747 X-Wind Landing Technique?
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747 X-Wind Landing Technique?
What tips do people have for 747-400 strong X-wind landing technique?
The proximity of the inner pods to the ground worries me (6deg AOB and they hit?).
Am I right in thinking that if you follow the FD's to the runway they will offset you, due to the ILS receiver being in the nose?
Is it OK to land with drift on the dry? (Our flying manual recommends this in wet conditions ... seems a bit agricultural).
At what point do most people kick out the drift?
I don't find when I kick off the drift it generates a lot of associated roll, why is this? (Or maybe I haven't experienced max X-winds).
Do people track up wind of the C/L to err on the safe side?
The proximity of the inner pods to the ground worries me (6deg AOB and they hit?).
Am I right in thinking that if you follow the FD's to the runway they will offset you, due to the ILS receiver being in the nose?
Is it OK to land with drift on the dry? (Our flying manual recommends this in wet conditions ... seems a bit agricultural).
At what point do most people kick out the drift?
I don't find when I kick off the drift it generates a lot of associated roll, why is this? (Or maybe I haven't experienced max X-winds).
Do people track up wind of the C/L to err on the safe side?
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To make an auto land on the center line the antenna for the localizer would have to be between the main gear on the belly, otherwise in a crosswind the landing flare would always be on downwind side of CL after decrabbing. I'm quite sure that is where it is located on B767.
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Localiser (and VOR) antenna is at the top of the fin and glide slope in the radome(capture). On gear down these are switched to Localiser ant in the nose radome and g/s on the nose gear doors (track).
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Can be kicked in the flare but it depends on your company procedures. At Ansett the aircraft were landed with almost all the crab. Its pretty impressive what the big girl can take in the way of sideways momentum!
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side-slip (wing low) limits the max crosswind capability as opposed to crab.
You can get a bit more insight from the Boeing flying technique leaflet off the 'smartcockpit' website.- http://www.smartcockpit.com/pdf/flig...echnique/0012/
You can get a bit more insight from the Boeing flying technique leaflet off the 'smartcockpit' website.- http://www.smartcockpit.com/pdf/flig...echnique/0012/
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The proximity of the inner pods to the ground worries me (6deg AOB and they hit?).
Am I right in thinking that if you follow the FD's to the runway they will offset you, due to the ILS receiver being in the nose?
Is it OK to land with drift on the dry? (Our flying manual recommends this in wet conditions ... seems a bit agricultural).
Land with the airplane tracking straight down the runway, regardless of slip/crab angle. The high inertia of the airplane will tend to keep it tracking in the same direction as the touchdown velocity vector, and it will begin to align itself after the main gear are on the ground.
At what point do most people kick out the drift?
Only with extreme (20+ kt) crosswinds on dry pavement will I "kick out" remaining crab angle. A constant velocity vector is MUCH more important than fuselage alignment with the runway centerline at main gear touchdown.
I don't find when I kick off the drift it generates a lot of associated roll, why is this? (Or maybe I haven't experienced max X-winds).
Do people track up wind of the C/L to err on the safe side?
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In a decent crosswind, you need to line the nose of the aircraft with what appears to be the upwind side of the runway. When you kick out the crab, (I use right at 10 feet), The nose swings right around to the center of the runway. Its kinda wierd, but you have to trust this. Stay in a crab until 10-20 feet off the ground. You will still have to use a little bit of aileron to keep the wings level, but it does work well.
Doing the forward slip/cross control is a bit risky on a 747. You just don't have much bank angle to play with.
Clear as mud??
Doing the forward slip/cross control is a bit risky on a 747. You just don't have much bank angle to play with.
Clear as mud??
Warning Toxic!
Disgusted of Tunbridge
Disgusted of Tunbridge
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I agree with the last 2 posts, stick to using crab, don't touch crossed controls on the 747 unless it is a procedure you are completely happy about. After the 30' call, pause, the gently push drift off(stop using the expression 'kick off drift'- you do nothing of the sort) so you are lined up. Don't hold off for a smooth landing or you will start moving sideways. If you gently push the drift off, only a relatively minor aileron correction will be required, but it may be needed for longer than you expect. Keep the wings exactly level at all times.
On final approach, I do not think you sho uld be following flight director. You should be watching centreline and placing yourself upwind of it, and watching VASIs to make sure you do not go low- or high. Get it wrong at a late stage of the approach and you cannot pull off a good landing, so work really hard to be in the right slot and stay there. Better to be visual if you can than to stay on instruments, then look up suddenly and try and flare by eye. On good weather days, note how at below 400', you have to remove some power to avoid getting high as you enter ground effect. This effect may not be apparent in strong, changeable winds.
Enjoy flying the beast. It is magnificent.
On final approach, I do not think you sho uld be following flight director. You should be watching centreline and placing yourself upwind of it, and watching VASIs to make sure you do not go low- or high. Get it wrong at a late stage of the approach and you cannot pull off a good landing, so work really hard to be in the right slot and stay there. Better to be visual if you can than to stay on instruments, then look up suddenly and try and flare by eye. On good weather days, note how at below 400', you have to remove some power to avoid getting high as you enter ground effect. This effect may not be apparent in strong, changeable winds.
Enjoy flying the beast. It is magnificent.
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Continue to keep aileron/spoiler into wind applied down to 30-40 knots. The wing reacts to crosswind gusts down to those speeds! Due to the degree of sweepback, secondary effects of yaw are marked (see the engine failure case).
Don't forget the outer pods. An outer pod strike will occur with 7 degrees of bank - the outer portion of the wing flexes downwards during landing.
During takeoff, keep rudder corrections smooth and continue to fly the wings level - watch for it coming out of ground effect.
Enjoy!
Don't forget the outer pods. An outer pod strike will occur with 7 degrees of bank - the outer portion of the wing flexes downwards during landing.
During takeoff, keep rudder corrections smooth and continue to fly the wings level - watch for it coming out of ground effect.
Enjoy!
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Note that the 747-400 in Autoland uses a combination of wing-low/top rudder and crab.
I sure wish we could agree on terms here! "Drift" (at least in the US) is what happens when you do NOT apply the appropriate correction (crab or slip)!
I'll stop "kick"ing if you stop "drift"ing!
I sure wish we could agree on terms here! "Drift" (at least in the US) is what happens when you do NOT apply the appropriate correction (crab or slip)!
I'll stop "kick"ing if you stop "drift"ing!
