The speed limit in the US is 1000mph, else it’s a munition.
Please note: my apologies in advance for a comment that may be perceived as pedantic, but I just wanted to further illuminate this statement.
The U.S. regulation, which technically falls under the Export Administration Regulations (Navigation and Avionics), does not exclusively regulate GPS navigation in munitions applications; rather, it serves to regulate any airborne application where the GPS receiver is capable of resolving navigation telemetry at speeds in excess of 600 m/s. This equates to approximately 1,968.5 ft/s, or 1,342.16 MPH.
Given the speed limitation parameter of the aforementioned regulation, this regulation would not only apply to GPS receivers in munitions applications, but it would also apply to GPS receivers that are utilized in fighter aircraft, space vehicles, etc.
Is is really for missiles. Same reason the ITAR limits for accelerometers and gyros are relatively high (I think like 10g for acceleration). Same again for vibration tolerance. It is a barrier to entry for making a navigation system for missiles.
I fail to see what is so hard to believe that an actor _could_ use civilian parts to get military capabilities. Yes, sure the are points about performance and reliability and what not but I can't shake the feeling that at least some of those points are exaggerated or marketing speak and the re is obviously a point where these components are good enough to be dangerous.
There's a few other restrictions as well as the 1000mph speed limit, as far as I'm aware.
GPS is still slightly inaccurate in its publicly available form: there's a second frequency broadcasting an encrypted signal, and with both frequencies you can better account for variations in the ionosphere.
Galileo I believe will shortly be the only system with worldwide coverage and publicly available multiple-frequency broadcast.
ITAR regulations restrict GPS for civilian use to a maximum altitude and maximum velocity, but this is solely a software limitation that is increasingly becoming less relevant.
Although selective availability has been disabled for a very long time, even before SA was turned off it was easily possible to get a precision measurement by integrating over time as the SA error was pseudo-random. It is also possible to use things like the phase information from the non-civilian 'encrypted' signals to increase accuracy even though the data cannot be decoded. Some survey-grade receivers were doing this even before SA was disabled, and it's pretty standard now in the precision GPS world.
Your understanding of GPS is quite out of date. GPS began adding a second L2C frequency for consumer use 15 years ago, and started ramping it in 2014. They are in fact in the process of adding a third civilian signal called L5. You can get accuracy from the consumer signals <10cm while in motion today with the right receivers and antennas. L5 will make it more robust indoors and give higher accuracy with cheaper antennas.
Galileo is great, but I wouldn't be holding it up as a crown jewel of GNSS. They have had some major missteps and operational issues in the recent past.
For consumer applications, multi-GNSS receivers are really where it's at. Combining GPS + GLONASS + Galileo + BaiDou is not simply an excercise of comparing the resultant positions given by each networ, but actually being able to combine the information to produce a single faster or more reliable measurement. For instance, getting a 3d position from 2 GPS satellites + 2 Galileo satellites when ordinarily you would not even be able to get a 2d position from either network in that situation.
You don't have to wait for the full fleet to cycle before you can use L2C or L5. L2C is already 15 years into its rollout and is widely available despite still being "pre-operational" due to it not having 100% coverage at all times.
You also missed discussing L1C, the 4th civilian signal being introduced with GPS III. This will work primarily with L5 to enhance indoor accuracy.
A good example is shock absorbers designed for vehicles heavier than 30 tons. It has all kinds of civilian uses in heavy machinery, but since that's a key tech for armored vehicles, they are also on the munitions list. The same applies for rocket and jet engines above certain parameters, all kinds of space imaging technology, etc, etc.
Russians call everything a rocket anyway. RPG-7 is a rocket, Saturn V is a rocket, Sidewinder is a rocket. They’re not confused about it, they regard all to be in the same category.
It’s a bit political than technical that in American English guided rocket weapons are always called “missiles“. Same reason as J in NASA JPL stands for _jet_ though they don’t normally do turbine jets.
So calling non-military rockets as munitions could be, I think, potentially more straightforward.
> Russians call everything a rocket anyway. RPG-7 is a rocket
Bad example. РПГ is "ручной противотанковый гранатомёт", approximately "man-portable anti-tank grenade launcher". Its round, "ПГ-7" is "anti-tank grenade". Rocket-propelled grenade is a backronym.
Well, both the Atlas and Soyuz (currently used by NASA and Roskosmos) were developed primarily for the U.S. and Soviet militaries as ICBM vehicles, the Space Race was something of a PR operation.
After all, you don't really need to have an explosive payload: just dropping a heavy enough missile can be devastating.
Since kinetic energy increases with the square of velocity, if you can create a payload that can travel at hypersonic speeds (like a tungsten rod) without burning up then the amount of kinetic energy is in the tens of millions of joules. That's enough to destroy any single target, but doesn't have nearly the same destructive power as a nuke, which releases trillions of joules of energy.
According to the wikipedia article, the tungsten rods in question would be 9 tons and would deliver an explosion equivalent to that of 11.5 tons of TNT. Considering the cost of getting it into orbit, this is only a good idea when the advantages of the delivery method outweigh that cost. The advantages of "rods from God" compared to ICBMS are that they're twice as fast and have different dynamics vs early warning systems or anti-ballistic systems.
Sure, tungsten rods also work. What I meant was something far less sophisticated - "we don't care what specifically is hit, as long as it impacts in the general area." See e.g. the Qassam missiles, or similarly, the North Korean space program (or "space program"?) and Japan.
True, but unless you have hundreds of them, I'm not sure if it's useful for MAD (i.e. replacement for nukes).
I suppose if you made the tungsten rods heavy enough and made made them travel fast enough you could get kinetic energy on par with small nukes, but the problem is it's highly directional (i.e. most of the energy is released underground and absorbed by the earth), unlike a nuke which can release all of its energy at once in an airburst 100 feet above a city.
It would be useful as a PGM in the arsenal, but probably not enough for MAD in an arms race. I could be wrong, though.
I thought that limiting the GPS from the top was to complicate making cheap missiles, something that might be used by rogue states or terrorists; for MAD, you probably wouldn't choose COTS equipment.
I'm a software engineer at NASA and it's an annoying fact of life for us every day. There's a huge overlap in the technology, we just have different applications. In fact, a huge percentage of our airplanes are aircraft military aircraft.
There's still some verbiage around commercial products and embargoed countries, but realistically, North Korea and Iran have access to OpenSSL, so it hardly matters.
Another interesting class of dual-use technology are fast power switching elements. And both modern SMPSs and Class D audio amplifiers are worryingly near to what would have to be considered a “munition”.
I believe the US used to make their GPS slightly inaccurate, but this was done on the satellite side.