Aeronautical Insanity: switching to secondary tolerances

The Something Awful Forums > Discussion > Automotive Insanity > Aeronautical Insanity: switching to secondary tolerances

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Bondematt: Jan 26, 2007; Not too stupid

coldpudding posted:

How bad would it be if you flew into one of those balloons?

When I was a little kid I thought of an anti airship device that was just a long steel cable you would let reel out the back of a plane, it wasn't till I was older that realized that ww1 planes could not fly that high

Pretty bad! One thing you don't get here is the sense of scale, that thing was huge.

Funny enough, barrage balloons are basically the opposite of that.

# ? Feb 7, 2023 08:43

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# ? May 25, 2024 02:32

Luigi Thirty: Apr 30, 2006; Emergency confection port.

London in WW1 had an aerial equivalent of anti-submarine nets, strung between barrage balloons. Not so much to crash into, but to make it too hazardous to bomb specific areas since you�d have to fly above the balloons, making your enormous bomber sputtering through the air at 80 knots an even easier target for the ack-ack guns.

# ? Feb 7, 2023 09:29

Humphreys: Jan 26, 2013; We conceived a way to use my mother as a porn mule

Have they released photos of the wreckage and what it was carrying?

# ? Feb 7, 2023 09:43

Hadlock: Nov 9, 2004

PittTheElder posted:

Which is pretty astonishing given how much helium that would have taken. That balloon was loving expensive, before it even had a payload attached. For a high altitude unmanned balloon I'd really think hydrogen would be the play.

Wild rear end guess, but because helium is ~twice as large as helium, it leaks through the latex envelope a lot slower than hydrogen

Although at ~100,000 ft the pressure delta between inside the balloon and outside is probably negligible compared to when it first is inflated at sea level

Those balloons look super wonky on the ground, you get the physics dialed way up and it looks like a giant bubble under a sheet, shaped more like you'd expect to see a bubble in a pint of beer

# ? Feb 7, 2023 10:20

shame on an IGA: Apr 8, 2005

Bondematt posted:

Pretty bad! One thing you don't get here is the sense of scale, that thing was huge.

Funny enough, barrage balloons are basically the opposite of that.

yeah DoD cited a 200' diameter in the last briefing, this is roughly to scale:

# ? Feb 7, 2023 12:33

Platystemon: Feb 13, 2012; BREADS

Mr. Musk, please fly a rocket through the next one, for science.

# ? Feb 7, 2023 12:37

Humphreys: Jan 26, 2013; We conceived a way to use my mother as a porn mule

Just saw pics of the wreckage of the 737 in WA. Amazing how the crew survived that.

# ? Feb 7, 2023 13:08

Cable Guy: Jul 18, 2005; I don't expect any trouble, but we'll be handing these out later...; Slippery Tilde

Humphreys posted:

Just saw pics of the wreckage of the 737 in WA. Amazing how the crew survived that.

Jesus... they walked into the hospital 'unscathed' after being transported there.

loving miracle.

Cable Guy fucked around with this message at 13:41 on Feb 7, 2023

# ? Feb 7, 2023 13:37

Vincent Van Goatse: Nov 8, 2006; Enjoy every sandwich.; Smellrose

Platystemon posted:

Mr. Musk, please fly a rocket through the next one, for science.

*Rocket bounces off the balloon and hits Boca Chica, Looney Tunes style*

# ? Feb 7, 2023 13:47

Serjeant Buzfuz: Dec 5, 2009

Cable Guy posted:

Jesus... they walked into the hospital 'unscathed' after being transported there.

loving miracle.

Any landing you walk away from...... Right??

e: I keep imagining that scene from ST Generations where the Enterprise saucer crashes into the ground.

# ? Feb 7, 2023 14:13

slidebite: Nov 6, 2005; Good egg

Cojawfee posted:

Canada tried to shoot down their own balloon a few years ago and bullets didn't do much if at all to it. Shooting a missile and causing an explosion is the easiest way to ensure a big hole gets ripped in the balloon and it falls.

You're talking about the one that ended up going across the Atlantic and finally ended in Russia or Finland?

https://www.cbc.ca/news/politics/weather-balloon-canada-china-1.6737831

Both the Canadian and the Royal Airforces failed to take it down with rounds.

