Stunt Pattern for Intermediate, Advanced and Expert Classes 

Maneuvers shall be accomplished in the order listed below. The contestant shall notify the judges prior to the flight as to the specific maneuvers he wishes to omit in order that the judge will not be confused as to what maneuver to follow. Twenty-five flight pattern points shall be awarded a contestant who successfully completes the entire pattern as listed below. Each maneuver may be attempted only once. Not doing the correct number of consecutive maneuvers, doing less than two (2) laps between maneuvers, entering or exiting a maneuver in any way other than is illustrated in the maneuver section, and doing an incomplete maneuver all will result in a loss of pattern points. Omitting any maneuver, either intentionally or otherwise,or completing a maneuver out of its proper order shall result in loss of flight pattern points. A crash or failure to complete the pattern due to engine failure shall also result in loss of pattern points.Exceeding the eight (8) minute total elapsed time limit will cause loss of points on any maneuvers performed after the time limit, as well as loss of flight pattern points.

Description

Judges commentary

A correct takeoff consists of the model rolling smoothly along the ground for a distance of not less than 14.8 feet, but not greater than one quarter of a lap. The model then rises smoothly into the air with a gradual climb and a smooth leveloff to normal flight level over the point at which the model commenced its ground roll. The model continues on for two (2) smooth laps of normal level flight to point of original leveloff

The usual error is simply too quick a climb. Climbing to five (5) feet over the lap requires very careful attention. The climb rate is the essence of the maneuver. A slow and smooth climb rate to five (5) feet with good level flight merits a 38–40 since there is little else that can be done. Conversely, when the ship jumps off the ground, there is little left worthy of merit and the score should reflect this, i.e., a score in the 20s. Second, the two (2) level laps after the takeoff should have constant altitude. In windy weather, expect the plane to climb going into the wind, and lose altitude going downwind should the pilot get careless.

Correct reverse wingovers are judged when the model starts from normal flight level, makes a vertical climb and dive, passing directly over the flier’s head, cutting the ground circle in half, and recovers in an inverted position at normal flight level. The model continues for half a lap inverted, to the starting point, then makes a vertical climb and dive over the center of the circle from inverted flight, recovers at normal flight level. All turns to and from normal level flights shall be of approximately 4.9 feet radius.

The most difficult part of the maneuver is keeping the flight path in a straight line and going through the top of the circle. While nailing the first pullout is impressive, it should be noted that this is only a segment of the maneuver. Coming around for the second time, hitting the same starting point requires excellent timing. In other words, don’t be impressed with a good inverted pullout and ignore the wiggles across the top or missing the starting point by 10 feet on the return run.

Incidentally, the only good view of this maneuver is directly upwind. Consequently, if there are five (5) judges spread along the upwind side, several judges will get a decidedly poor view of the most difficult aspects of the maneuver and be hard pressed to evaluate the preceding. Judges may have to bunch closer together to get an adequ
ate view of this maneuver.

Correct loops are judged when the model starts from normal flight level and makes a series of three (3) smooth, round loops, all in the same place with the bottoms of the loops at normal flight level and the tops of the loops with the line(s) at 45 degrees elevation. The model then continues for another half loop, recovering inverted and descending to normal flight level, flying two (2) laps before being judged for inverted flight.

The key here is roundness. Making the loop round is very difficult since it requires a continuously changing control input. Typically, loops tend to be flatter on the bottom and wider than they are high as pilots try to keep the bottoms at five (5) feet. A premium should be awarded for roundness when scoring since this is the most difficult aspect of the maneuver. The second thing to watch for is that the three (3) loops are the same size. The natural tendency is for each successive loop to get larger rather than smaller so be ready to spot the growth. The third problem typical to the inside rounds is that they have a tendency to walk to the left or right.

Correct inverted flight is judged when the model makes two (2) smooth, stable laps at normal flight level.

