If you have been an avid reader of my columns, you are aware that I like to explore subjects that pertain to both expert and beginner pilots. After all, guidance is needed when you are first starting out in the competition scene, and experience pays off! I want to spend some time going over a topic that I have not yet covered in its entirety, and that is the cross-box elements that are commonly found in the more advanced International Miniature Aerobatic Club (IMAC) schedules. Traditionally, maneuvers are flown on the X and Y (horizontal and vertical) axes. However, a cross-box maneuver is one that is flown on the Z-axis, which is either going away from, or coming toward, the pilot. After reviewing the first three IMAC classes, I found maneuvers five, six, and 10 of the 2013 Intermediate schedule interesting, because they would tie perfectly into my discussion about cross-box maneuvers, especially since two of these maneuvers are flown back-to-back. Careful planning is needed so the figures will be flown to the best of the pilot’s ability for the clearest possible presentation. Over the course of this column, I will discuss some flight techniques that will assist you in these maneuvers and examine some judging criteria that pertain to these figures. Without further delay, let’s begin! A Perfect Cross-Box Combo Although three cross-box maneuvers exist in the 2013 Intermediate program, the first two (the fifth and sixth maneuvers) are the most challenging, because one exits cross-box and the other begins immediately after. I will break these two maneuvers down and describe each one. Then, I will cover a few flight tips to decrease your workload. The fifth maneuver from the 2013 Intermediate program is a 11/4 positive spin Flying cross-box maneuversby John [email protected] 50cc Yak 55M from Goldwing RC is a great performer and is perfect for the entry-level classes found in IMAC competition. followed by a half roll in the same direction as the spin. This maneuver starts parallel to the runway. After the airplane stalls and the direction of the rotation is chosen by a wingtip dropping during the stall, the pilot must perform 11/4 positive spin rotations. After the rotation is complete, a brief line segment should be shown and then the pilot immediately executes a half roll. Then another line segment, longer than the one performed earlier, is performed before pushing to an inverted cross-box exit. It is important to be precise in the spin rotation and the half roll so that when pushing to exit the maneuver, the aircraft is perpendicular to the runway and traveling either away or toward the pilot. Per the rule book, the end of a figure is shown when horizontal flight that is equivalent to one fuselage airplane length is completed. After this point, the next figure will commence. If a line segment is not shown to differentiate between one maneuver and the next, one-point-per-figure deduction must be applied by all judges. If you are using dual and/or triple rates, you will likely need to switch rates between the spin and the Humpty Bumps. It is important to have enough control surface deflection to spin and snap the aircraft on one rate, and have the aircraft be extremely precise on another for maneuvers such as the Humpty Bump. Next the pilot must execute two variations of the popular Humpty Bump. Begin by pushing to a vertical up-line and performing a full roll. Then push a half outside loop and perform three 125Model Aviation February 2013www.ModelAviation.comRC SCALE AEROBATICS125
The diagonal line between the completion of maneuver five and the start of maneuver six indicates a cross-box exit and entry flown along the Z-axis. A solid circle indicates the start of a maneuver and a solid black line marks its completion.points of a four-point roll down. Pull half of an inside loop to a vertical up-line and perform two points of a four-point roll, which must be flown at a constant roll rate, with the roll centered on the vertical up-line. Finally, push to an upright exit so that the airplane is again flying parallel to the runway. The key to this maneuver is planning ahead and anticipating its spin rotation so that the Humpty Bumps will not appear “rushed.” In the event that a strong crosswind exists, the pilot must quickly react. Suppose that there is a strong crosswind blowing in. If the pilot exits the spin coming toward him or herself, he or she must almost immediately go into the next maneuver. Wind correcting is a must so the airplane will not drift, and the radii of the loops must be well planned so the airplane will exit the maneuver at the proper distance from the pilot. For all of these figures, the radii of 126Model Aviation February 2013www.ModelAviation.comRC SCALE AEROBATICS125
