GRUMMAN AMERICAN
FOR TRAINING USE ONLY – SECTION 4
MODEL GA-7/COUGAR
NORMAL PROCEDURES
4-21
Issued: April 10, 1978
During two engine climb, the mixture is normally left at FULL RICH below 5000 feet and adjusted for best power
mixture above 5000 feet. If the engine instruments are carefully monitored during the climb, it is also acceptable
to operate at best power mixture below 5000 feet.
For flight with one engine inoperative, the mixture should be leaned for best power.
During cruise flight, use of best power mixture is recommended for power settings from maximum power to 65%
power. For additional economy, best economy mixture may be used for all power settings of 75% power or below.
(Use of best economy mixture will result in a slight decrease in the cruise airspeed.) For power settings below 65%
power, best economy mixture is recommended.
During descent, the EGT should be monitored and maintained near peak EGT. Mixture must be enriched prior to
increasing the engine power.
STALLS
The airplane stall is normally elevator limited. Recovery from practice stalls at normal entry rates should be
initiated when the elevator has reached the full aft stick position. Recovery from accelerated entry or turning stalls
should be initiated when a nose down pitch occurs or the elevator control reaches the aft stop, whichever occurs
first. Onset of light to moderate tail buffet may occur at speeds between stall warning and the stall as described
above.
Maintain at least 5000 feet of terrain clearance when practicing stalls.
The loss of altitude during a power-off stall with gear and flaps retracted may be as much as 200 feet. The loss of
altitude with gear down and 30° of flaps may be as much as 200 feet.
The loss of altitude during a one-engine-inoperative stall with gear and flaps retracted may be as much as 300 feet,
a pitch-down angle as much as 20° and up to 25° roll. In the approach to a one engine inoperative stall maneuver,
it is not necessary to reduce the power on the operating engine in order to maintain lateral and directional control
until the stall occurs, except in extreme light weight conditions.
DESCENT
During descent, gradually enrich mixtures to maintain smooth engine operation. Descent should be gradual at
approximately 500 fpm at cruise speed, and with enough power to maintain the engine temperatures in the green
arc. Prolonged idle settings and low cylinder head temperature should be avoided. The recommended descent
speeds are up to 188 KIAS in smooth air, 160 KIAS in rough air, and 120 KIAS in turbulent air.
