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Since they are essentially an annular wing, how much do they contribute if at all to an aircraft's total lift? Would the effect of this lift be noticeable enough to help cancel out the drag they produce?

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Most jet nacelles contribute little or no lift, but there is at least one highly notable exception.

The airflow inside the nacelle is dominated by the engine and any chance to create differential pressure between upper and lower leading sections is kept negligible in order not to disrupt the intake flow.

The outside is more of a stubby fuselage than an annular wing and low drag dominates the design. The avoidance of interference with the leading edge of the wing, part way along and just above, is also a major consideration for the upper profile. Lift is not really considered, and is not present to any significant extent.

Having said that, for a large high-bypass turbofan, when placed well forward the lifting area can become significant at high angles of attack (whether positive or negative). It can be powerful enough to move the centre of lift forwards, reducing pitch stability and at steep angles leading to a tendency for the angle to diverge further. When Boeing were developing the Max variant of the 737, its new engines suffered just this problem on takeoff and landing. Boeing's solution was to introduce a Manoeuvring Characteristics Augmentation System (MCAS) which automatically operated the elevator to reduce the angle sharply if it got too steep. Tragically, in their hurry they botched the job, two commercial flights crashed fatally and the 737 Max has been grounded indefinitely until they can get a fix certified.

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Almost any sort of body, conveniently oriented in a fluid flow, can produce lift. A ball is one of the few exceptions...

Please note that lift and drag do never cancel out, because they are –by definition– vectors at 90º...

There are wingless, heavier-than-air aircraft, like this one, for example:

https://en.wikipedia.org/wiki/Wainfan_Facetmobile

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    $\begingroup$ You may get a little "rise" from a ball if it is spinning. $\endgroup$ – Robert DiGiovanni Oct 1 at 18:03
  • $\begingroup$ It would produce lift if it where spinning in a convenient way, driven by an external source of torque, so that it might drag the air layers close to its surface, that circulation generating lift. But in the absence of a external torque to produce that spin, I don't think that the ball might spin, and in the absence of spin, there would be no circulation, and hence no lift... $\endgroup$ – xxavier Oct 3 at 18:40
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    $\begingroup$ Agree with that. A golf ball does have spin imparted by the club, producing the Magnus effect. $\endgroup$ – Robert DiGiovanni Oct 3 at 20:27
  • $\begingroup$ Most balls have sufficient angular momentum to spin throughout their flight. The phenomenon of spin is extremely familiar to sports players and to cannon and musket gunners. Preventing a ball from spinning is a harder problem than getting it to spin, so there is almost always circulation and lift in one direction or another orthogonal to the flight path. It is known as the Magnus effect. $\endgroup$ – Guy Inchbald Oct 7 at 20:27
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To see the nacelle as an annular wing, you must get rid of the engine that is inside the nacelle. Technically xxavier is correct when saying that any body can create lift. But the nacelle and its installation are more known to disrupt the flow around the aircraft wing reducing its lift than a mean to increase lift of the aircraft at a given AOA.

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