This depicts a 90° rolling circle with a roll to the inside. Note the cross-box exit, which is indicated by a diagonal line since this maneuver is only flown on the X and Z axes.the first and last partial loop must also be equal; however, the half loop in the middle of the figure can be of a different radius. It is important to note that size is important. Despite the fact that a pilot can perform a small radius to the vertical portion of the Humpty Bump, if a judge feels that the radius is too sharp, a downgrade may ensue. Remember that the radius after the half outside loop must match, but in this case, you will need to immediately continue that radius into another Humpty Bump variation. The Roller Maneuver 10 is a 90° rolling turn with one roll to the inside. Although it starts in a manner that is parallel to the runway, the airplane will exit cross-box. The roll is integrated, which means that a constant roll rate exists throughout the turn. A judge will look at the entry and exit altitude as well as the cardinal points. In this case, the airplane must start the maneuver upright along the X-axis, and exit upright along the Z-axis. Points will be taken off with roll-rate variation, a rate change in the turn, or similar variances. I recommend that this maneuver always be flown so that it is completed while traveling away from the pilot. This is beneficial so the pilot will have time to complete the maneuver, show that the airplane has traveled one full fuselage length to mark the end of the maneuver, and turn away and prepare for landing. Depending on the direction that the sequence is flown, the pilot will need to be proficient rolling to both the left and right. Pilots naturally tend to prefer to roll to one direction. Although this is acceptable for the average pilot, it isn’t for the competition pilot. Final Thoughts To the aerobatic newcomer, cross-box figures may be challenging at first. The perspective of the aircraft may be rather strange compared to traditional X- and Y-axis flight. Additionally, these maneuvers can become difficult to fly depending on the severity of the wind during the flight. As discussed, some maneuvers are flown back-to-back while being flown cross-box. Careful, strategic planning results in the highest mark. For these reasons, it is extremely important to practice in all weather conditions. After all, you don’t know what will happen on the competition day! Until next time, fly hard! SOURCES: Goldwing [email protected] IMACwww.mini-iac.com127Model Aviation February 2013www.ModelAviation.com125
Edition: Model Aviation - 2013/02
Page Numbers: 125,126,127
Edition: Model Aviation - 2013/02
Page Numbers: 125,126,127
If you have been an avid reader of my columns, you are aware that I like to explore subjects that pertain to both expert and beginner pilots. After all, guidance is needed when you are first starting out in the competition scene, and experience pays off! I want to spend some time going over a topic that I have not yet covered in its entirety, and that is the cross-box elements that are commonly found in the more advanced International Miniature Aerobatic Club (IMAC) schedules. Traditionally, maneuvers are flown on the X and Y (horizontal and vertical) axes. However, a cross-box maneuver is one that is flown on the Z-axis, which is either going away from, or coming toward, the pilot. After reviewing the first three IMAC classes, I found maneuvers five, six, and 10 of the 2013 Intermediate schedule interesting, because they would tie perfectly into my discussion about cross-box maneuvers, especially since two of these maneuvers are flown back-to-back. Careful planning is needed so the figures will be flown to the best of the pilot’s ability for the clearest possible presentation. Over the course of this column, I will discuss some flight techniques that will assist you in these maneuvers and examine some judging criteria that pertain to these figures. Without further delay, let’s begin! A Perfect Cross-Box Combo Although three cross-box maneuvers exist in the 2013 Intermediate program, the first two (the fifth and sixth maneuvers) are the most challenging, because one exits cross-box and the other begins immediately after. I will break these two maneuvers down and describe each one. Then, I will cover a few flight tips to decrease your workload. The fifth maneuver from the 2013 Intermediate program is a 11/4 positive spin Flying cross-box maneuversby John [email protected] 50cc Yak 55M from Goldwing RC is a great performer and is perfect for the entry-level classes found in IMAC competition. followed by a half roll in the same direction as the spin. This maneuver starts parallel to the runway. After the airplane stalls and the direction of the rotation is chosen by a wingtip dropping during the stall, the pilot must perform 11/4 positive spin rotations. After the rotation is complete, a brief line segment should be shown and then the pilot immediately executes a half roll. Then another line segment, longer than the one performed earlier, is performed before pushing to an inverted cross-box exit. It is important to be precise in the spin rotation and the half roll so that when pushing to exit the maneuver, the aircraft is perpendicular to the runway and traveling either away or toward the pilot. Per the rule book, the end of a figure is shown when horizontal flight that is equivalent to one fuselage airplane length is completed. After this point, the next figure will commence. If a line segment is not shown to differentiate between one maneuver and the next, one-point-per-figure deduction must be applied by all judges. If you are using dual and/or triple rates, you will likely need to switch rates between the spin and the Humpty Bumps. It is important to have enough control surface deflection to spin and snap the aircraft on one rate, and have the aircraft be extremely precise on another for maneuvers such as the Humpty Bump. Next the pilot must execute two variations of the popular Humpty Bump. Begin by pushing to a vertical up-line and performing a full roll. Then push a half outside loop and perform three 125Model Aviation February 2013www.ModelAviation.comRC SCALE AEROBATICS125