This is dull to watch, but can get interesting for the pilot on a windy day. Expect the plane the climb going into the wind and drop going downwind. As this is a finesse maneuver in wind, be alert to watch for sudden corrections as the plane enters upwind or downwind flight. Other than that, give the devil his due and award a high score if the ship simply motors around at five (5) feet. Rocking of the wings may not be real pleasant to look at, but the emphasis from a scoring standpoint should be on how well altitude is maintained. Score only laps three (3) and four (4) of the minimum six (6) laps allowed.

Correct loops are judged when the model starts from inverted position at normal flight level and makes a series of three (3) smooth, round loops, all in the same place, with the bottoms of the loops at normal flight level and the tops of the loops with the line(s) at 45 degrees elevation. The model then continues for another half loop, recovering at normal flight level.

The comments regarding inside loops apply equally to outside loops. A typical error is for the entry to be lazy from inverted flight resulting in the first loop being egg-shaped to the right. In order for the first loop to be round, the starting input must be quick, yet light, which makes it difficult to execute. Because of the difficulty to correct entry on this maneuver, be ready to catch a mistake at the very beginning.

Consecutive inside square loops are judged correct when the model starts from normal flight level and flies a square course consisting of two (2) loops, each with four (4) inside turns of approximately 4.9 feet radius and straight sized segments with bottom segments at normal flight level and top segments as inverted level flight at 45 degrees elevation. The two (2) bottom corners are equal and so are the two (2) top corners. The maneuver begins and ends with the model in level flight at the point of start of the first turn.

Shape and size is, as in all maneuvers, the main criteria. Almost always, the classic error is long to the right rather than too tall. Most pilots get the first angle correctly, but tend to miss the next two. Descending across the top is the most common mistake, followed by angling out on the vertical leg going down. The bottom right corner tends to be softer than the other three due to the increased airspeed of the plane; so be ready to notice this also. As in the round loops an almost universal tendency is for the second loop to
be larger than the first so be on the alert for this. Squares are particularly hard to fly to the rule book 45 degree, size, so opening these maneuvers is very common. The conscientious judge should be quick to penalize the flier for flying large squares as the maneuver loses most of its difficulty when flown this way.

Consecutive outside square loops are judged correct when the model starts from level flight at 45 degrees elevation and flies a square course (starting with a vertical dive) consisting of two (2) loops, each with four (4) outside turns of approximately 4.9 feet radius and straight equal sized segments with bottom segments inverted at normal flight level and top segments as level flight at 45 degrees elevation. The two (2) bottom corners are equal and so are the two (2) top corners. The maneuver begins and ends with the model in level flight at the point of start of the first turn. The model recovers into normal level flight.

The entry of this maneuver, being a vertical dive at high speed, is somewhat nasty. Frequently, fliers will hedge by entering high or pulling the nose up just before entry. Watch for this and be ready to downgrade here as the entry is the hardest portion of the maneuver. As in the inside squares, there is a tendency for the maneuver to be too wide rather than too high and for the second one to be larger than the first one. Flat bottoms are another area that tends to be weak since the maneuver requires a quick adjustment to inverted flight near the ground.

Correct triangular loops are judged when the model starts from normal level flight and flies a triangular course, starting at the base turn. The three (3) sides of equal length and the three (3) corner angles of equal size. The top corner must be placed at 45 degree elevation. The second triangular loop must be flown in the same flight path as the first one. All corners must be smooth, precise and of approximately 4.9 feet radius.

Problems in shape are very common since it is more difficult to fly a 60 degree angle on demand than a right angle. It is relatively common to see the first angle reasonably close, but the second angle too obtuse, making the third corner too acute. It is particularly hard to keep to the rule book 45 degree size compared to the other maneuvers and the second triangle is usually larger than the first.

Horizontal eights are to be entered and completed at the intersection point of the circles and exit at the same point. The inside loop must be flown first. Correct eights are judged when the model makes two (2) eights, each consisting of two (2) round circles or loops of the same size, tangent to each other, and in a horizontal line. The model must enter the eight from normal flights level and be vertical at the intersection point of tangency of the circles. The eights must be symmetrical. At the top of each circle the model must be at the 45 degrees elevation point; the bottoms of circles must be at normal flight level.

