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As I know plane climb "with nose up", but can plane climb without change pitch angle?

Can I force plane to climb like this:

If I fly in straight level flight at 100km/h and now increase just speed at 180km/h without any change at tail/wing.

1.Will plane climb with no change in pitch angle?

2.Or maybe will plane pitch up by itself?

enter image description here

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    No idea what the question is asking, although if it's a play on words then the humor is both juvenile & inappropriate. Hopefully it isn't that, and just unclear. Either way, vtc. – Ralph J Jan 15 '21 at 22:38
  • @Ralph J the writer is struggling with pitch, AOA, and speed as many early builders do. We may wish to introduce the lift equation, which shows AOA effect on lift to be linear and velocity squared. The answer to the title is "yes", speed wins out and a plane can "levitate" without pitching up if it is trimmed a certain way. Though far less efficient than our "Vy", it can be done. – Robert DiGiovanni Jan 16 '21 at 04:38
  • Related -- https://aviation.stackexchange.com/questions/12714/why-do-airplanes-lift-up-their-nose-to-climb – quiet flyer Jan 16 '21 at 14:27
  • "without any change at tail/wing."-- you need to make it clear whether you are trying to say that the control surfaces on the wings and tail stay in the same position, or the aircraft stays in the same pitch attitude, after the speed increase. They are not the same thing, and both conditions cannot happen at the same time. You need to say which case you are asking about. (Or break it up into part a) and part b), one for each case.) Once you clear this up, it looks like you'll have a good question that is well suited for a good answer, if it is not a duplicate. – quiet flyer Jan 16 '21 at 14:39

3 Answers3

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Basically a plane will climb, descend or maintain altitude depending on two things: the angle of attack of the wing, and airspeed.

So, yes, it is possible to trasition from level flight to climb just by increasing speed, because as the speed increases, there is more airflow around the wing, and it will create more lift.

Also, generally planes have a natural tendency to pitch up if speed is increased and nothing else is done, further adding to the climb speed. Aeroplanes tend to "try" and maintain the speed they are trimmed to, hence the upward pitch as the plane is seeking to shed the excess airspeed by transitioning the extra energy into altitude gain.

Jpe61
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When a B-52G (or earlier) takes off, it pretty routinely does essentially no rotation, so it's level but climbing. For a couple of examples:


...it's difficult to be certain exactly when the aircraft become airborne. Granted, that's partly because visibility is poor--it's an old video (probably originally on VHS), and 8 water injected J-57 engines produce a lot of smoke/soot/steam. After gaining some altitude, they did usually pull the nose up a little, but it wasn't necessary, and wasn't always done.

A B-52H has enough more static thrust that it does often (usually?) do a mild rotation, but in at least some cases, it's still so mild that it's hard to be sure whether it's actually happening or not. For example:

Jerry Coffin
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  • Does wing feel downward airflow componet which reduce effective AoA when plane is climb like this( attitude for horizontal fligt)? –  Jan 16 '21 at 19:48
  • @EBV821: The wing has a pretty high angle of incidence, so with the fuselage level, you can still fly at a fairly high angle of attack. Although it's not visible in any of these videos, my personal recollection is that it's was pretty common (at least with a B-52G) that the nose was pointed somewhat downward, even during climbs. – Jerry Coffin Jan 16 '21 at 20:02
  • So B-52g can climb like my plane at picture in my post? I add picture... –  Jan 16 '21 at 20:41
  • @EBV821: Pretty much like than anyway, yes. My primary reservation is about your labeling of the angle of attack, which can/will vary depending on air movement (e.g., rising air could increase the angle of attack, independent of the aircraft's attitude relative to the ground). – Jerry Coffin Jan 16 '21 at 20:42
  • The reason is that the rear gear is so far behind the centre of gravity that the tail can't generate enough force to raise the nose until the weight has been almost completely transferred on the main wing anyway. Which means the wing has to be mounted at such incidence that it generates lift for take-off in the ground attitude. – Jan Hudec Jan 18 '21 at 06:51
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The answer is yes. And this is very easy to see in real aircraft.

Tail dragged aircraft are stuck to the ground during takeoff, because of their gear layout they cannot change their angle of attack very much or at all.

Yet when the aircraft starts its roll, it is on the ground, then at some point it picks up speed and starts climbing. This means that speed alone is indeed enough to make an aircraft climb without changing aoa.

Maury Markowitz
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  • Regardless of the landing gear arrangement, planes are lifted off the runway by pitching the nose up, not by increasing the speed alone. There may be very very very few exceptions to this. – Jpe61 Jan 16 '21 at 14:01
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    During ground roll the tail of taildraggers is lifted off the ground before actually rotating the plane off the ground. – Jpe61 Jan 16 '21 at 14:03
  • @Jpe61 -- usually but not always; there is such a thing as a 3-point takeoff, i.e. all wheels lift off at once. The answer would be improved by specifying that this technique is being used. The "bicycle" arrangement used on the B-52 and B-47 may be a better example though – quiet flyer Jan 16 '21 at 15:18
  • @Jpe61 - (reposted to fix typo) – quiet flyer Jan 16 '21 at 15:18