The diagonal line between the completion of maneuver five and the start of maneuver six indicates a cross-box exit and entry flown along the Z-axis. A solid circle indicates the start of a maneuver and a solid black line marks its completion.points of a four-point roll down. Pull half of an inside loop to a vertical up-line and perform two points of a four-point roll, which must be flown at a constant roll rate, with the roll centered on the vertical up-line. Finally, push to an upright exit so that the airplane is again flying parallel to the runway. The key to this maneuver is planning ahead and anticipating its spin rotation so that the Humpty Bumps will not appear “rushed.” In the event that a strong crosswind exists, the pilot must quickly react. Suppose that there is a strong crosswind blowing in. If the pilot exits the spin coming toward him or herself, he or she must almost immediately go into the next maneuver. Wind correcting is a must so the airplane will not drift, and the radii of the loops must be well planned so the airplane will exit the maneuver at the proper distance from the pilot. For all of these figures, the radii of 126Model Aviation February 2013www.ModelAviation.comRC SCALE AEROBATICS125
This depicts a 90° rolling circle with a roll to the inside. Note the cross-box exit, which is indicated by a diagonal line since this maneuver is only flown on the X and Z axes.the first and last partial loop must also be equal; however, the half loop in the middle of the figure can be of a different radius. It is important to note that size is important. Despite the fact that a pilot can perform a small radius to the vertical portion of the Humpty Bump, if a judge feels that the radius is too sharp, a downgrade may ensue. Remember that the radius after the half outside loop must match, but in this case, you will need to immediately continue that radius into another Humpty Bump variation. The Roller Maneuver 10 is a 90° rolling turn with one roll to the inside. Although it starts in a manner that is parallel to the runway, the airplane will exit cross-box. The roll is integrated, which means that a constant roll rate exists throughout the turn. A judge will look at the entry and exit altitude as well as the cardinal points. In this case, the airplane must start the maneuver upright along the X-axis, and exit upright along the Z-axis. Points will be taken off with roll-rate variation, a rate change in the turn, or similar variances. I recommend that this maneuver always be flown so that it is completed while traveling away from the pilot. This is beneficial so the pilot will have time to complete the maneuver, show that the airplane has traveled one full fuselage length to mark the end of the maneuver, and turn away and prepare for landing. Depending on the direction that the sequence is flown, the pilot will need to be proficient rolling to both the left and right. Pilots naturally tend to prefer to roll to one direction. Although this is acceptable for the average pilot, it isn’t for the competition pilot. Final Thoughts To the aerobatic newcomer, cross-box figures may be challenging at first. The perspective of the aircraft may be rather strange compared to traditional X- and Y-axis flight. Additionally, these maneuvers can become difficult to fly depending on the severity of the wind during the flight. As discussed, some maneuvers are flown back-to-back while being flown cross-box. Careful, strategic planning results in the highest mark. For these reasons, it is extremely important to practice in all weather conditions. After all, you don’t know what will happen on the competition day! Until next time, fly hard! SOURCES: Goldwing [email protected] IMACwww.mini-iac.com127Model Aviation February 2013www.ModelAviation.com125
Edition: Model Aviation - 2013/02
Page Numbers: 125,126,127
If you have been an avid reader of my columns, you are aware that I like to explore subjects that pertain to both expert and beginner pilots. After all, guidance is needed when you are first starting out in the competition scene, and experience pays off! I want to spend some time going over a topic that I have not yet covered in its entirety, and that is the cross-box elements that are commonly found in the more advanced International Miniature Aerobatic Club (IMAC) schedules. Traditionally, maneuvers are flown on the X and Y (horizontal and vertical) axes. However, a cross-box maneuver is one that is flown on the Z-axis, which is either going away from, or coming toward, the pilot. After reviewing the first three IMAC classes, I found maneuvers five, six, and 10 of the 2013 Intermediate schedule interesting, because they would tie perfectly into my discussion about cross-box maneuvers, especially since two of these maneuvers are flown back-to-back. Careful planning is needed so the figures will be flown to the best of the pilot’s ability for the clearest possible presentation. Over the course of this column, I will discuss some flight techniques that will assist you in these maneuvers and examine some judging criteria that pertain to these figures. Without further delay, let’s begin! A Perfect Cross-Box Combo Although three cross-box maneuvers exist in the 2013 Intermediate program, the first two (the fifth and sixth maneuvers) are the most challenging, because one exits cross-box and the other begins immediately after. I will break these two maneuvers down and describe each one. Then, I will cover a few flight tips to decrease your workload. The fifth maneuver from the 2013 Intermediate program is a 11/4 positive spin Flying cross-box maneuversby John [email