Abstract: A timer usable in navigating and piloting an aircraft, the timer having a plurality of application modes for management of time and numeric data, including an approach mode, a fuel mode, a chronograph mode and a clock mode. Each application mode can drive independent but simultaneous time count sequences for use in flight management and navigation such as counting down approach times, fuel-tank switching intervals and other time sensitive events, as well as providing military time, standard time and UTC time.