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Guest hvanleusen

Manual Approach 2

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Guest HPSOV

Different airline different policy....Where I fly we use a completely different system known as reference ground speed (RGS).To determine reference ground speed you take Vref and subtract the base headwind component, add a knot for every 5 degrees above ISA, and for every 1000ft pressure altitude.For the approach you now have 2 minimum speeds, the first being Vref+5, and the second being RGS. You take the HIGHER of these two to be the minimum speed you fly (remembering that RGS relative to IAS will change as the wind changes on approach).The maximum speed for an approach is Vref+20. If you are flying at Vref+20, and are still below RGS, then the windshear is too great and you shouldn't be landing!As a side note the Vref+20 is given as the maximum speed because at this speed your attitude will be about 1 degree nose down, any faster and the nose wheel will hit before the mains."Passing the threshold the speed should have been reduced to Vref"Fly your minimum speed (Vref+5/RGS) right into the flare.

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Martin is correct - on both counts.The Boeing procedure is to add half of the headwind component plus all of the gust for a minimum of Vref(30)+5 to a maximum of Vref(30)+20. We carry the wind additive until the flare and the gust to touchdown - but never below Vref(30)+5. But remember it's only on the headwind component. You can have a steady 25 knot crosswind and still fly Vref(30)+5.If you use the autothrottle all the way to touchdown, it's Vref(30)+5 all the way.As for the speedbrakes, it's shift+/ to arm the autospeedbrakes. This dumps most of the lift on touchdown solidly planting the gear on the ground and giving more braking action/traction - for the same reason they put spoilers on cars.

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Guest hvanleusen

Hmm...., I should have known that speedbreaks are forbidden on short final ..arg... . Interesting question though:Are speedbrakes never allowed to be used when flaps are extended???? Here is a statement of HPSOV from the old Forum concerning descent (hope I

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There is no specific Boeing limitation on the use of speedbrakes with flaps extended.In the flight crew training manual, however, Boeing recommends as follows:"To avoid buffeting, use of speedbrakes with flaps greater than 5 should be avoided. If circumstances dictate the use of speedbrakes with flaps extended, high sink rates during final approach should be avoided. Speedbrakes should be retracted before reaching 1,000 feet AGL."The SPEED BRAKES EXT EICAS message and SPEED BRAKES light along with the beeper appear when the speedbrakes are extended when the flaps are in the landing position, or when radio altitude is 800 feet or below.Most airlines make it a limitation - no speedbrakes with flaps set at more than 5. It really does buffet!!Cheers

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Guest Martin

I've actually read about the RGS or "Minimum GS in Approach" procedure you're describing, but I didn't give it much thought until now.Just making sure I understand this correctly: Does RGS only affect the the minimum speed you are going to fly? Do you still use the normal procedure, adding a few knots for headwind, to obtain VAPP?Example :-):Rwy 30, wind 300 at 20 gusting to 25, OAT 20

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