Wingtip devices are usually intended to improve the efficiency of fixed-wing aircraft. There are several types of wing tip devices, and although they function in different manners, the intended effect is always to reduce the aircraft's drag by partial recovery of the tip vortex energy. Wingtip devices can also improve aircraft handling characteristics and enhance safety for following aircraft. Such devices increase the effective aspect ratio of a wing without materially increasing the wingspan. An extension of span would lower lift-induced drag, but would increase parasitic drag and would require boosting the strength and weight of the wing. At some point, there is no net benefit from further increased span. There may also be operational considerations that limit the allowable wingspan (e.g., available width at airport gates).
Wingtip devices increase the lift generated at the wingtip (by smoothing the airflow across the upper wing near the tip) and reduce the lift-induced drag caused by wingtip vortices, improving lift-to-drag ratio. This increases fuel efficiency in powered aircraft and increases cross-country speed in gliders, in both cases increasing range.U.S. Air Force studies indicate that a given improvement in fuel efficiency correlates directly with the causal increase in the aircraft's lift-to-drag ratio.
It wasn't particularly gracious
Of me to leave, but I found
The situation unbearably ostentatious
With you and her flirtatious
Had it been any other night
I might have stayed and put up a fight
I guess I wasn't impressed with your seduction
It wasn't an unlikely conclusion
For me to draw when I saw
You and her in some obvious love seclusion
Please pardon my intrusion
Had you said something too profound
I might have hung in and stood my ground
I guess I just wasn't digging our illusion
If you think I didn't see
I got news for you
If you think you're fooling me
I got news for you
It wasn't an irrational notion
That made me take the walk 'cause
I'm not inclined towards unwarranted commotion
Unnecessary motion
Had I thought you were some excuse
I might have stayed and turned on the juice
I guess I just felt a lack of real emotion
If you think I didn't see
I got news for you
If you think you're fooling me