# ? Feb 7, 2023 15:27

coldpudding: May 14, 2009; FORUM GHOST

Hey wait a min hasn't the US been spending billions of dollars on airborne lasers? Slicing up a big balloon sounds like an ideal test case for such a thing.

# ? Feb 7, 2023 15:51

`Nemesis: Dec 30, 2000; railroad graffiti

Humphreys posted:

Have they released photos of the wreckage and what it was carrying?

landed in the ocean but they know exactly where and you can bet your rear end they will be salvaging the debris.

# ? Feb 7, 2023 17:01

Nebakenezzer: Sep 13, 2005; The Mote in God's Eye

slidebite posted:

You're talking about the one that ended up going across the Atlantic and finally ended in Russia or Finland?

https://www.cbc.ca/news/politics/weather-balloon-canada-china-1.6737831

Both the Canadian and the Royal Airforces failed to take it down with rounds.

Thanks for posting this; people have been referring to this for awhile, but it's nice to read the facts.

Sidebar: I am a little confused as to why being shot with a 20mm cannon was so ineffective. Because you don't slash it with fire, it just pokes two 20mm holes in the balloon, and it turns out that's a slow leak? I do get that they give the balloon so much gas, and that expands as altitude increases. Is the gas in the balloon in equilibrium with air pressure once max altitude is reached?

# ? Feb 7, 2023 17:20

Sagebrush: Feb 26, 2012

It's a very, very small overpressure. Like less than 1000 Pa, or about 1% more than atmospheric pressure. Comparable to inflating your car's tire to a reading of 0.15 psi.

# ? Feb 7, 2023 17:24

slidebite: Nov 6, 2005; Good egg

As the helium leaks out the balloon it will descend into higher air pressure and the holes will shrink.

Think of stretching a balloon or sheet of rubber. Then poke holes in it while stretched.

Then let go of it. The holes get smaller. That's in essence what's happening as the balloon descends.

Remember, at altitude this thing is *massive* - as in high-rise apartment building massive. A bunch of bullet holes, even 20mm, is gently caress all. It's less than mosquito bites on a elephant.

# ? Feb 7, 2023 17:52

Wombot: Sep 11, 2001

Humphreys posted:

Have they released photos of the wreckage and what it was carrying?

Some preliminary photos, mostly of the envelope.

shame on an IGA posted:

Navy PAO released some close-ups of the balloon recovery, looks like it was made out of pallet wrap and stage lighting truss

https://www.dvidshub.net/image/7620705/high-altitude-balloon-2023

# ? Feb 7, 2023 18:14

BIG HEADLINE: Jun 13, 2006; "Stand back, Ottawan ruffian, or face my lumens!"

I'd take back (almost) everything negative I've ever said about China if, on most of the sensitive stuff was stamped "~~Made in~~ Stolen from the USA."

BIG HEADLINE fucked around with this message at 19:46 on Feb 7, 2023

# ? Feb 7, 2023 19:44

Beef Of Ages: Jan 11, 2003; Your dumb is leaking.

BIG HEADLINE posted:

I'd take back (almost) everything negative I've ever said about China if, on most of the sensitive stuff was stamped "~~Made in~~ Stolen from the USA."

All the time I've spent in China over the years (pre-pandemic) does not suggest that Chinese bureaucracy lends itself to intentional humor.

# ? Feb 7, 2023 20:18

BIG HEADLINE: Jun 13, 2006; "Stand back, Ottawan ruffian, or face my lumens!"

Beef Of Ages posted:

All the time I've spent in China over the years (pre-pandemic) does not suggest that Chinese bureaucracy lends itself to intentional humor.

I know, but it's funny to imagine.

# ? Feb 7, 2023 20:19

Beef Of Ages: Jan 11, 2003; Your dumb is leaking.

BIG HEADLINE posted:

I know, but it's funny to imagine.

For sure. The unintentional stuff is good, too. Like this one I took at the Panda zoo outside of Chengdu:

# ? Feb 7, 2023 20:24

BalloonFish: Jun 30, 2013; Fun Shoe

Nebakenezzer posted:

Thanks for posting this; people have been referring to this for awhile, but it's nice to read the facts.

Sidebar: I am a little confused as to why being shot with a 20mm cannon was so ineffective. Because you don't slash it with fire, it just pokes two 20mm holes in the balloon, and it turns out that's a slow leak? I do get that they give the balloon so much gas, and that expands as altitude increases. Is the gas in the balloon in equilibrium with air pressure once max altitude is reached?

