Why GPS Automatically Shuts Itself Down Above 1,200 mph

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[@tparadox88]

I've been told that the restriction was changed from OR to AND after cases like the Felix Baumgartner balloon jump demonstrated that there can in fact be legitimate civilian uses at extreme altitude or velocity.

[@nikoladd]

Cool now my jumping homemade ICBM can use GPS..

[@BRAZILIAN_MIKU]

​​@@nikoladd only if it goes below 60k ft or 2k km/h

[@gigitrix]

"OR" is cheaper to implement too - they only have to support one of the two

[@RBRT02]

@@BRAZILIAN_MIKU you mean 2 Mm/h?

[@gamingwithtmenna1282]

@@RBRT02 what????

[@acf2802]

FYI: It's much easier to build your own GPS receiver than it is to build your own missiles. At least that's what I've discovered. You're first on my list, Garmin.

[@jur4x]

Also, who is most likely to attempt nuking US? China and Russia. And they both have their own sat nav systems.

[@dustinbrueggemann1875]

@@jur4x It definitely makes it harder for tin-pot dictators to accelerate their missile programs by purchasing American consumer goods though. You don't really want Kim Jong Asshole being able to build missile avionics 10x cheaper like that.

[@vigilantcosmicpenguin8721]

Unless it turns out Garmin also has a missile arsenal.

[@darin7553]

It was Garmin all along

[@Jaker788]

There's still a locked precise mode for missiles and rockets. Without that precision, your missile will accumulate enough slight errors and end up way off course or lose control and crash. You need to be a vetted rocket company or the military to have access to that.

[@Tarkov.]

I'm old enough to remember the scrambled GPS signals. My dad was a Ham radio enthusiast, and as such he was into all kinds of techy stuff like handheld garmin GPS. I fondly remember going to the park, and him showing me how it works, and that it can record your path and you can use that to find your way out of the woods...but that it wasn't very accurate, so you needed a LOT of space for each dot to show up. And that's why we were at the park, because my backyard isn't >300x300ft

[@marsgal42]

Hence Differential GPS (and now WAAS). A beacon listens to GPS, compares where it knows it is and where GPS says it is, broadcasts correction data.

[@ryanroberts1104]

LOL! I remember having an old Garmin with nothing more than an arrow pointing towards my desired waypoint in a straight line. I remember being totally lost in a city and that was all I had to follow...took like 150 miles to go 30.

[@stinkymart3173]

That's interesting to a young guy. Nowadays I press a button in my planter tractor and it steers for me, within 1 cm of accuracy. And I get grumpy when I lose it lol

[@nutzeeer]

I remember a very old gps with a black and white display and no stored map. You could only save your position on an empty map as dots. Might be useful in the wild though.

[@ryanroberts1104]

@@nutzeeer Yep...if you saved enough dots you could make a track to follow. But memory was limited, and every turn had to be manually entered!

[@joshuasims5421]

It’s amazing that astronauts can make it to the ISS so easily when google maps shuts off minutes after takeoff.

[@TheWaynester101]

They use landmarks along the way to guide them

[@77seven77]

@@TheWaynester101 😂

[@chr1styn806]

They probably use Apple Maps instead.

[@d4fs33k3r]

What do you think they train so hard for all those years? Map reading and alien languages to ask for directions obviously

[@elmurcis1]

They use land based laser guidance system - if they can see laser every minute, they are on correct route.

[@justineldridge2956]

I'm currently one of those nerds designing a high altitude baloon for a summer internship and our team has been wondering why none of the GPS sensors worked above a certain altitude... thanks for the oddly telepathic and prompt answer

[@karanaima]

well you know what you have to do now... send the letter to the department of commerce

[@Tinil0]

I'm actually shocked that a group of nerds designing a high altitude balloon wouldn't know this. It's not exactly arcane and esoteric knowledge, and is extremely relevant to what you are doing. Are you sure you guys should be doing this?

[@NoNameAtAll2]

there are circuit designs that get around this limitations of gps chips

[@HesderOleh]

@@Tinil0 That is exactly what I was thinking. This is such common knowledge I was surprised that this was even an HAI video.

[@xynyde0]

@@Tinil0 " Are you sure you guys should be doing this?" Because they decided to do it, they came across this interesting fact about GPS. This is how many people learn stuff, by doing activities on the field. No need to discourage someone.

[@stevenjlovelace]

1983: Let's open GPS to the public to keep planes out of Soviet airspace. 2016: Let's use GPS signals to catch cartoon animals.

[@robertjarman3703]

Or Santa Claus.

[@NatetheNerdy]

Need context on the 2016 thing

[@bandvitromania9642]

@@NatetheNerdy c'mon did you miss the whole Pokemon GO? Lmao

[@hayleyxyz]

@@NatetheNerdy i clicked on your profile and ended up with spider monstergirl vore asmr wtf lol ("sugar" channel) I love the internet

[@NatetheNerdy]

@@hayleyxyz It's not vore, she "eats" you in another way.

