Objective: the student will understand the concepts of attitude flying, how to interpret the glider's attitude using the horizon and visual references, and how to control the glider using the flight controls ### Attitude The attitude of the aircraft simply means the orientation of the aircraft, with respect to the horizon. To control the aircraft, the pilot will continuously monitor and adjust the **pitch** and **bank** attitudes. In order to consistently interpret the aircraft's attitude correctly, the pilot's seated position (both height and forward position) must be set correctly; this can be done with adjustable seats and/or seat cushions. This is specific to the model of aircraft being flown, so ask your flight instructor where your eye level and line of sight should be set when seated in the aircraft. ![[AFH attitude.png]] ### Flight Controls The primary flight controls of the glider are used to control the glider's attitude: - Elevator is used to control motion about the glider's lateral axis, or the pitch, by moving the control stick forward or backward - Ailerons are used to control motion about the glider's longitudinal axis, or roll, by moving the control stick left or right - Rudder is used to control motion about the glider's vertical axis, or yaw, by moving the pedals left or right The control stick should be gripped **very slightly** in the pilot's right hand - any tension or squeezing will inhibit the pilot's sense of how the aircraft is responding or performing, and will greatly accelerate pilot fatigue. The pressure of a few fingertips on the stick should be all that is required to maintain control. ![[GFH axes.png]] Yawing the glider in flight will result in a misalignment of the longitudinal axis with the relative wind; this is known as "sideslip" to aeronautical engineers, or being "uncoordinated" to pilots. There are a few specific circumstances where the pilot may do this intentionally, as in [[Slips to Landing]], but in most cases, the pilot will use the rudder to prevent any undesired yawing, or to remain "coordinated". The pilot can use their bodily sensations ("seat of the pants feeling"), as well as the yaw string to detect yaw. ## Straight Glides ### Purpose When learning straight glides, the student will understand how pitch and bank attitude relate to glider control, how to interpret the pitch and bank attitude using the horizon and visual references, how to use the flight controls to control the glider's attitude, the effects of pitch changes on gliding performance. ### Pitch Attitude The pitch attitude is defined as the angle between the aircraft's longitudinal axis and the horizon. In other words, how far above or below the horizon the aircraft's nose is at any given time. ### Interpreting Pitch Attitude The particular references used are specific to the model of aircraft being flown, but allow the pilot to judge the vertical position of the aircraft's nose with respect to the horizon. In the SGS 2-33, the pilot will assess the vertical position of the horizon on the pitot/static tube mast. In high performance gliders, the pilot will assess the vertical position of the horizon at some distance above the top of the instrument panel, or below the yaw string. At high pitch attitudes, the aircraft's nose may obscure the horizon, so the pilot may need to look off to the left or right side (or use peripheral vision) to accurately interpret the pitch attitude. ![[glider pitch attitude references.jpg]] ### Bank Attitude The bank attitude is defined as the angle between the aircraft's lateral axis and the horizon. In other words, if the aircraft is wings-level, or at some angle to the left or right in relation to the horizon. ### Interpreting Bank Attitude The particular references used are specific to the model of aircraft being flown, but allow the pilot to judge the aircraft's bank with respect to the horizon. When looking straight ahead, the pilot will assess the angle formed between the horizon and fixed references on the aircraft, such as a flat upper surface to the instrument panel, level structural tubing below the canopy, or a projected line through level components in the canopy or instrument panel. Additionally, the pilot should observe the position of the aircraft's wingtips above or below the horizon. ![[glider bank attitude references.jpg]] ### Performing Straight Glides To perform a straight glide, the glider must be flown at a constant pitch attitude, and a wings-level bank attitude. This should result in a constant airspeed and heading. To maintain a constant pitch attitude, the pilot will need to adjust forward or back pressure on the control stick. Pulling the stick back increases the pitch attitude ("raises the nose"), pushing the stick forward decreases the pitch attitude ("lowers the nose"). When the