Pluto Probe Almost Failed

Here is an article about the New Horizons spacecraft approaching Pluto three years ago.  Communication with the craft ceased three days before the flyby with Pluto!  Pffft!  They hit the panic button at mission control and called in the engineers to try to straighten this out with no time to spare.

http://nautil.us/issue/60/searches/how-nasas-mission-to-pluto-was-nearly-lost