This copy is a reprint which includes current pages from ...

1 This copy is a reprint which includes currentpages from Change 1.*TM 1-1500-204-23-7 TECHNICAL MANUALAVIATION UNIT maintenance (AVUM)AND aviation INTERMEDIATEMAINTENANCE (AVIM) MANUALFORGENERAL AIRCRAFT maintenance (NONDESTRUCTIVE TESTING AND FLAW DETECTIONPROCEDURES AND PRACTICES)VOLUME 7*This manual together with TM 1-1500-204-23-1 through TM 1-1500-204-23-6 and TM 1-1500-204-23-8 through TM 1-1500-204-23-10, dated 31 July 1992, supersedes TM 55-1500-204-25/1, dated 6 April 1970, including all STATEMENT A: Approved for public release.

2 Distribution Is , DEPARTMENT OF THE ARMY31 JULY 1992TM 1-1500-204-23-7C 1 CHANGE HEADQUARTERSDEPARTMENT OF THE ARMYNO. 1 WASHINGTON, , 30 December 1993 aviation UNIT maintenance (AVUM)AND aviation INTERMEDIATEMAINTENANCE (AVIM) MANUALFORGENERAL AIRCRAFT maintenance (NONDESTRUCTIVE TESTING AND FLAW DETECTIONPROCEDURES AND PRACTICES)VOLUME 7 DISTRIBUTION STATEMENT A: Approved for public release; distribution is 1-1500-204-23-7, 31 July 1992, is changed as and insert pages as indicated below.

3 New or changed text material' is indicated by a vertical bar in themargin. An illustration change is indicated by a miniature pointing pages Insert pagesi and ii i and ii1-1/(1-2 blank) 1-1/(1-2 blank) this sheet in front of manual for reference purposes. By Order of the Secretary of the Army:GORDON R.

4 SULLIVANG eneral, United States ArmyChief of StaffOfficial:MILTON H. HAMILTONA dministrative Assistant to theSecretary of the Army05900 Distribution: To be distributed in accordance with DA Form 12-31-E, block no. 3302, requirements for TM 1-1500-204-2 GOVERNMENT PRINTING OFFICE: 1994 - 510-106-00002TM 1-1500-204-23-7 PRECAUTIONARY DATAP ersonnel performing Instructions involving operations, procedures, and practices which are included or implied in thistechnical manual shall observe the following Instructions. Disregard of these warnings and precautionary information cancause serious Injury, death, or an aborted , CAUTIONS, and NOTES are means of attracting attention to essential or critical information in a are outlined as follows:WARNING: An operating or maintenance procedure, practice, condition, statement, etc.

5 , which if not strictly observed,could result in injury or death of : An operating or maintenance procedure, practice, condition, statement, etc., which if not strictly observed,could result in damage to, or destruction of, equipment or loss of mission effectiveness or long term health hazards An essential operating or maintenance procedure, condition, or statement, which must be TESTSE lectrical power up to 500 volts is used in testing the equipment. Exercise extreme caution during these EQUIPMENTAll switches and electrical equipment shall be of the enclosed explosion-proof type.

6 All metal apparatus shall begrounded to avoid the danger of Igniting test fluid fumes or creating electrical SOLVENTS/PAINTSS tandard precautions such as fire prevention and adequate ventilation shall be exercised when using solvents orapplying primer and coating Wear gloves or gauntlets when handling solvents as solvents may cause skin and solvents used to repair liferafts are flammable and shall be treated as such Never smoke or permit anytype of open flame near when using cements or (methylene chloride) vapor is heavier than air; adequate ventilation shall be provided for workingpersonnel.

7 Dichloromethane (methylene chloride) is toxic when vapors are inhaled over an extended period of monomer and polymer base adhesive, MIL-A-8576, contains a volatile liquid which may prove toxic when vaporsare inhaled over extended periods. Use only with adequate fire precautions when using aliphatic naphtha, Federal Specification 1-1500-204-23-7 HANDLING PLASTICSWear gloves to protect hands while handling hot plastic. Boiling water shall not be used for heating acrylate adequate ventilation when working with Furane Plastics, Epocast H-991-A, Furane hardener 941, or equivalentsas these materials are OILL ubricating oil, MIL-L-7808 or MIL-L-23699, contains an additive which is poisonous and absorbed readily through theskin.

8 Do not allow oil to remain on skin any longer than servicing aircraft or support equipment, clean up spilled fuel with cotton mops or cotton rags. Wash off any fuel onhands, body, or ACIDWear protective clothing when mixing acid with water. Always pour acid into water, never water into ALLOY FIREDo not use water or any standard liquid or foam-type fire extinguishers on a magnesium alloy fire, as they may cause anexplosion. Use dry sand or talcum powder, Federal Specification CORROSIONTake precautions to prevent possible dust explosions when removing corrosion from steel alloys.

9 Use goggles or faceshield when removing paint or corrosion with a wire brush or by the grinding AND WHEELSIf it is necessary to approach a wheel with a hot brake, do so either from directly In front or directly behind the extreme caution when prying out foreign material imbedded in tire not use air bottles or booster pumps not designed for tire SYSTEMDo not allow petroleum base products to come in contact with oxygen system components, as an explosion or fire not use masking tape to seal openings in oxygen regulators Masking tape constitutes a safety hazard when used oneither serviceable or repairable oxygen not use drycleaning solvent, Federal Specification P-D-680, near oxygen storage or transfer systems, the combinationof these two will form a highly explosive mixturebTM 1-1500-204-23-7 GROUND SUPPORT EQUIPMENTDo not attempt to lift any load when the hydraulic axle jack is tilted.

10 To prevent accidental falls, appropriate maintenanceplatforms/safety stands Illustrated in appropriate workstand manuals or any other approved locallyprocured/manufactured safety stands/restraint equipment will be used when working (above 10 feet) on aircraft In a non-tactical safety lock when an adjustable-height maintenance platform is In useEnsure the air hose used with compressed air is safe for the pressure being air pressure In air compressor tank before performing maintenance on air compressorsDisconnect power before changing belts on electrically-driven electrical power before opening or disassembling any part of electrical EQUIPMENTE xercise extreme caution when performing radiographic Inspections to prevent personnel from coming in contact withradiation.