A HYDROMECHANICAL UNIT (HMU), A COMPONENT OF AN AIRCRAFT ENGINE SYSTEM. THE HMU RESPONDS TO ELECTRICAL SIGNALS FROM AN EEC TO METER ENGINE FUEL FLOW AND MODULATE MOTIVE FLOW TO SIX EXTERNAL HYDRAULIC SYSTEMS. A COMPONENT IN THE HMU CAUSES SERVO POSITIONING OF THE UNIT MV. THE MV POSITION ESTABLISHES THE PROPER METERED FUEL DELIVERY ORIFICE FOR THE COMMANDED FUEL FLOW. A MECHANICAL OVERSPEED GOVERNOR SWITCH LIMITS ENGINE SPEED TO 106 PERCENT MAXIMUM.

CLASSIFICATION HAS BEEN DETERMINED IN ACCORDANCE WITH THE FOLLOWING:- GENERAL INTERPRETATIVE RULES (GIR)S GIR 1 HAS BEEN USED TO CLASSIFY THIS PRODUCT BY THE TERMS OF HEADING 9032 - AUTOMATIC REGULATING OR CONTROLLING INSTRUMENTS AND APPARATUS GIR 6 HAS BEEN USED TO CLASSIFY THE GOODS TO SUBHEADING LEVEL 9032 89 - OTHER INSTRUMENTS AND APPARATUS: OTHER THAN HYDRAULIC OR PNUEMATIC TARIC 90328900 10 - FOR USE IN CIVIL AIRCRAFT ALSO CLASSIFIED IN ACCORDANCE WITH:- NOTE 7 (A) TO CHAPTER 90 HARMONIZED SYSTEM EXPLANATORY NOTES (HSEN) (I) TO HEADING 90.32