[@RealCreepaTime]

00:28 "Twelve-hundred miles per hour" *On screen 12,000 MPH* we all do a little oopsie sometimes haha

[@neeneko]

it does not take all that many zeros till the number doesn't really matter ^_^

[@Fuyu-Tsubaki]

Was gonna comment the same thing lol

[@iangolden6454]

Glad I’m not the only one who noticed

[@esthervarinreitman5546]

What’s a couple zeros between friends?

[@ryanair4713]

This is going to be in the mistakes video lol

[@EverythingExceptThat]

Thanks Sam! Will keep this in mind when designing my next intercontinental ballistic missile.

[@madensmith7014]

Make it fly at 1199mph at 55000ft and you're golden

[@user-ew5vj1sl1u]

Ferb, I know what we are gonna do today.

[@4_youtube_is_dead]

bruh

[@nikoladd]

Naah just make it stop and find where it is occasionally and then change course.

[@vigilantcosmicpenguin8721]

@@madensmith7014 Well, that's not nearly fast enough! It'll get detected immediately!

[@prim16]

4:37 I wouldn't put it beyond Tom Scott to write a letter to the US government about that.

[@nickvanruiven]

Signed, Mad Cap'n Tom

[@isheamongus811]

Do u know that there is Russian GLONNAS and private Gallileo. They can be used for middle or balloon. Theroeticly....

[@the_retag]

@@isheamongus811 galileo isnt exactly private, its EU run, but commercially/civilian focused. Has military capabilities too tho

[@ccktravis4128]

1:43 Determining ground location Determining a location, also known as "taking a fix", normally requires two or more measurements to be taken to produce a 2D location. In the case of the modern GPS system, dozens of such measurements may be taken depending on which satellites are visible at that time, each one helping improve accuracy. In the case of Transit, only a small number of satellites were in orbit and were spread out. This generally meant there was only one satellite visible at any time. Some other method of determining a second measurement was needed. Transit did this by measuring the signal's Doppler shift. The spacecraft traveled at about 17,000 mph, which could increase or decrease the frequency of the received carrier signal by as much as 10 kHz as measured on the ground. While the satellite is approaching the ground station its signals will be shifted up in frequency, and as it recedes they will shift down again. The precise moment when the frequency is exactly equal to the broadcast frequency is when the satellite's ground track passes the ground location's location (with some corrections). This provides one of the two measurements needed. For the second measure, one has to consider the pattern of the Doppler shift. If the satellite passes directly overhead, its angular velocity as it passes will be more than if it passes to one side. In the extreme case, with a satellite near the horizon, the relative velocity change is minimized. Thus the rapidity of the change in frequency is an indication of the relative longitude between the station and the satellite. Additionally, the rotation of the Earth provided another Doppler correction which could be used to determine whether the satellite was to the east or west of the ground station. These measurements produce a relative location compared to the satellite. To determine the actual location, that relative measure is applied to the location of the satellite. This is provided by periodically sending out precise time hacks (every two minutes), plus the satellite's six orbital elements and orbit perturbation variables. The ground receiver downloaded these signals and calculated the location of the satellite while it was measuring the shifts. The orbit ephemeris and clock corrections were uploaded twice each day to each satellite from one of the four Navy tracking and injection stations. The Transit satellite broadcast on 150 and 400 MHz. The two frequencies were used to allow the refraction of the satellite radio signals by the ionosphere to be canceled out, thereby improving location accuracy. The Transit system also provided the first worldwide timekeeping service, allowing clocks everywhere to be synchronised with 50 microsecond accuracy. Calculating the most likely receiver location was not a trivial exercise. The navigation software used the satellite's motion to compute a 'trial' Doppler curve, based on an initial 'trial' location for the receiver. The software would then perform a least squares curve fit for each two-minute section of the Doppler curve, recursively moving the trial position until the trial Doppler curve 'most closely' matched the actual Doppler received from the satellite for all two-minute curve segments. If the receiver was also moving relative to the earth, such as aboard a ship or airplane, this would cause mismatches with the idealized Doppler curves, and degrade position accuracy. However, positional accuracy could usually be computed to within 100 meters for a slow-moving ship, even with reception of just one two-minute Doppler curve. This was the navigation criterion demanded by the U.S. Navy, since American submarines would normally expose their UHF antenna for only 2 minutes to obtain a usable Transit fix. The U.S. submarine version of the Transit system also included a special encrypted, more accurate version of the downloaded satellite's orbital data. This enhanced data allowed for considerably enhanced system accuracy [not unlike Selective Availability (SA) under GPS]. Using this enhanced mode, accuracy was typically less than 20 meters, i.e. the accuracy was between that of LORAN C and GPS. Certainly, Transit was the most accurate navigation system of its day. The basic operating principle of Transit is similar to the system used by emergency locator transmitters (ELTs), except that in the latter case the transmitter is on the ground and the receiver is in orbit. ELTs measure the Doppler shift of the transmitter on the boat or aircraft as it passes overhead and forwards that data to the ground where the location of the craft can be determined.

