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two basic questions .

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two basic questions .

Old 30th Sep 2010, 04:57
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two basic questions .

question one :
on FCOM,i see this a lot ."this speed give you FULL MANEUVER ABILITY or AT LEAST 45 DEGREE BANK,25 BANK AND 20 OVERSHOOT.'"

can any body tell me what this full maneuver ability is ?i am pretty sure i have ever learned this definition from my private pilot ground school,but could not remember it now .

question two:what is a foward slip?as long as i can remember now ,i did the foward slip approach on a cessna with right rudder and left york.but it was ten years ago.and as a student pilot i just follow the instructions and didnt think too much....and this morning i was reading this FCTM of 737NG,a chap about rudder trim technic.it says for the correct trimming ,there might be a bit FOWARD SLIP.and a slight bank angle.and also a deflection of the skid indicator.
can the bank angle to either side ?which side should it be ?
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Old 30th Sep 2010, 10:11
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Hi b744FPEK,

Full maneuver capability is the speed for a particular configuration which gives you a stall margin which allows normal bank of 30 degs (+ an overshoot margin). If your speed is less than that figure, then you're restricted to a maximum of 15 degs bank.

Forward slip is a cross wind landing technique, where you fly with some bank into wind and with some "opposite" rudder to align your heading with the runway track.
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Old 30th Sep 2010, 12:02
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thank you .rudderrudderat.
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Old 30th Sep 2010, 12:56
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Full maneuver margin is a speed which allows you to pull a certain amount of G without stalling. In the case of the 737 NG the amber "hockey stick" on the speed tape represents a 0.3 g maneuver margin (i.e. 1.3 g load factor) which is what you would experience in a 40 deg bank level turn. Since you won't deliberatly exceed 30 deg bank in a transport aircraft this provides some allowance for error.

The second part of your question refers to the primary rudder trim technique in the B737 NG FCTM. In general you would trim the rudder in order to eliminate slip and thus minimise drag. However this is a simple trimming technique which may not be perfectly accurate. It could leave you with a slight slip condition, (either way)

If you want greater accuracy of trimming, read the next paragraph about the alternate rudder trim technique.
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Old 30th Sep 2010, 13:35
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rivet gun .
thank you .totally understand now .
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Old 30th Sep 2010, 18:08
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Actually, forward slip is a descent steepening maneuver. Sideslip is a Xwind landing maneuver.

In the words of your FCOM it is correct, the correct rudder trim technique may induce a small FORWARD slip, where the nose of the airplane may not be alligned with the heading.

Slip (aerodynamic) - Wikipedia, the free encyclopedia

Some reading material!
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Old 30th Sep 2010, 19:47
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Sideslip is a Xwind landing maneuve
Sideslip is also (and has been since flight immemorial) a descent steepening maneouvre.. i.e. some degree of crossed controls

Typically (or classically) and maybe most commnly seen and used by stringbags (Tiger Moths etc) to slip into tight fields, uncrossing the controls over the fence
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Old 1st Oct 2010, 02:56
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Actually, forward slip is a descent steepening maneuver. Sideslip is a Xwind landing maneuver

They're both the same other than for the desire, in one case, to track a desired path over the ground (for landing)
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Old 7th Oct 2010, 22:14
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Seems like someone's playing with words rather than actions...
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Old 8th Oct 2010, 16:34
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there is a lot of misunderstanding among the pilots with regards the two types of slips.

A Side Slip is used to correct a crab condition and to line up the aircraft with the runway centerline during a X-wind landing.
You bank into the wind and apply rudder to keep the longitudinal axis of the airplane aligned with the runway centerline.

A forward Slip is to loose altitude if you are high on final. slight bank not more than 5 degrees and apply full rudder in the opposite direction. a perfect forward slip would have the aircraft longitudinal axis NOT aligned with runway extended centerline (or the relative flight path). This will cause the side of the fuselage to meet the relative airflow and cause high parasite drag and hence the loss of altitude.

They both serve a different purpose.
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