"Andy Breen" wrote in message
On Thu, 03 Nov 2011 21:50:23 +0000, Graeme Wall wrote:
On 03/11/2011 21:08, Recliner wrote:
"Graeme wrote in message
On 03/11/2011 09:46, Mike Bristow wrote:
In
article4c96e498-1358-4e79-a673-
,
wrote:
What's not to like? :-)
The fact that it's east of London. Given that the prevailing
winds are east/west, it seems silly to put an airport to the east
(or west) of London, rather than North or South - it means that
the noise will impact more people.
Prevailing winds are actually westerly hence the claim that the
airport can operate 24/7 because the approach will be mainly over
the North Sea. What they've omitted to mention is that
departures will be straight over London.
Not a problem -- planes can turn sharply within a couple of miles of
take-off. They hardly ever stay straight all the way up to
altitude. So none need fly over central London.
They've still got to feed in to the different airways. some of which
will still take them over London.
And the more wiggling about they do, the more fuel they will have to
burn - particularly if they have to do it just after take-off, when
they're heavy with fuel. That's got immediate environmental costs,
will add to operating costs and could make the airport unattractive
for airlines operating the very long-haul routes (Japan, Australia..).
You also really don't want to be manoevering at maximum weight and
have an engine ingest a goose. That could lead to substantial stress
in the cockpit.
Regardless of what's on the ground, they routinely start to turn very
soon after take-off, so as to head in the direction they need to fly
(ie, to join the airway). It's not normally straight ahead. Also, planes
take off much more steeply than the landing glide slope, so they quickly
reach an altitude high enough that noise isn't a problem. Heavy
four-engined planes do take off at a shallower angle than twins, but
it's still much steeper than the 3 degree glide slope.
I'm off to Shanghai tomorrow, and I very much doubt that we'll fly over
central London, even if the take-off is from 09R (they don't normally
use 09L for take-offs, as that would route flights at low altitude over
populated areas).