[@hsko8007]

🤓

[@FutureCommentary1]

Everything I didn't know I wanted to learn about the evolution of GPS. Thanks for being so generous with your knowledge.

[@AlanTheBeast100]

GPS needs 2 + 1 for a fix at a known altitude (on the sea), or 3 + 1 for a 3D fix. The extra sat is to correct the local clock.

[@JamesBond-xx1lv]

I'm really thankful you decided to share your knowledge. However, I only read the first 3 sentences and got bored. I'd recommend publishing your books in the future instead of leaving it in a KZbin comment.

[@morkovija]

Like holy cow. What a comment. Thanks man!

[@CoBzu]

Love the Tom Scott reference with garlic bread!

[@Dave_Sisson]

Sam is making fun of him because Tom is the only factual KZbinr with over twice as many subsc6ribers as he has.

[@DissociatedWomenIncorporated]

@@Dave_Sisson to be fair SciShow has 7-odd million. So maybe Tom is the target because he’s a factual KZbinr _and_ has a name with a similar structure to Sam.

[@TriNguyen-he7xk]

@@Dave_Sisson or it's just nothing. Like it literally meant nothing there's no hidden meaning or motive. Ever heard of occams razer? Not everything has a Machiavellian narrative behind it

[@alexc8461]

"Oh no, I am a missile" -Tom Scott

[@danielschein6845]

I worked on some of the early commercial auto GPS systems as an intern in engineering school. Someone figured out that you could unscramble the GPS signals simply by putting a receiver at a known location and comparing where GPS said it was to the actual location. It could then send out a correction factor to all receivers in the area. Who funded this project? The US Coast Guard.

[@jpaugh64]

That last part about the Coast Guard is the only part I hadn't heard before. It raises so many new questions! Why didn't the Coast Guard have access to the full precision in the first place? Also, why were they so comfortable spending tax dollars to subvert the law? Dang!

[@kaitlyn__L]

@@jpaugh64 The answer to your first question is because they’re not quite military, and the answer to your second question is that they were military enough 😉

[@jpaugh64]

@@kaitlyn__L Funny! 🤣 Actually, I bet they needed civilian GPS systems to be effective in order to conduct search and rescue at sea. 300 sq ft is a pretty big area to search, especially in stormy weather. Not to mention that out-of-date communication with the "lost" party, and the way that boats can drift in a current would all decrease the accuracy even further.

[@kaitlyn__L]

@@jpaugh64 there was a guy with the Coast Guard who tracked bits of debris as they drifted for decades, to build computer models about how things drift based on ocean weather data. (These models now enable rescue of dozens of ships a week, which otherwise wouldn’t be found in time.) Perhaps his project was even involved in OP’s work; such as if they could only buy civilian units in the quantities required, but needed the higher precision of the scrambled military signal to be useful.

[@a2e5]

@@jpaugh64 Cost and availability, always these two. I recall they shut down SA during gulf war because too many on-the-ground US personnel was themselves using civilian units and getting lost.

[@FacterinoCommenterino]

Today's fact: If an alpaca has blue eyes it is most likely deaf.

[@bababababababa6124]

Lucky them, they don’t have to listen to HAI videos 😂

[@Dynothru]

@Bully Maguire 🅥 What, your dad? Nah, you wished

[@bababababababa6124]

@@Dynothru generous to assume he had a dad in the first place

[@jamesvancam]

@@bababababababa6124 so why are you here then? Not hard to avoid someone's content.

[@jamesvancam]

You already said this fact before bot.

[@bill-clintongaming]

This was actually a question that I had a while ago. I was driving my car a little bit above the speed limit and my gps just stopped working. Thanks for explaining this for me.

[@clayel1]

yo how fast were you going??

[@vigilantcosmicpenguin8721]

@@clayel1 Fast enough that the traffic police couldn't even see the car was there.

[@wellsilver3972]

The speed limit was 700 💀

[@ekiM2K]

Where were you going above the speed limit? The Autobahn

[@redexxx]

Well "a little bit over the speed limit" might be an understatement 😂

[@scottfranco1962]

"GPS was for submarines"... actually to be more accurate it was for ICBMs launched from submarines. Submarine launched ICBMs had a problem. Although submarines have a very good self contained navigation system called inertial navigation, it is not as accurate as say, a land launched ICBM launched from a tube in the ground that has been well surveyed for an exact location. The problem is that the ICBM gets its initial launch position from the submarine carrying it. Of course, where else would it get it. The submarine could SURFACE and get a better position, but that not only takes time, but would make the sub vulnerable to attack. In fact it negates the whole idea of a sub launched ICBM, which is to be able to attack the target at depth and even perform evasive maneuvers after launch so that the ICBM's launch point after leaving the water does not directly reveal the sub location. An ICBM can only correct its aim while in boost phase, after which it becomes, as the "B" in ICBMs implies, a BALLISTIC Missile, that is with a course set by Sir Issac Newton. Before GPS, sub launched ICBMs used the navigation coordinates from the sub that launched it. It has an onboard inertial navigation system and that was set to the location of the sub which it left. And that is the system it used to guide the boost phase to reach it's target. With GPS, the missile has time to get an accurate position after leaving the water to get a better position from the satellite, and can improve the accuracy of its targeting. In fact, it helps quite a bit, and (no surprise) it set off an entirely new argument about ICBMs being used for first strike capability, yada yada.

