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flyndad
30th Jul 2008, 22:45
Whats the easiest and clearest way to demonstrate this exercise?
Thoughts and views appreciated.

john_tullamarine
30th Jul 2008, 23:22
Fly a steeper than normal approach with sideslip to adjust ? I can't think of anything easier than just do it and there you have it ....

hugh flung_dung
31st Jul 2008, 10:35
I think we have a terminology issue here.

A wing-down approach (or forward slip, being as you don't have the privilege:p of being in the UK) is flown by rolling-out on the normal approach path, then using rudder to align the fuselage with the runway, then using bank to maintain the centre (center:}) line - although naturally variations in rudder/aileron need to be coordinated.
Once the stude can slide all the way down final like this, teach them to transition to it from late in a crabbed approach (prevents the pax from having to be flopped against the sidewall for too long).

A typical difficulty is that people forget that they need to coordinate rudder/aileron once they've got them set-up.

HFD

bartonfly88
31st Jul 2008, 23:58
In Canada its "centre":)

homeguard
1st Aug 2008, 00:23
If the aim is to side-slip to lose excessive height on the approach OK but if not please do not approach with cross controls! Head into into wind to prevent drift (crab) as one would normally do.

If we are talking about the landing then: during the hold off side slip into wind equal to drift. With an angle of bank the aircraft will turn toward the lower wing. Prevent the turn, resulting from an angle of bank, using opposite rudder to keep straight, however, the nose will not be aligned with the runway!

barit1
1st Aug 2008, 01:15
Since drag is high - the fuselage is broadside to the relative wind - it's easy to bleed off airspeed too quickly and find yourself in an incipient stall-spin. Thus you need to hold the nose lower than usual to maintain airspeed.

But with that caveat, slipping to a crosswind landing (or to clear an obstacle) is excellent coordination practice. :)

john_tullamarine
1st Aug 2008, 01:38
do not approach with cross controls! Head into into wind to prevent drift (crab) as one would normally do.

Some thoughts ..

(a) either approach technique is acceptable in a crosswind although the slip approach (rather than crab) is uncomfortable for the passengers and a pain in gusty conditions

(b) during the landing it is general to align to the runway prior to and during the flare and touchdown (albeit that many larger aircraft can tolerate a moderate drift angle at touchdown .. I'm sure we have all watched with wide eyes at Boeing, and other, landing tests)

(c) if the point of the slip is to lose some height quickly the heading can be constrained according to the pilot's control inputs. Generally one would only be aligned with the runway if the aim is to correct for crosswind ... otherwise you will be slipping away from the extended centreline whether you like it or not ?

(d) anytime you are in a steady slip and controlling heading with rudder you have crossed controls

... or have I missed something along the way ?

HonAlgyLacey
1st Aug 2008, 08:06
I find it easiest to teach maintaining the centreline by putting the into wind wing down and then showing the student you simply then line the fuselage up with the runway using rudder.
Teach it initially fairly high on th eapproach and then lead them into a combination crab approach with using the wing down method at the end.
The better they get the lower down they can implement the wing down

Good Luck

Badgeman
10th Aug 2008, 06:23
The way I teach it is like this:

The airplane is a dog. All dogs sniff the wind. While doing your approach to land, the nose of the airplane points into the wind like a dog sniffing it out. Now that you know where the wind is coming from, "point the nose with your toes" (down the runway) and "fight the wind with your fists" so you don't drift across the runway.