Patent ID: 6996969

Claim:
A multi-mode shutdown system for use with a fuel metering unit of an engine, comprising: (a) a shutoff valve operative to selectively block an output flow from the fuel metering unit; (b) a shutdown solenoid in fluid communication with the shutoff valve for selectively closing the shutoff valve; (c) an orifice for creating a minimum flow from the output flow from the fuel metering unit; and (d) a minimum flow solenoid in fluid communication with the minimum flow for selectively blocking a minimum flow path for the minimum flow to the engine, wherein: (i) during a normal operation mode, the shutdown solenoid opens the shutoff valve and the minimum flow solenoid blocks the minimum flow path to the engine such that the engine receives the output of the fuel metering unit; (ii) during a shutdown mode, the minimum flow solenoid blocks the minimum flow path to the engine and the shutdown solenoid closes the shutoff valve such that the shutoff valve blocks the output of the fuel metering unit to stop fuel flow to the engine; and (iii) during a minimum flow mode, the shutdown solenoid closes the shutoff valve, and the minimum flow solenoid opens such that the minimum flow passes to the engine via the minimum flow path.