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back to article Iran spy drone GPS hijack boasts: Rubbish, say experts

Doubts that Iran managed to bring down an advanced US drone over the country last month using an advanced GPS spoofing attack have been raised by experts, who say that attacks of this type would be extremely tough to pull off. Iran announced on 4 December that it had captured an advanced American remotely piloted spy drone, …

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Silver badge

Maybe...

So spoofing is complex, but what would the drone do if it didn't have any valid GPS signal?

Without it it would have to rely on dead reckoning calculations, with only air speed, bearing and duration to work with to attempt to find its location. It would be off track and lost very quickly indeed.

In such a situation it could have a fail safe procedure, such as throttling the engine back and performing a controlled descent, or does it just keep zooming along in a lost style, hoping for a GPS lock, until it finally runs out of fuel and drops from the sky?

If it is the former, then spoofing the GPS signal with all its accurate timing would not be required, you just need to drown the signal out with garbage which should be a great deal easier given the weak signal sent from the GPS satellites.

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It may not get lost as quickly as you'd think. Assuming the autopilot works with an inertial reference unit, if that was used as a back up nav system it should be enough to have you within a few tens of miles after crossing the Atlantic. Even if it was just working of the Air Data Unit and the last known wind that's normally enough to make sure you land in the right country*.

I'd have assumed the fail safe procedure for a sensitive drone is to blow yourself up commit a terminal dive rather than risk being captured. After all they only got Gary Powers because he didn't take his cyanide pill.

*Having been made to do this for 'practice' on a few occasions it's generally good enough to get you near something large and obvious. So a drone should be able to get near enough to a radio beacon it can see.

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Raz

If I would design a drone, it will not be 100% dependant on GPS. Gyroscopes are very accurate these days and it should be able to know where it is based on that as well. When the GPS and gyroscope are sending conflicting information, it should trust the gyroscope. Tampering with it is a lot harder than jamming GPS, which must be considered as a probability in all conflict zones.

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Anonymous Coward

@Raz

You're forgetting changes in wind speed and direction.

Without any external references points navigation quickly becomes unreliable.

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Thw wind vector is easy enough to calculate

Holding a constant heading and airspeed for 20-30 seconds and comparing the result computed result with the GPS or an equivalently accurate inertial system, i.e. better than 5 metre accuracy, will also give a good enough windspeed to navigate by and is a method that can be fairly continuously updated. Alternatively, if either the inertial system or the GPS is working, you just fly 3-5 circles at a constant turn rate and measure the drift. Depending on turn rate, that need not take more than 5-10 minutes.

All sailplane navigation programs use the circling method to calculate wind. They update the wind vector every time you stop to circle in a thermal, and at least one of them uses the straight line method and can get an acceptable accuracy from 10 seconds of hand-flown straight, constant speed flight.

Don't forget the UAV will know its wind vector up to the point when the GPS signal gets jammed, so it should be able to get near enough to home to pick up an NDB or TACAN from its home field.

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Holmes

What it does

First of all, these systems don't rely entirely on GPS. They also have an Inertial Navigation System (INS) . INS's cannot be jammed, as they rely on nothing external to the aircraft to deduce location. While INS's are subject to what is called "integration drift" which means the uncertainty in it's location (according to the INS) increases with time, even after 24 hours of operation the uncertainty is enough for the drone to navigate back to base using INS. The INS can tell the unit if the GPS is being spoofed even if someone manages to spoof it, as the GPS location will differ from the INS location, and it's programming should give priority to the INS. These drones, if they lose the Command & Control link for a certain period of time, are programmed to return to base, and spoofing the GPS signal would not stop it from navigating its way back to base using the INS. One would presume that by the time it got back to base via INS, it would be out of GPS jamming range anyway. The fact that this drone did not fly back to base, assuming it did lose the C&C link, implies something malfunctioned.

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Holmes

Norfolk 'n' Goode: So bad, you're not even wrong.

Inertial Navigation Systems (INS) don't care about wind, etc.

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Meh

Never mind spoofing

Why is it assumed that GPS spoofing is the only way to hack a drone? The use of unencrypted control channels and even Windows as a control interface has been widely reported.

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Facepalm

Inertial Navigation.

I didn't think of that.

Doh!

