flights flying over liverpool

[chris4567]

im in south liverpool (Right by the airport) and see hundreds of flights everyday,with conatrails and without.i know the ones that go from man as there lower than all the others.some come down from scotland,ireland,some from usa canada.is there anymore info possible,where there heading etc.

[chiglet]

Have a look at www.ais.uk.org or try Google Earth and click on airways. Both free, but you have to register with ais :ok:
Simply, depending on the weather systems, aircraft fly the North Atlantic "Northabout" or "Southabout" Imagine a great big whirlpool of air, about 500 miles west of Ireland. If the whirpool is "Clockwise", the traffic will go south because they have a tailwind....if anti-clockwise north. Also there is a lot of traffic to and from Europe-Ireland, both Civil and Military. Hope this helps
watp,iktch

[chris4567]

oh great thanks,a lot dont even seem big and cant all be coming in out of ireland.

[CentreFix25]

Fair bit of traffic departing NCL heading South will pass by, as shown here (http://www.airliners.net/open.file/1189504/L/).

[LN-KGL]

The correct link to chiglet's reply is http://www.ais.org.uk/

[clifftop]

I was going to start a new topic with a question, but it fits in with this subject so here goes:

Why do some contrails "last" longer than others?

I saw 3 'planes at what certainly appeared to be cruising alt, one had a contrail I'd say approx 100 times the length of the aircraft body slowly disappearing as it went.

Another had a trail which must have been many many miles long, I'd guess 50+ miles.

The third had NO contrail at all.

Now I know they could have been immensely different in size: ie 747, A319, Bae746 etc but, they did look at similar alts, so why does that happen???

[Leftexit]

There are a lot of variables in calculating whether contrails will be persistant. If you know the altitude you can use a recent/forecast tephigram for the area to see whether they will be persistant/temporary/or non existant. This thread explains some of the details:- http://www.pprune.org/forums/archive/index.php/t-178738.html

[chiglet]

Contrails...covered elsewhere on this forum, but here goes....
There are two types of "Condensation Trail"...
One is the "visible" exhaust gas at high altitude...
The other is the "Streamer" from the aircraft on landing
Depending on the temperature at the Tropopause, Con-Trails can last a [very] long time....[When I was in the RAF, con-trails were either Persistant.. Long Lasting...or Non-Persistant...Fairly Short. Happens anywhere from 25000 feet up, depending on season. The colder it is, the lower the layer that the 'trails form.
The "Streamer" on landing, is a "Pressure" vortex..Air moves across a wing, and the difference in pressure between the upper and lower surface of the aerofoil [wing shape] can give a trail...especially in damp weather
Hope this helps
watp,iktch