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High altitude object shot down

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High altitude object shot down

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Old 15th Feb 2023, 05:37
  #241 (permalink)  
 
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Old 15th Feb 2023, 07:34
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A couple of answers to that.

1. At 60K an F-22 will have to be supersonic. To do a gun attack on a static balloon and break away without hitting it would be difficult, far easier just to use a missile. The cost of an AIM-9X is $400K which, in military terms, is an insignificant factor.

2. They wanted to bring down the balloon just as it crossed the coast in shallow waters, which meant the envelope had to to be shredded. Previously attempts to engage balloons with guns had only made holes where the helium slowly leaked ou making it slowly deflate and fly on for hundreds of miles. The AIM-9X has a fragmentation warhead which, as seen, did the job.
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Old 15th Feb 2023, 10:40
  #243 (permalink)  
 
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Originally Posted by michaelbinary
Just went through some free fall calculators that take into account air resistance, and a 100g object falling at its terminal velocity would be around 8KPH. And a baseball weighing around 150g would fall at approx 9KPH. So slower than I originally guessed.
Hmmm... I'm by no means an expert - although I do own a parachute I've never tried opening it - but I've a nagging suspicion that weight isn't the only determining factor for terminal velocity...
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Old 15th Feb 2023, 10:56
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Originally Posted by pasta
I've a nagging suspicion that weight isn't the only determining factor for terminal velocity...
Gosh, what other factor could there be, I wonder ?

Originally Posted by michaelbinary
went through some free fall calculators that take into account air resistance
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Old 15th Feb 2023, 11:10
  #245 (permalink)  
 
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Some experimental evidence
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Old 15th Feb 2023, 11:12
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Originally Posted by DaveReidUK
Gosh, what other factor could there be, I wonder ?
I dunno, the only property given for this hypothetical projectile was its weight:
Originally Posted by michaelbinary
Just went through some free fall calculators that take into account air resistance, and a 100g object falling at its terminal velocity would be around 8KPH
I can't be bothered to do this as more than a thought experiment, but I'd hazard a guess that the terminal speed of a 100g dart is rather more than 8km/h. A 100g solid lead sphere will achieve a higher terminal speed than a hollow plastic sphere of the same weight. No idea of the terminal speed of a 100g helium balloon, but at sea level it'll be in the opposite direction...
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Old 15th Feb 2023, 11:23
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Originally Posted by pasta
I dunno, the only property given for this hypothetical projectile was its weight:


I can't be bothered to do this as more than a thought experiment, but I'd hazard a guess that the terminal speed of a 100g dart is rather more than 8km/h. A 100g solid lead sphere will achieve a higher terminal speed than a hollow plastic sphere of the same weight. No idea of the terminal speed of a 100g helium balloon, but at sea level it'll be in the opposite direction...
Just doing a back of an envelope (OK, calculator) calculation. The Mythbusters video said that a free falling bullet will achieve 150 ft/sec. I make that to be 164 kph, which is a bit more than 8 kph.
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Old 15th Feb 2023, 15:10
  #248 (permalink)  
 
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I think our adversaries may be trying to deplete our economy. Two $400k missiles to take down a $50 balloon. That doesn’t include the costs for the aircraft to fly the mission.
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Old 15th Feb 2023, 15:10
  #249 (permalink)  
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The payload apparently dropped free of the balloon when it was struck by the missile, so clearly dropped a lot faster than the balloon itself.

The debris was spread over a wide area, so it probably broke apart in mid air.

For example, I assume the solar panels ripped off before the payload hit the ocean, unless the attachment points were extremely sturdy. The antennas might have ripped off too.

The rate of fall reflects weight and surface area, which is why a feather lands more slowly than a cannonball unless it is in a vacuum. They have a very different terminal velocity.
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Old 15th Feb 2023, 16:37
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D Tel today: Six Russian balloons spotted over Kyiv

There is a roaring northerly over Kiev, so from where were these launched?