[@joelshewmaker3567]

So if your intercontinental ballistic missile is travelling at 59,999 feet and 11,999 mph, you don't need to worry about your navigation shutting down.

[@theenzoferrari458]

At that speed and altitude it won't make it

[@BrainPermaDeD]

@@Eskay64 I think I kinda guessed that(maybe) because nukes are not going to hit the target(distance can be well, all over earth) if they are that slow and fly that low. Predator missiles(cruise missiles){You may call me a CoD semi fan but idc(Predator Missiles usually go 30-90m in altitude and at a speed of 800 kph with an average range of 1000km)} are not facing much of a problem because targets are kinda closer to launching station. So we can conclude that predator missiles(cruise missiles) can go below the gps limit but ICBMs can't.

[@victoriaregina8344]

Would be useful, except after the missile has made all its corrections, its following a fix route 🤣

[@AlanTheBeast100]

COCOM is speed AND altitude, so as long as one of the two is in bounds, all is well. With Transit you could use a single satellite to get a very precise position - just took a pretty long time.

[@kennethng8346]

If I remember correctly, Transit worked on the doppler shift as it went overhead. So it was very good for east-west positioning but not north-south, unless you had an accurate clock and the conversion book for the orbital mechanics.

[@AlanTheBeast100]

@@kennethng8346 Yes, Doppler based, but polar orbits. I don't believe there was an error axis much greater than the other because the sats didn't have to pass over you - their lateral offset was "information" too... (Doppler shift would not reach minimum before going downshift)

[@jhoughjr1]

not really. U need at least 2 points to fix a location and realistically 3

[@Hodaggium]

Another perk of an accurate GPS signal is I can use multi million dollar satellite equipment to find tupperware in the woods, meaning I'm a Geocacher.

[@floraldystopia]

*Me not pausing on the Wikipedia article* HAI saying I was cool and hated science for it *Me going back and pausing to see it*

[@jordandnc]

same but im 1 but not the other

[@jordandnc]

as in cool yes and hates science no and i will erase that but i added

[@Yanni_X]

But… if someone would build a nuclear missile using GPS, why wouldn’t they just build their own gps-receiver? I don’t think there are any reasons why you would have to use an US-exported GPS-Receiver, are there? Just measure the signal and calculate the position using your own hard- and software

[@Skyler827]

Maybe the signals are encrypted?

[@jaykoerner]

Anyone with money to build one today can do that now, back when they first banned it, it was less of a problem since the stuff required to build one easily wasn't as readily available. That and now between glonass, starlink and a few other constellations they are so many options you positioning It really doesn't matter

[@witchofengineering]

Well, you're right, that's exactly what people do. I know one suborbital sounding rockets space startup that did exactly that just made their own receiver to track their rocket.

[@xb70valkyriech]

But it still prevents some jackass from trying to make guided missiles out of model rocket parts. Won't stop a serious government or large organization, but it still inhibits lone actors

[@jaykoerner]

@@witchofengineering I assume theoretically you can use the GPS receiver to tell where you are outside of their orbit as well?

[@jdatlas4668]

Oh, I know this one! It's actually either height or speed, and that's been an issue for hobbyists sending balloons into the upper atmosphere, so new chips now only shut down when you exceed *both* speed and altitude.

[@leo_warren]

It can be either once one condition or both conditions are met, Tom Scott did a video years ago.

[@jdatlas4668]

@@leo_warren hey, that might quite possibly be why I know :D

[@ppstorm_]

Lmao people just vote up any false shit they see in the comments without checking

[@xb70valkyriech]

Some badly made chips would shut down if only one condition was met. But the nicer ones would wait until both conditions were met. However, you had to change the settings on each chip by sending the proper string upon startup. I used to do research with high altitude balloons and this was a huge PITA for us. Check out my comment for detailed instructions.

[@jdatlas4668]

@@xb70valkyriech interesting! Nice to get some insight from someone with first hand experience :D

[@crowonthepowerlines]

0:53 Damn, the new DOD logo is awesome.

[@quinn.iamdefinitelycisgend2542]

well there go my weekend plans

[@kyufuyuvbvbllymjnncuhuhbuh7538]

It's morbin time

[@spacemanmat]

Those nerds of us who build there own rockets also get locked out. Most GPS units are optimised for horizontal movement, they tend to freak out when you subject them to 35G vertically. Will typically take them the rest of the flight up till they figure out where they are.

