GB/T 47588-2026Flight test requirements for manned airships (English PDF)

5.1 Takeoff performance

5.1.1 Test Conditions The experimental conditions are as follows:

a) Weight and center of gravity are as follows: 1) Maximum net weight and front center of gravity; 2) Maximum net weight and rear center of gravity.

b) Power status is as follows: 1) Full engine takeoff power; 2) Single-engine shutdown takeoff power (for multi-engine airships).

c) The thrust vector angle is as follows: 1) At a given location (for vertical takeoff); 2) At the takeoff design values (for runway takeoff).

d) The wind speed and direction are stable, and the equipment is equipped to measure the ground wind speed and direction. The takeoff wind speed meets the takeoff restrictions of the model.

5.1.2 Test Methods

5.1.2.1 Vertical Takeoff The vertical takeoff method is as follows:

a) Take off into the wind, determine the takeoff power; the thrust vector angle is generally greater than 60°. After the field height reaches 15m, adjust the thrust vector angle appropriately and transition to... steady climb;

b) Each state point shall be tested no less than twice.

5.1.2.2 Takeoff The takeoff method is as follows:

a) Take off into the wind and determine takeoff power;

b) During acceleration, maintain a stable pitch and yaw angle as much as possible. After accelerating to takeoff speed, pull up the stick to lift off. After takeoff, do not exceed the required pitch angle. After exceeding the limit value, the field height reaches 15m and then transitions to steady-state climbing.

c) Each state point shall be tested no less than twice.

5.1.3 Data Recording and Processing

5.1.3.1 Recorded parameters include. indicated airspeed, pressure altitude, atmospheric static temperature, surface wind speed and direction, yaw angle, engine speed, thrust vector angle, etc. Navigation horizontal speed, navigation vertical speed, navigation position, navigation altitude.

5.1.3.2 By recording parameters, plot curves of horizontal displacement, height, and velocity as a function of time to determine the acceleration start time, the time of liftoff, and the time of return. At a height of 15m, the following results are given.

a) Vertical Takeoff. Provide the takeoff time and distance from ground level to 15m altitude, and the vertical takeoff distance at the moment of takeoff to 15m altitude. linear velocity;

b) Takeoff with a runway. Provide the takeoff runway distance and time from the start of acceleration to the airship's departure from the area. Takeoff distance and takeoff time within the 15m high zone. For multiple tests at the same state point, the arithmetic mean is taken; if necessary, the takeoff performance results can be converted to standard atmospheric conditions. Results at different heights.

5.2 Climbing performance

5.2.1 Test Conditions The experimental conditions are as follows:

a) Weight, center of gravity. maximum net weight, front center of gravity.

b) Power status is as follows: 1) All payments are made on demand; 2) Single-launch stop as needed (for multi-launch airships).

c) Thrust vector angle. Design value for normal climb.

d) The wind speed and direction in the air are stable, with no obvious turbulence; the wind speed in the air meets the operating restrictions of the model.

5.2.2 Test Methods

5.2.2.1 Normal Climb Rate The normal climb rate test method is as follows:

a) Within the preset test altitude range, using preset power states (2 to 3, including full-power continuous state) and climb angle. (2 to 3) Perform a stable ascent;

b) Maintain constant power and climb angle during this period. Once airspeed and rate of climb stabilize, continue this for at least 5 seconds, recording the climb rate and climb angle. rate of lift and elevator deflection;

c) Each state point shall be tested no less than twice.

5.2.2.2 Continuous Maximum Rate of Ascent The method for testing the continuous maximum rate of ascent is as follows:

a) Continuous maximum climb rate test method. Set the power to at least 70% of maximum continuous power for level flight. After the airspeed stabilizes, pull back on the stick to climb. Slowly increase the elevator deflection to increase the climb rate (power can be further increased as needed);

b) When the power, elevator, or pitch angle reaches its maximum limit and the airbag pressure differential remains stable within the normal range, or when the power, elevator, or... When the elevation angle has not reached the maximum limit but the airbag pressure differential has reached the upper limit of the normal range and can remain stable, record the rate of climb at this time. Maximum continuous climb rate;

c) The continuous maximum rate of ascent is tested more than 3 times within the selected altitude range.

5.2.3 Data Recording and Processing

5.2.3.1 Recorded parameters include. barometric altitude, indicated airspeed, vertical speed, atmospheric static temperature, pitch angle, navigation horizontal speed, and navigation vertical speed. Altitude, navigation altitude, engine speed, control surface deflection angle, airbag pressure difference, and auxiliary airbag pressure difference.