E & OE
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Old 15th Feb 2023, 17:03
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Originally Posted by langleybaston
D Tel today: Six Russian balloons spotted over Kyiv

There is a roaring northerly over Kiev, so from where were these launched?

E & OE
Belarus?
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Old 15th Feb 2023, 18:07
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Originally Posted by visibility3miles
The rate of fall reflects weight mass, and surface area/coefficent of drag, which is why a feather lands more slowly than a cannonball unless it is in a vacuum. They have a very different terminal velocity.
Quite right (with a couple of minor adjustments).

Rather surprises me that people supposedly professionally trained in the subjects of drag and weight and aerial velocity appear to have never heard of Galileo's experiment at the leaning Tower of Pisa - in 1590 or thereabouts.

https://demonstrations.wolfram.com/G...ngTowerOfPisa/
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Old 15th Feb 2023, 18:18
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A missile is still a waste of money (outside of any training budget)... could they just ram the damn thing, or at least fly close enough to burst it with the shock wave?
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Old 15th Feb 2023, 18:30
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Originally Posted by Petit-Lion
A missile is still a waste of money (outside of any training budget)... could they just ram the damn thing, or at least fly close enough to burst it with the shock wave?
Hmmm - what do you believe the survivability of an F22 is, when ramming something (even a balloon) at Mach 1±?

F22 - $210 million
AIM-9x - $0.4 million
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Old 15th Feb 2023, 21:20
  #255 (permalink)  
 
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Originally Posted by Petit-Lion
A missile is still a waste of money (outside of any training budget)... could they just ram the damn thing, or at least fly close enough to burst it with the shock wave?
Razor blades on the wing tips
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Old 15th Feb 2023, 23:36
  #256 (permalink)  
 
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Sorrryyy....but this doesnt make any sense at all....so, from one week to another everyone in every corner of this planet are shooting down balloons...!!???

Now Ukr says it shooted down six of them in a row, and until now no wreckage found at all, like all the others in US, Canada, etc...!!???

https://www.reuters.com/world/europe...ls-2023-02-15/

My apologies...but theres more than meets the eye here...and, once again the excuse of balloons...USA, Canada, China, Russia, Ukr, Eastern Europe, Japan, ... i give up... until this very moment only the first one was a balloon, The Chinese in US...all the rest only God Knows (or even some other few).
I really cannot understand why people keep doing math, trigonometry, physics...etc...but no, we are not talking about balloons here, period!

Last edited by JanetFlight; 16th Feb 2023 at 00:26.
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Old 16th Feb 2023, 01:48
  #257 (permalink)  
 
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Why Janet, what do you think they are. Simple explanation is that everyone upped their surveillance when the Chinese Balloon became public and they are now shooting down objects everywhere that have probably ALWAYS been around, we just didn’t track them.
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Old 16th Feb 2023, 06:26
  #258 (permalink)  
 
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Originally Posted by HOVIS
I've not read the entire thread. Has anyone suggested a drone with razor blades on the leading edges? 😁
???


lol

cheers
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Old 16th Feb 2023, 09:09
  #259 (permalink)  
 
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Originally Posted by Ninthace
Razor blades on the wing tips
Back in the day, it was called "Starfighter". QF-104 was the unmanned version.
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Old 16th Feb 2023, 12:26
  #260 (permalink)  
 
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Originally Posted by Ollie Onion
Why Janet, what do you think they are. Simple explanation is that everyone upped their surveillance when the Chinese Balloon became public and they are now shooting down objects everywhere that have probably ALWAYS been around, we just didn’t track them.
Could be that... OTOH the images we're seeing of the downed stuff in Ukraine seems to show not much more that a simple met style balloon with radar reflector, so I wonder if it's a case of the Russians thinking "we'll have a go at wot the Chinese just did, well as best we can. It might give us a clue as to where some AD assets are and it means the Ukes might have to expend some ordnance...".

Doubt it's anything much more complex than that.
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