Definition and description of Chandelle

[jeaton01]

I think the Chandelle definition could use some clarification in the USSMA documents.  There is no mention of the transition that should occur at the 90 degree point, for instance.  As a start I have provided some excerpts from the FAA Commercial Pilot Practical Test Standards, the 1941 Civil Pilot Training Manual which was used in the WW II civil pilot training program, and from Modern Airmanship.  As will be seen, there is some variation but all agree with the current FAA standards in principle.  The reason I would like some refinement as it is a maneuver that seems to baffle a lot of contestants, and is not as easy to judge and critique as it might be with better definition.  It would also help those who study the USSMA documents refine their flying to have a more "concrete" description. 

I don't know how to insert a word file here so I will attach a link to the document on my web site.

http://yolo.net/~jeaton/USSMA/Chandelle.doc

I think the FAA definition with some modification would be a good starting point, certainly we don't want the maneuver starting at 1500'

[waconut]

John, Probably ALL maneuvers could use more clarification, but there is a commonality between AMA, Top Gun and USSMA in almost all identified/documented maneuvers What follows are the current rules for the Chandelle  across the 3 competition venues.
I think to use your source documentation for the Chandelle might just snowball into a total review/rewrite of all maneuver descriptions  The last maneuver description for the Chandelle is an excerpt from my Workshop for Learning US Scale Masters Flight Maneuvers" document.

As described in Top Gun & AMA:

CHANDELLE
This maneuver is an exaggerated climbing turn where the aircraft changes direction by  180 degrees. Depending on the type of aircraft performing the maneuver, the model may begin with a shallow dive to pick up speed. The nose should come up and the aircraft should complete a climbing turn, away from the flight line. Maximum climb and bank occur at approximately midpoint during the change in direction. Max bank angle may be from 45 to 60 degrees. Entry speed should be sufficient to prevent visible slipping or skidding and maintain the same turn rate throughout the maneuver. The degree of bank angle and rate of climb are constantly changing as the speed continues to decline through the maneuver.
As the 180 degree point is reached in the turn where the aircraft is traveling in the opposite direction from its entry, the wings are brought level for completion of the maneuver. At that time, the aircraft will be flying at quite a reduced speed as compared to its entry speed.
Errors:
Same turn rate not maintained. Aircraft skids or slips. The model does not establish a notable climb rate. Model does not finish with wings level on a heading opposite to that entered.

As described in the USSMA Competition Guide:

Chandelle: Any aircraft can perform this prototypical optional maneuver.
Described as an exaggerated climbing turn in which the airplane changes direction through 180-
degrees emerging at a higher altitude upon exit. The bank angle, speed, and rate of climb
depend upon the type of aircraft being flown. For example, a vintage aircraft may begin with a
shallow dive to pick up speed, the nose should then pull up and the model begins a steady
climbing turn proceeding away from the flight line. A high performance aircraft would enter the
maneuver from straight and level and exhibit a higher bank angle and rate of climb. Entry speed
should be sufficient to prevent visible slipping or skidding and maintain the same rate of turn
throughout the maneuver. The maximum bank angle may be 45 to 60 degrees for non-aerobatic
aircraft and up to 90 degrees for fully aerobatic aircraft. The degree of bank angle and rate of
climb are constantly changing as the speed continues to decline through the maneuver. When
the model has completed the 180-degree turn, the wings are leveled and the maneuver is called
complete. It is expected that the model would be flying at a reduced speed compared to entry.


As described in my "Workshop for Learning US Scale Masters Flight Maneuvers" document:
CHANDELLE
                                      (Document has a 2-dimension drawing of the maneuver inserted here)
   
This maneuver is an exaggerated climbing turn in which the airplane ch_anges direction through 180 deg emerging at a higher altitude upon exit.  The bank angle, speed, and rate of climb depend on the type of aircraft flown.  A non-aerobatic aircraft (vintage for one) may begin with a shallow dive to pick up speed, the nose should then pull up and the model begins a steady climbing turn proceeding away from the flight line.  A high performance aircraft would enter the maneuver from straight and level and exhibit a higher bank angle and rate of climb.   Entry speed should be sufficient to prevent visible slipping or skidding and maintain the same rate of turn throughout the maneuver.   The maximum bank angle may be 45 to 60 deg. for non-aerobatic aircraft and up to 90 deg. for fully aerobatic aircraft.  The degree of bank angle and rate of climb are constantly changing and the speed continues to decline throughout the maneuver.  When the model has completed the 180 deg. turn, the wings are leveled and the maneuver is called complete.

FAULTS:
1.  Turn not smooth and continuous
2.  Climb not smooth and continuous.
3.  Bank angle not appropriate for aircraft type.
4.  Start and finish not centered on judges' position.
5.  Final track not 180 deg. opposite to entry.
6.  Wings not level after completion of 180 deg. turn.
7.  Entry and exit not in straight and level flight.

/chuck

[jeaton01]

Chuck, the USSMA definition does not call out the transition at the 90 degrees of turn point, where the roll is reversal is begun.  

A chandelle as taught full scale is a transition from level flight to a climbing turn to the 90 degree point, from that point it is a transition back to level flight.   There is change on all axes throughout.  Power is added to maximum around the time the nose comes up through the horizon or soon thereafter.  An alternate definition is where the roll in to maximum bank occurs at the beginning of the pitch up and stays constant until the 90 degree point, but you will fail the current Commercial flight test if you do that one.

I bring up the subject because right after the split ess, this is the maneuver that most contestants don't understand.

Thanks for the AMA and Top Gun definitions.  

Maybe a backup document separate from the rules would be nice as a good description useful for teaching the maneuvers is too long for a rule book.  I think the contestants would enjoy having the best possible descriptions, more to learn and less of a feeling of shooting in the dark.

I don't want to be an irritant or know it all here, I know a lot of people have worked hard to get things as well done as they are now.  

Perhaps I will go out and do a few and make some notes.

John

[waconut]

John,

In the past few years, the Chandelle has given ground to a maneuver called a Climbing 180.
Pilots brief the judges on their execution of this maneuver, and seem to get approval/acceptance for its conduct.  Funny, but I can't find it described on any maneuver list (AMA-TG-USSMA).  Let's not go there....

In regards to your comment "Maybe a backup document separate from the rules would be nice as a good description useful for teaching the maneuvers is too long for a rule book. I think the contestants would enjoy having the best possible descriptions, more to learn and less of a feeling of shooting in the dark."

I have produced a document describing the scale maneuvers most often executed during USSMA contests namely entitled "A Descriptive Workshop for Understanding and Executing Scale Masters Flight Maneuvers.  Each maneuver is self contained and is comprised of a graph, a description of the maneuver and execution faults. This document is used in workshops that I have participated in.  In fact, the next workshop will be held at Hemet CA 4 Feb 2012.  You might want to take a look-see at this document.  It is available as a download –
http://usscalemasters.org/forums/index.php?action=tpmod;dl=item20

Note that this document is not approved by USSMA, but is made available as a "Competition Aide".  It is also listed in the Forum/ Flightline Chatter  first item: USSMA Flight Maneuvers Booklet Update.


Pertaining to your comment on the Split S, it's not that that the maneuver is not understood; it is almost never executed properly and usually gets a large downgrade by knowledgeable judges.
Hopefully, the maneuver critique portion of "my" workshops helps in proper execution of this (and others) as do maneuver demos.
/chuck

[jeaton01]

I printed that out a few days ago Chuck.    Lots of effort there!

A climbing 180?  Haven't seen that one yet.

John