The SR-71 Astroinertial Navigation System, aka R2-D2, was crucial in Blackbird mission. Here’s why.

The Aviation Geek Club ^ | 8 Aug 2021 | Dario Leone

[DUMBGRUNT]

...From 80,000 feet, it could survey 100,000 square miles of Earth’s surface per hour. Piloting the Blackbird was an unforgiving endeavor, demanding total concentration. But pilots were giddy with their complex, adrenaline-fueled responsibilities. “At 85,000 feet and Mach 3, it was almost a religious experience,” said Air Force Colonel Jim Wadkins. “Nothing had prepared me to fly that fast… My God, even now, I get goose bumps remembering.”

The ANS was the 1960’s version of GPS, but instead of using satellites to locate itself, the ANS used the stars. This is because before the invention of the modern satnav networks there wasn’t a way to navigate the SR-71 in the areas where it operated. The SR-71 needed to be able to fix its position within 1,885 feet (575 m) and within 300 ft (91 m) of the center of its flight path while traveling at high speeds for up to ten hours in the air.’

‘The ANS works by tracking at least two stars at a time listed in an onboard catalog, and with the aid of a chronometer, calculates a fix of the SR-71 over the ground. It was programmed before each flight and the aircraft’s primary alignment and the flight plan was recorded on a punched tape that told the aircraft where to go, when to turn, and when to turn the sensors on and off. The stars were sighted through a special quartz window (located behind the RSO cockpit) and there was a special star tracker that could see the stars even in daylight.’

[DUMBGRUNT]

the flight plan was recorded on a punched tape that told the aircraft where to go, when to turn,

A relative had his classwork on punched tape. thinking it was good to go he moved on to the printer.

The printer fires up, massively!!! Everyone looks at the action!

He grabs the stack of paper and nods approvingly to the waiting students.

Out of sight, he dropped it in a dumpster; because he did not have a clue what went wrong.

[KC_Lion]

For your interest.

[BenLurkin]

Palmdale California Blackbird Air Park SR-71 U-2
https://www.youtube.com/watch?v=AGP70S3ZBpQ

[frank ballenger]

I was impressed when I first learned that birds use the positions of the stars to navigate for long distance night travel such as migration to the South.

A place called Pathwayz.org said
How do birds use magnetic fields to navigate?

Researchers found some specialized cells in birds’ eyes that may help them see magnetic fields. It is thought that birds can use both the beak magnetite and the eye sensors to travel long distances over areas that do not have many landmarks, such as the ocean. Jan 4, 2021

Wonder what other things we cannot sense that animals can, or early versions of humans could sense. The hippies were onto something about “The vibes went bad so I split.”

[fso301]

I say websites that do not use a font color well contrasted with the background should be deplatformed.

[one guy in new jersey]

A sunshade is needed for that. Kinda long, baffles, matte black paint. Many sunshades have/had mechanical shutters that activated when the angular separation between the sun and the star being tracked was too small. Thus one probably didn’t have the complication of a shutter because they had the ability to choose from among many different stars with sufficient angular separation from the sun prior to each particular mission.

[one guy in new jersey]

Thus one = This one

[Yo-Yo]

Star Tracker/INS navigation wasn’t exclusive to the SR-71. B-52s, KC-135s, and ICBMs all incorporated Star Trackers to supplement their drift-prone gyro INS systems.

[DUMBGRUNT]

—” websites that do not use a font color well contrasted with the background should be deplatformed.”

This one is actually viewable, some have the text totally camouflaged, highlight it to view it.

[fso301]

This one is actually viewable,

Barely. Why couldn't they use black as the font color? What purpose was served by using a grey font?

[Governor Dinwiddie]

Amazing how birds navigate! They can fly 10,000 miles almost non-stop and end up exactly same place they were the year before.

It is claimed that dogs can sense the earth's magnetic field. Some Dogs will align themselves north-south when they have a bowel movement. I tested this theory on my dogs, and it seems to be true. They don't care which way they pee, but they are usually aligned on a north-south axis (within about 15 degrees either way) when they poop. They don't seem to care if the head is north or south, but the body will be aligned north-south (more or less).

[Tallguy]

Neat trick, those birds ‘seeing’ the earth’s magnetic field. But is it accurate enough to find the Primary target, the ICBM complex at Laputa. Target reference Yankee Golf Tango Three Six Zero.

— Major Kong wants to know where to take the turn for the final run in to the target.

[DUMBGRUNT]

—” their drift-prone gyro INS systems.”

And all this time I always thought it was the Air Force guys giving the Grunts in the back a ‘thrill ride’.

On one ancient beast, we were rocking about 45 degrees each way!
It had an observation port in the roof(?) for a sextant and the monsoon was POURING in! The crew was taking turns attempting to seal the hatch.

I don’t know if taking on enough water would sink us, but didn’t want to find out.

Finally, they were able to slow the leak, and they were totally wet.

[DUMBGRUNT]

“Well, boys, we got three engines out, we got more holes in us than a horse trader’s mule, the radio is gone and we’re leaking fuel and if we was flying any lower why we’d need sleigh bells on this thing... but we got one little budge on them Rooskies. At this height why they might harpoon us but they dang sure ain’t gonna spot us on no radar screen!”

A great speech from a great movie.

[frank ballenger]

I can see in your aura that you getting too technical for me.

[Pollard]

That's when I cheat. Double click on a word to highlight it. Right click and then click Inspect. Find font-color & font-weight. Change color to #000 aka black and change font-weight to something heavier like 6-700.

Typically it would be "p" for paragragh or would be "body" but in this case it's ".front" that needed to be changed. Just changing the color to black didn't really help because the font is so thin. Refreshing the page makes those changes go away. The Web Inspector is part of Web Dev Tools that most browsers have. It allows you to change css properties of elements on the page. Same can be done with the background color of a page for when people use a colored background that doesn't contrast with the text. Can change the background to white. If the background of the page is an image, find the img src property and uncheck the box next to it. There are plenty of youtube videos that will show you how to use Web Inspector as well.

[Pollard]

[ckilmer]

In my bible study, we call the presence of the holy spirit — the sixth sense. An invisible means of support as well.

[tet68]

I read somewhere that German fighter pilots eyes were so
good that they could see stars during the day time.

[fso301]

There are plenty of youtube videos that will show you how to use Web Inspector as well.

Very interesting. Thanks!