1T-38-848.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 compromises, 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 Department of Defense components only for Direct Military Support, 27 September 2010. Other requests for this document shall be referred to OO-ALC/GHMEH, HILL AFB, UT 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). Violation of these export laws are subject to severe criminal 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 contents or reconstruction of the document.

TO 1T-38-848

Data Code: 0106142 27 September 2010

NON-DESTRUCTIVE INSPECTION (NDI) OF STEEL

DORSAL LONGERON P/N 3-11413-1, -2, -3, -4 AT

FUSELAGE STATION (FS) 400.5 TO 424.5 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 affected system.

1. APPLICATION.

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

6300008241 6400013194 6400013196 6400013197 6400013210 6400013214 6400013216 6400013219

6400013230 6400013255 6400013257 6400013262 6400013272 6400013282 6400013283 6400013289

6500010317 6500010342 6500010361 6500010366 6500010378 6500010387 6500010388 6500010390

6500010394 6500010407 6500010413 6500010416 6500010420 6500010431 6500010434 6500010435

6500010442 6500010449 6500010460 6500010461 6500010463 6500010467 6500010468 6500010473

6500010474 6600004326 6600004330 6600004337 6600004354 6600004359 6600004365 6600004370

6600004381 6600004382 6600004385 6600008356 6600008380 6600008399 6600008400 6600008402

6600008403 6700014826 6700014827 6700014831 6700014833 6700014838 6700014840 6700014845

6700014850 6700014852 6700014854 6700014916 6700014917 6700014921 6700014924 6700014926

6700014927 6700014928 6700014930 6700014932 6700014935 6700014936 6700014939 6700014940

6700014942 6700014947 6700014953 6700014957 6800008096 6800008098 6800008101 6800008102

6800008110 6800008112 6800008114 6800008117 6800008118 6800008121 6800008130 6800008132

1T-38-848

1.2 Kit Applicability by Model and Serial Number. Kits are not required by this TCTO.

1.3 Proofing. Desktop analysis performed due to similarity with TCTO 1T-38-836. Verification was previously accomplished In Accordance With (IAW) TO 00-5-15, at Laughlin AFB Texas, on aircraft Serial Number

68-00008165 on 12 March 2010.

2. PURPOSE.

The purpose of this TCTO is to inspect the steel dorsal longeron for cracks between Fuselage Station (FS) 400.5 to FS 424.5 on at risk aircraft. The Aircraft Structural Integrity Program (ASIP) has determined these aircraft to be at risk for cracking.

3. WHEN TO BE ACCOMPLISHED.

Not later than 425 days after receipt of this TCTO. Failure to accomplish the work by expiration of the compliance period shall be justification for withdrawing affected system or equipment from service until compliance is accomplished. If the compliance period cannot be met before the TCTO rescission date, the performing organization will request an extended compliance period IAW TO 00-5-15.

3.1 TCTO RESCISSION DATE. The TCTO Rescission date is 26 September 2012, unless extended via TCTO supplement or notices received through the Reliabilityand 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. Not applicable.

5.1.2 Action Required on Items in Chiefs 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. Not applicable.

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.

6800008135 6800008136 6800008139 6800008143 6800008147 6800008150 6800008152 6800008159

6800008160 6800008162 6800008163 6800008164 6800008167 6800008171 6800008172 6800008173

6800008179 6800008180 6800008190 6800008191 6800008192 6800008193 6800008196 6800008198

6800008200 6800008202 6800008204 6800008206 6800008207 6800008208 6800008211 6800008213

6800008215 6800008217 6900007075 6900007076 6900007080 6900007087 7000001549 7000001553

7000001554 7000001561 7000001562 7000001563 7000001565 7000001568 7000001573 7000001576

7000001581 7000001585 7000001589 7000001950 7000001951 7000001953

5.2 Personnel Information and Requirements.

WORK PHASES AFSC SKILLS MAN-HOURS

Unpacking N/A 0.0

Disassembly 2A3X3 and 2A7X3 or equivalent

2.0

Installation 2A752 or NAS-410 Level II 4.0

Assembly 2A3X3 or equivalent 2.0

Operational Check 2A3X3 0.5

Total Man-Hours 8.5

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

Qty Stock Number Part Number Nomenclature Source

1 ea 6635-01-455-9520 9622124 Detector, Metal Flaw (2000D/2000D+) AF

Supply

1 ea NSL NRK-3S Eddy Current Standard (4340 Steel or approved equivalent)

Local

Purchase

1 ea NSL SPO5965

3/16-inch

Bolt Hole Probe Local

Purchase

1 ea 6635-01-500-5491

NSL

9744738 MiniMite

-OR-

9744668 Spitfire

Scanner, Automated High Speed Eddy

Current

AF

1 ea 5995-01-517-4738 9122090 Cable Assembly, 16 Pin Lemo or equivalent

AF

Supply

1 ea NSL 9222412 Probe PL/100kHz-500kHz/A or approved equivalent

Local

Purchase

1 ea 7510-01-536-5629 3M5480 or equivalent Tape, Pressure Sensitive Teflon (1/4 x

0.005)

AF

Supply

1 ea 6635-01-522-7853 MP905-50 Probe, Surface Eddy Current 90 Degree AF

Supply

1 ea 6635-01-111-1548 218406 Cable, Eddy Current, BNC to Microdot AF

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.

