Commercial Chandelle Tips

5 Answers

1. 
   

   
   

   Nathan Parker on Aug 27, 2011

   Is isn’t, of course, possible to remain perfectly coordinated throughout the maneuver, but that’s a human flaw, not something the maneuver requires to be done successfully.
    
   Two keys to a successful turn-around, which works even if perfect coordination were possible:

   Make sure you’re very slow at the 90 degree point, which is aided by ensuring that your highest pitch attitude doesn’t come too early.
   Make sure you don’t gain airspeed too fast after the 90 degree point by controlling the nose as it drops toward the 135 degree point.

    
   Remember, rate of turn is maximized at slow airspeeds and high bank angles, so the slower you are at any given bank angle, the faster you will turn.

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2. 
   

   
   

   Bill Bradley on Aug 27, 2011

   Sounds good!  Great answer.  I’ll try and keep it slow and accurate!

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3. 
   

   
   

   Brian on Aug 27, 2011

   Hi Bill,
    
   One other thought to keep in mind is that rudder pressure will vary throughout the maneuver. Further, engine turning tendencies will aid in the need for pressure one way and be counter prodcutive in the other direction. Here, let’s examine the rudders when going left:
    

   Left (First 90) – Left rudder to enter the turn, as usual, and then neutral.
   Left (Through 90) – Right rudder very lightly added, progressively increasing as you’re airspeed slows.
   Left (Second 90) – The rollout, to the right, will require right rudder to overcome the adverse yaw from a right roll and a continued increase as airspeed slows further. 
   Left (Completion) – Up to this point right rudder is overcoming adverse yaw and engine turning tendencies. If done perfectly, you will actually very slightly reduce right rudder when you finish your roll out (no more adverse yaw), but still keep quite a bit in to overcome the engine turning tendencies.

    
   In short, turning left is: left rudder rolling in, neutral to first 90, gradual right rudder increase through 90, quicker increased right rudder through the rollout in the second 90, and a slight right decrease at the completion. 
    
   For brevity I’ll give you the short version to the right and let you analyze it on your own: right rudder rolling in, neutral rudder to first 90 and through the 90, lightly applied and gradually increased right rudder through the left rollout, and maximum right rudder with a sharp, but slight, increase just at the completion.
    
   As you can see it is quite a daunting task to really perfect the rudder dance required for this maneuver. The key to success is to shut down your bad boy 1000 and use your god given booty. Keep your butt centered in the seat and you’ll do just fine. Your body is more accurate, less flawed, and with a couple hours of practice I bet you’ll find that ball, when you turn it back on, on your g1000 to be better than you’ve seen it yet. To top it off you’ll feel more acomplished because you’ll quickly pick up a new skill. 

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4. 
   

   
   

   Scott Stahl on Aug 28, 2011

   One of the biggest keys to this maneuver is that the rudder pressure is NEVER constant.  Since you are constantly slowing throughout the maneuver, and thus your control effectiveness is constantly decreasing, you should be gradually increasing rudder throughout the entire 180 degree turn.  In the case of a chandelle to the left, including the initial roll in, you would start with the left rudder required to roll into the coordinated, and would gradually switch to right rudder as the turn is established.  Then as the airspeed decreases, you would continue to add right rudder througout the maneuver to counter the fairly pronounced left turning tendencies.  Since you are decelerating the airplane from nearly a cruise speed to just on the edge of the stall, there is a very prominent continuous, but smooth rudder change.
   The whole point of commercial maneuvers is not just actually executing them, but actually understanding the aerodynamic concepts behind the execution of them, which allows you to execute the smoothly and with timing that achieves the end goal.  While you may not be quite 100% coordinated through the whole maneuver, you should be very, very close.  Too many times, I see commercial students being taught to make the commercial maneuvers a very rote, very mechanical affair, and it just isn’t how it is intended.  They should be smooth, fluid, coordinated and timed properly.
   In regards to your question about the G1000, one thing I have learned about the G1000 is that the trapezoid (slip/skid) indicator is not very accurate with higher rates of roll or at higher rates of turn.  It was designed primarily to be accurate under instrument conditions, and it doesn’t seem to quite keep up at the higher rates associated with flying commercial maneuvers.  Your primary coordination information during these maneuvers almost has to come from the seat of your pants due to the G1000 limitations.  Where an old ball would never lie, the trapezoid has its limitations.  As long as you FEEL relatively coordinated in the seat of your airplane, then you are probably close enough.

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5. 
   

   
   

   Andy Neumann on Aug 29, 2011

   Bill,
    
   You are RIGHT ON about judging your coordination by the time it takes for the maneuver to be completed (rate of turn).  Judging from what you said in your original post, it sounds like you are over-correcting for left-turning tendencies.  Yes, you need to gradually increase right rudder as your airspeed bleeds off, but if you over do it, you will find that your left chandelle takes forever and your right chandelle happens too quickly. 
    
   Once the time it takes for the left chandelle and the right chandelle is equal, then you know you are in the “groove.”  Don’t worry too much about the ball–especially during the maneuver.  I might glance at it once at the end of the maneuver when I’m at the slowest airspeed.  Otherwise, this maneuver is a seat of the pants ordeal. 
    
   Best of luck on your checkride!

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