protected] 50cc Yak 55M from Goldwing RC is a great performer and is perfect for the entry-level classes found in IMAC competition. followed by a half roll in the same direction as the spin. This maneuver starts parallel to the runway. After the airplane stalls and the direction of the rotation is chosen by a wingtip dropping during the stall, the pilot must perform 11/4 positive spin rotations. After the rotation is complete, a brief line segment should be shown and then the pilot immediately executes a half roll. Then another line segment, longer than the one performed earlier, is performed before pushing to an inverted cross-box exit. It is important to be precise in the spin rotation and the half roll so that when pushing to exit the maneuver, the aircraft is perpendicular to the runway and traveling either away or toward the pilot. Per the rule book, the end of a figure is shown when horizontal flight that is equivalent to one fuselage airplane length is completed. After this point, the next figure will commence. If a line segment is not shown to differentiate between one maneuver and the next, one-point-per-figure deduction must be applied by all judges. If you are using dual and/or triple rates, you will likely need to switch rates between the spin and the Humpty Bumps. It is important to have enough control surface deflection to spin and snap the aircraft on one rate, and have the aircraft be extremely precise on another for maneuvers such as the Humpty Bump. Next the pilot must execute two variations of the popular Humpty Bump. Begin by pushing to a vertical up-line and performing a full roll. Then push a half outside loop and perform three 125Model Aviation February 2013www.ModelAviation.comRC SCALE AEROBATICS125
The diagonal line between the completion of maneuver five and the start of maneuver six indicates a cross-box exit and entry flown along the Z-axis. A solid circle indicates the start of a maneuver and a solid black line marks its completion.points of a four-point roll down. Pull half of an inside loop to a vertical up-line and perform two points of a four-point roll, which must be flown at a constant roll rate, with the roll centered on the vertical up-line. Finally, push to an upright exit so that the airplane is again flying parallel to the runway. The key to this maneuver is planning ahead and anticipating its spin rotation so that the Humpty Bumps will not appear “rushed.” In the event that a strong crosswind exists, the pilot must quickly react. Suppose that there is a strong crosswind blowing in. If the pilot exits the spin coming toward him or herself, he or she must almost immediately go into the next maneuver. Wind correcting is a must so the airplane will not drift, and the radii of the loops must be well planned so the airplane will exit the maneuver at the proper distance from the pilot. For all of these figures, the radii of 126Model Aviation February 2013www.ModelAviation.comRC SCALE AEROBATICS125
This depicts a 90° rolling circle with a roll to the inside. Note the cross-box exit, which is indicated by a diagonal line since this maneuver is only flown on the X and Z axes.the first and last partial loop must also be equal; however, the half loop in the middle of the figure can be of a different radius. It is important to note that size is important. Despite the fact that a pilot can perform a small radius to the vertical portion of the Humpty Bump, if a judge feels that the radius is too sharp, a downgrade may ensue. Remember that the radius after the half outside loop must match, but in this case, you will need to immediately continue that radius into another Humpty Bump variation. The Roller Maneuver 10 is a 90° rolling turn with one roll to the inside. Although it starts in a manner that is parallel to the runway, the airplane will exit cross-box. The roll is integrated, which means that a constant roll rate exists throughout the turn. A judge will look at the entry and exit altitude as well as the cardinal points. In this case, the airplane must start the maneuver upright along the X-axis, and exit upright along the Z-axis. Points will be taken off with roll-rate variation, a rate change in the turn, or similar variances. I recommend that this maneuver always be flown so that it is completed while traveling away from the pilot. This is beneficial so the pilot will have time to complete the maneuver, show that the airplane has traveled one full fuselage length to mark the end of the maneuver, and turn away and prepare for landing. Depending on the direction that the sequence is flown, the pilot will need to be proficient rolling to both the left and right. Pilots naturally tend to prefer to roll to one direction. Although this is acceptable for the average pilot, it isn’t for the competition pilot. Final Thoughts To the aerobatic newcomer, cross-box figures may be challenging at first. The perspective of the aircraft may be rather strange compared to traditional X- and Y-axis flight. Additionally, these maneuvers can become difficult to fly depending on the severity of the wind during the flight. As discussed, some maneuvers are flown back-to-back while being flown cross-box. Careful, strategic planning results in the highest mark. For these reasons, it is extremely important to practice in all weather conditions. After all, you don’t know what will happen on the competition day! Until next time, fly hard! SOURCES: Goldwing [email protected] IMACwww.mini-iac.com127Model Aviation February 2013www.ModelAviation.com125