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Difficult != impossible

This sort of exploit may be very difficult, but with some luck, may not be impossible. After all, think about all of the computer system exploits that have been declared "next to impossible" that have been successfully carried out...

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Speculation

Speculation from me, that is...

I believe GPS works by listening to a synchronised time signal from multiple satellite sources. You work out where you are by how far out of sync the signals are when you hear them. They're out of sync because you are different distances from the various sources.

Does this mean that the GPS spoofer could send the drone multiple signals from just one single transmitter, deliberately out of sync by the required amount to fake the drone's position?

ie. The drone doesn't know what direction the GPS signals are coming from, only that they are out of sync. It reverse engineers the delays to work out its location relative to each signal source.

It seems there would be no need for the attacker to use multiple antennas.

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GPS works by comparing the difference in transit time for signals from multiple satellites. This requires really accurate clocks in the satellites, really accurate knowledge of where the satellites are and fairly accurate clocks in the receivers.

Spoofing requires the transmitter to pretend it's a satellite and send out suitable rogue information, this isn't that hard and in fact some systems that improve GPS accuracy do exactly that just without the rogue information bit. The problem is even a lot of commercial GPS systems now have redundancy built in so that they use more satellites than required and switch between them in turn to check for a jump in position that would indicate an error in the signal.

For more on how GPS works try google, it really is very clever, especially the bit about using the special and general theories of relativity.

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Silver badge

All correct, and ...

Stone age GPS units had a tiny number of correlators and antennas that rejected left hand circular polarised signals. The satelites transmit right hand circular polarised signals, which get reversed if they reflect off something. Reflected signals arrive late, and made the GPS units report a position further from the satellite than reality. Also, when first switched on, the GPS would pick two satellites on opposite sides of the plannet, divide the correlators between those two, and give each a different guess at the time delay. If they found nothing, they would try other guesses or other pairs of satellites until they eventually guessed right.

Bronze age GPS units had lots of correlators. They could assign dozens to each satelite and find them from a cold start in seconds - unless the satelites were hiding behind buildings.

Modern antennas accept both left and right hand signals. This allows the GPS unit to get a signal when the direct path to a satellite is blocked. Modern GPS units expect to spot the satelite signal and multiple reflections of it. They assume the earliest signal is the right one, and the others are reflections. This allows them to remain locked on even if a satelite is temporarily hidden. Even if the GPS does lose its lock on a satelite, it has hundreds of correlators available to get it back again in under a second.

If you try to spoof a modern GPS, it will have enough information available to know something is wrong, but may not be programmed to recognise the problem or do something sensible about it. After all, the Americans know beyond all possible doubt that spoofing will always be well beyond Iran's technical abilities no matter how much GPS technology has changed since the first attempts to spoof them.

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Title not required

The GPS receiver needs to have some idea of (a) which satellites it is receiving timing information from, and (b) where those satellites actually are in the sky, so it knows how to triangulate its position. I would think that is why multiple antennas are required, to one for each of the GPS satellites that are being faked.

Also, I would find it hard to believe that a SPY drone wouldn't be designed in such a way to be able to continue being useful even in the event of a localized disruption of GPS. If I were designing such a drone, I would certainly take into account that just maybe the people I'm spying on might not be too keen on the idea and want to try and disrupt my spying in some way.

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Silver badge

Spoofing only needs one antenna

The receiver is receiving everything over one antenna and has no notion of direction etc. GPS rebroadcasters (used by GPS developers) receive the signal from all the satelites and just amplify and rebroadcast from a single antenna.

Having dabbled a bit in the GPS signal arena, I was quite surprised with the initial claims. While it is simple to swamp a GPS signal (because they are so weak), getting the timing right is a huge challenge. Some commercial level receivers designed to handle huge multipath (like the one in your Tomtom or phone) would perhaps be more forgiving, but I'd expect drones to use a top-shelf GPS or even a military grade GPS which have far tighter timing restrictions.

Spoofing commercial GPS is not impossible, but would be a hell of an accomplishment. Much simpler to chase the drone with a fast helicopter and chuck a net over it.

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Thumb Down

"Spoofing commercial GPS is not impossible, but would be a hell of an accomplishment. Much simpler to chase the drone with a fast helicopter and chuck a net over it."

Your taking the piss now i assume. Forget about how fast the drones average speed is for a moment (hint: to fast) and just think about altitude, then take a brick to your head and see if you can fly that high.

