GPS override

Hi,

Quite spooky alright.

I just talked to a guy ( ex Tanker deck Officer) about doing a delivery with me from UK or Europe to NZ. I asked him if he would like to come as I might need to make use of his celestial navigation skills if the GPS fell apart.

I guess if he reads this he will want paying, pity he knows the Skipper in the trial very well.

Spoofing, jamming or even position pull off of a GPS system is not as easy, as it might look like from this article. From what I have red and what I was told, this spoofing system must be fairly close to the receiving antenna system.

Somebody sitting with a Laptop somewhere on the coastline and pulling an oiltanker 20 or 30 NM off shore into an collision course is science fiction and only works in James Bond films.

The flight management system of an airline aircraft or business jet, for example, does not rely on GPS only. It automatically tunes all available NAV aids in the vicinity of the aircraft and relevant to the route. If the difference exceeds certain limits, the pilot gets a warning and is able to take corrective action. TCAS helps avoid mid air collisions. GPS approaches with precision approach minima are backed up with calibrating transmitters or beacons on the ground (Differential GPS). A modern multi channel differential GPS system with automatic correlation of ground based NAV aids could not be spoofed with this method.

Modern military flying systems have also backup methods and systems to verify the accuracy of the GPS position. The 3-dimensional groundmapping database stored in the system can be correlated with the radar altimeter (height above known position), the laser INS (inertial navigation system) and an ground mapping radar. I do not believe that a single cruise missile, L/GPS guided bomb or drohne will go bananas, just because a Taliban with his Laptop sits behind the corner.

Any reasonable skipper or navigation officer will not rely completely on only one source of navigation. Most if not all modern multifunction displays which display chart and radar data, will have a map overlay function. Even a 10 year old boy could could recognize an larger offset of radar returns and map data. Commercial ECDIS (Electronic Chart Display and Information System) do that automatically and even correlate water depth into the position find.

Having said all that, does not mean, that one could get asleep on the bridge or in the cockpit, watch a soccer game during navigation or have a party with pretty girls behind the bridge or in the cockpit of an aircraft. Safety is paramount and the guys / girls on watch or on the controls have to be alerted during their duty.

The biggest danger of inaccuracy of the GPS system is the GPS system itself. The system needs a certain amount of satellites in the orbit being active at a time. If some of the satellites fail due to age or other malfunctions, they will be replaced by airborne spairs. But NASA is not getting enough spares into space. There is the possibilty, that GPS might get unreliable in the future due to lack of satellites in the orbit.

Do not count on the full scale operation of the European (Galileo) or Russian (GLONASS) satellite navigation system in the near future. They both need much more time to get their act together.

B.T.W. The number one reason for mishaps with the use of GPS on light aircraft or pleasure boats is the "Direct to" button and the high accuracy of the GPS system when taking a buoy as a turn point and the AP hitting it exactly .

Video version

If you want to see the video segment that aired and didn't notice the link on the page from the article posted above, view it here - How vulnerable are airliners, boats to hacking? Some of it is shot on the bridge and the crew is interviewed.

You will probably have to sit through a short commercial first.

That video proofs exactly my statement. The spoofing transmitter was located on the yacht. Doing the same thing from larger distance seems to be not very realistic.

If you are using a single GPS as the only means of navigation and do not crosscheck its results with other means of position finding, should at least be concidered carelessness.

The GPS compass system on classed ships is backed up by a gyro compass, a fluxgate compass and last but not least the good old wiskey compass. A spoofing induced turn and going off track of the AP will be recognized by the ECDIS system and hopefully by the officer of the watch. As soon as the ships RADAR will have returns from landmarks, the offset of the returns from the map position will be noticed and the degradation of the GPS signal indicated (opening of the CEP circle for example?). The nav officer will be able to correct that offset by a manuell mapmatch. If the GPS info is concidered to bad for navigation, its info and input can be rejected and subsidized by other means of position finding.

