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This is a questions about fixed-wing aircraft in general -- commercial planes and smaller. I have seen on a video that planes are capable of flying in a holding pattern with an nose-down attitude "for greater passenger comfort".

So, what are the advantages and disadvantages of level flight (not descent) with a nose down attitude?

And for what reasons do pilots fly like this?

Krishnaraj Rao
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1 Answers1

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Generally, a slight nose-up attitude gives the best performance. This allows the fuselage to create some lift without producing too much drag, thus filling the drop in the spanwise lift distribution created by the interruption of the wing by the fuselage. However, in passenger aircraft this will make the job of attendants much harder because their trolleys need to be pushed uphill and will roll away when not secured.

Therefore, a neutral attitude is preferred in cruise. When the aircraft slows down, it needs to increase its angle of attack, so the nose-up attitude results. When flaps are deflected, the zero-lift angle of attack is reduced, so a smaller angle of attack will again be possible. The precise attitude is a side effect of speed, air density and flap settings, and is not deliberately controlled when flying a holding pattern. By this time the flight attendants have returned to their jump seats, anyway.

Note that some aircraft will fly a nose-down attitude by design. The Boeing B-52 has powerful flaps which are designed to allow it to lift off without rotating, and when the aircraft accelerates during the initial climb after take-off or flies its approach, the fuselage will have a nose-down attitude. See the picture below of the B-2, the B-1B and the B-52 all flying at the same speed, each with its own fuselage attitude.

B-2, B-1B and B-52 flying at the same speed

B-2, B-1B and B-52 flying at the same speed (picture source).

Peter Kämpf
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    Precise attitude is also affected by weight, so if an aircraft is designed to avoid flying with negative pitch, it will necessarily fly with some positive pitch when heavily loaded. – Jan Hudec Oct 05 '15 at 09:48
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    @JanHudec: The B-52 will be flown at its optimum lift coefficient, and its cruise altitude will be a consequence of loading - it simply would not climb any higher. At low speed, the loading is reflected in the choice of airspeed, and again the lift coefficient would be the same, regardless of loading. Thus, pitch will only change with loading if both speed and altitude are prescribed. – Peter Kämpf Oct 05 '15 at 12:40
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    I mean more a typical airliner. But it's true they will also climb higher when lighter. – Jan Hudec Oct 05 '15 at 12:46
  • @PeterKämpf: ...as is typically the case whenever you're somewhere with air traffic control. – Vikki May 03 '19 at 03:02