"The unnamed Iranian boffin told Christian Science Monitor that Iran developed the attack after reverse-engineering previously captured or shot down US drones, and by taking advantage inherent weaknesses in the GPS navigation system."

This should tell us all we need to know about the GPS spoofing and Iran and by that I mean, the Iranians never made the claim.

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Black Helicopters

@Charles Manning

I’m inclined to agree with you, I can’t see how it would be possible to capture a drone by tampering with the GPS signal, first you would have to capture the signal from same GPS satellites (at least 4)that the drone is using to establish position, rebroadcast the signal quickly enough so that the drone does not break lock, then you would have to start 'adjusting' the signal to change the drone's location (a bit like range gate stealing).

Remember that in order to force the drone down you would then have to move it’s reported position a couple of hundred miles _relative_ to it’s proposed landing site, and you have no guarantee that the drone will be programmed to land at the same site it took off from.

Another consideration is what would the drone be programmed to do if its GPS position suddenly shifted a couple of hundred miles, I know I would build in some sort of cross reference between the INS and the GPS to ensure the two system are in agreement with each other.

All in all, the GPS spoofing attack seems highly unlikely, I suspect that some other attack vector was used to bring down the drone and the GPS story is just FUD.

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In fact as I am typing this I recall several incidents where commercial aircraft suddenly departed from their planned route because one of the pile-its in cockpit programmed the INS with the wrong waypoint coordinates.

Tech-grunt: "bomb ayatollah assahola airfield, sorry I though you said land ayatollah assahola airfield"

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Devil

Rock the Casbah!

This entire drone loss/capture thing has been quite interesting

The U.S. are playing it down, whilst the Republican Guard use it as a mighty propaganda tool.

I wouldn't be surprised if the Iranians did cause it to crash with some sort of jamming device, they're a fairly canny bunch and quite self sufficient militarily.

Due to sanctions the Iranians have had to develop a lot of home brewed tech (A little like South Africa during the Apartheid / Sanctions era) however we know the Iranians do get more than a little help from the Russians and Chinese in respect to military technology, as long as it doesn't break the UN sanction laws.

Needless to say the Russians and Chinese are probably jumping up and down to get a look at the RQ-170 "if" it's genuine.

Looking at the drone on the video, it's hard to make out whether it's genuine or not, however a lot of sceptics claim that the drone on display is a fake. One comment I recall was it "looks like a carnival float"

One site I visited had extracted decent resolution pics from the HD video of the Iranians showing the drone off.

Notable observations were the fact that the wings swoop the wrong way, the video seemed to been filmed in a gym (wooden floors, high windows and small double doors in the video) and also that the top access panel seemed to have been "drawn with a sharpie" or marking pen as we know them.

But the most noted observation was the condition of the craft itself. Remarkably good indeed, although there was signs of scraping along the leading wing edges and tape on the wing joints, where some believe the wings may have been shorn off in the "crash", or perhaps removed to fit the RQ-170 into the building where it was filmed.

Lastly why did the Iranians go to such lengths to conceal the underside of their captured prize?

On the tech side, the RQ-170 is not a new aircraft, from what I've read it's been in use for a number of years, so it's not as if the Ayatollah's men are in possession of something that is blazing with the latest U.S. technology, or are the Pentagon trying to water down the importance of their drone?

.

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Alert

If it's a fake?

A couple of points come to mind,

Why would the US ask for it back and not just say it's a con job?

How are you sure the high resolution pictures proving this were not themselves faked?

Just a thought

شب بخیر

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Boffin

@Paul Johnston

Don't confuse people with logic, it always ends badly.

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Silver badge
FAIL

RE: Rock the Casbah!

"......they're a fairly canny bunch and quite self sufficient militarily....." No, they're anything but. When it comes to tech, they are just into copying or modifying old tech or buying it in from Russia, China or North Korea. All their much-hyped "developments" are obvious jokes to anyone with a clue.

The perfect example is the Iranian "Saequeh" jet fighter, which is very obvioulsy just an old Northrop F-5A with the single-fin replaced with twin-fins. The F-5A was designed in the '50s for the US military aid program, and was deliberately limited in capability to give friendly Third World countries a barley supersonic fighter that was capable of reasonable air-def, without giving them the strike ability to threaten neighbours with. It has been ridiculed as "having the range to carry a matchbox the length of a football field", yet the Iranians claim their Saequeh has a mission range of "3000km" and can match the ability of an F/A-18! F-22 pilots should have no trouble clearing them from the skies.

