pitch?

[Wally]

Hey all!

just have a little question for whoever knows the answer!!!

Whenever i fly, in any aircaft, at ,my cruising altitude, the nose of my plane always seems to be pitched a few degrees up.. ranging from
just one to sometimes 5-6 degrees! i dont know why, because when this happpens i always try to go faster for the nose to pitch down
again.. but as i reach my max speed its still up there!!! I'm very careful when loading the aircaft that the back is not heavier than the front,
and most of the time i make the front heavier, to get the nose down, without much success!!! its the worst with my Fokker 50 i used to fly
when starting up with my company, and now with my a321 its not as bad anymore.. but still! How do i solve this problem!!!???


Thanx for taking the time!

[gronji2004]

Try your rudder trim I think its called. It may lift your nose slightly.

[Wally]

Im on autopilot.. it should be doing that for me...! Should it not?

[gronji2004]

Sometimes AP can change the trim settings quite drastically. Its worth a check. My aircraft crashed becuase AP trimmed too much!

[Dutch64]

There is usually some pitch up during flight. If it's too much then the flight dynamics are not correct.

[Wally]

Thanx for the advice guys!!! Appreciated

[Jetflyer]

It is normal. The airfoil develops most of its lift at a certain angle of attack, usually around 5-7 degrees in the cruise. The pitch attitude is not
the same as the angle of attack, and the wing is angled to the fuselage already, further complicates matters.
attack. This angle of the wing to the fuselage is called the "angle of incidence", and is usually about 2-3 degrees. If the nose is level at a given attitude, the angle of attack is still about 2-3 degrees due to the angle of the wing to the fuselage. Some aicraft have a larger than usual angle of incidence, meaning a less large piytch attitude in the cruise, since the angle if attack of most airliuners' isd roughly tne same on most airliuners. The slower you go at a given weight, the larger the angle of atack
needs to be, and thus the resulting pitch attitude is higher, while the faster you go, the lower the angle of attack needs to be.

This will explain it all:

http://www.aerospaceweb.org/question/aer...0165.shtml

*sorry if this is all a bit vague, i am on the phone as i typ this. this is also the reaosn for the spelling mistakes.



Post Edited ( 10-31-06 01:12 )

[Ceemosp]

To add to Jetflyers post: For that reason the wings are actually mounted in an angle upwards in reference to the fuselage (if you are
looking at the wing profile in a whole) so when your wings just have the right angle of attack for maximum lift vs. airspeed your fuselage
will be pointing even more 't'wards the stars'

Some aircraft - especially some designed for STOL operations - will have this 'feature' even more pronounced.

Greetz Carsten

[Wally]

great info guys :D seem to be learning more by the minute!!!!

[Launchbury]

Most airplanes fly with a positive pitch, how much depends on the individual aircraft. The faster you fly, the less pitch required to maintain
altitude. If you are flying a jet then you are not going fast enough. Try Mach .80 and see what happens. If you are flying a prop, then that's
just how things go.

[gronji2004]

Mach .80? Check your overspeed limit first. Even my A330 cant do that .

[Launchbury]

What a hunk-o-junk! Even my ancient 727 cruises at Mach .81 and maxes at .86! My advice: Get something that doesn't suck.

[Tipath]

A couple of days ago I lost #1 engine (bird strike) on climb out from KSFO. When things settled down and I was being vectored to 19L I
went to spot view and WOW it is a wonder I hadn't stalled, the nose was really up. I hit the 7 key several times and she pretty much
returned to level.

As best as I can recall this is about the configuration when I noticed my out of trim CRJ.

3500 AGL
140 IKAS
8% flap

The gear was up at this point. I didn't want anymore flaps or gear until I was sure I had the runway made.

Best Regards

[Launchbury]

You would have been okay I think. If I recall the CRJ series is incredibly over-powered.

[Ceemosp]

Launchbury wrote:
What a hunk-o-junk! Even my ancient 727 cruises at Mach .81 and maxes at .86! My advice: Get something that doesn't suck.

Yeah...and with the same fuel you burn for toting 168 paxes around the A330 carries 300+....not to mention the "so beloved" narrow body
spaciousness

Greetz Carsten