Time to start rolling after the T/O clearance
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Here we use radar separation on departure (except behind an A380) and a Medium would be 5 miles behind a Heavy at the time the Medium becomes airborne. A wake turbulence cautionary shall also be issued.
Take-off clearance to the Medium in light winds would probably be issued when the Heavy is 4 miles away from the threshold or about 70 seconds after rotation of the Heavy. In stronger winds it takes longer to achieve the spacing, so it would be nearer the ICAO 2 minute standard to achieve the 5 miles.
If you need more than 5 miles (i.e. 2 minutes) please inform ATC before you accept the line-up clearance.
Take-off clearance to the Medium in light winds would probably be issued when the Heavy is 4 miles away from the threshold or about 70 seconds after rotation of the Heavy. In stronger winds it takes longer to achieve the spacing, so it would be nearer the ICAO 2 minute standard to achieve the 5 miles.
If you need more than 5 miles (i.e. 2 minutes) please inform ATC before you accept the line-up clearance.
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Cough,
dependant upon the departure aircraft, we allow about 45 seconds from take off clearance to rotation (and earlier, by wheels up i meant weight off). Often, in "normal" wind conditions this coincides with the point at which the preceding departure is about 2.25nm from the upwind end of the runways as marked on our ATM (radar screen) - this gives an alternate guide
Ultimately, pilots can take more, but very rarely is it requested. TBF, the majority of EGLL departures are great and keen to help out. But sods law dictates that the one that really needs to get a shift on is the ditherer! In any case, if I require a prompt departure, I normally check and prewarn pilots. If their response is anything less than a resounding
, then it's not going to happen. And remember, we may want you to expedite in order to depart another aircraft after you, before the next inbound lands. Frustrating when for want of a few seconds, a gap is "wasted"
dependant upon the departure aircraft, we allow about 45 seconds from take off clearance to rotation (and earlier, by wheels up i meant weight off). Often, in "normal" wind conditions this coincides with the point at which the preceding departure is about 2.25nm from the upwind end of the runways as marked on our ATM (radar screen) - this gives an alternate guide
Ultimately, pilots can take more, but very rarely is it requested. TBF, the majority of EGLL departures are great and keen to help out. But sods law dictates that the one that really needs to get a shift on is the ditherer! In any case, if I require a prompt departure, I normally check and prewarn pilots. If their response is anything less than a resounding
, then it's not going to happen. And remember, we may want you to expedite in order to depart another aircraft after you, before the next inbound lands. Frustrating when for want of a few seconds, a gap is "wasted"
Last edited by hold at SATAN; 3rd Mar 2013 at 21:23.
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...or as The Infamous Mr. C. at Heathrow would say back in the old days - "Come rahnd the corner, power up against the brakes...and go when I tell yer..."
(HD might like that one...)
(HD might like that one...)
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"Come rahnd the corner, power up against the brakes...and go when I tell yer..."
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Thanks Satan!
On the PIK one we waited till 1m15 (so rolled at the standard time) about 1:45 airborne after the heavy (not the best I admit!). Hence my question, do you adjust for destination? 45s does seem to work for most of our routes though.
There is of course a flip side to this, the takeoff time for our longer range destinations could of course go a little the other way...A 321 with destination timbuktoo takes a longer time so you could think about issuing the clearance slightly earlier (tin moving etc!).
As for hanging around routinely - Nahh, no way! And winding up when things are tight - some of us do that anyway (particularly prior to 7am...)
On the PIK one we waited till 1m15 (so rolled at the standard time) about 1:45 airborne after the heavy (not the best I admit!). Hence my question, do you adjust for destination? 45s does seem to work for most of our routes though.
There is of course a flip side to this, the takeoff time for our longer range destinations could of course go a little the other way...A 321 with destination timbuktoo takes a longer time so you could think about issuing the clearance slightly earlier (tin moving etc!).
As for hanging around routinely - Nahh, no way! And winding up when things are tight - some of us do that anyway (particularly prior to 7am...)
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Cough,
we tend not to take destinations into account for medium aircraft. Usually the heavies going to KLAX or RJAA etc will be considered with regards to how quickly they are likely to roll with arriving traffic, or more likely, whether or not to offer intersections for departure. Conversely, some heavies, such as 747 cargo aircraft going to EHAM or LIML will rotate early and climb quickly, in such case it could have an effect on departure (route), as opposed to wake turbulence, separation.
we tend not to take destinations into account for medium aircraft. Usually the heavies going to KLAX or RJAA etc will be considered with regards to how quickly they are likely to roll with arriving traffic, or more likely, whether or not to offer intersections for departure. Conversely, some heavies, such as 747 cargo aircraft going to EHAM or LIML will rotate early and climb quickly, in such case it could have an effect on departure (route), as opposed to wake turbulence, separation.
Last edited by hold at SATAN; 4th Mar 2013 at 15:40.
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Back in the days of Pontius, an aircraft of a large, British airline lined up at Chicago. When cleared for take-off the pilot said "We'd just like to wait a little longer". The lady in the tower replied: "Just shift your ass; landing traffic", which he promptly did!
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Just to clarify a point, once the aircraft has rotated, I.e. nose wheel lifts then vortices are produced from that time therefore time based vortex separation is provided from that point. "Gear up" has no relevance to departure separation, besides we want the gear up ASAP to be clean, it's like having an ex girlfriend hanging on your arm, get rid.
