High Angle of Attack Flight of a Subscale Aerobatic Aircraft

Abstract

This paper describes initial high angle of attack flight testing performed by a subscale aerobatic aircraft. A 35% scale, 2.6 m (102 in) wingspan Sukhoi 29 S electric aircraft, the UIUC Subscale Sukhoi, was developed and used for this research. The aircraft was instrumented with a custom 100 Hz sensor data acquisition system, which had been previously developed and tested. The aircraft was flown through several stalls and descending harrier maneuvers during which flight data was recorded by the sensor data acquisition system. The flight data recorded during the maneuvers was used to produce time histories of aircraft state and aerodynamic coefficients. A brief literature review of similar aerobatic unmanned aircraft used for high angle of attack research is first presented. Then a background and a description of the development of the aircraft are given along with specifications. Next, information about data analysis methods used to analyze flight test data is given. After that, initial test flight results are presented, including flight path trajectory plots, time histories and aircraft aerodynamic coefficient data. Finally a list of proposed future work is given.

Flight Data Acquisition Platform Development, Integration, and Operation on Small- to Medium-Sized Unmanned Aircraft

“…38 Then in 2013, the Flight Control Systems Laboratory at West Virginia University developed a Gen-V avionics system in order to support their Phastball research into simplifying and reducing the cost of flight testing. [39][40][41] Afterwards in 2013, researchers at the University of Illinois developed the SDAC data acquisition for subscale aerodynamics flight testing; 5,[42][43][44] this system was the basis for development of the Al Volo FDAQ and FC+DAQ. 34 Then in 2014, Stockton and Vuppala at Oklahoma State University developed a flight control system and hardware in the loop testing environment to demonstrate new control strategies.…”

“…3, will be used as example. The aircraft used for demonstration will include the UIUC Subscale Sukhoi , 5 the UIUC GA-USTAR , 85 and the UIUC Solar Flyer , 60,86 all of which are distinctly different types of aircraft and have different types of integration and operation challenges. Photos of the aircraft are shown below.…”

“…In just the past several years, along with the uptrend in UAV use, there has been an increase in the research to evaluate and improve aircraft performance and flight characteristics. For example, significant effort has been put into studying their aerodynamic qualities, 1,2 especially in high angle-of-attack conditions, [3][4][5] as well as the development of new control algorithms. [6][7][8][9][10][11] In addition, unmanned aircraft are often used as low-cost stand-ins for experiments that are too risky or costly to perform on their full scale counterparts.…”

Propulsion System Testing for a Long-Endurance Solar-Powered Unmanned Aircraft

“…size, compatibility, price, and availability) as well as previous experience integrating data acquisition systems into aircraft (e.g. interfacing with ESC), 4,19,[27][28][29][30] a desired acquisition rate is in the order of 100 to 400 Hz, with preference towards to the higher end.…”

A Rolling Rig for Propeller Performance Testing

“…The concept of the rolling rig began due to a lack of performance data for the Mejzlik 27 x 12 TH propeller, used on both the UIUC AeroTestbed 1 and the UIUC Subscale Sukhoi. 2 The importance of attaining propeller performance data follows that in order to find the aerodynamic coefficients while the motor is on, the thrust and torque generated by the propeller must be known at all times. More specifically, the aerodynamic coefficients are calculated from the aerodynamics forces and moments, which are found by subtracting the propeller force and moment, along with the gravitational force, from the total forces and moments applied to the aircraft (these are derived from the inertial measurement unit located on the aircraft).…”