The most common error is overlapping of the intersection, especially on the last outside loop at the end of the maneuver. The result of this is for the maneuver to end up to the right of where it started. The wind tends to make the inside loop move to the left and the outside loop move to the right which accounts for the usual overlapping. The second most common problem is usually a lack of roundness, particularly through the intersection. The transition between insides and outsides must be done very quickly to eliminate flat spots, “X”d, or “S”d intersections. The airplane should momentarily be in a vertical position to prevent the loops from being taller than the width. If a judge is overly concerned with the intersection, it is possible to overlook poor shape. Also, if the loops are round, the intersection will be 
properly placed as a natural consequence. Getting the bottoms at five (5) feet is important, but should definitely be considered secondary to the shape since good shape is difficult on this maneuver.

The eight is to be entered in the direction of the climbing sides of the loops, and after completion of two (2) eights the exit is made in the same direction. The inside loop must be flown first. Correct eights are judged when the model starts a vertical climb and makes a modified inside square loop followed by a modified outside square loop ending with a vertical climb at the same point. The loops are modified so their climbing sides are vertical, and the loops are tangent to each other along these sides, and the turns starting and ending the climbs are 90 degrees. The top sides are slightly shorter than the remaining sides which are of equal length. The maneuver is repeated to form two (2) eights. Tops of loops must be at 45 degrees elevation, bottom of loops must be at normal flight level, and all turns must be smooth, precise, and of approximately 4.9 feet radius.

The intersection tends to be overlapped as in the horizontal round eight, but usually not as much since the square segments provide a better reference for the flier than the round loops. The most frequent shape problem is for the squares to be wider than they are high just as in the inside and outside squares. Once again, too much attention should not be focused on the intersection at the expense of shape. The difficulty in getting the shape correctly should give at least equal importance to shape and placement of the intersection. As in the round eights, good bottoms are important, but secondary to shape and intersection. A common error is not flying the last vertical climb to the 45 degree elevation point at the end of the maneuver.

Vertical eights are to be started at the point of 45 degrees elevation and finished at the same point in inverted flight. The inside loop must be flown first. Correct eights are judged when the model makes two (2) eights, each consisting of two (2) round circles or loops of the same size, tangent to each other, and in a vertical line. The model must be horizontal at the intersection point of tangency of the circles. The eights must be symmetrical, the top of the eights at a point 90 degrees over the flier’s head, and the bottom of the eights at normal flight level.

Far and away the most common problem is flying too big with the maneuver flown behind the flier’s head. Since size is one of the more difficult aspects of this maneuver, exceeding the 45 degree elevation should be downgraded strongly. The next most common error is egg-shaped segments that are wider than they are high. This is caused by not being quick enough during the transitions from insides to outsides. Along with the excess width problem, the plane frequently is not completely horizontal for an instant which going through the transitions. As in the horizontal eights, watch for flat spots, “X”d or “S”d intersections. Once again, the bottom is relatively unimportant compared to the above aspects of the maneuver, i.e., size and shape take precedence over bottoms.

The correct hourglass figure is judged when the model starts from normal flight level and flies an hourglass course starting with an abrupt turn followed by an inverted climb, turns into a wingover path across the circle center for a distance equal to half the total climb, turns into an inverted dive, and recovers at normal flight level. The flight paths of the climb and the dive cross at 45 degrees elevation. The four rounded corners of the figure shall have a radius of approximately 4.9 feet and the flight path forms two (2) equilateral triangles of equal size, turned peak to peak, and one (1) in vertical line above the other.

The m
ost common error is laying the plane too much on its back, i.e., the maneuver is not flown steep enough. When flown properly, the hourglass is over very quickly so there is not much time to catch errors. Like the vertical eight, this maneuver is frequently flown too far in back of the flier, making it much easier to execute. Consequently, the judges should penalize relatively harshly for flying too big. The shape problems are similar to those found in the triangle, i.e., missed angles.

Overhead eights are to be entered and completed at the intersection point of the circles, directly over the flier’s head, and exit from the same point. The inside loop must be flown first. Correct overhead eights are judged when the model makes two (2) eights, each consisting of two (2) round circles of the same size, with the intersection or point of tangency directly over the flier’s head. The model must enter the eights with a vertical climb through the center of the circle, and must always point in this direction at the center of the eights. The eights must be symmetrical and the model at the lowest point of each circle must be at a point of 45 degrees elevation.