5.2.3.2 Plot curves of indicated airspeed, pitch angle, rate of climb, and airbag pressure differential as a function of time. Select data from the stable climb phase for analysis. The stable climb rate and continuous maximum climb rate of the airship at different state points are calculated. For multiple normal climb rate results at the same state point, the arithmetic operation is performed. Average value; for continuous maximum climb rate, the relatively conservative (smaller) result from multiple valid results should be taken.

5.3 Level Flight Performance

5.3.1 Test Conditions The experimental conditions are as follows:

a) Weight and center of gravity are as follows: 1) Normal net weight, normal center of gravity; 2) Maximum net weight and forward center of gravity (only for minimum level flight speed test).

b) Power status. Full power generation on demand.

c) Thrust vector angle. cruise design value.

d) The wind speed and direction in the air are stable, with no obvious turbulence; the wind speed in the air meets the operating restrictions of the model.

5.3.2 Test Methods

5.3.2.1 Basic performance in level flight The basic performance test methods for level flight are as follows:

a) Select several altitude points (including the design cruise altitude) to conduct level flight performance tests, and control the rudder at each altitude with a preset power setting. To ensure the airship flies straight, maintain altitude and heading during level flight, while simultaneously observing changes in indicated airspeed and engine speed. Due to the varying power configurations and sizes of different airships, their acceleration and deceleration performance differs significantly. The level flight trim point requires consideration of airspeed and dynamic range. Data should be read only after the force and speed have stabilized, and level flight trim tests should be performed at least twice at each state point.

b) When the power state is at full engine maximum continuous power during level flight, the steady airspeed at this time is the maximum level flight speed at the corresponding altitude;

c) When the airship is flying at maximum net weight and forward center of gravity, gradually reduce the throttle from a moderate level flight speed while simultaneously maneuvering the control surfaces to maintain the original altitude. The indicated airspeed when altitude becomes unmaintainable is the minimum level flight speed at maximum net weight.

5.3.2.2 Level Flight Acceleration and Deceleration Performance The test method for acceleration and deceleration performance during level flight is as follows:

a) Set the indicated airspeed for the start and end points of the acceleration process as needed, level off at the given altitude to the indicated airspeed at the start point, and operate normally. The gate opens to its maximum speed, and the airship gradually accelerates until it reaches the indicated airspeed at the finish line, after which the acceleration ends.

b) Set the indicated airspeed at the start and end of the deceleration process as needed. At the given altitude, trim to the indicated airspeed at the start and reduce fuel normally. The accelerator is moved to a low throttle position, and the airship gradually decelerates until the indicated airspeed at the finish line ends.

c) Acceleration/deceleration tests at each altitude shall be conducted no less than twice, and the entire process shall be combined with control surface manipulation to keep the airship flying in a straight line at an altitude.

5.3.2.3 Steady-state rotation performance The test method for steady-state rotation performance is as follows:

a) Trial flight at a given altitude (1-2) and indicated airspeed (2-3), with power remaining constant, selecting 2-3 [airspeeds/airspeeds]. Maintaining rudder deflection (from 1/3 full to full) allows the airship to enter a stable hover at a constant altitude (this can be coordinated with elevator adjustments). (to maintain height)

b) After the circling airspeed and yaw rate stabilize, continue circling at a yaw angle of not less than 540° and then terminate the operation;

c) Each state point shall be tested no less than twice.

5.3.3 Data Recording and Processing

5.3.3.1 Recorded parameters include. barometric altitude, indicated airspeed, vertical speed, navigation horizontal speed, navigation altitude, navigation position, and throttle position. Engine speed, elevator deflection, rudder deflection, pitch angle, yaw angle, and track deflection.

5.3.3.2 Experimental data processing includes the following.

a) Provide the indicated airspeed (including maximum level flight speed) for level flight trim at different altitudes and power settings for the airship;

b) Give the minimum indicated airspeed for level flight of the airship at maximum net weight and forward center of gravity;

c) For level flight acceleration and deceleration tests. plot the changes in indicated airspeed, engine speed, and throttle position over time during the airship's acceleration and deceleration processes. The curves provide acceleration time, acceleration distance, deceleration time, and deceleration distance within the set speed range.

d) For steady-state hovering tests. plot the hovering plane trajectory at different altitudes, speeds, and rudder deflections in different directions, and provide the results for different... The stable turning radius and stable yaw rate at the state point (the influence of wind makes the turning trajectory generally a centroidal translation with the wind direction) The ellipse can be shaped like a parallel line, and the short radius of the 540° yaw ellipse trajectory can be used as the steady-state turning radius.

