[zdouglas]

A machinist I knew for an airline told me a story about how the avionics in plains in the late 80's could land autonomously in fair weather. The problem wasn't that the systems weren't smart enough, but that the tarmacs weren't robust enough to handle 'perfect' performance every time. After thousands of planes touched down within feet of each other, the pavement would crack and the systems couldn't be configured to inject variability to compensate.

[jdietrich]

There's a very similar problem in maritime navigation. Ships used to steer their course along shipping lanes by hand, but now they're automatically steered by GPS. Everyone is crowded right into the middle of the lane, greatly increasing the likelihood of collisions. After a fatal accident caused by this issue[1], the British Coastguard specifically instruct ships not to follow the exact line of the shipping lanes in the English channel.

[1] http://www.maib.gov.uk/cms_resources/SB_%202_2001_%20Ash_and...

[coob]

If this were true, then surely chucking a tiny bit of randomness in there would solve the issue.

[rogerbinns]

Planes have been able to land in poor visibility automatically since 1968 using the ILS (instrument landing system) radio waves. There are various categories with category 3 being supported in 1968 (low decision height and visibility).

Autoland systems: http://en.wikipedia.org/wiki/Autoland ILS Categories: http://en.wikipedia.org/wiki/Instrument_landing_system#ILS_c...