Regarding Flight 007 that got shot down in the Soviet Union, this was reported in the New York Times:

Study Says Korean Airliner Was on Its Intended Course When Downed in '83 (nytimes.com)


A retired airline navigator has gathered evidence that in his view shows that the South Korean airliner shot down over Russia in 1983 was on a deliberate flight path and did not stray accidentally into Soviet territory.

A principal part of his analysis is his refutation of what has been the prevailing theory, that the plane unintentionally flew off course because of a single-digit mistake in keying flight coordinates into the navigation system.

Leading aviation officials accept the refutation as correct, but still insist that the incursion was accidental and not deliberate.

We know this was a modern (at the time) Boeing 747 with a complex inertial flight management system.

No, I do not believe the theories about this being intentional. Nobody would risk a plane full of passengers like this on purpose.

In 1978 the KAL flight 978 went astray and was forced down on a frozen lake inside Russia.

Korean Air Lines jet forced down over Soviet Union - Apr 20, 1978 (history.com)

I would think this would be on their mind as they prepared for the flight.

So my question is: How did KAL 007 get so far off course?

Follow-up: Wouldn't they have noticed?

  • $\begingroup$ Is it possible the waypoints were entered incorrectly? Yes. Is it likely? Who knows? The incident has been the subject of an official report. Anything beyond that is speculation and thus off-topic. $\endgroup$ – user30849 May 16 '18 at 21:57
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    $\begingroup$ The NYTimes item you link to is an archival piece from 1992. I don't believe that's the currently accepted idea (which is that the autopilot was incorrectly set to follow a compass heading and not the programmed waypoints). $\endgroup$ – BowlOfRed May 16 '18 at 22:13
  • $\begingroup$ Also, electronics and interfaces have changed considerably from 1983. Modern airliners will have multiple changes in how they operate and are programmed compared to how it was done then. $\endgroup$ – BowlOfRed May 16 '18 at 22:58
  • $\begingroup$ The changes since then include GPS and all that, of course. I rode the first Alaska Airlines flight into Juneau that used GPS for landing. That was mid-90s. I just happened to be on it. And just happened to be sitting next to an AA manager. We talked all about it. Then, just before we landed a lady right in front of us pulled out her cellphone and made a call. He just laughed and said not to worry about it. It was a perfect landing. $\endgroup$ – SDsolar May 17 '18 at 4:02
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    $\begingroup$ The FMS was set properly. They likely believed it was in use and working. Unfortunately, it was not engaged. More waypoints would not have helped. $\endgroup$ – BowlOfRed May 17 '18 at 4:49

Chapter 4 of Degani's Taming HAL covers some of the details of this disaster, and is on a NASA site The Crash of Korean Air Lines Flight 007

It details some of the interface deficiencies in the aircraft's navigation selection system. We don't have definitive evidence about exactly what happened, but it is possible. It goes over the idea that it was easy to get the system in a mode where the pilots could easily have thought that the inertial navigation system was engaged, but actually wasn't.

The Mayday show covered this one as well. They noted that after the FDR was returned, it showed that the FMS was set properly. Even though it wasn't controlling the plane, it would have continued to show the waypoints being passed as the aircraft crossed to the side. Given that behavior, it would be very easy to believe that the system is working and you're where you should be.

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  • $\begingroup$ This makes a lot of sense. So even if it was set properly it wouldn't have helped. Accept. Yet the question still lingers about why they didn't notice. $\endgroup$ – SDsolar May 17 '18 at 15:24
  • $\begingroup$ @SDsolar as humans we miss things all the time. They saw the indications that told them it was working, as it always did, and felt no reason to monitor more closely. $\endgroup$ – fooot May 17 '18 at 15:48
  • $\begingroup$ Good point. You reminded me of JFK Jr. He didn't trust his instruments and ended up in a death spiral. $\endgroup$ – SDsolar May 17 '18 at 20:33

The believed fate of Flight 007 is that the autopilot was set to fly the compass heading instead of the INS (source: revised ICAO report). As for the likelihood of incorrectly entering waypoints; the way the procedure works is that the Captain would say the waypoints and the co-pilot would enter the coordinates in the INS. The co-pilot would then repeat the coordinates and the Captain would ensure the read-back was correct.

Under this system you would think that there would not be a mix-up as the captain and co-pilot would both verify the information. The biggest chance of a mistake would be if the coordinate was written down wrong. Such as what happened on Varig Flight 254.

Captain Garcez consulted the flight plan for the magnetic heading to Belém; the flight plan read 0270. Garcez interpreted this as 270 degrees, but the intended meaning was 027.0 degrees.

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  • $\begingroup$ I'm not a pilot, but it surprises me that neither pilots would know where they were going enough, at a situational awareness level, to know the difference between West and North-Northeast. But there you go! I suppose they fly around in so many directions on such a flight, and via so many intermediate points that you lose that kind of awareness. $\endgroup$ – Dan Sheppard May 17 '18 at 0:40
  • $\begingroup$ Thanks, @DLH, for that info about Flight 254. That is an error that makes some sense. $\endgroup$ – SDsolar May 17 '18 at 4:00
  • $\begingroup$ I did my flight training in Fairbanks, a bit north of Anchorage. The compass deviation was about 17 degrees. ngdc.noaa.gov/geomag-web/#declination - Then I would set it in the gyro compass before taking off. I gather that "compass" in this context must have been simply in reference to the take-off point departure direction. And I would presume that it would point towards the great-circle route to their destination. I am amazed that the error was so slight at takeoff that it wasn't noticed, yet with catastrophic results. $\endgroup$ – SDsolar May 17 '18 at 15:31

The theory that I dimly recall was that when a route was manually programmed using waypoints created from Lat/Long data, the crew SOP was they were supposed to enter the waypoint data in each FMS separately and compare the two resulting routes so that random key input errors were likely to show up. Instead, because they were in a rush, they entered the route in one FMS then copied it to the other and a keying error putting a waypoint 60nm west (or something like that) of where it was supposed to be went undetected.

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  • $\begingroup$ Being in a rush is what caused Challenger to blow up, so I can understand that. $\endgroup$ – SDsolar May 17 '18 at 3:59
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    $\begingroup$ @SDsolar "Being in a rush is what caused Challenger to blow up" Not really... (at least not entirely) $\endgroup$ – user May 17 '18 at 11:27
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    $\begingroup$ Yeah Challenger was really a complex situation of confirmation bias, denial, bending to pressure, and wishful thinking all rolled into one, resulting in breakdown of an entire engineering/operational checks and balances process. $\endgroup$ – John K May 17 '18 at 11:52
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    $\begingroup$ Point taken. That was not the entire reason for Challenger. In fact, it was really caused by the way they assessed risk factors, according to Feynman: science.ksc.nasa.gov/shuttle/missions/51-l/docs/… - but schedule pressure is what caused them to cut corners. My comment was really just saying that this is an understandable reason why they might be in a hurry even at the cost of using an unsafe method of programming the flight-management system. I wonder if they were just tired from too many hours on duty. $\endgroup$ – SDsolar May 17 '18 at 15:06
  • $\begingroup$ Yes. I've made FMS entry errors that went undetected when my capt and I reviewed the waypoints... because we were in a big rush. We were flying around in a big circle in a corporate jet (a pre-delivery test) and we left off a waypoint cutting off one of the corners of our polygon route. Instead of busting us, ATC was kind enough to offer us a revised clearance when the controller saw us turning to the next-after waypoint instead of the next one. My capt was doing the radios and he read back the revised clearance adding "and thank you very very much". $\endgroup$ – John K May 17 '18 at 15:36

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