Their indigenous MBT, the Zulfiqar, is nothing more than a hodge-podge of old US M-60 and Soviet T-72 parts, neither being tanks of particular note and definately not viable on the modern battlefield. The fire control system is also an import from Slovenia and about twenty years behind NATO designs. In a fight against even the 90's tanks that kicked Saddam out of Kuwait, the Iranian tanks would be cannonfodder. Against modern NATO tanks they would be little more than target practice.

Their missiles are all imports - the Shahab ballistic missile family they hope to put a nuke tip on is nothing more than a licensed copy of the North Korean Rodong 1, and they had the Norks set up their missile factories for them. The Rodong in turn is just a developed copy of the ancient Soviet SS-1 Scud. The Fajr missile the Iranians claim has MIRVs with radar-avoiding technology has never been seen to launch successfully, let alone deliver MIRVs, and is again a copy of Soviet '60s tech sold to Iran by the Chinese.

Iranian drone tech? Their best would be the Karrar, another hodge-podge of Western and Soviet tech in a frame copied from the MQM-107 target drone from the '70s. Again, the Iranians have made many wild claims for capability but have never demonstrated any of them. At best, the Karrar would provide amusement for NATO interceptors and SAMs. Other Iranian drones include the Ababil, a poor copy of the Predator, only with less than half the capability. Of the three Ababil drones launched by Hezbollah all three were shot down by the Israelis in short order. The Iranians did attempt an Abibal flight into Iraq in 2009, but it was shot down by an F-16. The other "mass-produced" Iranian drone is the Mohajer, a toy that has only been recorded making an operational flight once, when one was flown into Israel by Hezbollah, but crashed into the sea before the Israelis could shoot it down, so hardly a success story.

The Iranians like putting out propaganda about amazing Iranian military developments, but they all prove to be nothing more than copies and old tech. A perfect example of this blatent lying is the Hoot "supertorpedo", which is just a copy of the Soviet VA-111 Shkval, again more 60's/70's tech. The Iranians flatly refuse to admit it is a copy, even though Russian experts have pointed out design points that could only have come from the Shkvall. This propaganda has two purposes - to fool the Iranians into thinking they have a technologically capable and proficient economy, and for fodder for those in the West that want to believe.

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Bronze badge

The whole story doesn't make sense

Ive been thinking the same thing since we handed them, erm excuse me "lost" this "RQ-170". They base the RQ-170 out of the place the mainstream press refers to as "Area 52" because the security and secrecy around that facility and the 3rd Reconnaissance Squadron which operates from there is about the same as Area 51 was before World+Dog found out about it.

Because of the circumstances surrounding the RQ-170 and Sentinel project, I find it very hard to believe that we just let one of these things fall into enemy hands. The US Air Force has been known to bomb crashed secretly configured Aircraft in places that said bombing was very likely to have repercussions, like Laos and Cambodia before Vietnam expanded.

It just sounds an awful lot like a deception operation in the same vein as Operation Mincemeat during World War II. We give the enemy a ruse and let them think its the real thing so they wont believe it when they actually do find something later.

http://en.wikipedia.org/wiki/Operation_Mincemeat

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Meh

Hrm...

>Why would the US ask for it back and not just say it's a con job?

Didn't the US report a UAV lost to a malfunction? Even if the video is faked to make Iran look like super hax0rs, there's still the matter of the *actual* wrecked drone.

I thought most drones had pilots flying them remotely, shouldn't someone have noticed one of them drifting off course and given it a destruct signal of some sort?

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Facepalm

Ofcourse its "rubbish"

Because if you say it isn't rubbish you're basically admitting "defeat" and we can't have that, can we?

Learned absolutely nothing here. Same as in Iraq and Afghanistan when locals (for crying out loud) shared stories how they managed to bring down aircrafts and helicopters. "Nonsense", the boffins said deeming it "impossible" and then the pictures came out.

The first situation (not ridiculing it right away) could have some negative effects (morale perhaps?) but then again most people and countries realize that they're not invincible nor immortal. So I'd say its neglectable.

The second scenario on the other hand seems much worse to me. Experts and such are totally convinced that the news is fake and use strong words to brush it all away. And then it turns out to be true.

