Vapor cone behind Blue Angel in San Francisco shot at 120FPS

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DifficultCourt1525@reddit

Anyone have an estimated speed? I always thought those clouds formed as they approached Mach 1 but that F 18 appears to be going relatively slow.

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fighterpilot248@reddit

This is hella dope.

Going down to Pensacola for their last show of the season in November and absolutely cannot wait. This gets me so hyped.

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fighterpilot248@reddit

Nov 1st and 2nd.

Looking at the schedule, apparently it isn't their last show, but they are also having the thunderbirds joining in that weekend so should be one amazing show

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danit0ba94@reddit

Well fuck a duck. I wish I knew that magnificent duet would be happening sooner.
Looking forward to seeing the videos.

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zevonyumaxray@reddit

That disturbance on the water surface that is trailing along is something I don't think I've seen before. Cool.

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solateor@reddit (OP)

From OP

Honestly had no idea what a vapor cone was until I saw it in person yesterday. Pretty cool.

A vapor cone (also known as a Mach diamond, shock collar, or shock egg) is a visible cloud of condensed water that can sometimes form around an object moving at high speed through moist air, such as an aircraft flying at transonic speeds. When the localized air pressure around the object drops, so does the air temperature. If the temperature drops below the saturation temperature, a cloud forms.

#sanfrancisco #blueangels #vaporcone #navy

Video:@derick.daily

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From the comments:

Commenter: How do you make them go slow when they’re going so fast 🙌

OP: shot it 120 FPS, makes it appear slow and keeps it smooth!

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My_useless_alt@reddit

Minor correction: A vapour cone is not a shock diamond, a shock diamond is a different thing.

A Mach Diamond (aka a Shock diamond) forms when the exhaust coming out of an engine (Usually a rocket but sometimes a jet) is lower pressure than the ambient temperature, causing it to get compressed inwards, where it is dramatically heated and becomes much brighter, before sorting of bouncing off itself and expanding out again, just for the cycle to repeat. The bright part is the Mach Diamond. The under-engine cam for Space Shuttle launches show the first one rather well, as Shuttle had engines with an especially low exit pressure.

They're more often seen on rockets because the way rockets work it's more efficient to have lower pressure exhaust (Actually it's best if the pressure matches the ambient, but because rockets spend most their time in space it's best to make the pressure as low as possible without breaking the nozzle) and because there's more particulates to light up (Though if there's too many e.g. M1D, F1, basically anything kerosene, Raptor-2 when the engine is itself on fire, etc it'll block the view), though I have seen them in afterburners as well.

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ViciousNakedMoleRat@reddit

Right, the SpaceX Super Heavy produces probably the largest mach diamonds, as you can see in this picture from the launch two days ago.

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rsta223@reddit

Here is a much larger shock diamond than your picture:

https://www.spaceline.org/spacelineorg/wp-content/uploads/2020/10/word-image-142.jpeg

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danit0ba94@reddit

...ok... A short story has to be told here...

I first clicked on his image... And only upon seeing it did I realize Starship was sending one big ol' mach diamond down from the combined thrust of all those raptors. Needless to say I was absolutely shocked how big that thing was.

Then i see your comment... "Here is a much larger shock diamond than your picture."
And i wont lie; i got a bit nervous. I thought to myself "that is the starship! What could produce a mach diamond bigger than that?!?!"

And then i clicked your picture....

As if sensing my nervousness, my phone took forever to load that image. Slowly the Saturn V loaded into view... And it occurred to me that she is taking up a very tiny portion of the whole photo. That made me even more nervous...

And then the thrust plume started loading... And loading... And loading... And loading... And loading...

And then it finally finished loading that entire colossal fucking thrust plume... And my lower jaw unhinged from the rest of my skull...

It's probably a little easier for them to happen that high in the atmosphere, but oh my stars and garters that is such a gigantic Mach fvcking Diamond that... I hardly even have the words for it.

Ok. Storytime over. I'm going to go sit down for a little while.

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rsta223@reddit

Yeah, it's pretty nuts. You can see the same effect in video form here:

https://youtu.be/GllmG7aZHb4?t=356&feature=shared

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ViciousNakedMoleRat@reddit

Haha, yes that is larger, but also a lot more messy. The Super Heavy exhaust is pretty sexy and the mach diamonds do form a nice little chain.

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Tacitblue1973@reddit

Those transonic shocks giving the Bay a good slap on the way past.

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MissionHairyPosition@reddit

Never gets old counting the number of car alarms when they fly over the city proper. It's always the "sneaky" plane that sets them off.

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mencival@reddit

Can’t believe military is now so blatant in dispersing chem trails /s

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te_anau@reddit

so how was this shot?

handheld landscape / 4k+? then cropped and stabilized in post?

