MasterFlight See Peter King’s website, MasterFlight, for some great posts on IFR flying, Automation and more.
IFR “Know all” handout Great document with a lot of instrument flying information boiled down to a few pages. A must have for anyone working on an instrument rating.
Radio Comm Handout by AOPA
Single Pilot IFR (AOPA Safety Advisor)
IFR Communications: Serious Business – What you say and what you hear on the radio are more than mere words (Plane & Pilot Article)
IFR Radio A lot of great information on IFR communications plus links to much more information.
AC 61-98D Currency Requirements and Guidance for the Flight Review and Instrument Proficiency Check. UPDATED AC, dated 30 Apr 2018. This AC has a lot of new safety information, a MUST READ!
AC_91-74B Pilot Guide: Flight in Icing Conditions
Aircraft Icing Safety Advisor
AC 00-45H w/Change 1 Aviation Weather Services, dated 8 Jan 2018. Includes some important updates