No shape can be seen from the judge’s viewpoint. The judgment on the quality of the maneuver must be based solely on angles and the attitude of the plane through the intersection. Look for:

1. Whether or not the lines are perpendicular to the ground at the start of the maneuver.

2. How close the lines are to the 45 degree elevation point as the first inside loop is half completed. The same holds true for the outside loop. Watch for overheads that droop to the left or right, a frequent error on this maneuver. As the ship comes around to the starting point, the first item of importance is whether or not the lines are 90 degrees to the ground. Second, does the plane face exactly away from the judge as it completes the first loop and enters the second (outside) loop. Frequently the pilot “X”s or “S”s the intersection which results in the plane never facing directly away from the judge. Watch for jerky corrections which indicate lack of roundness, even though precise shape cannot be seen.

3. Watch closely that the airplane overlaps the intersection since it is very common for this intersection to be missed.

4. Is the maneuver being flown directly overhead? Frequently the overhead eights are flown in front of the pilot. Since no shape can be seen from the judge’s viewpoint, it is most important to note the attitude of the ship through the intersection. The second eight is a repeat of the first as far as checking for errors is concerned with the exception of the exit. The direction of the exit is another means of checking the accuracy of the shape without actually being able to see from the inside. If the heading is different from that of the entry, then clearly some mistake has been made. The recovery from the exit point to level flight is not scored. As in the wingover, only those judges positioned exactly upwind from the point of entry are in an adequate position to make a good judgment as to the accuracy of this maneuver and for this reason, it would be beneficial for them to bunch up when observing the overhead eights.

The maneuver is entered from level flight at approximately 38 degrees elevation, and consists of one (1) full inside loop, level flight, three-fourths (3/4) of an outside loop, vertical climb, three-fourths (3/4) of an outside loop, level inverted flight, three-fourths (3/4) of an inside loop, and a vertical climb. The right loops are tangent to the left loops along a vertical plane of symmetry through the center of the clover leaf, and the bottom loops are tangent to the top loops. The loops are of equal size and they are connected by horizontal and vertical flight paths. The bottom points of the maneuver shall be at 4.9 feet height, and
the top shall be tangent to the vertical plane through the circle center. When the last loop is performed, the maneuver is made complete by a vertical climb through the center of the four leaf clover.

This maneuver is most often started too high, i.e., closer to 45 degrees instead of 38 degrees as prescribed in the rule book. The next most frequently made mistake is to miss the intersection after the first outside loop. In most cases, the maneuver is flown through the first loop. This is the most critical portion of the maneuver. If this intersection is not correct, there should be a sharp downgrading of the score. This is the essence of the maneuver; any pretense that the maneuver can still be salvaged is nil. The most common error in the horizontal (level and inverted) segment is to climb into the next loop instead of flying straight and level. The same holds true of the vertical climb as a common error is to curve or slant vertical climb to the right or left. Horizontal flight paths and vertical climbs are the only segments of this maneuver that require them to be flown twice, so watch for the second vertical climb to overlap the first. The relative size of the loops is the next most important thing to look for. The most common error is that the loops are not

properly tangential to form a square pattern. The bottoms at five (5) feet, while easily judged, are by far

the easiest part of the maneuver to execute and so do not deserve the attention of the intersection and shape. The maneuver is completed at the 90 degree elevation point on the last vertical climb, so scoring ends there. The recovery to level flight is not scored.

A correct landing is judged when the model descends smoothly to land with no bounce or unusual roughness, and without any part of the model other than the landing gear having touched the ground. Main wheel(s) or three-point landings are permissible. The duration of the flight ends when the model rolls to a stop.

The maneuver is not merely the touchdown, but the entire approach. It is at least equally difficult to make the approach a controlled, constantly descending flight path as it is to make a “no bounce” landing. In other words, judge the approach as well as the touchdown and nothing else.

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