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The SR-71 Blackbird Astro-Nav System worked by tracking the stars

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Re: The SR-71 Blackbird Astro-Nav System worked by tracking the stars

#351

Post by the_biot »

hangonhn wrote: post #24

Anyone know if modern military aircraft have something similar? I imagine it would be even cheaper and easier to do these days given the processors and cameras we now have. Seems like a good backup to have.

I think we're seeing similar, or equivalent, technology being used in Ukraine right now. The Russians routinely jam GPS frequencies and have been doing so for years/decades (one of the few things the Russian military is considered good at).

Yet we see Ukraine doing precision strikes not only with long-range missiles, but also with all kinds of drones.

Re: The SR-71 Blackbird Astro-Nav System worked by tracking the stars

#353

Post by dredmorbius »

dredmorbius wrote: post #212
ethbr1 wrote: post #183

Earlier quoted context omitted.

My guess would be for physical calibration of the INS gyroscope rotors? https://navsource.org/archives/08/PolarisHistoryGEX1.htm (see bottom / appendix for examples of Polaris-era INS) Given the CEP they were aiming for, and amount of time they had to fiddle with them, I'd guess they started very carefully with the physical precision of components.

CEP: Circular error of probable or probability. The radius of a circle within which 50% of rounds will be found. For the V-2 rocket this was 4.5 km. For the Minuteman III missile, 240m. Blast effects decrease with the cube of the radius, so a more accurate weapon means a smaller effective warhead. The "Flying Ginsu" AGM-114 Hellfire missile has a CEP of 5 meters or less, and uses blades rather than explosives to mini…

Cites on the Hellfire which I'd intended to include above:

https://www.kabulpress.org/article89242.html>

https://metinmediamath.wordpress.com/2013/10/10/missile-accu...>

Re: The SR-71 Blackbird Astro-Nav System worked by tracking the stars

#354

Post by another2another »

helpfulContrib wrote: post #330
blincoln wrote: post #303

Earlier quoted context omitted.

"unique radio-electronic weapons based on new physical principles" sounds an awful lot like the breathless tales of secret Russian Tesla death rays that have been circulating since the 80s, if not earlier. If Russia could "neutralize entire armies with just one short electromagnetic impulse", or even just "disable missile warheads and onboard aircraft electronics miles away", don't you think they'd be using that capa…

> don't you think they'd be using that capability against Ukraine? No, and that's entirely the point . Their non-use of their advanced weapons systems is as equally interesting a subject as their forward-deployment of expendable, less advanced systems. The Russian military certainly have their inefficiencies - as all modern militaries do, including "our own" - but they also have capabilities that are going to be more…

Russia have thrown everything they have at Ukraine over the last year-and-a-half. Cruise missiles, hypersonic missiles, their best troops and naval assets.

Now they're buying equipment from Iran (!?) and North Korea.

Russia, in their deep USA envy thought they'd have their own Shock and Awe! 3 day SMO.

Instead they overestimated themselves, and massively underestimated Ukraine.

The cupboard is empty. The only thing they have left is nuclear weapons, which they're quite rightly terrified of using. All that remains now is a long slow and grinding defeat as Putin expends every available Russian male in his desperate attempt to remain in power and not back down.

Re: The SR-71 Blackbird Astro-Nav System worked by tracking the stars

#355

Post by helpfulContrib »

another2another wrote: post #354
helpfulContrib wrote: post #330

Earlier quoted context omitted.

> don't you think they'd be using that capability against Ukraine? No, and that's entirely the point . Their non-use of their advanced weapons systems is as equally interesting a subject as their forward-deployment of expendable, less advanced systems. The Russian military certainly have their inefficiencies - as all modern militaries do, including "our own" - but they also have capabilities that are going to be more…

Russia have thrown everything they have at Ukraine over the last year-and-a-half. Cruise missiles, hypersonic missiles, their best troops and naval assets. Now they're buying equipment from Iran (!?) and North Korea. Russia, in their deep USA envy thought they'd have their own Shock and Awe! 3 day SMO. Instead they overestimated themselves, and massively underestimated Ukraine. The cupboard is empty. The only thing t…

>Russia have thrown everything they have at Ukraine over the last year-and-a-half.

