Getting on the step with a full power climb from below

Cirrus SR22TN Turbo, transition instructions from full power climb to cruise power, photo credit wikiWings
Cirrus SR22TN Turbo, transition instructions from full power climb to cruise power, photo credit wikiWings

Getting ‘on the step’ in a climb from below is easier with a Turbo Cirrus SR22 because the engine produces 100% full power all the way into the flight levels.  Pilot work-load is reduced because no mixture adjustments are required and there are no cowl flaps.  You just maintain full throttle and full mixture all the way up.

In a climb from below into cruise, you cannot always use the same procedure and get the same result.  Powering to best cruise speed can be affected by a number of variables; such as, airplane weight, balance, and density altitude.  Your time at full power may change if you have more fuel or an extra passenger or baggage in back (weight & balance) or hotter day (density altitude).

You’ll want to verify that the plane has accelerated to best cruise speed. For a piston aircraft capable in the flight levels, Knots True Airspeed (KTAS) is the acceleration indicator you should watch.  True Airspeed (KTAS) will continue to advance when Indicated Airspeed (KIAS) shows signs of losing pace.  Leave in full throttle and you’ll notice a subtle pitch lower of the nose and a better TAS.  On the Primary Flight Display, you’ll find TAS displayed at the bottom of the airspeed tape and IAS is at the center (refer to PFD picture below).

Cirrus Aircraft SR22TN Tornado Alley Turbo Operating Manual Supplement
1 Cruise Altitude Established Full Throttle
2 Power Lever 2700 RPM
3 Mixture Full Rich for 1 – 2 Minutes
4 Highest CHT Verify less than 380 degrees
5 Power Lever 2500 RPM at max available MAP 29.0″ – 29.6″
note: After initial power level setting to 2500 RPM, some additional MAP may be obtained by slightly increasing the power level until the RPM increases 10 – 20 RPM.
6 Electric Fuel Pump Low Boost
7 Mixture Full Rich – Smoothly reduce to cruise setting
note: Smoothly reduce fuel flow over period of 3 – 6 seconds to approximately 16.0 – 17.6 gph at 2500 RPM at max avaiable MAP (29.0″ – 29.6″).  During fuel flow reduction, a slight deceleration of aircraft will occur as the mixture passes from Rich of Peak TIT to Lean of Peak TIT.
8 Engine Parameters Monitor
note: If any CHT persistently exceeds 380 degrees F., then LEAN mixture further in 0.3 increments until all CHT’s are below 380 degrees F. (cont.)
Cirrus SR22TN Turbo, On the Step, 20,000 ft., 194 knots TAS, 75% power, FL200, photo credit wikiWings
Cirrus SR22TN Turbo, On the Step, 20,000 ft., 194 knots TAS, 75% power, 15.5 gph, FL200, photo credit wikiWings

Expert instructors say, a lot of pilots prematurely reduce power after leveling off before the airplane has had a chance to accelerate into normal cruise speed, which leaves the airplane established in a subtle form of mushing flight.

And, an improper cruise attitude or ‘mushing flight’ can exasperate higher cylinder head temps.  Full power and full rich mixture in level cruise for the proper length of time after a climb will help to lower cylinder head temperatures.

You should try life in a higher plane – Cirrus Turbo.

Reference: Tornado Alley Turbo operating manual supplement page 19 & 20. transitioncruisepower

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