Sagebrush posted:

It's a very, very small overpressure. Like less than 1000 Pa, or about 1% more than atmospheric pressure. Comparable to inflating your car's tire to a reading of 0.15 psi.

Quoting myself from two years ago in this thread:

BalloonFish posted:

The big zeppelins had very thin gas bag skins - at most the thickness of a few of sheets of paper laminated together - so the leakage/diffusion rate was quite high. Over the course of a year of regular use a zeppelin would use over 100% of its lifting gas, lost through a combination of diffusion, leakage and deliberate venting.

Blimps used a thicker, heavier skin with much lower diffusion rates and the USN found that helium-filled blimps could sit in a hangar for well over a year and lose only 4-6% of their lifting gas. In active use that rate would increase due to pressure venting and added leakage.

This was one of the factors with helium v. hydrogen as a lifting gas - hydrogen could be readily replaced while, in the cast majority of the world, helium could not and certainly not cheaply. While hydrogen offered a slight but useful boost in lifting capacity volume-for-volume, in reality it offered much greater lift because a hydrogen airship could be fully inflated on the ground at the start of its journey and then could afford to vent hydrogen to prevent over-pressure in the bags as it climbed and to compensate for the burning of fuel as it travelled because it was easy to install hydrogen filling facilities at each stopping point. Helium airships usually had to cast off with their bags under-pressured so they would be at maximum pressure at cruise altitude without venting, which decreased the effective payload far more than the difference in the density of the gases themselves would suggest. To get any decent range helium ships also had to have some sort of system to recover water from the engine exhaust gases to take on ballast as fuel was burnt since they couldn't afford to vent gas. That was further in-built weight which robbed payload. The true solution, but used only by the Graf Zeppelin, was to use blaugas as fuel, which had virtually the same density as air and so the ship's weight hardly changed as it was used.

The very low differential pressures between a lifting gas in an airship and the atmosphere, coupled to the sheer size/volume of the big rigid airships, was one reason why they were so hard to destroy in military use. The R100/R101 gasbags each had four vent tubes which were usually sealed, folded over and tied shut but were opened to deflate the bag for inspection or repair. With all four tubes open the vents totalled seven square feet in area and it took around half an hour for 70% of the gas to escape, at which point the differential pressure was so low that deflation basically stopped. In WW1 the RNAS calculated that a two-foot diameter hole in the top of a gasbag would not be critical damage to a large airship since the rate of gas loss would be so slow (and the loss would be limited to a single bag) that the airship would run out of fuel before the bag lost significant lift.

# ? Feb 7, 2023 20:43

Beef Of Ages: Jan 11, 2003; Your dumb is leaking.

Speaking of hydrogen: https://www.seattletimes.com/business/boeing-aerospace/faa-clears-hydrogen-powered-airplane-for-first-flight-at-moses-lake/

# ? Feb 7, 2023 21:54

FuturePastNow: May 19, 2014

coldpudding posted:

Hey wait a min hasn't the US been spending billions of dollars on airborne lasers? Slicing up a big balloon sounds like an ideal test case for such a thing.

They used a brand new off the line 747 for that Airborne Laser and then canceled the program and scrapped the plane with virtually no hours on it

# ? Feb 7, 2023 23:05

Luigi Thirty: Apr 30, 2006; Emergency confection port.

`Nemesis posted:

landed in the ocean but they know exactly where and you can bet your rear end they will be salvaging the debris.

I think they already announced it landed in relatively shallow water (like 8-9 fathoms) so no problem recovering it.

Yeah, it does seem like an airborne laser would be good for ripping up balloons, doesn�t it?

Going back to hydrogenchat, one of the problems with balloon-busting that made it so dangerous in WW1 wasn�t the cables or nets, it was that the incendiary ammo required to ignite the gas was only effective out to about 300 meters, and a rickety biplane made out of balsa wood and steel cable isn�t going to like being near a large hydrogen explosion.

And before they had incendiary machine gun ammo, people were essentially attaching Roman candles to their planes and firing them at the balloons at ranges closer to 100 meters.