Observe all WARNINGS, CAUTIONS, and NOTES in referenced TOs that apply to the following steps.

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

CAUTION

On applicable T-38A/B-Model aircraft, to prevent damage to cable connector and/or cover panel on Altitude Incoded Measurement System (AIMS) antenna, the AIMS antenna cable must be disconnected at the antenna connector during removal of the panel. On T-38C-Model aircraft, to prevent damage to the cable connector and/or cover panel on the Global Positioning System (GPS) antenna, the GPS antenna coax cable must be disconnected at the antenna connector during removal of the panel.

No additional fasteners/hardware shall be removed other than those specified in paragraph 6b.

b. Remove and retain machine screws (18 ea), P/N Spec-51B293-4 (NAS1153-4) from the Number 6 dorsal cover P/N 2-11861-1, -501 or 3-11861-1, -503 and remove cover from aircraft IAW TO 1T-38A/C-2-1 and TO

1T-38A/C-2-2 for generic panel removal procedures.

c. Use of a nonmetallic scrapper is permitted for removal of excessive sealant and flaking primer. Chemically remove all paint and/ or primer when coating thickness is in excess of the limits defined in TO 33B-1-2, WP

403.00 Eddy Current, General Surface, Ferromagnetic Alloys. If necessary, chemically remove all paint or primer and clean area to be inspected of all foreign material, dirt, grease, oil, etc., using only those solvents and methods authorized by TO 1T-38A/C-23.

6.1 General Eddy Current Inspection Procedures for the Nortec 2000D/D+ when performing Manual SurfaceInspection of Magnetic Steel Parts.

The performance of these inspections requires one inspector. This person shall be as a minimum, an Air Force Skill Code 2A752, 2A772 or NAS-410

Level II certified Eddy Current inspector.

a. The dorsal longeron is constructed of 4130 or 4340 forged steel with cadmium plating. The NDI technician will perform an eddy current inspection using a Nortec 2000D/D+, inspecting from FS 400.5 to FS 424.5 on the vertical leg of both left and right longerons using a surface probe. See Figure 1.

b. Calibration: Reference TO 33B-1-2, WP 403.00 Eddy Current, General Surface, Ferromagnetic Alloys.

c. Inspection of Part – Surface Probe.

Periodically during the inspection and following the completion of all inspections, check the calibration standard to make sure the instrument remains within calibration limits.

1. Inspection Zone #1 – Scan top edge horizontal face of vertical leg. Use your fingers as a probe guide.

Follow steps 4.(a) through 4.(f) below. See Figure 1.

2. Inspection Zone #2 – Scan top edge vertical face of vertical leg. Using your fingers as a probe guide.

Follow steps 4.(a) through 4.(f) below. See Figure 1.

3. Inspection Zone #3 – Scan around fastener holes and rivet heads. Follow steps 4.(a) through 4.(f) below.

See Figure 1.

4. Inspection Zone #4 – Scan entire outboard vertical face of vertical leg. Numerous scan lines are required.

Index half the probe coil diameter between scan lines to ensure full coverage. Follow steps (a) through (f) below. See Figure 1.

(a) Place the probe on the part being inspected. The probe coil should be at least two probe diameters from the nearest edge. Make sure of good contact between the coil and part.

(b) Press the NULL key and hold the probe still until nulling is complete. Periodic nulling may be necessary during inspection to maintain the baseline at 10% FSH and 50% FSW. If the HPF is used the signal should be maintained at 50% FSH and 50% FSW.

(c) Scan the inspection area.

(d) Use the same scan speed as used during calibration. If numerous scan lines are required, index one half the probe diameter between scan lines to ensure full coverage, unless otherwise specified. Watch for indications on the display similar to those obtained during calibration.

(e) Any indication exceeding 30% FSH shall be considered rejectable and shall be evaluated as a defect indication. See Figure 2.

(f) If original calibration sensitivity requirements are not met following any calibration check, rescan all inspections accomplished since the last successful check of the calibration standard.

d. Marking and Evaluating.

1. Mark all repeatable crack-like indications distinguishable (separated) from background noise.

2. Lift-off indications will be essentially horizontal while crack indications will be vertical. See Figure 2.

3. Mark all suspect defects and proceed to Paragraph 6.2.

6.2 General Eddy Current Inspection Procedures for the Nortec 2000D/D+ when performing Rotary Fastener Hole Inspection of Magnetic Steel Parts.

CAUTION

Extreme care shall be taken to prevent damage to inspection probe due to nutplates on the backside of the longeron.

