Takeoff; Enroute Climb; Power Check; Wing Flap Settings - Cessna Hawk XP R172K Pilot Operating Handbook

SECTION 4
NORMAL PROCEDURES
CESSNA
MODEL R172K
SJ<;cTi~
NOHMAL PHOCI<;nURI-. •
An absence of RPM drop may be an indication of faulty grounding
of one side of the ignition system or should be cause for suspicion that
the magneto timing is set in advance of the setting specified.
ALTERNATOR CHECK
Prior to flight where verification of proper alternator and voltage
regulator operation is essential (such as night or instrument flights), a
positive verification can be made by loading the electrical system mo-
mentarily (3 to 5 seconds) with the landing light during the engine
runup (1800 RPM). The ammeter will remain within a needle width of
the initial reading if the alternator and voltage regulator are operating
properly.
TAKEOFF
('I(~ bv approximately 5 percent.
If 10° wing flaps are used for takeoff, they should be left down until
all obstacles are cleared and a safe flap retraction speed of 70 KIAS is
reached. To clear an obstacle with wing flaps 10°, an obstacle
clearance speed of 60 KIAS should be used.
. Soft field takeoffs can be performed with 15° flaps by lifting the
airpl ane off the ground as soon as practical in a slightly tail-low atti-
tude. If no obstacles are ahead, the airplane should be leveled off im-
~ediat~ly to accelerate to a safer climb speed. When departing a soft
f'ield with an aft c.g. loading, the elevator trim should be adjusted to-
wards the nose down direction to give comfortable control wheel forces
during the initial climb. Flap deflections greater than 15° are not ap-
proved for takeoff.
With wing flaps retracted and no obstructions ahead a takeoff
climb-out speed of 75-85 KIAS would be most efficient. '
CROSSWIND TAKEOFF
Takeoffs into strong crosswinds normally are performed with the
minimum flap setting necessary for the field length, to minimize the
drift angle immediately after takeoff. The airplane is accelerated to a
speed slightly higher than normal, then pulled off abruptly to prevent
possible settling back to the runway while drifting. When clear of the
ground, make a coordinated turn into the wind to correct for drift.
ENROUTE CLIMB
Normal climbs are performed at 85-95 KIAS with flaps up and
maximum power for the best combination of engine cooling, rate of
climb and forward visibility. The mixture should be leaned in
accordance with the fuel flow placard.
If it is necessary to climb rapidly to clear mountains or reach
favorable winds or better weather at high altitudes, the best rate-of-
climb speed should be used. This speed is 81 KIAS at sea level,
decreasing to 76 KIAS at 10,000 feet. Maximum power should be used
and the mixture should be leaned according to the fuel flow placard.
If an obstruction ahead requires a steep climb angle, a best angle-
of-?hmb sp~ed should be used with flaps up and maximum power.
ThIS speed IS 59 KIAS at sea level, increasing to 65 KIAS at 10,000 feet.
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POWER CHECK
It is important to check full-throttle engine operation early in the
takeoff run. Any sign of rough engine operation or sluggish engine
acceleration is good cause for discontinuing the takeoff.
Full-throttle runups over loose gravel are especially harmful to
propeller tips. When takeoffs must be made over a gravel surface, it is
very important that the throttle be advanced slowly. This allows the
airplane to start rolling before takeoff RPM is developed, and the grav-
el will be blown back of the propeller rather than pulled into it. When
unavoidable small dents appear in the propeller blades they should be
corrected immediately as described in Section 8 under Propeller Care.
For maximum engine power, the mixture should be adjusted during
the initial takeoff roll to the fuel flow corresponding to the field
elevation. (Refer to the fuel flow placard located adjacent to the fuel
flow indicator). The power increase is significant above 3000 feet and
this procedure should always be employed for field elevations greater
than 5000 feet above sea level.
After full throttle is applied, adjust the throttle friction lock clock-
wise to prevent the throttle from creeping back from a maximum power
position. Similar friction lock adjustment should be made as required
in other flight conditions to maintain a fixed throttle setting.
WING FLAP SETTINGS
Normal takeoffs are accomplished with wing flaps 0°_ 10°. Using
100 wing flaps reduces the ground run and total distance over an obsta-
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