Airplane Performance on Grass Airfields presents an experiment-based approach to analysis and flight testing of airfield performance on grass runways. It discusses improvements for operational efficiency and safety of these airfields.
The book analyzes the interaction between the landing gear wheels and the surface of a grass runways during both takeoff and landing. Considering the ground performance of an aircraft on a grass runway, the book covers test methods and devices for measuring performance and introduces an information system for the surface condition of grass airfields: GARFIELD. The system is based on a tire-grass interaction model and uses digital soil maps, as well as current meteorological data obtained from a weather server.
The book is intended for researchers and practicing engineers in the fields of aviation and aircraft safety and performance.
Author(s): Jarosław A. Pytka
Publisher: CRC Press
Year: 2023
Language: English
Pages: 151
City: Boca Raton
Cover
Half Title
Title
Copyright
Contents
Preface
Acknowledgments
Author biography
1 Introduction
1.1 Flying on grass airfields
1.2 Grass airfields around the world
1.3 Flying from grass airfields – major problems
1.4 Purpose and scope of the present work
1.5 Summary
References
2 Airfield performance of an airplane – the state-of the-art
2.1 Takeoff and landing
2.1.1 Takeoff and landing distance measurement
2.1.2 Takeoff and landing measurement with the use of GPS and IMU
2.1.3 Liftoff
2.1.4 Airplane stability during takeoff and landing ground roll
2.1.5 Touchdown
2.2 Factors having an effect on airfield performance
2.2.1 Effects of airplane design
2.2.1.1 Powerplant
2.2.1.2 Wing
2.2.1.3 Landing gear
2.2.2 A brief review of airplanes
2.2.2.1 The Wilga DRACO
2.2.2.2 The Scrappy airplane
2.2.3 Airplane certification tests for unpaved runway operation: the Pilatus PC-24
2.3 Effect of airfield conditions
2.3.1 Definitions
2.3.2 Tire–runway interaction
2.3.2.1 Tire–runway friction coefficient
2.3.2.2 Methods for tire–runway friction measurements
2.3.2.3 Rolling resistance coefficient
2.3.2.4 Methods for rolling resistance measurement
2.3.3 Effect of wind
2.3.4 Effect of density altitude
2.4 Conclusion
References
3 Modeling of airfield performance of airplane on a grass runway
3.1 Introduction
3.2 Wheel–soil interaction modeling
3.3 Effect of soil deformation rate
3.4 Effect of vegetation
3.5 Effect of soil moisture
3.6 Synthesis of the model
3.6.1 Influence of the soil substrate of the grass runway
3.6.2 Determination of tractive forces
3.6.3 Modeling the influence of significant factors
3.6.3.1 Soil moisture content
3.6.3.2 Vegetation
3.6.3.3 Wind and density altitude
3.7 Concluding remarks
References
4 Methods
4.1 Grass runway surface characterization methods
4.1.1 Cone penetrometer – a classic terramechanical instrument
4.1.2 TDR – a handheld instrument for soil moisture measurements
4.1.3 Method for characterizing the biomass on the grass runway
4.2 Airplane performance measurement methods – ground testing
4.2.1 Wheel dynamometer for measurements of forces and moments acting on landing gear wheel
4.2.1.1 Introduction
4.2.1.2 Design and development of the wheel dynamometer system
4.2.1.3 Calibration of the sensor
4.2.1.4 Data acquisition and online transfer system
4.2.1.5 Certification of the sensor for ground and flight testing
4.2.2 Methods for determining the rolling resistance and braking friction
4.2.2.1 Tire–runway tester for the measurement of rolling resistance and braking friction
4.2.2.2 Pull test method
4.2.2.3 Instrumented vehicle method
4.3 Airplane performance measurement methods – flight testing
4.3.1 Flight test method for the determination of rolling resistance
4.3.2 Flight test method for the determination of ground reaction under landing gear wheel loading
4.3.3 Ground observer method for takeoff and landing ground distance measurement
4.3.4 Video camera method
4.3.5 Takeoff and landing measurements with the use of AI sensor
4.3.5.1 Introduction
4.3.5.2 Flight phases’ recognition by means of neural network
4.3.5.3 Neural network development
4.3.5.4 Instrumentation
4.3.5.5 Calibration of the method
4.3.5.6 Conclusion
4.3.6 Method for airplane stability during takeoff and landing ground roll
4.3.6.1 The test airplane and the method
4.3.6.2 Flight tests’ campaign
4.4 Conclusion
References
5 Results
5.1 Grass runway characterization
5.1.1 Cone Index
5.1.2 Rolling resistance of grass runway
5.1.3 Effect of soil moisture content upon rolling resistance and braking friction
5.2 Effect of speed on rolling resistance coefficient
5.3 Ground reaction determination under loading of airplane’s wheel at touchdown
5.3.1 Soil stress state under the airplane wheel on touchdown
5.3.2 Orientation of the inertial force and σ1
5.3.3 Concluding remarks
5.4 Results from flight test measurements
5.4.1 Effect of soil strength
5.4.2 Effect of soil moisture
5.4.3 Effect of vegetation
5.4.4 Effect of wind and density altitude
5.4.5 Conclusions
5.5 Airplane stability during takeoff ground roll
5.5.1 Effect of short grass
5.5.2 Effect of tall grass
5.5.3 Conclusion
5.6 Summary
References
6 GARFIELD – an online information system on grassy airfields
6.1 Introduction
6.2 Motivation
6.3 GARFIELD system description
6.4 Methodology
6.4.1 Wheel–grass interaction modeling
6.4.2 GARFIELD software development
6.4.3 System validation
6.5 GRASSTAM – a notice on grass runway surface condition
6.5.1 Introduction
6.5.2 An idea of the GRASSTAM
6.5.3 Method of grass runway assessment
6.6 Conclusion
References
Index
