TM 10-1670-305-23&P GENERAL INFORMATION 0001  00 LIST OF ABBREVIATIONS ECP Engineering Change Proposal EMP Electromagnetic Pulse F Fahrenheit   Fig Figure ft Feet FT MSL Feet Mean Sea Level Ft/sec Feet per second GFD Ground H Height HCI Hardness Critical Item Hz Hertz lbs Pounds LED Light Emitting Diode MAC Maintenance Allocation Chart MSL Mean Sea Level No. Number NSN National Stock Number PIS Placed In Service P/N Part Number PMCS Preventive Maintenance Checks and Services PSI Pounds per Square Inch Pwr Power ROD Report of Discrepancy RPSTL Repair Parts and Special Tools List Sec Second SMR Source Maintenance Recoverability Sol Solenoid SRA Specialized Repair Activity Sup Supply TDR Transportation Discrepancy Report TM Technical Manual U/M Unit of Measure UOC Usable On Code VAC Volts Alternating Current Vac Vacuum W Width WP Work Package SAFETY, CARE AND HANDLING Observe normal precautions to prevent any unit from being subjected to unusual jolts and dropping. CALIBRATION Calibration, testing and certification shall be performed at intervals specified in indicated work packages: Automatic Ripcord Release, Model 451 – WP 0018 00. Test Chamber Assembly, Model 452 – WP 0018 00 0001 00-3/4 Blank Change 1