USN Photo of the Day: Hello! Jaw-dropping F/A-18F Super Hornet fly-bys! Is this just a dream?

Navy NewsStand - Eye on the Fleet, United States Navy (USN) | November 5, 2006; September 11, 2006 | Jarod Hodge, Unjted States Navy; Joshua Wayne LeGrand, United States Navy

[EnjoyingLife]

Photo 1. An F/A-18F Super Hornet fighter jet assigned to the "Diamondbacks" of Strike Fighter Squadron One Zero Two (VFA-102), Carrier Air Wing Five (CVW-5), USS Kitty Hawk (CV 63), 5 November 2006, Pacific Ocean. Image ID: 061105-N-8591H-389

Photographer
Mass Communication Specialist 3rd Class Jarod Hodge, United States Navy

Links
http://www.Navy.mil/management/photodb/photos/061105-N-8591H-389.jpg (big image)
http://www.Navy.mil/view_single.asp?id=40674 (original source)
http://ChamorroBible.org/gpw/gpw-20061112.htm (above image from this site's fine F/A-18 photo gallery)





Photo 2. An F/A-18F Super Hornet fighter jet assigned to Strike Fighter Squadron One Zero Two (VFA-102), Carrier Air Wing Five (CVW-5), USS Kitty Hawk (CV 63), 11 September 2006, East China Sea. Image ID: 060911-N-8604L-741

Photographer
Mass Communication Specialist Seaman Joshua Wayne LeGrand, United States Navy

Links
http://www.navy.mil/management/photodb/photos/060911-N-8604L-741.jpg (big image)
http://www.navy.mil/view_single.asp?id=39129 (original source)
http://ChamorroBible.org/gpw/gpw-20061112.htm (above image is one of several excellent F/A-18 photos at this URL)

[Tamzee]

Thanks for the amazing videos, wow!!!

[Alice in Wonderland]

You are correct, it was the USS America. I'll let my USAF friend know. Thank you.

"It's not risky at all with practice…it was my opening pass to a Tomcat tactical demonstration at sea. I started from the starboard rear quarter of the ship, at or slightly below flight deck level. Airspeed was at about 250 knots with the wings swept forward. I selected afterburner at about 1/2 mile behind and the aircraft accelerated to about 325-330 knots. As I approached the ship, I rolled into an 85 degree angle of bank and did a 2-3 g turn, finishing about 10- 20 degrees off of the ship's axis. It was a very dramatic and, in my opinion, a very cool way to start a carrier demo. The photo was taken by an Aviation Boson's Mate who worked the flight deck on the USS America. Just as an aside...the individual with his arms behind his back is Admiral Jay Johnson, the immediate past Chief of Naval Operations for the Navy."

[Revolutionary]

I have always referred to it as the shock cone. It occurs just before the aircraft goes supersonic (when the humidity is high enough). It mostly disappears when the aircraft goes through the Mach, although you can still see remnants of it further back on the wing. It is caused by a decrease in pressure behind the forming shock wave. You can get it on the top of the wing (positive Gs)by pulling enough G's to decrease the pressure. The more humid it is the lower the required G's or the more pronounced the effect is at higher G's.

[Gandalf_The_Gray]

It's caused by going supersonic.

That is true of the only some of these pictures. I have seen similar photos of a B2 which is definatly sub-sonic. In that case the airflow over the wing experiances a drop in pressure which causes the same vapor to form.

Of course all airplanes experiance this differential pressure across the wing section. Bernouli's therum dictates that this is how a wing generates lift. I expect the the cloud formation (either sub or supper sonic) has more to do with the degree of saturation of the air. The closer the ambient temperature is to the dew point, the more likely that a pressure difference will form vapor.

Regards,
GtG

PS Prandtl-Glauert singularities generly form at the front tip of the fusilage and along the leading edge of the wing.

[EnjoyingLife]

The B-2 Spirit Stealth bomber (a high subsonic aircraft according to the USAF, but a number isn't specified) and Prandtl-Glauert Clouds:

1. "Clouds on a B2 Bomber" by Virginia Tech's Dr. Mark S. Cramer: http://www.GalleryOfFluidMechanics.com/conden/b2bg.htm -- Via http://www.GalleryOfFluidMechanics.com/conden/pg_sing.htm

2. Beautiful, large high-resolution images of Bobbi Garcia's picture of the B-2 Spirit with the P-G cloud: http://community.Webshots.com/album/64801559Zbdmph -- Via http://www.Wilk4.com/misc/soundbreak.htm and http://www.Wilk4.com/misc/soundbreak.htm#b2

3. And now for the only known public video with a clip showing the B-2 Spirit causing a P-G cloud to appear around the bomber, and it happens very fast: http://www.is.NorthropGrumman.com/videos/b2_tx.wmv -- Via http://ChamorroBible.org/gpw/gpw-20040818.htm (P-G Cloud, 2nd collection; actually all the collection list the video)

This Prandtl-Glauert Singularity thingy is cool, but bizarre.