[@sphericalcat1434]

2:09 that joke aged like milk

[@boduholm8463]

A GPS satellite is a marvel of modern engineering. The reason why you can see four satellites is that it is the minimum to pinpoint your location. The GPS works by sending out a super-accurate time code in a spherical shape. So the first satellite gives your location on a sphere. The following satellite provides your position in a circle where the signal from both satellites meets. The third satellite gives your location at two points. Now you are actually pointing to an area on earth because the other area is the same distance away from the satellite into space. So why the fourth satellite? Most of us cannot afford an atomic clock in all our devices, so the fourth satellite is for timing.

[@PrograError]

also ya GPS also takes cellular data for that extra accuracy... that's why the GPS only mode is shat.

[@Add_Text_Here]

This summary is so misinformed, it's unbelievable.

[@NGC1433]

It's like you didn't even try to get a clue how it works...

[@NGC1433]

@@PrograError It's same accuracy in either mode, it just takes a lot of time to collect almanac if it is GPS only. Give it some time and accuracy will be identical.

[@thomasrinschler6783]

GPS is one of the few everyday things that has to take both special and general relativity into account...

[@fdude4]

You wrote 12,000 mph and said 1,200 mph. Also I see the limit for the speed is 1,999 mph. Good to know when I make my own missle

[@smallant.]

Was looking for this comment lol

[@thekamakaji]

As a college rocketry teams former avionics lead, this very specific limitation has cost me hundreds of hours of sleep

[@hiddennamesftw]

At 0:29 you say 1200 miles per hour put but 12,000 miles per hour on screen. Can I be in the mistakes video?

[@sambarocas]

Noticed it too lol

[@johnholleran]

Having been a balloon nerd in my college days, I distinctly remember reading an "and" in the law. But yes, there is a spreadsheet of which GPS units get over 60kf for the high altitude balloon community

[@shawnjoseph4009]

The GPS limit also affects HPR, or High Power Rocket, flyers, since using GPS to know where your rocket is is useful, and lots of HPR rockets do fly fast enough to trigger the speed barrier on their GPS chips.

[@jingles123456789ify]

Lmao what a shot taken at Regan

[@paisan8766]

Valid shot

[@jingles123456789ify]

@@paisan8766 It's a valid shot of EVERY US president

[@foty8679]

@@jingles123456789ify every goverment head*

[@paisan8766]

@@jingles123456789ify actually, yes

[@alexmallace4886]

US made Inertial Measurement Units also often have export restrictions because the are too close to ones used in ICBMs- so to use them in middle eastern countries for surveying/ nav purposes you have to get a European made version of the certain IMU which has downgraded sensors

[@stevenabbott7508]

It also effects rocketry enthusiasts/college rocketry clubs! A few years ago a number of universities completed to become the first to send a rocket to the karman line (the limit of space) and it made detecting that the rocket actually reached that point *much* harder, since the karman line is significantly higher than 60,000 ft.

[@ukraineme96]

Finally I get to be that guy… you can add this to your end of year mistake montage! At 0:30 you say 1200 but show 12,000 on the screen :).

[@Matthew_and_Ami]

Yes I was confused too and about to post this as well you say 1200 but you show 12,000 which is it?

[@Liv_buggy]

I was just about to say it! Honestly look forward to finding these mistakes

[@AntonFetzer]

This is actually quite a problem for CubeSats. My university is building CubeSats and we want to put a GPS receiver on board. We managed to get our hands on a unlocked GPS receiver, but that was not easy and we had to sign quite a bit of legal stuff that prevents us from giving our CubeSat to Russia or China.

[@HenryLoenwind]

You could just have ordered one from China that wasn't made to be sold in the US and isn't a 1:1 copy of one. They rarely bother to put that restriction in for those.

[@bltzcstrnx]

China and Russia have their own global navigation. That particular restriction is totally useless.

[@rasimbot]

​@@bltzcstrnx | The restrictions are built into commercial GPS-chips. But you can always build your own GPS-receiver using general-purpose of the shelf components. It just will not be as compact, lightweight and power efficient as a solution with dedicated GPS-chip. And you can create your own GPS-chip if you have competence. So Chinese or whoever can use unrestricted GPS along with BeiDou easily

[@bltzcstrnx]

@@rasimbot IIRC, I've read somewhere that the US can disable unencrypted GPS signal on certain region. This is done on Operation Desert Storm and Iraq Invasion, although I wasn't so sure on this. The US ability to do this is a major motivation for BeiDou.

[@rasimbot]

@@bltzcstrnx | Yes, but my point was that restricting GPS-chips is useless for a capable user anyway -- even if they don't have their own satellite nav system. If public GPS is disabled (as you say) in that user's area then it no longer matters whether their chips are locked or not

[@YHK_YT]

0:04 I hate when that happens the chimps really are slow

[@MrA6060]

That one shot with the airplane then saying "an incident in September" oh no... "1983" oh cool

[@Squareheed]

Love the 'US Military' at 1:51, that have British gear and a British assault rifle lmfao

[@turbo_marc]

We still dumped a bunch of your tea into the ocean.