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CarbonDudeoxide@reddit

He mentions in his Instagram comments that it was handheld. My pet is iPhone 16 Pro, vertical video, 4K 120 fps

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EnergiaBuran@reddit

Are you SURE that's not a sonic boom?

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DenebianSlimeMolds@reddit

I thought it a good question, but my five seconds of chatgpt tells me that when supersonic there would probably be no vaporcone, something like

vaporcone => low pressure condensation of water
supersonic => high pressure shockwave

I don't think that's the whole story though, the plane isn't just creating low pressure one moment then high pressure the next, so I think chatgpt has given an incomplete explanation

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EnergiaBuran@reddit

Haha, I was sort of channeling Chris Combs and making a joke.

I don't know if I'd rely on ChatGPT to make this determination for me, either.

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DenebianSlimeMolds@reddit

chatgpt is always a hit or miss, but my understanding of it is such that in this circumstance it should be pretty good since I am not asking it to synthesize anything, just asking it to summarize the consensus of thousands of papers and blog posts written on the subject

I do find it handy for this and in ways I can no longer rely on wiki because my experience with wiki is that overtime, it is written by phd wannabes for phds and becomes less and less understandable by laymen.

fwiw, I asked claude (anthropic) and it agreed with chatgpt and explained as follows:

When an F-18 or any aircraft transitions from subsonic to supersonic speed (breaking the sound barrier), there are some interesting changes in the vapor cone phenomenon:

Disappearance of the vapor cone: As the aircraft breaks through the sound barrier, the vapor cone (also known as a shock collar or shock egg) that was visible at transonic speeds typically disappears. This is because the shock wave pattern changes as the aircraft goes fully supersonic.

Formation of shock waves: Instead of a vapor cone, you would observe shock waves emanating from various parts of the aircraft. These shock waves form a cone shape behind the aircraft, often referred to as a Mach cone.

Sonic boom: At the moment the aircraft breaks the sound barrier, an observer on the ground would hear a sonic boom. This is caused by the merging of the pressure waves created by the aircraft's movement.

Potential for multiple shock waves: In supersonic flight, you might observe multiple shock waves forming at different points on the aircraft where airflow changes occur abruptly, such as the nose, wings, and tail.

Change in visual effects: While the vapor cone disappears, you might still see some condensation effects, particularly around areas of low pressure on the aircraft, but these would be less pronounced and have a different shape compared to the subsonic vapor cone.

It's worth noting that the exact transition can be difficult to observe visually in real-time due to the high speeds involved. The changes happen very quickly as the aircraft accelerates through the transonic region (Mach 0.8 to Mach 1.2) into supersonic flight.

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EnergiaBuran@reddit

Regardless, you're still asking ChatGPT to essentially guess, as the AI is not properly suited to evaluate media.

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danit0ba94@reddit

No You Dont!!!

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rsta223@reddit

Honestly, that probably is a sonic boom. They were likely sitting right about at mach 1 or maybe barely supersonic here.

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EnergiaBuran@reddit

In reality it's actually not unless you can provide proof that a sonic boom did indeed occur. It's definitely not supersonic

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SevenandForty@reddit

They weren't supersonic I'm pretty sure; there was no sonic boom when they did the fast pass when I was there on Friday, at least. You can hear the jet a bit before it approaches in this video too, which I don't believe would occur with a supersonic flyby (which you can see/hear an example of here)

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Superman246o1@reddit

I got green smoke. I GOT GREEN SMOKE!

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Rgoven@reddit

The blue angels are artists

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MrOatButtBottom@reddit

We do this shit for fun. Fuck with us, I dare you I double dog dare you

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chucchinchilla@reddit

A friend of mine was on one of those sailboats and filmed the jet flying directly overhead. Absolutely insane.

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danit0ba94@reddit

Im a masochist when it comes to how close im willing to be passed by a plane.
Like, I have no qualms about it being straight up hazardous to my health with how close a pass I'm willing to tolerate.

But having an f-18 rip over my head at speeds like that... Especially if they hit the burners... Even to me, a hard buzz like that seems like just misery and agony to experience.

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slakisdotcom@reddit

You should share the video.

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Character_Ad_7798@reddit

Do the boats have to out of a certain area?

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redrockcountry2112@reddit

Wow

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KualaLJ@reddit

Thank you for not saying it’s the sound barrier!

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rsta223@reddit

This one actually likely is. Not all of the vapor you see around fighters is, but this one's very likely traveling right at or slightly above mach 1, and you're seeing the condensation behind the shock (and you can also see where the shock hits the water below the plane).

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Nice work, OP!

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DrunkenDude123@reddit

The view that last boat got must’ve been crazy. Rip their ears

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sloppyrock@reddit

The opposite of /r/killthecameraman

Nice work!

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