Maybe I'm seeing things a bit too simplistic, but to me it makes those "experts" look like a bunch of idiots right then and there. And I'd immediately start to question every other thing coming out of their mouth.

Personally I think that scenario is much more damaging; it doesn't necessarily affect morale (perse) but sure puts dents in ones credibility. And sometimes that's just what you need to keep morale up.

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Silver badge

Counter rotating spin machines

The quoted document is correct in that it's very hard to spoof GPS in such a manner that you can undetectably take over a genuine GPS signal and shift it without anyone being able to tell - as in a Bond movie plot.

Simply sending a fake GPS position is trivial - we rent a test range to test our equipment that can generate a GPS position to be anywhere on earth (they tend to be very careful about not having the signal leak out!)

The drones do have an IMU in addition to the GPS - it's very difficult to land if you don't know pitch/roll/yaw - but they drift and so you update them from the GPS. You can put a super duper accurate IMU but it's expensive and is exactly the sort of tech you don't want the otherside to get their hands on when you do inevitably lose one. For the same reason this only has fisher-price levels of stealth.

There are a couple of reasons for not putting a massive self-destruct charge onboard triggered whenever it loses GPS. One is that effect on the life expectancy of USAF squaddies servicing it, the other is that it does tend to look a wee bit threatening. If a 'peacefull' Iranian drone exploded over the London olympics because it lost GPS that might result in slightly more than a letter to the Telegraph.

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Thumb Up

Interesting supposition that it is essential to prevent the drone losing GPS lock, as if there were a human on board who would think "that's strange, before we lost lock we were 14 miles from the coast of China, now it says we're 20 miles" (*)

Setting aside that it probably was incompetence, if an "attack" were to be made then It may well be enough to *force* a GPS loss-of-lock with any old jamming and then broadcast a fake Ephemeris at a higher strength than the actual signal.

If the receiver has not been programmed appropriately with how to handle a temporary loss of lock, it would happily start using the "reacquired" spoof signal and never know ...

Oh, by the way, I was under the impression that the military signal *was* encrypted, which lends credence to the "incompetence not conspiracy" angle.

(*) That was the plot of the Tomorrow Never Dies Bond film ... GPS spoofing by hacking the receiver itself I think ...

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Anonymous Coward

There are a number of reasons to use drone surveillance aircraft; one of those reasons is that they are relatively expendable. I would hope that the military wouldn't put highly classified equipment in a drone for the simple reason is that they are susceptible to being lost and captured -- they were designed so that nobody would cry over a lost drone.

Whether the item that the Iranians have been crowing about is an actual US drone or not probably makes little difference. If it is a real drone, the US now knows that they have a vulnerability that needs to be remediated. If the Iranians did spoof the GPS, whatever security classification the navigation equipment may have had was compromised before it was lost.

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MrT
Bronze badge

Interesting tactic...

...flood the area around a highly sensitive potential/likely target for, perhaps, cruise missile attack with the spoofed GPS signature of a US airbase miles away. Missile won't commit blue on blue, and comms will likely be disrupted, so cruise will loiter whilst other on-board systems (visual etc) confirm target area, by which time the thing has probably been taken out by SAM.

Lobbing dumb iron on a ballistic trajectory would be an option I suppose - bring on the rail guns!

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Silver badge

THERE IS A SIMPLE EXPLAINATION.....

Sgt Duffer and His ground crew forgot to top up the fuel tank. It ran out of super unleaded.

Sgt Duffer is now a private stationed in Alaska. You wouldn't want to admit to that error would you.

It's so simple it is painful.

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You have to assume that they'd have some sort of fuel level sensor, however being as that it's maintained by Sgt Duffer's mate, who was drunk at the time, it's perfectly possible it was broken...

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Sgt Duffer may have forgotten to top up the tanks but it would be Lt McDufferson flying the bird and ultimately responsible.

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Black Helicopters

"Experts"?

Uh-huh.

Translation: "Doubts that Iran managed to bring down an advanced US drone over the country last month using an advanced GPS spoofing attack have been injected into the mainstream media by US government-led propagandists, in a damage limitations exercise (a.k.a. the "war of perception").

Conspiracy theory?

