[Taylor42]

I will ask. However, your statement assumes that the plane was off course one it's own. If my friend's story is true, I would not make that assumption. Maybe someone can tell us how "easy" or "not easy" it would be to influence an INS nav system with false signals.

[Alberta's Child]

You might also point this out:

If the intent was to kill one passenger, and they had no qualms about killing several hundred others in the process, and they had the means to fool around with the aircraft's navigation system, it would seem to me that having the plane crash in an "accident" would accomplish the same objective without drawing any attention to the Soviet Union at all.

[First_Salute]

Perhaps the biggest mistake, is to update the INS data enroute on the basis of dead reckoning that is itself not well thought out.

Judging from the flight path, that may exactly be what happened along with some deception by the North Koreans.

With two INS aboard, you might think to set one at the airfield of departure and then not mess with it. The other INS you might adjust enroute.

Then of course, you may wonder which is correct ... on up until radio reports of aircraft that you'd expect to be traveling on your route, indicate wx conditions not on your route.

At that moment, you might strongly tend to believe the INS readout that you left untouched.

What could have happened, is that the North Koreans resorted to make the appearance of being the ATC long-range radio stations (shortwave) and caused the crew to believe faulty time and distance information. A little "black box" aboard the aircraft, in the right place, could alter the signals so that the crew would be thinking that they were in contact with legitimate ATC's, when in fact they were in contact with the North Koreans, and nobody else heard a darned thing, except the VHF/UHF communications.

The North Koreans are notorious, in certain circles, for trying to "short sheet the bed" here, there, everywhere. They're real pranksters.

I suspect that the story above is essentially true, but a major mystery is in its failure to mention the shortwave radio comm's.

Apparently the crew did not mention shortwave radio failure.

It's just possible that the North Koreans deceived them into thinking that their shortwave comm's were normal.

[struwwelpeter]

how "easy" or "not easy" it would be to influence an INS nav system with false signals.

INS is preprogammed inertial navigation. You may be thinking of the radio compass which follows signals from radio beasons.

On September 2nd, 1958, an EC-130 was "lured" into Soviet air space by a technique known as "meaconing" (masking a beacon), and shot down with loss of the entire crew.

[Poohbah]

Maybe someone can tell us how "easy" or "not easy" it would be to influence an INS nav system with false signals.

You'd have to alter the strength of the Earth's gravity field.

[dozer7]

You would some how have to spoof it with a gravity-induced navigation error. It is a system that can not be simply jammed like a gps nav aid. As the configuration was triply redundant you would have to somehow tamper with all the sensors and do it in such a manner that at least two returned identical navigation data.

best regards

the dozer