Modern advanced civil and military integrated navigation (and targeting) systems have mathematic algorithms (Kalman filter) included, that permanently calculate for inherent errors or pull offs of specific nav sensors like gyro compasses or INS/IRS (Schuler pendulum).

How did the seafares and aviators in the good old days ever navigate the seven seas and the air without GPS ?

A laser inertial navigation system can not be externaly spoofed, unless you are able to manipulate the earth gravity. That would be an ultimate weapon, pull off and manipulate the isogones .

I would not say, that spoofing of the present (civil) GPS system is totally impossible. But given the fact, that GPS is only one means of navigation for professional navigation in the air or on the water, the result should not be that dramatic like demonstrated in this sensational journalism type report.

The biggest chaos such a spoofing system could result in, is the manipulation of the GPS controlled automatic movements on the large automated container terminals like here in Hamburg. These terminals would come to complete standstill.

As the GPS system is owned by the US Air Force, it reserves the right of unannounced changes and manipulation of this system (selective availability). Therefore any navigator of the world should be aware of the fact, that he has to live one day without this system in specific areas of the world for a specific time.

I've had more than a few clients who spend their helm time with their eyes glued to the chart plotter. It's a constant battle to get them to look outside. "automation addiction" is a good term for it. On my handheld Garmin I reserve one of the data boxes for accuracy. Wouldn't be a bad feature for all. Unfortunately with most there are too few data boxes and you have to scroll menues for things like accuracy, ETA, etc.

Never trust anything I used to run on straight auto pilot (off the GPS) letting it do all course corrections but with all the little boats and logs I found that I and who ever was on the bridge got lazy. I like to also run all equipment just to stay aware and familiar with operation of the equipment
So I use the auto pilot and manually with power steering to adjust course on the auto pilot to over lay on a pre planned course on the nav screen. But even with this I have encounter twice where a large underwater cable has locked the compass and turned the boat to follow the power line to shore Once where I had to disengage the pilot and correct manually and once for a short 30 degree turn where it then self connected
That's why they call it Navigation Aids
As for terrorists Who cares I am always watching

I do not think, that I am missing the point. You are correct, you can not crosscheck a GPS with a second GPS. If one is in error or has a large CEP, the other one will have the same problem. I am only saying that an intergrated navigation system (both at sea and in the air) is redundent because of its different nav sensors and other inputs. And no operator should rely on a single input for navigation.

The flight management systems of an airliner will have inputs from GPS, other navaids like VOR, ILS, DME, Marker Beacon, NDB, AHRS (Attitude-Heading-Reference-Sytem) and multiple air data computers. GPS is only one system of it and only one source of information. If the 777 pilot for example had his AP selected to Groundspeed hold (which is based on GPS data), than he might have gone below the minimum approach airspeed, which is based on the aircrafts stall speed at the actual landing weight plus a given safety factor. But the target speed indicator (FMS) and angle of attack indicator should have warrned him visually and by audio, because their input are air data sources. Plus the audio of the radar altimeter must have alerted him about being below glide path.

As far as I am informed, the pilot did a manual and visual (unbriefed) approach, got behind the aircraft (means, ignored all info and warnings given by the instruments because of stress and lack of proficiency) and had an early touchdown with far to high AOA (nose to high because of low speed), the tail of the aircraft broke off and the big bird got out of control during rollout. It is amazing, how docile airline aircrafts are. A combat jet will kill you, if you do the same thing.

I do not believe that a ship or an aircraft could be rerouted or taken largely off course, just by spoofing the GPS info. Jamming is possible from far distance, but in that case, there is no GPS signal at all and the operator is informed about the total loss of GPS signals.

But I agree with you, that little john may end up on a rock, if he drives his boat with his handheld Garmin through the night or thick fog without radar or any other means of navigation. And this even without spoofing, just by a large CEP because of poor reception.

My American instructor pilot (an old vietnam veteran F-105 pilot) always said to me: "Flying and navigating an aircraft is including all aids, even the forward looking pilot"

B.T.W. This is exactly the excuse, Schettino is waiting for. "I am not guilty, somebody has spoofed the ships GPS".

