The most current FAA Practical Test Standards in this series of handy cockpit-sized guides.
This is the reprint of FAA-S-8081-9C, Flight Instructor Instrument for Helicopter.
The PTS guide students, instructors, and FAA-designated examiners through checkrides.
Every PTS details the skill and knowledge that must be demonstrated before an examiner can issue a certificate or rating to an applicant.
Written by the FAA, these books list the knowledge and experience prerequisites, the levels of skill that must be demonstrated before an examiner can issue a certificate or rating to an applicant, and give the applicable background study and reference materials.