5.4 Sliding performance

5.4.1 Test Conditions The experimental conditions are as follows:

a) Weight, center of gravity. maximum net weight, rear center of gravity.

b) Power status is as follows: 1) All payments are made on demand; 2) Single-launch stop as needed (for multi-launch airships).

c) Thrust vector angle. Design value for normal glide.

d) The wind speed and direction in the air are stable, with no obvious turbulence; the wind speed in the air meets the operating restrictions of the model.

5.4.2 Test Methods

5.4.2.1 Normal Decline Rate The normal decline rate test method is as follows:

a) Normal descent rate test method. Within a preset test altitude range, at a preset power state (2 to 3, including full-power maximum continuous operation)... (Continued state) and glide angle (2-3) for stable glide;

b) Maintain the power state and descent angle unchanged during this period. After the airspeed and descent rate stabilize, continue for more than 5 seconds and record the descent speed and descent rate. Descent rate and elevator deflection angle;

c) Each state point shall be tested no less than twice.

5.4.2.2 Maximum rate of continuous decline The method for testing the continuous maximum rate of decline is as follows:

a) Set the power to at least 50% of maximum continuous power for level flight;

b) After the airspeed stabilizes, push the stick down and slowly increase the elevator deflection to increase the descent rate (power can be further increased as needed);

c) When the power, elevator, or pitch angle reaches its maximum limit and the airbag pressure differential remains stable within the normal range, or when the power, elevator, or pitch angle reaches its maximum limit... If the depression angle does not reach the maximum limit but the airbag pressure differential has reached the lower limit of the normal range and can remain stable, record the descent rate at this time. As the maximum continuous rate of decline;

d) The maximum rate of descent is tested more than 3 times within the selected height range.

5.4.2.3 Dive-and-Pull-Up Performance The test method for dive-pull performance is as follows:

a) Select several combinations of dive angles and airspeeds as test points;

b) Level flight within the preset altitude range according to the given power settings;

c) Gradually push the stick to bring the airship into a dive at a given angle. Once the speed reaches the set value, pull the stick to recover from the dive (after recovering from the dive). (Without changing the power settings), it climbs back to the original height to prepare for the next test point;

d) Each state point shall be tested no less than twice.

6.1 Longitudinal Maneuvering

6.1.1 Test Conditions The experimental conditions are as follows:

a) Weight and center of gravity are as follows: 1) Normal net weight and front center of gravity; 2) Normal net weight and rear center of gravity.

b) Power status. Full power generation on demand.

c) Thrust vector angle. cruise design value.

d) The wind speed and direction in the air are stable, with no obvious turbulence.

6.1.2 Test Methods The longitudinal manipulation test method is as follows:

a) At a given altitude, perform level flight trim by selecting 2 to 3 airspeeds from 50% to 100% of the maximum level flight speed; pull... By manipulating the elevator upwards with the stick, the airship's pitch angle gradually increases to 30°. Then, push the stick downwards to recover and return to level flight. If the maximum pitch angle is less than... The 30° angle is based on the actual maximum achievable elevation angle.

b) At a given altitude, perform level flight trim by selecting 2 to 3 speeds from 50% to 100% of the maximum level flight speed; push... If the elevator is deflected downwards using the stick, the airship's nose-down angle gradually increases to -30°. Pulling back on the stick to tilt the airship back up and restore level flight will cause it to tilt further. If the maximum nose-down angle is less than... -30° is based on the actual maximum achievable angle of depression.

c) The operating speed of the lever or push lever can be fast or slow, and multiple tests can be conducted as needed to observe the pitch response characteristics of the airship at various state points. The longitudinal manipulation test shall be conducted no less than twice.

6.1.3 Data Recording and Processing

6.1.3.1 Recorded parameters include. barometric altitude, indicated airspeed, vertical speed, static temperature, pitch angle, longitudinal overload, normal overload, and power steering. Speed, control surface deflection angle, control stick force (if necessary).

6.1.3.2 Data processing includes the following.

a) Analyze the curves of pitch angle, indicated airspeed, vertical speed, and elevator deflection over time in the longitudinal control data segment, and provide different... Pitch angle and velocity response characteristics of the state point under different manipulations;

b) Comparative analysis of the control surface deflection and pitch angle curves reveals the response delay characteristics and effects of pitch angle on control surface deflection at different state points. Amplitude characteristics.