Think again:

{quote}

A secret CIA report, brought to light last month by Wikileaks, reveals the cynical battle plans for the "war of perception" being waged over public opinion in Europe about NATO's war in Afghanistan. The four-page document is well worth reading, mainly to see exactly how cyncial the powers-that-be are when assessing the public.

The report's subheadings tell the story: 'Public Apathy Enables Leaders To Ignore Voters ... But Casulaties Could Precipitate Backlash', 'Tailoring Messaging Could Forestall of At Least Contain Backlash', 'Appeals by President Obama and Afghan Women Might Gain Traction'.

{/quote}

http://rabble.ca/blogs/bloggers/derrick/2010/04/wikileaks-cia-recommends-france-use-afghan-womens-rights-boost-war

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FAIL

Sure the CIA wrote it ...

... but don't you support womens right in Afghan anyway? Or is it the case that, because supporting womens rights means supporting NATO operations in Afghan, the correct attitude is "sod the women"?

This is unfortunately the case with a lot of the Stop the War lot ... NATO is inherently bad, so anyone who opposes them is naturally good, so yay Taliban!

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Back in the days

when I was in the german navy, we weren't allowed to track Tornados with our WM25 Fire Control System. (Mk. 92 in the US on the Perry Class frigates) because one was lost due to electronics malfunction when hit by the pulse.

I do think that there are ways to down a drone short of GPS jamming, just use some very high powered land based STIR like Radar and burn out it's brains.

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Thumb Up

And satellites are usually located *above* the aircraft

while spoofer transmitters are almost always (unless airborne) located below it. I suspect the drone's GPS antenna pattern is optimized for reception of satellites, rather than ground transmitters...

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Flat spin = unscathed? (even relatively!)

Hmm not sure about a flat spin leaving you unscathed once you hit. Your rate of descent in a spin is still far in excess of anything you would ever want to approach a solid object at. Have done one of these in a Chippy and the VSI was down against the stops (300 fpm), even though it didn't feel like it.

Any real pilots care to comment?

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Flat spins have a lower descent rate than than a 'normal' spin, but I wouldn't know by how much. My gliding club requires that I spin a glider for recovery practise at least once a year, but I have never been in a flat spin and hope I never am: they are much more difficult to recover from.

The only aircraft I've seen in a flat spin, using only my Mk1 eyeball to observe it, has been an F1A class model glider, which are deliberately spun to get them down out of the thermal at the end of a flight. I've seen these go into a flat spin many times when the spin settings are not quite right. As it transitions from a 'normal' spin to a flat spin its descent rate is reduced a lot while the rotation rate increases dramatically. After a short while the flat spin destabilises and becomes a violent tumble which may, if you're lucky, transition back into a normal spin. The tumbling descent rate is a lot higher than during the initial spin, and if its tumbling when it hits the ground you get a lot of damage.

Flat spins, etc. may well do more damage on impact than normal spins because the rotation speed is so much higher.

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Pint

Trojan Drone

aka 21st century Trojan Horse.

http://en.wikipedia.org/wiki/Trojan_Horse

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Gold badge
Boffin

How it *might* be done.

For starters you'd need a radio base *above* the drone (It's GPS aerial/s are likely above the fuselage for best access to the sky). Note the receiver power levels (IIRC -160dBmw, that's about 2^53 below the reference power level) so "swamping" it from say a couple of Km above it is not going to take too much *real* power. Think car battery, not truck engine.

Switch on the jamming and cut off the drone from GPS reception.

Switch on the GPS simulator channels (You'll need at least 4 of them, on 2 channels) with a position *plausibly* close to where the drone thinks it is (from its internal IMU package) and start walking.

Note the initial data string, tap positions and shift register length for the military code have (AFAIK) *never* been published. It has been stated (in the USG design docs) that each satellite uses a different section (IE different point in the sequence) of the *same* code with the same taps. The code per satellite repeats over roughly 1 week at 10.24MHz and is roughly 1/10 of the full capacity of the shift register generator. You have to think in terms of early 1970s TTL chips. Calculating its likely length is none of my business.

The military code *can* be encrypted but I'm not sure how often it is (like Selective Availability for the C/A code it is *optional*). There is at least one paper in the open literature about it but the USG has never officially released it. Give how widespread GPS is the key is likely to be transmitted in the more frequently repeated parts of the 300 bit frames that make up the full 12.5min GPS data stream, allowing potential lock up in 6 secs rather than 12.5 (which is a *long* time in guided weapons).

