Instrument Flight
Constant Airspeed Climbs and Descents
CONSTANT AIRSPEED CLIMBS AND DESCENTS
Constant airspeed climbs and descents will introduce you to the principle that changing the aircraft nose
attitude (pitch) is the primary method of controlling airspeed when your aircraft is climbing or descending.
Thus, the critical and challenging component of these maneuvers lies in establishing a pitch angle that
results in a climb or descent with little or no change in airspeed. You will use constant airspeed climbs
during departure and constant airspeed descents for cruise and penetration descents.
Because you are using nose attitude (pitch) to maintain airspeed during these maneuvers, the primary
instruments to scan are the ADI display for pitch and bank control and airspeed for performance. You will
need to start picking up the altitude trend wiper blade in your scan as the maneuver progresses so that
you can identify the point at which you’ll transition to level flight. VSI indications are instantaneous, so
avoid making abrupt adjustments or you will find yourself chasing it. Your scan should center on the ADI
display ball and the altitude trend wiper blade during the period from lead point to assigned altitude
because you will be trying to arrive at a pitch attitude that represents level flight at the same time you
reach your altitude. To perform a smooth level off at the correct speed, you will always need to start your
transition to level flight by coordinating power and nose attitude.
CONSTANT AIRSPEED CLIMB
When beginning at normal cruise airspeed, maintain heading and advance the throttle to MRT.
Simultaneously establish a noseup attitude of 8 to 10 degrees on the ADI display to maintain 250 KIAS.
During the climb, use small nose attitude changes to maintain airspeed. Trim as necessary during the
climb to maintain a very light feel on the stick. Use the ADI display ball (for pitch and bank control) and
airspeed and airspeed trend wiper blade (for airspeed information) during the entry and to maintain the
climb. An occasional glance at the altitude and altitude trend wiper blade during the climb will let you
know when you are nearing the lead point, at which time you’ll incorporate the altitude fully into your scan.
When the aircraft reaches a lead point of 10 percent of VSI (for example, if the climb rate is 3,000 fpm,
initiate the level off 300 ft prior to reaching the desired altitude), simultaneously reduce power to cruise
and set nose attitude to maintain level flight. You should scan the ADI display and altitude trend wiper
blade during the period, with occasional checks of airspeed from lead point to altitude, because you will be
trying to arrive at a pitch attitude that represents level flight at the same time you reach the altitude. Once
you are established in level flight, retrim the aircraft.
Constant airspeed climb—normal cruise entry and exit:
Throttle: MRT
Pitch: Initially 8-10 degrees noseup to maintain 250 KIAS, then as required to maintain
airspeed. Beginning in RI stage, lower the nose to approximately 3 degrees and accelerate to
300 KIAS at 10,000 ft. Adjust nose and trim as necessary to maintain 300 KIAS climb until
intercepting 0.72 indicated Mach number (IMN). This occurs at approximately 25,000 ft.
Level off: Lead by 10 percent of VSI.
Throttle: Cruise (see table of cruise airspeeds and fuel flows in INSTRUMENT FLIGHT
PLANNING). For BI stage, maintain 250 KIAS in the climb. Plan to level at 250 KIAS at an
altitude specified by your instructor. For level flight at 250 KIAS, set approximately 1,200 pph
at 15,000 ft MSL.
Pitch: Adjust for level flight
Trim: Adjust for level flight
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