GPS - unreliable

[alfsauve]

When I was "in" the mantra was for each weapon system (plane, boat, tank...) to be totally independent of external signals.  To that end not only was celestial navigation, which navies had used for centuries, but inertial based navigation was the up and coming thing.  With it, if you set in your position before you departed, then it could without any outside input compute where you were at any time.   Subs first used it not for security but because they couldn't access outside signals anyway.

Somewhere along the line GPS became the thing and the whole idea of independence from outside signals sort of faded. But always in the back of my mind and I suppose many others where, we're back to relying on an external signal.  At first not a big deal as few players, if any, had the capability of messing with it.  Times have changed.  GPS is jammable and capable of being spoofed these days.

Proof?

In the far eastern reaches of Finland GPS has become so unreliable due to Russia interference during the Ukrainian conflict that they are resorting to older land based radio signals (DME/TACAN/VOR) for their airports.

https://yle.fi/a/74-20123117


And some wonder why I carry a printed Atlas in my bug-out bag.

[Rastus]

I am right there with you!  I too keep an atlas. 

However, mine is the large print edition. 

[Big Frank]

My DeLorme atlas covering the state of Michigan is 120 pages, 124 if you count the covers, and 11"x15.5". That's only 0"x1.5" shy of TWO 8.5"x11" sheets of paper joined together. I can see the ~1/3 mile long driveway (or lane) at my uncles' farm on page 107. Page 106 has the triangle shaped Raco Field which is close to the family cabin and an old CCC camp. It was also a Bomarc "Boeing Michigan Aeronautical Research Center" supersonic ramjet powered long-range surface-to-air missile (SAM) site from 1959 to 1 October 1972. So, up until I was 11 years old there was a missile site with 28 missiles, armed with either a large conventional explosive or a 7–10 kiloton W40 fusion-boosted fission nuclear warhead, just a few miles from the cabin and I never knew it until a couple years ago. The Bomarc A had a cruising speed of Mach 2.8 at an altitude of 66,000 feet and a maximum range of 250 miles. The Bomarc B had a new booster that required less space in the missile, so more ramjet fuel could be carried, giving it a range of 430 miles.

Raco Field was a satellite area of Kincheloe Air Force Base in Kinross 18 miles away. Kinchloe is now the Kinross Correctional Facility and Raco Field is Smithers Winter Proving Grounds, a testing site for vehicles and components in harsh winter climatic conditions. It features over 750 acres of snow, ice (approximately 40 acres) and bare pavement surfaces and is staffed by more than 40 employees proficient in creating and maintaining a variety of snow, ice, and dry area surfaces. The Test Center is used by manufacturers of vehicles ranging from small automobiles to Class 8 trucks, vehicle components (both OE and aftermarket), snow handling equipment, construction equipment, recreational and seasonal sport vehicles and military equipment. Smithers Winter Test Center has 17 separate testing areas for testing all types of vehicles and components. There was another Bomarc missile site at K. I. Sawyer Air Force Base in Marquette. The county airport, Marquette Sawyer Regional Airport, now occupies a portion of the base and has scheduled airline flights and some general aviation activity.

A Bomarc A with a nuclear warhead caught fire at McGuire AFB on 7 June 1960 after its on-board helium tank exploded. While the missile's explosives did not detonate, the heat melted the warhead and released plutonium, which the fire crews spread. The Air Force and the Atomic Energy Commission cleaned up the site and covered it with concrete. This was the only major incident involving the weapon system. The site remained in operation for several years following the fire. Since its closure in 1972, the area has remained off limits, primarily due to low levels of plutonium contamination. Between 2002 and 2004, 21,998 cubic yards of contaminated debris and soils were shipped to what was then known as Envirocare, located in Utah. McGuire AFB was on one side of a chain-link fence, and Fort Dix, NJ where I took basic training was on the other side of the fence. That one area was closed but McGuire AFB was still open in 1979 and 1980 when I was at Fort Dix. Now it's part of Joint Base McGuire–Dix–Lakehurst (JB MDL).

Eartha is the world's largest rotating and revolving globe, is housed in a three-story glass gallery at the former DeLorme Headquarters in Yarmouth, Maine. Garmin purchased the company and the building in 2016. The globe weighs approximately 5,600 pounds (2,500 kg). Just over 41 feet in diameter, the enormous structure was designed as a scale model. At the scale of 1:1,000,000, or approximately one inch equaling 16 miles. Eartha is tilted at 23.5 degrees, just like Earth, and is rotated about that axis by an electric motor. Simultaneously, a second motor swivels the entire tilted, rotating globe around the attachment point to the floor, together giving a approximation of Earth’s own simultaneous day-night and annual cycles. It takes about 18 minutes for Eartha to complete a cycle. While the map store that housed Eartha is now closed, the sales agreement allows the globe to keep rotating.

https://www.atlasobscura.com/places/eartha-delorme-headquarters

https://en.wikipedia.org/wiki/Eartha

https://en.wikipedia.org/wiki/Raco_Army_Airfield

https://en.wikipedia.org/wiki/Boosted_fission_weapon

https://en.wikipedia.org/wiki/W40_(nuclear_warhead)

https://en.wikipedia.org/wiki/CIM-10_Bomarc

https://www.smithers.com/industries/transportation/automotive/winter-proving-grounds