The performance of these inspections requires one inspector. This person shall be as a minimum, an Air Force Skill Code 2A752, 2A772 or NAS-410 Level II certified Eddy Current inspector.

a. Calibration: Reference TO 33B-1-2, WP 406.00, Eddy Current, Magnetic Steel, Rotary Fastener Holes.

b. Inspection of Part - Rotary Fastener Hole Inspection.

Standardization should be verified at least once every 10 minutes or at the completion of each side, whichever comes first. If the notch signal does not provide 70-90% vertical PTP deflection, repeat the standardization and inspection.

1. Inspection Zone #5 – Vertical Leg Fastener Holes. Follow Steps (a) through (h) below. See Figure 1.

(a) Visually verify the hole surface condition will not damage the probe during inspection and is free of any foreign material (e.g. grease, sealant, metal shavings).

(b) Inspect 18 holes, 9 on each side left and right of aircraft.

(c) Return to the DISPLAY menu. If using the Nortec 2000D+, press the SWEEP key until EXT SPLT appears in the display. The display should now be in the split screen mode (sweep display on the left and impedance plane display on the right). If the instrument does not have the EXT SPLT function, press the SWEEP key until SWEEP EXT appears on the display. This indicates the inspection is being performed in the sweep mode.

(d) With the scanner off, check probe fit in the holes to be inspected. The fit should approximate the fit in the Reference Standard. Remove the probe from the hole.

(e) Turn on the scanner and reinsert the probe in the hole. Inspect by slowly pushing the probe through the entire hole then pulling the probe slowly back through the hole. The probe must be kept perpendicular to the part surface during scanning. Move the probe slowly through the hole a minimum of twice during inspection.

(f) Monitor the sweep display for indications appearing similar to the reference notch response while translating the probe through the hole.

(g) The hole is considered uninspectable if the general surface condition causes noise signals greater than

20% vertical PTP on the sweep display. If noise exceeds 20% vertical PTP additional hole preparation and cleaning may be required prior to reinspection.

(h) Verify the instrument standardization after the detection of a crack indication by performing a sensitivity check . insert the probe into the appropriate reference standard hole and maximize the signal response received from the reference notch. The notch signal should exhibit a vertical signal within 70 – 90% PTP. If it does, the defect indication SHALL be considered valid and recorded. If the notch signal does not provide the required 70 – 90% vertical PTP deflection, repeat the standardization and inspection.

c. Marking and Evaluating.

1. Any repeatable indication that exhibits a response equal to or greater than 40% vertical PTP in the sweep display and exhibits a phase response similar to the reference notch when viewed in the impedance plane display shall be rejected.

2. Non-relevant indications resulting from nicks, scratches or gouges will exhibit a different phase direction than a crack. Phase shape and direction for these indications will also vary from reference standard defect.

Note any visually observed nicks, scratches, or gouges.

3. Identify the clock position of any rejectable indication by using the sync angle IAW TO 33B-1-2, WP

406.00, Eddy Current, Magnetic Steel, Rotary Fastener Holes.

4. Mark all suspect defects noted in Paragraphs 6.1 and 6.2 and proceed to Paragraph 6.3, Backup

Procedures.

6.3 Backup Procedures. There are no backup procedures. Contact OO-ALC/GHMEC IAW TO 00-25-107 for disposition on all suspect defects.

6.4 Reassembly.

a. Upon completion of the NDI inspection, treat longerons to prevent corrosion, IAW TO 1T-38A/C-23.

b. On applicable A/B-Model aircraft, perform AIMS operational check of antenna IAW TO 1T-38A-103, Chapter 6 before panel is sealed. On C-Model aircraft, perform Embedded Global Positioning System/Inertial

Navigation System (GPS/INS) (EGI) and Radar Altimeter (RALT) System operational check of antenna IAW

TO 1T-38C-2-10, Chapter 3 before panel is sealed.

For T-38C model aircraft only, an embedded GPS and INS operational check is required. This is to insure a proper connection of the magnetic azimuth detector cable to the panel. This shall be conducted before panel is sealed.

c. On applicable A/B-Model aircraft, reconnect AIMS antenna cable to connector. On C-Model aircraft, reconnect GPS antenna cable to connector.

d. Apply sealant lAW TO IT-38A/C-3. Install the door using the proper length screws to hold the panel in place and properly torque IAW TO 1T-38A/C-3. Remove excess sealant from panel.

6.5 Reporting. Upon discovery, immediately report all suspect defects IAW TO 00-25-107.

(Fastener Holes) View Looking Inboard

Dorsal Longeron Inspection from FS 400.5 to FS 424.5 (Under Dorsal Cover #6)

Figure 1. Dorsal Longeron Inspection Area

Figure 2. Rejectable Indication

7. SUPPLEMENTAL INFORMATION.

7.1 Fuel System Defuel/Purge. Defueling/purging of the fuel system is not required prior to accomplishing this

TCTO.

7.2 Operational Checkout Requirements. For T-38C Aircraft only, conduct embedded GPS and INS operational check, IAW TO IT-38C-2-10. 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.

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.

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 Gary Ash, OO-ALC/GHMEH, DSN; 586-6464