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Embraer Legacy 650 with tail wing

The picture I took from here. If you want to see, just click the link, it will take you to the part I want to show and ask. What I want to know is its name and its function.

AirCraft Lover
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1 Answers1

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They are called strakes, they are available on lots of airframes and help cut down on dutch roll and increase vertical stability.

Here is a nice overview of the strakes on a king air with lots of cool diagrams on how they work.

For the Embraer Legacy they also can negate the need for a yaw damper on MEL lists which can help increase dispatch reliability:

Strakes have been added beneath the rear fuselage and vortillons beneath the leading edge of the wings to increase stability, especially because of the yaw produced by the winglets. Although the ventral strakes do detract somewhat from the aircraft’s clean lines, they make up for it in dispatch reliability, since the strakes can negate the need for a yaw damper on the MEL list for short periods. The strakes under the leading edges of the wings assist with air flow over the ailerons.

Dave
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    MEL = Minimum Equipment List. If one item on the MEL isn't working, the plane cannot legally fly. – Peter Kämpf Feb 16 '22 at 19:50
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    @PeterKämpf Weirdly, in practice the MEL is exactly the reverse. The document tells you what you CAN have inoperative in order to dispatch, and what limitations (i.e. no ETOPS with an inoperative APU, in the 737), if any, apply. Any item NOT listed in the MEL can not be deferred. For instance, nothing in the MEL states that "both engines must be operative," but since nothing in the document allows dispatch with an engine inop, they're both required. Ditto all hydraulic systems on the 737, all 5 hydraulic pumps, etc. Yeah, it's not at all what "minimum equipment list" means in plain English! – Ralph J Feb 16 '22 at 23:36
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    That said, Dave's point is correct that having the strakes means that the Y/D can be deferred for some length of time. Absent the strakes, it would be required for dispatch. – Ralph J Feb 16 '22 at 23:37
  • Thank you for your explanation. – AirCraft Lover Feb 17 '22 at 13:24