the FAA 'Airworthiness Directive' in question(.pdf) ::
<a href="http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgad.nsf/0/828bbc426b0667298625807d00585f86/$FILE/2016-24-09.pdf" rel="nofollow">http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgad.nsf/...</a>