Luigi Thirty fucked around with this message at 23:37 on Feb 7, 2023

# ? Feb 7, 2023 23:28

Godholio: Aug 28, 2002; Does a bear split in the woods near Zheleznogorsk?

FuturePastNow posted:

They used a brand new off the line 747 for that Airborne Laser and then canceled the program and scrapped the plane with virtually no hours on it

They got to the point where they'd done everything they really needed that platform for. They'd proven the big concepts, and smaller, cheaper lasers could be used going forward.

# ? Feb 8, 2023 00:31

mobby_6kl: Aug 9, 2009; by Fluffdaddy

Godholio posted:

They got to the point where they'd done everything they really needed that platform for. They'd proven the big concepts, and smaller, cheaper lasers could be used going forward.

Sure but I still want a 747 with a giant freaking laser on it

# ? Feb 8, 2023 00:40

mllaneza: Apr 28, 2007; Veteran, Bermuda Triangle Expeditionary Force, 1993-1952

Serjeant Buzfuz posted:

Any landing you walk away from...... Right??

e: I keep imagining that scene from ST Generations where the Enterprise saucer crashes into the ground.

I like the crash of the Cerritos (in a holodeck program) in Lower Decks, mainly for what the saucer does,

https://www.youtube.com/watch?v=QQIDjdhFou8&t=42s

# ? Feb 8, 2023 01:00

Lord Stimperor: Jun 13, 2018; I'm a lovable meme.

mobby_6kl posted:

Sure but I still want a 747 with a giant freaking laser on it

I would even take it without the laser

# ? Feb 8, 2023 01:00

Midjack: Dec 24, 2007

Godholio posted:

They got to the point where they'd done everything they really needed that platform for. They'd proven the big concepts, and smaller, cheaper lasers could be used going forward.

Lower the power and rent it out to fly loops around Burning Man or something.

# ? Feb 8, 2023 01:09

Hadlock: Nov 9, 2004

mobby_6kl posted:

Sure but I still want a 747 with a giant freaking laser on it

Also a better option than the current thread title

# ? Feb 8, 2023 03:20

Hermsgerv�rden: Apr 23, 2004; Møøse Trainer

I know this is likely harder than I can possibly imagine, but what about launching a bunch of weights that are trailing cables or wires to entangle the gondola. I picture some sort of guided rocket that could carry the worth�s and trailing cables. My theory being that it wouldn�t take all that much to overcome the buoyancy provided by the envelope and now you have the whole payload to study and also a valuable chit to negotiate with the PRC.

# ? Feb 8, 2023 04:40

ryanrs: Jul 12, 2011

Trailing wires and weights would really gently caress up your missile efficiency, guidance, everything.

And China was never expecting to get any of their junk back in the first place.

# ? Feb 8, 2023 05:21

BIG HEADLINE: Jun 13, 2006; "Stand back, Ottawan ruffian, or face my lumens!"

mobby_6kl posted:

Sure but I still want a 747 with a giant freaking laser on it

Too bad, you'll get an AC-130J with a laser on it and you'll LIKE it, Mister: https://breakingdefense.com/2022/09/afsoc-ac-130j-gunship-to-fire-laser-weapon-in-flight-test-in-2023/

# ? Feb 8, 2023 06:14

HookedOnChthonics: Dec 5, 2015; Profoundly dull

Hermsgerv�rden posted:

I know this is likely harder than I can possibly imagine, but what about launching a bunch of weights that are trailing cables or wires to entangle the gondola. I picture some sort of guided rocket that could carry the worth�s and trailing cables. My theory being that it wouldn�t take all that much to overcome the buoyancy provided by the envelope and now you have the whole payload to study and also a valuable chit to negotiate with the PRC.

l m a o 'valuable chit'

lmao

lol

tho to give some credit to this incredibly silly post i do really appreciate the 'first as tragedy; then as farce' angle on reinventing Star Wars except this time aimed at the dastardly, deadly threat of... scary balloons

HookedOnChthonics fucked around with this message at 06:36 on Feb 8, 2023

# ? Feb 8, 2023 06:18

Humphreys: Jan 26, 2013; We conceived a way to use my mother as a porn mule

I've got an idiot friend thats 'JUsT aSKiNg qUEsTIoNS' trying to find any little error in ANY form of media reporting to suggest the US is lying and the Chinese aren't to blame.

# ? Feb 8, 2023 10:16