Specifications

CESSNA SECTION 7
MODEL 172R NAV III AIRPLANE AND SYSTEM DESCRIPTION
GFC 700 AFCS
U.S.
ENGINE (Continued)
ENGINE INSTRUMENTS (Continued)
RPM (TACHOMETER)
Engine speed (RPM) is shown by the tachometer indicator found on all
EIS pages. The tachometer indicator uses a circular scale with moving
pointer and a digital value. The pointer moves through a range from 0
to 2700 RPM. The numerical RPM value is displayed in increments of
10 RPM in white numerals below the pointer.
The normal engine speed operating limit (top of green arc) is 2400
RPM. When engine speed is 2472 RPM or more, the pointer, digital
value, and label (RPM) turn red to show engine speed is more than the
limit. The digital value and label (RPM) will flash. The engine speed
(tachometer) is displayed in the same configuration and location on the
LEAN and SYSTEM pages. If engine speed becomes 2472 RPM or
more, while on the LEAN or SYSTEM page, the display will return to
the ENGINE page.
A speed sensor, mounted on the engine tachometer drive accessory
pad, provides a digital signal to the engine and airframe unit which
processes and outputs the RPM data to the EIS. A red X through the
RPM indicator shows the indicating system is inoperative.
(Continued Next Page)
172RPHBUS-00
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