With fast enough logic it might not even be necessary to have your own atomic clock. Use the *real* GPS stream to work out your position, calculate the numeric offsets needed to push your target in the right direction and re-encode for for the drone to receive it.

In an era of GHz logic a country with sufficient resources could get something like this made on a reasonable budget in the way the EFF finally built a DES cracker to *prove* once and for all DES was no longer secure. A fairly modest 2Ghz processor could run 200 instructions to process each bit sent.

Easier than just shooting it down or jamming the GPS and hoping it goes into some sort of emergency landing safe mode. No.

Within the financial and intellectual resources of a nation state with a substantial oil revenue. Definitely.

It was said no way could Afghanistani Jihadists read drone video (despite it not being encrypted). This proved incorrect.

Sun Tzu noted that those that show contempt for their enemies are likely to underestimate them until they ultimately loose.

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"...conceding it was carrying out a covert spy operation over Iran. The US has asked for the return of the drone..."

Love that tactic - just like when the Iraq war was being staged, when the "Allies" asked to allow spyplanes fly over Iraq - definitely not finding the tanks, artillery and stuff. :)

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Mindless speculation

The Iranians transmit some kind of gibberish at the command channel of the drone. Something trips a bug, and the computer resets. When the computer restarts, it thinks "FUCK! What's going on!" and promptly lands.

Easy!

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FAIL

Let's underestimate the opposition again!

So... By its own admission the US lost a spy drone over Iran.... but continues to make the Iranians out to be technologically incompetent despite their recognised successes in satellite launching, stem cell research etc etc.

Might be good enough for people who don't want to think, but it's not an attitude that will be very helpful going forwards.

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Bronze badge

Indeed

All it takes it the combination of a lot of clever hard-working and well-motivated Iranians, prolonged and repeated drone incursions, some unknown vulnerabilities in the drone systems, and a bit of good luck.

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Childcatcher

What about Iran's BFF?

Russia.

" Moscow also wants to improve diplomatic and military ties with some of Iran’s rivals. The Russian Ministry of Defense is interested in purchasing sophisticated weapons from abroad that its arms industry either does not produce or produces poorly. IT HAS ALREADY BEGUN BUYING UNMANNED AERIAL VEHICLES FROM ISRAEL." (2010)

Just sayin'.

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Stop

Can we stop the BS

So the CSM says "someone told us something" and some people say it's not true. Did the Iranians ever mention GPS spoofing? NO, how about the US? NO. All we have is someone claiming to have spoken to some Iranian dude in a pub.

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Bronze badge

You're just not thinking fourth-dimensionally...

Love that quote.

I have a nasty mind, so it came up with this scenario:

General: We know Iran has boffins in a secret lab near this area. How do we find this lab?

Corporal: Sir, we could "lose" a seemingly high-tech piece of technology in the target zone and track it to see where it's taken.

General: What do you propose?

Corporal: Gut one of our spy planes from anything we don't want them to have, fill it with useless but interesting-looking tech, and have it develop a "fault" over Iran - a leaky fuel tank should do it.

General: But would they fall for it?

Corporal: If we go on record to say the Drone is not worth anything but proceed to ask for it back via the usual channels, yessir I think it would.

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Look here, don't look there

Another possibility is that they wanted to keep the Iranians looking in one direction while something else happened nearby. Maybe somebody wanted to get some people in or out of a sensitive area in Iran and needed a diversion.

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Silver badge
FAIL

The more important thing is China and Russia have ...

a working, almost undamaged drone with some of the most sophisticated sensors on board now sits in Tehran.

Regardless of whether a desk-bound pilot or some Russian jamming equipment brought it down, it is Iranian hands and will likely be made available to the highest bidder. Likely something to advance their nuclear ambitions.

I saw reports that over 30 drones have crashed in the past two years which demonstrates a systemic weakness.

The U.S. is embarrassed over this loss and no doubt much of the chatter is an attempt to play down the significance of this loss and therefore is as reliable as Iranian claims.

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JMB

Drones seem to fly mainly in level flight so won't the GPS antenna be directional to pick up signals from above. They could even incorporate a simple test for stronger signals from below which would indicate jamming and interference.

I wonder if one crashed (presumably innards would self-destruct) and the iranians used the wreckage to make a replica?

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