On a wing, a wing tip vortex is unavoidable no matter what configuration you use, but does a vertical stabilizer form a wing tip vortex? I noticed this picture and saw two vortices coming off of the vertical stabilizers, so was this a result of moving the rudder or does the vertical stabilizer generate lift just like an aircraft wing?
-
$\begingroup$ I resized the image for you, it helps to make the question clearer $\endgroup$– PondlifeCommented Oct 2, 2015 at 0:50
-
$\begingroup$ @Pondlife How did you resize the photo? $\endgroup$– EthanCommented Oct 2, 2015 at 0:52
-
$\begingroup$ I saved it to my desktop, opened it in an editor (Paint, in this case) resized it and saved it again. $\endgroup$– PondlifeCommented Oct 2, 2015 at 0:54
-
1$\begingroup$ Well you're somehow contradicting yourself. If you can't prevent the formation of a vortex on a wing, then any control surface being a wing, you can experience a vortex too. To be accurate: you cannot prevent a vortex when creating lift with a finite length wing. $\endgroup$– minsCommented Oct 2, 2015 at 7:13
-
$\begingroup$ Good explanation of how the vertical stabilizers are used $\endgroup$– foootCommented Oct 2, 2015 at 17:36
1 Answer
In general, the vertical stabilizer and rudder create a symmetric airfoil. As there is no pressure difference between the two surfaces of the vertical stabilizer, vortices doesn't form, unlike the wing, which is designed to produce lift at normal angles of attack (it is usually cambered, producing lift at zero angle of attack).
You're correct that the vortices are generated due to the movement of rudder. Usually, vertical stabilizer doesn't create vortices unless rudder is deflected.
Note: Though I can't be sure, I think the F-22 is braking (the F-22 does not have a dedicated surface for braking like F-15 and uses the normal flight control surfaces). A similar thing happens in the following figure
Source: f-16.net
Only one F-22 (second from top) is using its control surfaces, probably for braking, resulting in vortices from the vertical stabilizer.