Today we use a suggestion field that is built against the title and redirect data. This field is used by the phrase suggester with a prefix length of 2. In other words if the typo appears in the first two characters all suggestions generated by the phrase suggester would be bad. Reducing the prefix length can hurt performances, another technique is to build a second suggestion field with a "reverse" filter.
We will have elastic 1.7.5 soon in production, I think it'd be nice to finish what we started on this task.
The top query for the last week of January 2016 was Terry Wigan which is certainly a typo to Terry Wogan (a radio and TV broadcaster who died this week).
I think that the reverse field would have helped in this case.