[@Squareheed]

@@turbo_marc No you didn't dump anything of ours into the ocean. Some people hundreds of years ago dumped some tea into the ocean, nothing to do with us today.

[@Lensandwander]

Love the british that invaded my homeland (scotland) (this is a joke)

[@Squareheed]

@@Lensandwander Scotland doesn't exist, its East Northern Ireland now

[@Lensandwander]

@@Squareheed what?

[@georgeprout42]

Ah, I remember the selective availability days... Not fondly, but I remember them. Also, nice nod to Tom Scott at the end

[@YoniIsrael]

0:12, in that case i just ask the Country Road to take me there

[@existentialselkath1264]

If you've got the resources to make anything that goes that high that fast, surely you could just bypass the restriction if its built into the gps receiver? Or is it a hard limit from the satalites themselves?

[@harryspeakup8452]

There are surplus military aircraft out there that you could buy for a few hundred thousand dollars that could exceed these height / speed limits. Having a few hundred thousand dollars and some jet fuel does not mean you can build a GPS receiver from scratch

[@chr1styn806]

Yeah, it seems like the know-how for "designing GPS receiver" is almost a prerequisite for "designing ICBM"

[@MartheenCahyaPaulo]

While there's no hard limit from the satellite signal itself (it's just time, identifier, and orbits of the whole constelation), building from scratch or modifying existing receiver isn't that easy especially back when the restriction were made. Today sometimes it's as easy as downloading patched firmware.

[@thekwoka4707]

It's not from the satellites as the satellites are passive. They only broadcast. Your reciever, as the name implies, only receives. So it has to be at the reciever side that it does the GPS calculations and then goes "woah woah you're out of bounds". GPS recievers are entirely their own little module in devices like phones.

[@Berkeloid0]

There are already SDR (software-defined radio) projects that can receive raw signals from the satellites, so you can already build your own GPS receiver that bypasses the limits. The real issue is, if you were a serious threat attacking the US, they could just temporarily scramble the whole GPS system, rendering your GPS receiver useless.

[@gbphil]

The limits started off as low as 100mph. I had / may still have a Garmin GPS38 point to point handheld GPS and strapped to my motorcycle, its display would go blank at just 100mph. The word at the time was that it was to prevent rudimentary auto guidance systems similar to the trend of mobile phones being used as a trigger.

[@ChilapaOfTheAmazons]

Some *Chinese GPS chips* actually don't have this limit for some reason. Like those that you might find in the cheapest wristband GPS activity trackers. Don't ask how I know. 🤪

[@Zero_Gravitas]

I remember when there was that one guy in New Zealand blogging his construction of a GPS guided cruise missile in his garage and there was an entire section on finding a GPS that worked above the limits.

[@purduephotog]

I remember that! Was using explosion thrust... Shoot what's the name. Pulse jet?

[@Zero_Gravitas]

@@purduephotog Yep, pulsejet/pulse detonation engine. There's people on youtube making them and sticking them on gokarts these days.

[@enekuda05]

As someone who used GPS every day (Land surveyor) it's insane that you can get to within a half inch of accuracy nearly all day long off GPS now. But the equipment to do so costs nearly what a brand new mid sized car, fully loaded, cost lol

[@GiantEnemyMudcrabz]

Agreed. That feeling when you get 30+ sats and see that vertical go below 0.010m makes me appreciate that some guy did all this 100 years ago with a steel tape and a jar of whisky. Hell its not much more than 20 years ago a GPS unit was a big backpack that got only 4 sats on a good day.

[@kennethng8346]

What I found amazing was the sub milimeter accuracy for the sensors monitoring earthquake fault lines. But those units required you to be still for a very long time to correlate out the noise.

[@OneMadPhotographer]

I remember when you could visit a gas station and pick up a free road map. They were made out of paper, folded up neatly so you could keep it your glove compartment.

[@kevh6303]

But did they have a lady voice giving directions?

[@OneMadPhotographer]

@@kevh6303 There's a fence around the railroad tracks now, after a lady voice told some drivers to turn onto the train tracks.

[@YoloLP1]

0:29 12,000 or 1,200 feet?

[@KittyKatMan93]

My favorite thing on KZbin lately is seeing a HAI/WP video in the suggestions of videos Tom Scott did on the exact same topic 8 years previous.

[@a64738]

One time my GPS calculated my average speed in my car to 2300km/h over a 750km distance... It happened when it did run out of batteries during the trip and was of for most of the ride :)

[@TowerCrisis]

Yep... My buddy dabbles in amateur rocketry, big boys like 12ft tall rockets. They regularly run into these restrictions. You'll suddenly loose GPS tracking as soon as it hits mach 1.5, then regain it as soon as it pachutes down past the altitude restriction. I believe they do record the altitude measurements and store that data onboard though, but you can only retrieve that data if you can recover the rocket or it regains connection whilst descending

[@sarpbakrsoy8125]

The GPS shuts itself down you say? Well, I won't go 1,200 mph with my car then.

