Control of both outflow valves, coupled with new nose cone vent, helps minimize pressurization surges. Outflow valves are controlled to close at a rate that insures smooth initial pressurization of cabin for improved passenger comfort. Models 681, 685, 690.
Modification provides an accurate indication of each propeller boot operation and an accurate visual indication that propeller deicer system is operating within designed electrical load limits for Models 680T, 680V, 680W, 681.
Modification provides an improved cabin door seal assembly that allows a more positive door seal and smoother door operation for Models 680T, 680V, 680W, 681.
Modification approved for ?All-Weather? flight conditions with new visual speed control indicator and ?Tellite? switch installations for Models 500A, 500B, 500U, 560F, 680F, 680FL, 680FL(P), 680F(P), 680T.
Provides night flying safety feature by illuminating wing leading edge. Models 500A, 500B, 500S, 500U, 560F, 680F, 680FL, 680FL(P), 680F(P), 680T, 680V, 680W, and 681.