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Why not?
It has the same avionics...powerplant....mmm...ice protection? Does the XL have boots?
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The Excel has quit a few differences over 500 series. The larger engine have EECs (Electronic Engine controls) with throttle detents like FADECs. There are about twice as many annunciators as the 500s. The Excel also has a hydraulic, moveable horizontal stabilizer.
Throw in trailing link gear, heated leading edges, and an APU.
Hey, just to clarify, are you sure you meant the Excel? Or are did you really mean the Encore? The Encore DOES share the 500 type rating.