[@stevenlubick2689]

Good idea 😊 😊 👍 👍

[@r6u356une56ney]

Gotta love how the narrator said "all the sudden" but the captioning fixed it to the *correct* wording "all of a sudden"..

[@civetbutlemonbutmouse6087]

2:47 wow they were pulling a rick astley

[@TheElusiveReality]

the constitution quote and the reagan jokes, *chef kiss*

[@sambarocas]

Mistake at 0:29 wrote 12000 mph instead of 1200

[@petergerdes1094]

What potential adversary has the ability to make an ICBM but not to put together a GPS receiver that breaks those limits? Yes, many countries may not be able to fab their own chips but nothing stops them from just buying a radio receiver for those frequencies and reimplementing the location /velocity calcs themselves on an FPGA or whatever.

[@Jaker788]

No person or group is capable of using GPS for an ICBM even with their own receiver unless they know the encryption code to the restricted radio. Open civilian GPS signals are not accurate enough for a missile and you'll end up with a crashed missile.

[@petergerdes1094]

@@Jaker788 For a nuclear ICBM as uses by the kind of countries that might even sorta have the temptation (north Korea) they don't need pinpoint accuracy. It's only thd big nuclear powers whose nuclear doctrine involves breaching hardened bunkers where you need to hit precisely. Besides, according to Wikipedia a civilian unit with clear view of the sky should be accurate to within 5m and that's before you even use any fancy tracking based GPS solution integrating inertial data etc..

[@Hotdogenthusiast]

I thought he was going to say regan was conflicted because on one hand, innocent people were killed, but on the other hand the North Koreans were justified because to them it looked like a foreign plane from an enemy nation was entering their territory. Needless to say I was caught off gaurd by the Joke.

[@cdvideodump]

Finally it's not here

[@ooooneeee]

@@cdvideodump thank you for mocking bots 😂

[@223556762308]

It was over Russia and it had some of the most influential conservatives on board.

[@42VS42]

That "The Thing" reference made my day. So glad I'm not the only one who thinks that when they hear that.

[@gunnargu]

I read an article once where a guy implemented GPS himself and just didn't have the limit. So I suspect that any serious attempt into using GPS on a missile wouldn't be stopped by this limitation.

[@rasimbot]

There is open source GPS receiver for software defined radio

[@Mathtron5000]

It goes "Oh no, I am an Intercontinental Ballistic Missile" and shuts down

[@kippy7883]

KZbin used to queue the garlic bread video after every HAI video, till one day I fell asleep watching HAI and didn’t wake up until Tom had launched garlic bread into space and driven a billion dollars worth.

[@CreeperOnYourHouse]

I've run into this problem a few times in my 1986 Volvo 240, I always lose my direction and get lost.

[@foty8679]

Volvos are great

[@CreeperOnYourHouse]

@@foty8679 great handling at mach 3.

[@ultimate50s98]

As an Ohian the joke about Ohio was halarious, I love how my stae is both very populated and very rural at the same time.

[@dale116dot7]

Ohio is also quite famous in supplying a very important component of the warhead on top of an ICBM.

[@lonelyPorterCH]

and now, nobody could imagine a world without gps^^

[@nishant54]

Absolutely we can via Galileo, glonass, beidou and navic etc.

[@RoflcopterLamo]

@@nishant54Yea but they dont got that three letter ring that Governmenst love ❤️

[@benstreicher5411]

Not me pausing to actually read the wiki article then immediately getting roasted

[@mossivy9627]

Thank you for making the ultimate procrastination videos

[@ryanreedgibson]

Reagan wasn't smart enough to be conflicted. Remember, he is the same guy that pushed "trickledown".

[@sunvieightmaster88]

GPS is something so interesting and mysterious. So, This is interesting.

[@Cxrruptwd]

"welp, I'll create my own gps with access to other satellites" - A random person

[@caliman99]

FYI: Narration and title say "1,200 mph." First graphic reads "12,000 mph." Great video as always!

[@cactuscreek5925]

0:29 can't wait to see that one in the next edition of HAI makes mistakes

[@jj02mc27]

Man, I hate it when I'm going 1201 mph in my 2006 Honda Civic and my GPS stops working

[@jnawk83]

seen this joke again and again. why is it always a honda civic?

[@nickl2852]

1:42 paused and full screened. You totally should have covered that. It was super interesting...

[@The_Vanished]

Yes, Ohio. When you're always in the city and also off the grid simultaneously

[@erilassila409]

I love how you almost name-dropped Tom Scott 😂

[@Visualized_Music]

4:53 looked so weird

[@kasparvg]

Thanks, now I know why I get GPS trouble while cruising on the highway at almost Mach 1.6

[@pierce25]

As an Ohioan I can confirm that shockingly, gps is also here!

