“Jets & Clouds” Effects   1 comment

Fluid dynamics, turbulence, refraction combine to create spectacular sky shows!

More and more high-altitude vapour trails appear in our skies as the flight density of commercial aviation increases. These trails often follow the plane straight and narrow, then degrade into fuzzy and fanciful formations, blending with clouds and leaving a subtle afterimage in our subconscious. We almost do not notice them any more! But as the following photos show, sometimes a simple condensation trail from a jet engine can be worth a second glance.

(images via 12)

(image credit: Bailey, AirTeamImages)

(images credit: Laurent Malbecq2)

Contrails tell the story: here USAF F-15 Eagle Fighters intercept two Soviet MiG-29 fighters:

(image credit: Staff Sgt. Kevin L. Bishop, USAF)

(images credit: TriplETBrett B. Despain)

Tupolev Tu-154 soaring over Siberia:

(images credit: TriplET)

The amazing cloud “downwash effect” forms around a passing Cessna airplane… The sunset light makes it all the more spectacular:

(images credit: Paul Bowen, Cessna Aircraft Company)

Wake turbulence and some interesting fluid dynamics produce intricate baroque-shaped swirls in the clouds:

(images credit: Daniel KouryPaul Bowen)

Here is a truly smooth, fluid and elusive creation:

(image via)

Condensation wingtip vortices give an out-of-this-world quality to this picture:

(image credit: Tim de Groot)

Great show of the wingtip vortices and the wake turbulence effect on the cloud, caused by Airbus A340 approach:

(image credit: Fabricio Jiménez)

Somewhat ominous and ghostly wake turbulence behind a Boeing 747:

(image credit: Daniel Alaerts)

(image credit: Barry McGrath)

(original unknown)

Partial solar eclipse and an aircraft’s vapour trail over Frankfurt:

(image credit: EPA)

Here is a red contrail over… what looks to be a looming Death Star:

(image credit: Stefan Seip)

(image credit: Strange Vehicles)

A big feather in the sky, and some beautiful patterns “enhancing” the sunset:

(images via 123)

(image via)

Propeller vortices could be just as interesting visually as wingtip vortices, but they’re harder to spot and rare to occur: in this case they are clearly seen around the Lockheed Martin C-130J-30 Hercules C4:

(image credit: Sven De Bevere)

Breaking the Sound Barrier: Transonic Cloud Effects

Going over the sound barrier leads to one of the most amazing condensation effects: so called “Prandtl-Glauert Condensation Clouds” caused by the rapid cooling of the air. You have to be really quick with your camera to capture it, as it only occurs at the exact moment of crossing the sonic barrier. This page has many photographs and videos of this phenomena.

A F/A-18F Super Hornet streaks past the aircraft carrier U.S.S. Kitty Hawk in the Philippine Sea:

(U.S. Navy photo by Petty Officer 3rd Class Jonathan Chandler, via)

Skilled pilots can actually control the exact position where such a cloud can appear: “it is possible to work the plane’s throttle (controlling the airspeed) to move the shock wave forward or aft” –

(images credit: Ensign John Gay, U.S. Navy)

As you can see on the left image above, the smaller shock wave appears over the cabin, as well… Here is an F-14 causing the effect, as it completes a super-sonic flyby (left) and F-22 Raptor on the right:

(images credit: Jarod Hodge, Ronald Dejarnett, U.S. Navy)

Our reader Ian Woolard comments on this effect: “These weird clouds occur when the aircraft is moving at transonic speed – these are from about Mach 0.8 to Mach 1.2, and I suspect that none of these aircraft are actually going faster than Mach 1.0. There is a reason for this: the shapes are caused where the air is “temporarily” forced to speed up past the aircraft to supersonic speeds, but since the aircraft is moving below the speed of sound, no sonic boom reaches the ground.”

You can clearly see wingtip vortices in this picture, as the VFA-94 (Fixed Wing Strike Fighter Squadron 94, also known as the “Mighty Shrikes”) F/A-18C Hornets streak across the sky:

(images credit: Mate 3rd Class Elizabeth Thompson, Mate 3rd Class Kristi J. Earl, U.S. Navy)

This shot of rainbow contrails from Airbus A-340 has an ephemeral, almost surreal quality:

(image credit: Jeff Well)

 man-made rainbows in the sky:

(image credit: Karol Staniec)

And finally, here is a striking fiery contrail from a 747, fading in the last rays of the setting sun:

(image credit: Ivan Voukadinov)

Posted July 9, 2013 by kitokinimi in Uncategorized

Tagged with , ,

One response to ““Jets & Clouds” Effects

Subscribe to comments with RSS.

  1. Very nice.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: