Brian A. Kish

Autonomous aerial refueling based on the tanker reference frame

An aircraft formation autopilot is designed for flight test to demonstrate autonomous aerial refueling. The controller requirements are stated, and models for the lead and wing aircraft are outlined and stabilized. Control laws are developed for the model, and four frames of reference are investigated for optimal control. Next, a simulation is constructed with modeled disturbances to produce the real-time inputs that will be available to the controller. Results from simulations of the controller are presented and assessed, including an exploration of sensitivity and robustness. Finally, results are presented from a limited flight test investigation conducted with a formation of an Air Force C-12 and a variable stability Learjet LJ-25, flown by the controller. Fully autonomous aerial refueling maneuvers were successfully demonstrated in both level and turning flight. Finally, conclusions and lessons learned from the flight test and the controller development are presented

Optimal Control of Sensor Threshold for Autonomous Wide Area Search Munitions

The optimal employment of autonomous wide area search munitions is addressed. The scenario considered involves an airborne munition searching a battle space for stationary targets in the presence of false targets. Targets are modelled with uniform, Poisson, and normal distributions. False targets are modelled with Poisson distributions. All relevant parameters can be extracted from intelligence information on the enemy’s order of battle and the sensor performance specification. Analytic weapon effectiveness measures are derived using applied probability theory. The effectiveness measures derived in this paper handle time-varying parameters which characterize the battle space environment and the performance of the munition’s sensor. This allows the formulation and solution of optimization problems that maximize the probability of a target attack while at the same time constraining the probability of a false target attack. Optimal schedules for controlling the sensor threshold during the flight are derived and compared to the optimal constant-threshold results. An increase in weapon effectiveness is demonstrated when the sensor threshold is dynamically controlled during the flight.

Affordable moving surface target engagement

This paper presents the results of the Defense Advanced Research Project Agency-funded Affordable Moving Surface Target Engagement program. The overall objective was to develop affordable technologies to engage moving surface targets such as tanks, tactical ballistic missile transporters and small boats. The Northrop Grumman team used moving target indicator sensors on multiple aircraft to individually track moving ground targets. Report data were shared between sensor platforms to form an accurate multi-laterated track. These highly accurate track data were transmitted to a Lockheed Martin Precision Direct Attack Munition, which was released from an F-16 aircraft and guided by an inertial navigation system with updates from a differentially-corrected carrier-phase Global Positioning System receiver. The sensor platforms provided continuous target location updates to the weapon during flight. The final demonstration flight was completely successful. The Northrop Grumman high update rate, multilaterated moving target indicator concept scored a direct hit on a remote controlled van moving at 25 miles per hour.

Wing Bug: A portable, low-cost flight test instrumentation system

The WingBug was an innovative concept by Straight & Level Technologies to measure airspeed, altitude, temperature, Euler angles, angular rates, and acceleration information. The unit was portable, self-powered, streamed data via WiFi to any tablet or smart phone in the cockpit, and cost less than

A new temperature correction algorithm for FAA engine cooling tests

1000. It measured 8″×3″×3″, weighed 6 ounces, and used a GoPro mount to attach externally to any aircraft. This paper covers results from the initial flight test program flown at Florida Institute of Technology in 2016. The WingBug was flown on a Piper Warrior. Data from the WingBug were compared to “truth” data from the Piper Warrior. Test points were limited to static points (e.g. constant bank-angle turns). An evaluation of the tablet display was also performed. Overall, the prototype WingBug shows promising potential as a flight test system or primary flight reference system for home-built aircraft. The recommendations provided can be used by Straight & Level Technologies to further improve their system.

JSTARS demonstrations in real-world environments

An analysis of the Federal Aviation Administration (FAA) certification requirements has revealed a potential error in the temperature correction formula the FAA requires manufacturers to use to process engine cooling data for compliance with Part 23 of Title 14 of the Code of Federal Regulations (14 CFR Part 23). The FAA engine cooling performance temperature correction formula, which predicts the critical temperature of engine components, was quantitatively evaluated using data acquired with a single-engine aircraft powered by a normally aspirated, air-cooled, reciprocating engine. Previous research has failed to analyze the effect ambient air temperature has on oil temperature and has failed to propose a more accurate model for predicting critical cylinder head and oil temperature. Engine cylinder head and oil temperature data were acquired during FAA-defined, cooling-performance climbs performed on three days with different ambient air temperatures. The acquired data revealed the FAA correction formula, when applied to cylinder head temperature, did not correct data to the most critical test condition, potentially leaving certified aircraft vulnerable to overheating. The acquired data showed the FAA correction formula, when applied to oil temperature, worked fairly well. Nonetheless, there was room for improvement. Thus, new temperature correction formulas were developed to predict both critical engine cylinder head and oil temperature for compliance with 14 CFR Part 23. The FAA can evaluate these correction formulas for use in 14 CFR Part 23 to ensure engine cooling performance is properly tested and general aviation aircraft remain safe from overheating.

Air-to-Air Evaluation of an Amplified 802.11b Network

The Joint Strategic Target Attack Radar System (JSTARS) has a long history of sending its development test aircraft into real-world, operational events. Typically, weapon systems are not tasked for real-world events until their test programs are complete. Intelligence, surveillance, and reconnaissance platforms like JSTARS are sometimes allowed to participate from afar in real-world events because they do not interfere with operations, yet they can provide needed targeting data. This paper presents the results of demonstrations conducted on the JSTARS test aircraft in 2010 and 2011. The prototype systems had not been fully tested nor approved as funded programs. The demonstrations proved JSTARS capabilities apply to more than just military operations. JSTARS capabilities can also be used for disaster relief, homeland security, and law enforcement. This paper also identifies the typical challenges of a demonstration and provides the steps needed for success.

Test Management Projects from Test Pilot School Classes 06B and 07A

Students at the United States Air Force Test Pilot School, successfully completed a limited evaluation of an 802.11b air-to-air WiFi data link between two C-12C test aircraft. The test team determined the maximum range capability for 1 megabit per second (Mbps) and 11 Mbps transmissions over the WiFi data link when transmitting at 1 or 5 Watts of amplifier power, corresponding to 0.32 and 1.58 Watts of effective isotropic radiated power, respectively. Diagnostic and performance statistic software on laptops were used to gather the data rate and performance statistics in flight, while post flight analysis was conducted to retrieve the data link range statistics. The flight test results closely matched the predicted maximum ranges found using an RF link prediction model, accounting for cabling losses, amplification, antenna gain, free space losses, amplifier receive gain, and the published SecNetllreg receiver sensitivity. Increased reception range could have been achieved using lower loss RF cabling and placing the amplifier closer the antenna. Of the available configurations tested (ad hoc, infrastructure and bridge), ad hoc was found the most reliable. The test team also demonstrated the capability of transmitting and receiving text files, still images, pre-recorded video, and streaming, live webcam video between the two test aircraft.

In-flight Evaluation of an Amplified 802.1lb Network

*† ‡ § ** The United States Air Force Test Pilot School uses real-world Test Management Projects for its capstone event. Each class is divided into four groups of 4-6 students. Each group is given a unique project from a real DoD customer and asked to plan, schedule, execute, and report on the project. Projects from TPS Class 06B included a new trailing cone system for use on the F-16, performance testing of the T-38A at 45 percent flaps, drag determination of the L-23 Super Blanik sailplane while performing dynamic soaring techniques, and an air-to-air test of an amplified WiFi data link. Projects from TPS Class 07A included a handling qualities evaluation of a supersonic tailless air vehicle model, a validation of monocular optical inertial navigation, an evaluation of a velocity estimation algorithm, and an evaluation of a laser-based infrared countermeasure. Each project involved cutting-edge research.

Pitot static testing of the RU-38A

Students at the United States Air Force Test Pilot School accomplished flight testing of an 802.11b air-to-ground wireless datalink between a C-12C and a ground station12. A total of 17.6 hours were flown on seven flight test sorties from 10 April to 2 May 2006. The system under test consisted of S-band antennas on the aircraft and at the ground station, radio frequency signal amplifiers for the antennas, an electronic display unit for the pilots, a laptop PC connected to the aircraft station, a tablet PC connected to the ground station, and two Ciscoreg Aironet 1200 Wireless access points connected to the ground and aircraft amplifiers. This test program demonstrated the 802.11b wireless datalink reception range when transmitting at 4 Watts effective isotropic radiated power. The test program demonstrated the utility of transmitting high resolution imagery and streaming video across the datalink within specific signal-to-noise ranges. The test team also evaluated the utility of high resolution imagery and streaming video transmitted across the datalink. The test configuration identified deficiencies in operating system employment during high resolution imagery and streaming video transmissions. However, the system demonstrated the bandwidth and ground distance/altitude capabilities of the 802.11b wireless network. The 802.11b wireless air-to-ground datalink performance was satisfactory in its tested configuration for transmitting high resolution imagery. However, it was not adequate in its tested configuration to provide reliable time-critical targeting streaming video. The datalink reception envelope provided operationally useful data ranges, with low data rate connections established between the aircraft and ground station at ground distances greater than 15 nautical miles for the tested altitudes.