWD

UP

FWD

INBD

EDDY CURRENT INSPECT ALONG OUTBOARD EDGES OF

HORIZONTAL FLANGE AND SPLICE PLATES FULL LENGTH

OF REPAIR FITTING

Figure 8. FS 284.0 Bolt Serialization Template

IF THE FS 284.0 SPLICE BOLT P/N 84492-10-24 DOES NOT

HAVE A UNIQUE SERIAL NUMBER LOCATED ON THE

HEAD OF THE BOLT, A SERIAL NUMBER SHALL BE

ENGRAVED PER THE FOLLOWING BEFORE INSTALLING

BOLT: ENGRAVE A SERIAL NUMBER ON THE BOLT HEAD

IN THE LOCATION SHOWN IN FIGURE 8 BELOW. THE

SERIAL NUMBER WILL CONSIST OF A TWO LETTER

DESIGNATION FOR THE CURRENT AIRCRAFT BASE

LOCATION, FOLLOWED BY A 4-DIGIT NUMERIC NUMBER.

PREFIX THE SERIAL NUMBER WITH A MARKING OF “S/N”.

THE FIRST NUMERIC NUMBER USED AT EACH BASE

SHOULD BE 0001, AND IT WILL BE SEQUENTIALLY

INCREMENTED ON ALL ADDITIONAL NON-SERIALIZED

BOLTS BEFORE INSTALLATION. ODD NUMBERED BOLTS

ON THE LEFT SIDE OF AIRCRAFT, EVEN NUMBERED

BOLTS ON THE RIGHT SIDE OF AIRCRAFT. EXAMPLE:

BOLTS INSTALLED FOR RANDOLPH AFB, THE MARKINGS

FOR THE FIRST BOLT INSTALLED WILL BE S/N:RA0001

AND THE SECOND WILL BE S/N:RA0002, ETC

8. RECORDS.

8.1 Action Required on Maintenance Records.

a. Report TCTO compliance IAW TO 00-20-2, Chapter 3.

b. Annotate Pass/Fail and document IAW TO 00-5-15, Chapter 3.

c. Update AFTO Form 95 to show TCTO compliance.

d. The Plans and Scheduling Office of individual aircraft owning units will control and issue serialized numbers for FS 284.0 bolts in pairs consecutively for their individual aircraft. Odd numbered bolts on the left side of aircraft, even numbered bolts on the right side of aircraft.

The AFTO Form 95 will reflect the date and positioning, left or right, of the serialized bolts installed.

e. Report all non-standard FS 284.0 longeron splice fitting configurations (left, right, or both) as shown in

Figure 6, with aircraft serial number, to Zachary Whitman via e-mail Zachary.Whitman@Hill.AF.MIL and Michael Blinn via email Michael.Blinn@Hill.AF.MIL.

f. Report specific conductivity readings using IACS percentage chart for all non-aluminum FS 284.0 longeron splice fitting straps shown in Figure 5 or 6 (left, right, upper or lower) with aircraft serial number, to Zachary

Whitman via e-mail Zachary.Whitman@Hill.AF.MIL and Michael Blinn via email

Michael.Blinn@Hill.AF.MIL.

g. Immediately report all defects IAW TO 00-25-107.

8.2 Action Required on Supply Records. Not applicable.

8.3 Retrofit Change or Inspection Identification Marking. Not applicable.

BY ORDER OF THE SECRETARY OF THE AIR FORCE

NORTON A. SCHWARTZ, General, USAF

Chief of Staff

DONALD HOFFMAN, General, USAF

Commander, AFMC

Prepared by Steven Ames for OO-ALC/GHMEH, DSN 777-3320 mailto:Zachary.Whitman@Hill.AF.MIL mailto:Michael.Blinn@Hill.AF.MIL mailto:Zachary.Whitman@Hill.AF.MIL mailto:Michael.Blinn@Hill.AF.MIL