I don't believe that's the case. Russian military doctrine has always been to reserve the best systems for the end-game, and front 'fodder' in the beginning stages of things.

I see Russia's war theatre manifest also in Syria, where the very same tactics are utilized to suppress the field.

"Shock and Awe" is a US doctrine. Russian is more "Shake and Hold".

"Massively overestimating themselves/underestimating themselves", is very difficult to contextualize, if you don't actually speak Russian.

>The cupboard is empty.

I'm sorry, I really don't agree. You might want to take a deeper look:

https://www.cna.org/reports/2021/10/Russian-Military%20-Stra...

You must, of course, steel yourself for some whiplash. The world is not entirely as it "seems".

Re: The SR-71 Blackbird Astro-Nav System worked by tracking the stars

#356

Post by _kbh_ »

helpfulContrib wrote: post #355
another2another wrote: post #354

Earlier quoted context omitted.

Russia have thrown everything they have at Ukraine over the last year-and-a-half. Cruise missiles, hypersonic missiles, their best troops and naval assets. Now they're buying equipment from Iran (!?) and North Korea. Russia, in their deep USA envy thought they'd have their own Shock and Awe! 3 day SMO. Instead they overestimated themselves, and massively underestimated Ukraine. The cupboard is empty. The only thing t…

>Russia have thrown everything they have at Ukraine over the last year-and-a-half. I don't believe that's the case. Russian military doctrine has always been to reserve the best systems for the end-game, and front 'fodder' in the beginning stages of things. I see Russia's war theatre manifest also in Syria, where the very same tactics are utilized to suppress the field. "Shock and Awe" is a US doctrine. Russian is mo…

>> Russia have thrown everything they have at Ukraine over the last year-and-a-half.

> I don't believe that's the case. Russian military doctrine has always been to reserve the best systems for the end-game, and front 'fodder' in the beginning stages of things.

This still doesn't explain the BMP-T's, the T90's and S300's that are deployed to Ukraine and destroyed in Ukraine.

>>The cupboard is empty.

> I'm sorry, I really don't agree. You might want to take a deeper look: > https://www.cna.org/reports/2021/10/Russian-Military%20-Stra... > You must, of course, steel yourself for some whiplash. The world is not entirely as it "seems".

If the cupboard isn't empty then why are there ~80 smoldering T62's in Ukraine.

Re: The SR-71 Blackbird Astro-Nav System worked by tracking the stars

#357

Post by jki275 »

rjsw wrote: post #282
jki275 wrote: post #189

Earlier quoted context omitted.

You're overstating the problem to an extent. Pilots in WWII had things like the predecessor to TACAN to navigate with -- my grandfather was a pilot in the Army Air Corps and described navigation with radio beacons regularly. Aircraft Carriers don't move far in the short time CV based aircraft are up -- they just need to navigate back to where they took off from. That's not as hard as it sounds, even with 1940s techno…

Royal Navy carriers had homing beacons to help their aircraft find the carrier again. The beacon rotated once a minute, the pilots synchronized their watches to the beacon before taking off, when they heard the signal through their headphones the second hand on their watch would indicate the bearing back to the carrier. RN strike aircraft also had their own radar which made it easier to find things.

Yep! That would be the predecessor to our modern TACAN systems.

Re: The SR-71 Blackbird Astro-Nav System worked by tracking the stars

#358

Post by eru »

nojvek wrote: post #318
bookofjoe wrote: post #283

Earlier quoted context omitted.

>I know not with what weapons World War III will be fought, but World War IV will be fought with sticks and stones." ― Albert Einstein

We will have countries against each other fighting for their borders but world war is v unlikely in our lifetime. We love our cheap goods, cheap-ish energy and ability to change presidents and prime ministers. Yes China, North Korea and Russia banding against the rest of the world is a real threat but China has shown it is selfish too and cares more about its economy.

> Yes China, North Korea and Russia banding against the rest of the world is a real threat but China has shown it is selfish too and cares more about its economy.

I really want to believe that. But the same logic did not stop the first world war.

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