Climb with negative pitch

[SteveSmith]

I'm not a pilot (unless you count MS Flight Sim, which of course you don't), so forgive me if this is a stupid question, it's just a random thought that occured to me on a long motorway journey.

I do understand the basic physics behind how planes fly, so I know that the relationship between pitch and vertical speed is not a simple one, i.e. a plane won't necessarily go upwards if you point it's nose up.

However, is the opposite true? Are there planes that can climb with a negative pitch (i.e. nose down), given enough airspeed and the right configuration? If so, is this common?

Thanks,

Steve.

[Intruder]

It is common in helicopters.

The biggest example I can think of is the B-52 after takeoff. The flaps are so big and give the wing so much effective camber that the airplane pitches down after takeoff.

[Porrohman]

Many aircraft appear to fly with a nose down attitude when full flaps are deployed. F27, Belfast, AN22, spring to mind. If there's enough excess power available to overcome the drag caused by full flaps and whatever payload and fuel they are carrying, I imagine that they could be made to climb in that configuration with a slight negative pitch but it's not a particularly efficient way to gain altitude.

[corsair]

Don't confuse a nose down attitude with a negative pitch angle. It's all about the relative airflow over the wing. People often ask about how wings generate lift upside down. The wings generate lift, for that you need a positive pitch angle, relative to the airflow. Ignore the fuselage.

This is the F8 Crusader. It had a variable incidence wing so that the pilot had a better view on approach while still attaining maximum lift. I imagine, (without any evidence admittedly) that if it's wing was deployed in level flight that the aircraft would display a distinct nose down aspect despite flying straight and level.

[Intruder]

Don't confuse a nose down attitude with a negative pitch angle.

Hard to do, since they are the same...

Pitch angle is relative to the aircraft longitudinal axis; so is "nose down attitude."

Wing angle of incidence (and thus the AoA) of a clean wing may vary slightly so that the fuselage is at the lowest drag angle in normal cruise.

Extension of flaps may significantly increase the effective camber, angle of incidence, and AoA of the wing with a constant pitch angle.

[snips]

Roll the aircraft inverted and then climb.

That'll give you -ve alpha and a climb

I'll get my coat

[TyroPicard]

-ve alpha, yes ... but surely positive pitch?
TP

[adverse-bump]

Most wings will still generate lift at -4 alpha. so yes, if you had enough speed it would climb with a neg alpha.

as for nose down pitch, check out the dash 8 with flap 35, its about 8* nose down!!!!

[barit1]

Angle of attack (AOA or alpha) determines lift.

Angle of incidence determines the fuselage attitude (body angle, "pitch",...)

If the two are equal, the fuselage will be aligned with the relative wind; if altitude is held constant, then the fuselage will be level.

But vary the airspeed, altitude, etc. and the fuselage will be either nose up or down.

[AircraftOperations]

I was told that the new Embraer airline family can keep climbing with their nose pointing down in certain circumstances.

Comes down to momentum I was told.

[con-pilot]

The B-52 climbs in an observed nose down condition under some circumstances. The wing, however, has a positive angle of attack allowing the aircraft to gain altitude.