[@Vehicular.Shenanigans]

SAM YOU PUT 12,000 MPH @0:28 you absolute pinecone

[@airplanenut6242]

It’s also a bit of an issue for amateur rockets at higher power levels

[@foty8679]

Cant they just use Glonass or Galileo? Galileo is said to have 10x the accuracy of gps (it has like cm accuracy rather than meters)

[@maxthycom]

@@foty8679 I'm actually working on such a rocket and the issue is that there aren't that many manufacturers around. Espacially not in Europe where I'm from. You unfortunately can't just choose which network you use. Most available receivers support gps glonass and galileo but are made in the US and subject to those limits. We had to buy a special receiver for big $$$ to get around the limits.

[@silverXnoise]

Those Buckeye subs deep beneath the surface of Ohio are going to be O.K. !

[@realight_]

Thanks, this was SOOOO useful, know i know why my GPS shuts down when im in a normal street at 1,200 MPH, THAAAANKS youuuuu

[@Posh_Quack]

2:00 IT WORKS IN OHIO???

[@SydMakesStuff]

Nice subtle shot at Tom Scott there with the garlic bread balloon.

[@maximilianmorse9697]

I think they mentioned this on the WAN Show a week or two ago, is that where you got the inspiration?

[@tomihawk01]

I don't remember it being on the WAN Show. Are you sure you're not thinking of A Problem Squared because it was a big part of one of their episodes.

[@maximilianmorse9697]

@@tomihawk01 actually now that I think of it it might have been a Tom Scott video

[@connor8610]

Oof that shot a Tom Scott there, atlest when he does science subjects is uselly quite fun

[@brenanconroy4052]

I do wonder how this will go with supersonic aviations supposed return with Concorde definitely able to exceed both the maximum speed of GPS and the altitude, and the Boom Overture set to be able to do the same, will there be a carveout for SSTs?

[@harryspeakup8452]

We used to manage just fine without GPS on SSTs. Inertial platforms are cheap and super-reliable now too compared to when they were first used for airliner navigation. As long as you have a good GPS fix while you are at lower levels and speed, the places where there are actually other things you might hit, then inertial nav will be fine to take you through the cruise and you can re-establish GPS as you decelerate out of max cruise and head down. Top of descent on a Concorde used to be around 200 miles from destination so if you have GPS for that, as well as your departure and acceleration phase, that's really all you need

[@Hollows1997]

Air Traffic Control and pre planning routes.

[@goobot1]

The max is artificial to prevent foreign powers from using us tech against it. They can just not artificially limit it for things like that

[@Jaker788]

Are airplanes not exempt from this restriction?

[@goobot1]

@@Jaker788 commercial airplanes don’t go anywhere near that fast

[@LittleWhole]

That brain animation was very, very unsettling.

[@NOrlando952]

Great to know for my commute to work in my SR-71 Blackbird.

[@briananspach5210]

Fellow Ohioan. Love the jabs

[@AbdullahBasit24]

"you're in your 2006 Honda Civic" *shows a picture of a 2014 Honda Civic*

[@jmlemmi]

Great! Client side restrictions for warheads. Thank god noone could just erase them from their GPS software, when they implement a Ballistic Missile targeting computer.

[@Jaker788]

There's still server side restriction. There's a whole frequency that's encrypted and not for civilian use, high enough accuracy for a guided missile unlike civvie GPS frequencies.

[@marsovac]

@@Jaker788 maybe a missile that need to hit a small building, but an ICBM needs to hit a city. You could do that with a system that predated GPS and was less accurate than civilian GPS.

[@SOME1HING]

Obviously the real reason was Yujiro Hanma taking a walk.

[@_jannis]

What about GPS receivers which use instead of Navstar Galileo and/or Glonass, they could work above this limits and make the balloon nerds happy.

[@brammeijer5411]

the Tom Scott reference, absolute gold

[@nitehawk86]

2:39 Your damn telescope is not only backwards, you are looking into the wrong bit.

[@rhebucks_zh]

he couldn't film that one clip

[@mt_xing]

Nice to see the audio glitch from the Nebula upload got fixed.

[@asdanjer]

I always wondered who came up with this random bs. Do they seriously thing someone able to build a gps guided missile can't build there own gps chip or modify one?

[@neeneko]

I think people underestimate just how big a leg up being able to get low cost off the shelf components can be for both developing and deploying expensive systems.

[@asdanjer]

@@neeneko that is definitely true in comerical applications. But in a low volume production with a military application this isn't that big a deal. Developing a gps guided missile probably coasts hundreds of millions at the absolut minimum. And building them coasts a millions a pop. In a cenario like this, while still being an advantage, not having a off the shelf gps module is just not that much of a problem.

[@captainheat2314]

those are military contracted cruise missiles prices which those costs are way higher due to very high profit margins and also you don't need to develop cruise missiles as they already exist since you don't need the latest tech for them to function

[@neeneko]

@@asdanjer thing is, this is something that militaries are currently struggling with due to the chip shortage, and something that has impacted places like Iran for decades.

[@asdanjer]

@@neeneko yea ok you are right on this one. It is not gonna help prevent someone from building it but it definitely gonna make it a bit harder and can therfor reduce volume.

[@colorado841]

Oh okay that explains why my phone gps cut out immediately after I swallowed those LSD tabs.