correct pitch attitude has been set, the pilot should use the trim, if available, to **relieve** forward/back control stick pressures, **NOT** to control the glider with the trim. To maintain a wings-level attitude, the pilot may need to adjust left or right pressure on the control stick. Pushing the stick left rolls the aircraft left, pushing the stick right rolls the aircraft right. In a wings-level attitude, the wingtips should be an equal distance above or below the horizon. Additionally, the pilot may need to compensate for any undesired yaw, resulting from turbulence or inadvertently pressing a rudder pedal. Check the yaw string, and adjust rudder pressure to keep it parallel with the longitudinal axis of the glider, or "straight". Pressing the left pedal yaws the glider left, pressing the right pedal yaws the glider right. Apply rudder pressure, or "step on the head" (secured end) of the yaw string to center it. Note the sensations in your body ("seat of the pants feeling") before, during, and after you correct for any yaw. The glider is **controlled** by visually interpreting the attitude. 90% of the pilot's time should be spent looking outside, interpreting the aircraft's attitude, and scanning for other traffic in the air. 10% of the time may be spent checking on the glider's **performance** by scanning the appropriate flight instruments. In practice, this means that the pilot will **briefly** shift the eyes inside to scan the flight instrument once or twice every 10 seconds. ### Glider Performance During Straight Glides Raising the pitch of the glider always has the effect of decreasing the airspeed; lowering the pitch always increases airspeed. The pilot should note the specific pitch attitudes corresponding to certain speeds. As this becomes more comfortable, additional configurations (spoilers, flaps, etc) may be introduced; note how the correct pitch attitude changes to achieve the desired performance when configuration is changed. The pilot will use multiple cues to achieve the desired aircraft performance during straight glides. The pilot will monitor and **control** the glider's pitch attitude using the horizon and visual references, but will also note changes in the indicated airspeed, the sound of the air rushing over the canopy, and the feel of the flight controls. As airspeed increases, more airflow passes over the flight control surfaces; the flight controls become more effective, and the stick feels more firm in the pilot's hand. When the glider is flown in a wings-level bank attitude, the heading should remain constant. In conditions of zero wind, or a direct headwind or tailwind, the glider will fly towards whatever visual landmark exists straight ahead. If there is any component of a crosswind to the glider's flight path, the glider may appear to fly slightly "sideways" - in reality, the glider is still flying straight through the air, but the air mass itself is drifting with respect to the ground below. This is perfectly normal, and pilots establish a **wind correction angle**, or "crab" to compensate for the effects of wind drift. ### Common Errors - Rough or erratic control applications - Gripping the stick too tightly - Attempting to control the aircraft by reference to the flight instruments, rather than the horizon and visual references - Improper use of trim; failing to use trim, or attempting to control the aircraft with the trim - Failure to recognize and correct for uncoordinated flight ### Completion Standards - For initial attempts: understands the concepts of attitude flying, how to interpret the glider's attitude using the horizon and visual references, and how to control the glider using the flight controls. Establishes and maintains the correct attitude for the desired performance with instructor assistance. - For solo, sport, and private pilots: maintains specified airspeed ±10kts, specified heading ±10° - For commercial pilots: maintains specified airspeed ±5kts, specified heading ±10° ## Turns ### Purpose When learning turns, the student will further understand how pitch and bank attitude relate to glider control, how to interpret the pitch and bank attitude using the horizon and visual references, how to use the flight controls to control the glider's attitude, the factors affecting the glider's turning performance. ### Attitude The pitch and bank attitude of the glider are interpreted and controlled in exactly the same way as during straight glides. The pilot should maintain the same relaxed, neutral posture during turns and "ride the turn with the glider"; attempting to lean in response to a turn will inhibit proper attitude interpretation and aircraft control. ### Performing Turns To perform a turn, the glider should be flown at a constant pitch and bank attitude. As in straight glides, the pitch