Sequences and Drills

Levelling Sequence

The levelling sequence will of course be used constantly during flights.  The clear target is to obtain the point of familiarity at which this sequence is completed without conscious effort.  Levelling requires that the pitch of the aircraft be placed with precision using the visual reference of the horizon (and or the attitude indicator when required, for example, owing to an obscured natural horizon)—the pitch placement will need the full attention of the left hand and the pilot’s visual reference.  It is the right hand that must complete quite independently the changes that are required in the aircraft’s flight configuration—power, propeller, mixture (if required) and cowl flaps.  It is therefore important that you be sufficiently proficient at the levelling drill so that the work of the right hand will not tax any mental effort.  When adjusting the power and propellers, rely initially on establishing the approximate physical position of the levers—then when you think you have set the manifold pressure correctly, for example, take just a quick peek to make the necessary fine tuning, or series of “quick peeks” as is required to get the instrument needles set correctly.  When setting the propellers, use your ears to initially set the approximate settings.

It is also useful to complete the settings of the power and propellers in two phases.  The first time you move across the power quadrant, aim to set only approximate settings—then, after the cowl flaps have been closed, return to power quadrant to “fine tune” the settings you require.  Here are the steps:

  • Place the aircraft in cruise attitude.
  • Set cruise power from left to right—setting manifold pressure, then propellers, and then mixture if required.
  • Close the cowl flaps.
  • Fine-turn the throttles, propellers, and mixtures as necessary.
  • Trimming should be conducted throughout.
  • Checklist if required.

Levelling Sequence—Circuits (Downwind Leg)

The levelling sequence in the downwind leg is quite different from the levelling sequence during normal cruise, and since students begin immediately to fly circuits, it is important to get this sequence mastered early.  An error commonly performed when turning downwind is to be slow at reducing power—when this occurs the aircraft typically begins to accelerate and this makes the management of pitch—and thus altitude control—very difficult and needlessly taxing of pilot attention.  Get to know the physical position of the throttle levers needed to produce 16”MP—it is quite amazing how far the levers have to be pulled back (very close to the engine idle settings).  Because the travel of the levers—the physical distance they must be moved—is so great, smoothness is critical.  This movement should not be done with the fingers or the wrists, but instead with the arm and a rigid wrist.  Remember that the MP indication will lag somewhat, so move the throttles sufficiently slowly to reduce this lag as much as possible.

Here is the levelling sequence for the downwind leg:

  • Place the aircraft in cruise attitude.
  • Set circuit power settings from left to right—setting manifold power at 16”MP, then propeller at 2400 RPM.  Leave Mixture at full rich.
  • Set 10° Flaps.
  • Close the cowl flaps.
  • Trimming should be conducted throughout.
  • Use of the Checklist is discouraged.

Climbing Sequence

  • Place the aircraft in climb attitude (approximately 5° pitch-up).1
  • Set climb power from right to left—setting the mixtures to full rich, setting the propellers to 2500 RPM, and then advancing the throttles to 25”MP.
  • Open the cowl flaps.
  • Fine-turn the throttles, propellers, and mixtures as required.
  • Trimming should be conducted throughout.

Engine Fire in Flight

  • Control the aircraft.
  • Fuel selector OFF on fired engine.
  • Shutdown fired engine—throttle smoothly closed, propeller smoothly but firmly set to the feathering indent, and the mixture set to idle cut-off.2
  • Seal off the firewall—both cabin heat and defrost selectors to OFF.
  • Then power up on the good engine, right to left, beginning with the mixture set full rich, the propeller set smoothly to maximum RPM, and then the throttle set to maximum power MP.
  • Take care of the good engine—if performance permits,3 set normal cruise power, beginning (left to right) with the throttle (24”MP), then the propeller (set 2400 RPM), and then the mixture (lean if required).4  
  • Take care of the bad engine—magnetos off, fuel pump off, alternator off, power-quadrant levers moved out of the way, cowl flap closed, fuel selector OFF.
  • Advise ATC of predicament, and request assistance.
  • Review checklist to ensure all items have been properly completed.

References

1. This pitch reference is just that—a reference point to initially place the aircraft’s attitude, but the exact pitch required will vary with the loading and weight of the aircraft.  As a rule, 5°-pitch will produce the desired 120 MPH cruise climb.  In contrast, after the takeoff rotation, 10° should be selected as this will approximately provide the desired 105 MPH (Vyse) with maximum power set.

2. As the shutting down of one engine progresses, be sure to keep the aircraft straight and level, incorporating the 5°-bank into the good engine.

3. Bear in mind here that the Service Ceiling for single engine operations is only 3650’ ASL (the Absolute Ceiling for single engine flight is optimistically published at 5000’ ASL at 4030 lbs. gross weight).  There may be times when normal power settings will not do owing to higher terrain, and that a reduction from maximum power is not an immediate option.  The power setting selected, however, affects the only remaining engine, and you may want to “nurse” it along with less strenuous normal power settings.

4. Consideration should be given to reducing the electrical load to preserve the remaining alternator—you don’t want an emergency such as this compounding into an electrical failure.

 

S