16.10 and 16.11 Piston engine indication systems and power plant installation

Scope

A level 1, B1/B3 level 2.

• 16.10 Indication: engine speed; cylinder head temperature; coolant temperature; oil pressure and temperature; exhaust gas temperature; fuel pressure and flow; manifold pressure.
• 16.11 Installation: firewalls, cowlings, acoustic panels, engine mounts, anti-vibration mounts, hoses, pipes, feeders, connectors, wiring looms, control cables and rods, lifting points and drains.

Instrument markings (light aircraft)

Marking	Meaning
Green arc	Normal operating range
Yellow arc	Caution / take-off or precautionary range
Red radial line	Maximum (or minimum) limit
Blue arc / radial	On some manifold-pressure or fuel-flow gauges — economy/cruise range (FAA mentions blue arcs on some gauges)
White slippage mark	Shows if the glass/bezel has rotated relative to the case

Engine speed (tachometer)

• Mechanical (magnetic drag-cup): flexible drive cable from the engine turns a magnet inside a drag cup restrained by a hairspring; also drives an hour meter (recording tachometer — "tach time").
• Electric: tacho-generator (three-phase AC; frequency drives a synchronous motor in the indicator) or electronic tachometers counting magneto P-lead pulses or crank sensor pulses.
• Red line = maximum rpm; some engines have a yellow (or red) band of restricted rpm due to propeller/crankshaft vibration — do not operate continuously in it.