User Guide

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What if it’s a real problem? Still “no
biggie:” the gear handle will already be
down. Slow the airplane to 90 knots or
less (to make it easier for the nose gear to
extend against the slipstream), then pull
the red emergency gear extension knob
just below and to the left of the normal
gear handle. Don’t be shy--it takes about
a 25-pound pull. This will dump the
hydraulic pressure holding the gear up,
and all three units will extend by gravity
(assisted by springs). Yaw the airplane
from side to side a couple of times to help
the main gear extend and lock. To restore the system to normal
operation, push the emergency control back in, and the gear can be
retracted normally.
PRESSURIZED CABIN
As you’ve seen, the landing gear system is as close to a “no-
brainer” as you’ll find on this airplane. The pressurization system
runs a close second. Although the idea of a pressurized cabin may
seem to be pretty heady stuff, it’s nowhere near as complex as it
was in the days of the great piston-powered airliners like the
Constellation, Stratocruiser, or DC-7.
Basically, high-pressure air supplied by the engine’s tur-
bochargers is first cooled, then fed into the cabin. The pressuriza-
tion system has no control (other than on and off) over the rate at
which this air enters the cabin; instead, it controls pressurization
and cabin altitude by regulating the rate at which the air flows
back out, through a pair of pneumatically controlled outflow
valves at the back of the cabin.
Most of the time, you’ll use only one control: the pressur-
ization controller on the instrument panel. Its outer ring of num-
bers indicates the altitude, in thousands of feet, at which the sys-
tem will attempt to maintain the cabin; the inner ring indicates the
highest airplane altitude at which the system can maintain that
cabin altitude. The knob at the lower left controls the rate at
which the cabin altitude climbs and descends; leaving it at about
the 9 o’clock position will provide your passengers with comfort-
able rates (no “ear popping”).
This can also simplify instrument flying. On a typical
approach using the instrument landing system (ILS), for example,
you’ll be flying level to the final approach fix, then descending
along the glideslope. If you have power set for level flight at a rea-
sonable approach speed with gear up and approach flaps extend-
ed, dropping the wheels at the final approach fix will give you just
about the right rate of descent with no additional power reduc-
tion--one less task at a time you’re already pretty busy!
You can also use the gear for drag if you need to get down
from high altitude in a hurry--for example, if you have a cabin
pressurization problem while cruising up in the 20,000-feet-and-
up range. (Bear in mind that the airplane’s oxygen system is only
good for 15 minutes of use.) You can extend the gear at any speed
up to 165 knots; but once it’s down and locked, you can go right
up to 195 knots, only 3 knots shy of the airplane’s 198-knot red-
line. At that speed, with the gear down, the Mirage will come
down like the proverbial greased piano.
When you select “down” on the gear handle, what happens
is essentially the reverse of the retraction sequence: the HYD
PUMP and GEAR WARN lights come on, and remain on until all
three green lights have illuminated to indicate that their respective
gears are down and locked (the downlocks are integral parts of
each wheel’s hydraulic actuator).
LANDING GEAR WARNINGS
The red GEAR WARN light will also illuminate, accompa-
nied by an annoying horn, to warn the pilot under certain cir-
cumstances: any time all three wheels aren’t down and locked
and either (a) the throttle is retarded below about 1/3 power, or (b)
the flaps are extended beyond 10 degrees.
LANDING GEAR MALFUNCTIONS
If you ever lower the gear and don’t see the reassuring glow
of “three greens,” don’t panic. In fact, as any experienced Piper
pilot will tell you, the first thing to check isn’t even part of the gear
system as such: it’s the panel light dimmer switches, below the con-
trol yoke. If the DAY/NIGHT switch happens to be in the NIGHT
position, the lights will be on--but so dim you can’t see them!
Flight Instruction
Flight Instruction
Emergency
Landing Gear
Handle