Look at these weird turboprop N1 gauges:
I'm referring to the smaller needle at the top of each
PERCENT RPM labelled N1 gauge. What does it display ? I have no idea.
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It duplicates the percent graduations in the large dial but at a finer resolution, with one percent increments. It's just to make the individual percent graduations easier to discern at a glance without having to squint down at the gauge to judge where the needle's point is relative to the little hash marks, which are in 2 percent increments.
When the big dial moves from 0 to 10%, the small dial makes one full rotation. So when the big dial needle is at 5, or 15, or 25 etc, the small dial will also be at 5 (6 O'clock).
You can watch it in action here at about 1:25.
If the engine is at 95% RPM, the large needle will point halfway between the "90" and the "100" indication on the outer scale, and the needle on the small dial will point to the "5" mark on that dial.
The smaller dial makes it easier to read an exact RPM, to a precision of about +/- half a percent.