[VOA]

bump

[ProtectOurFreedom]

LOL. It looked just like #2 by the GG Bridge, except the cloud was much more irregularly shaped.

I read a lot of these links after seeing this thread. One of them said that the clouds form at subsonic speeds in high g turns near the water. The F/A 18 was flying straight and level a few hundred feet over the water when I saw it. Another of the links said the clouds form in high humidity conditions, so the Navy sees quite a few of them.

[EnjoyingLife]

At #19 Moonman62 wrote: Neither one of those photos look right.

Moonman62, what's troubling about the photos?

[EnjoyingLife]

10 September 2005, Freedom Through Friendship Air Show, Osan Air Base, Korea: United States Marine Corps (USMC) F/A-18C Hornet jet fighter assigned to the Strike Fighter Squadron One Nine Five (VFA-195) at Naval Air Station Atsugi, Japan. Image ID: DFSD0602979, 050910-F-4707M-142

Photographer
Tech. Sgt. Raheem Moore, United States Air Force, http://www.af.mil

Links
http://www.dodmedia.osd.mil/Assets/2006/Air_Force/DF-SD-06-02979.JPEG (big image)
http://www.dodmedia.osd.mil/DefenseLINK_Search/Still_Details.cfm?SDAN=DFSD0602979&JPGPath=/Assets/2006/Air_Force/DF-SD-06-02979.JPG (source)
http://ChamorroBible.org/gpw/gpw-20061112.htm (above smaller image -- #8, ALT text)

[FastCoyote]

it's moisture in the air that is knocked into a mist by the shock wave.

[EnjoyingLife]

Ladies and Gentlemen of FreeRepublic.com, Distinguished Visitors!

For your viewing pleasure here are two fine video clips of the U.S. military's F-18 Hornet in various "tutu" outfits (see post/comment #15 for background on the tutu designation), i.e., the F-18 fighter jet is transonic and massaging the Prandtl-Glauert singularity resulting in a Prandtl-Glauert Cloud.


1. 2005 Chicago Air Show: http://video.google.com/videoplay?docid=-4785175348178531287

2. http://home.pacbell.net/ok3/f-18flyby.mpg

[VOA]

thanks for all the great photos!

Here's a bump for publicity for the Sunday crowd

[EnjoyingLife]

A post in Slashdot's discussion regarding the Prandtl-Glauert Condensation Cloud phenomena ("The Beauty of Fluid Mechanics in Video and Photos", 20 November 2006, http://science.slashdot.org/article.pl?sid=06/11/20/1456204) brought up questions that frankly I hadn't considered before. Any thoughts on the matter?

"From a tactical standpoint isn't it a major downside in air-to-air combat to have that giant cloud behind you? Wouldn't that completely block your rear view? Also, wouldn't it increase the aircraft's visual profile? What does this do to its radar profile?" Posted by Lord_Dweomer on Monday, November 20, 2006 at 01:53PM, #16918484, http://science.slashdot.org/comments.pl?sid=207510&cid=16918484

[Fresh Wind]

They save space by stacking them on their wingtips.

[Redcitizen]

That needs a caption: Look Ma, No hands!

[SunTzuWu]

here ya go....a f-14 breaking the barrier between two navy ships

Very cool clip. I've seen this before on YouTube but the resolution is much better on the link you provided. Has anybody noticed that the F-14 kicks out about six flares just before he passes the carrier?

[raygun]

cool thread

[EnjoyingLife]

WOW! shot of a transonic U.S. Navy Blue Angels F-18 Hornet fighter jet's realy low-level pass. I've seen a similiar photo of a Blue Angels F-18 doing this over water, but over land.

Photo Link: http://www.fencecheck.com/forums/index.php?action=dlattach;topic=4587.0;attach=143631
Photographer: "Angie"
Date and Location: 10 November 2006, Blue Angels Homecoming Air Show 2006, Naval Air Station (NAS) Pensacola, Florida
Post link: http://www.fencecheck.com/forums/index.php/topic,4587.msg115616.html#msg115616 ("Reply #125 on: November 27, 2006, 12:41:47 PM")

[shekkian]

keewwwwlllll

[2111USMC]

I shudder every time I see that pic!