Originally posted by Freddie
The notes on that image are as follows (clockwise from top):

Текущий курс = Current course of the aircraft.

Директорные планки = Director cues (used for ILS approaches, the indicators with letters "K" (Курс) and "Г" (Глиссада) display the presence of valid localizer and glideslope signals respectively).

Курсовой угол на навигационный ориентир = Bearing of the current navigation point, i.e. if you fly your aircraft following this needle, you'll get to that navpoint by the shortest possible path (if no wind is present).

Указатель заданного курса = Selected course needle. This shows you the desired course to the current waypoint that you have set in your flightplan.

If the navpoint bearing needle is aligned with the selected course needle, then you're on the desired course to the waypoint. Without wind, when both needles are aligned with the aircraft's course mark, then you're flying towards waypoint using the desired course. These needles will not be aligned with the aircraft's current course mark if you're flying in a crosswind. The angular difference between the aircraft's course and the aligned needles will show your crab angle or "угол упреждения" (lead angle).

A simple way to survive navigation in Su-25 is to write down a flightplan and then use the trick described by Foxbat to reset your current waypoint to no.1 if in doubt.

Hope this helps.
It sure does! Thanks!

Breadfan