attitude will control the glider's speed during turns. Establishing a bank results in the generation of a horizontal component of lift - this horizontal component of lift is what causes the glider to turn. Before beginning a turn, the pilot must visually clear the area in the direction of the turn; then, look straight ahead to establish the correct pitch and bank attitude. To roll in to the turn, the pilot will apply pressure on the control stick in the direction of the desired roll. At the same time, the glider will experience [[Adverse Yaw]], and have a tendency to yaw opposite to the direction it is rolling; the pilot will also need to apply rudder pressure in the same direction as the roll to eliminate this tendency. As bank angle is increased, the vertical component of lift will decrease, and the glider will have a tendency to reduce the pitch attitude; the pilot must compensate for this by increasing back pressure on the stick to maintain the desired pitch attitude. In a medium banked turn (approximately 20-30°), the glider will remain in the desired bank attitude without the need for left or right stick pressure. In shallower turns, the natural stability of the glider's design will cause a tendency to roll bank to a wings-level attitude, so some stick pressure in the direction of the turn will be required. In [[Steep Turns]], the glider will experience an [[Overbanking Tendency]], and tend to roll into a progressively steeper bank attitude unless opposite stick pressure is applied. To roll out of the turn and return to a straight glide, the pilot will apply pressure to the control stick opposite to the direction of the turn, and again use rudder in the same direction as the roll to eliminate adverse yaw. Likewise, any additional back pressure on the stick will be neutralized as lift returns to a completely vertical force vector. The pilot will need to initiate the roll-out prior to reaching the desired heading. The rule-of-thumb for this is to lead the desired heading by half of the bank angle. For example, during a 30° banked turn, begin the roll-out approximately 15° before the desired heading. This should be accomplished by selecting a visual heading reference that corresponds to the desired completion heading. The pilot should be alert to any tendency to [[Slip]] or [[Skid]] during turns. Like in straight glides, check the yaw string, and "step on the head" (secured end) to keep it parallel with the longitudinal axis of the glider. Note the sensations in your body ("seat of the pants feeling") before, during, and after you correct for any yaw. ![[GFH slip skid.png]] ### Glider Performance During Turns Turning performance is defined in terms of [[Radius of Turn]] and [[Rate of Turn]]. Increasing the bank angle decreases radius of turn and increases rate of turn. The glider's airspeed will also affect turning performance: at a given angle of bank, a higher airspeed will increase radius of turn and decrease rate of turn. In other words, higher bank angles and slower speeds will improve turning performance. The glider must generate more total lift during a turn, and will experience an increase in [[Load Factor]] as a result. [[Load Factor and Stall Speed]] are related; increasing load factor will increase the glider's stall speed. In fact, all performance speeds (stall, minimum sink, best glide, etc) are affected by load factor and bank angle, so [[Correcting Performance Speeds]] are necessary when performing turns. ### Common Errors - Failure to visually clear before turning - Under- or overcompensating for adverse yaw - Failure to compensate for decreased vertical component of lift - Rough or erratic control applications - Gripping the stick too tightly - Failure to maintain the desired angle of bank - Under- or overshooting the desired completion heading ### Completion Standards - For initial attempts: understands the concepts of attitude flying, how to interpret the glider's attitude using the horizon and visual references, and how to control the glider using the flight controls. Establishes and maintains the correct attitude for the desired bank angle and rolls out on the selected heading with instructor assistance. - For solo, sport, and private pilots: maintains specified airspeed ±10kts, rolls out on specified heading ±10° - For commercial pilots: maintains specified airspeed ±5kts, rolls out on specified heading ±10° ### Additional Resources [<iframe width="560" height="315" src="https://www.youtube.com/embed/xhoOwKM7pOA?si=bCGXKPzj1sv5F5Lh" title="YouTube video player" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share" referrerpolicy="strict-origin-when-cross-origin" allowfullscreen></iframe>] ## References - FAA, *Glider Flying Handbook* - FAA, *Airplane Flying Handbook* - FAA, *Practical Test Standards for Glider Category*