(no subject)

[den]

Comments

[dewhitton.livejournal.com]

You can see the exhaust trail forming in a 747 if you go to the last window and look back. I could see the first fingers of condensation around the outside of the stream chasing the plane.

[acelightning.livejournal.com]

[kelloggs2066.livejournal.com]

I recall seeing a lot of paintings of the contrails coming off the engines of B-17s. There are undoubtedly wingtip vortex created contrails, but they're much smaller than the engine particle created contrails. I would guess that the atmospheric conditions which allow them to form is probably farther from the norm than the engine contrails.

Scott (Not a meteorologist) Kellogg

[level-head.livejournal.com]

If you see pictures of aircraft at altitude -- and we have a number of military aircraft pictures floating around now due to recent activity -- you can see that these are indeed exhaust-triggered rather than wake vortices.

As a general rule, the faster the aircraft is flying, the less severe the wing vortices are. The FAA is only really concerned about them when the heavy aircraft are low and slow, briefly after takeoff and for some time on final approach.

There is always some tip votice activity -- you may have seen a number of recent aircraft with "winglets" on the ends of the wings to squeeze a bit more out of this wasted energy -- but it is less dramatic, has a slower rotational speed, and stays around for a shorter period of time at cruise altitude.

It is possible to get "squeeze clouds" at altitude, but the conditions that support it are much more rare. Contrails, however, are very common.

===|==============/ Level Head