If you look at this picture, which was taken through the headup display of the aircraft during the approach, you might see the amount of info available to the pilot. Only one info in the lower lefthand corner (150 Kts GS) is GPS based.

more sources

A good overview is Satellite navigation - Wikipedia, the free encyclopedia

New GPS Receivers will (should) support GPS, GLONASS and GALILEO.
I can not imaging how to fake all this systems at one time. The positions can be checked against the Almanach data.

The gounding of an american drone in Iran was done with overwriting the GSP frequencies with noise (GPS dropout).

GALILEO has protected data streams for comercial users. I would pay for a saver navigation ;-) GALILEO will feed your old GPS receivers - don't worry.

There is also an explaining video available.

Spoofing on the High Seas - YouTube

This is a video of the same experiment with the spoofing transmitter located on the yacht. Not very realistic. Professional crews are not that stupid (normally ).

If you follow the old 1 in 60 rule and the spoofer would be able to distract a vessel 3 degrees of course. If this would not be recognized by any other sensor on board including the crew, the vessel would be 3 NM off track after a distance of 60 NM (5 hours at 12 Kts !!!). We are talking about open sea outside radar range and horizon of any fixed returns. Not a big deal. As soon as the vessels radar picks up land returns (we are taking about 72 NM, or 48 NM off shore), the integrated navigation system will react and at least alert somebody. There is no mid sea collision risk included, as the (M)ARPA system and AIS calculate collision courses by dead reckoning (constant bearing calculation, no GPS needed).

Transformed this situation to high altitude airline traffic, there is at first radar coverage by ground based ATC stations. They will inform the pilot about any deviations from course and altitude. In areas of no radar coverage (ocean), the seperation of aircraft is much larger. All commercial aircraft are TCAS equipped which is a system similar system to (M)ARPA and AIS and works without GPS.

Like Ju 52 said, as soon as the Galileo system is on the air at full scale, there will be much more redundency in satellite navigation and the system is much more precise and reliable, because it is commercially operated and owned and no military or governmental agency can play any kind of selective availability.

Dont worry, be happy !!! But do not go asleep on watch .

There is quite a bit more to it than that ...


Iran spy drone GPS hijack boasts: Rubbish, say experts ? The Register

This part of the article says it all. Thanks Marmot.

"According to our experiments, the attacker must ensure that his time offset to the system time is less than 75ns. Any greater offset will cause the GPS receiver to lose lock when the spoofing signal is turned on. A value of 75ns roughly corresponds to a distance of 22.5m, meaning that the attacker must know his distance from the victim with an accuracy of 22.5m (or better) — a higher offset will cause the victim to lose lock due to the signal (chip phase) misalignment.

We confirmed that the initial location offset will cause a noticeable jump of the victim’s reported position during the attack. Large offsets could therefore be detected by the victim by monitoring its position. Any imperfections in the arrival time of the signal from different antennas will directly impact the position calculated by the victim. If the relative time offset gets above 80ns, the signals will even cause the receiver to lose lock. This means that, if an attacker has multiple antennas, he must precisely know the distance from each antenna to the attacker in order to be able to spoof a desired location. We could also observe a general localization error as predicted in our theoretical analysis, even for smaller mismatches in the arrival times".

Then add into all this that Fox News isn't really news but more like the National Enquirer on TV so you'd have to take anything they spew with a grain of salt.

I think the grain of salt is seasoning for future funding of panic driven reseach grants. This whole tempest is so familiar ... the "missile gap" that never existed, the threat dejour that props up another layer of American defense contractor subsidies.

Why did the "researchers" feel the need to conduct the demonstration on a yacht in the med when they could have done exactly the same thing on a couple of rowboats in a pond near the school or while a couple of students walked around with backpacks?

This whole thing smacks of more pork for the "security" freaks.

Hi,

YYYYYYYYYYUUUUUUMMM, How will served?

With crackling and apple sauce is my favourite.

Exactly right.