Medium Altitude Long Endurance Research Articles

UAS Integration into the NAS: An Examination of Baseline Compliance in the Current Airspace System

As a result of the FAA Modernization and Reform Act of 2012, Unmanned Aerial Systems (UAS) are expected to be integrated into the National Airspace System (NAS) by 2015. Several human factors challenges need to be addressed before UAS can safely and routinely fly in the NAS with manned aircraft. Perhaps the most significant challenge is for the UAS to be non-disruptive to the air traffic management system. Another human factors challenge is how to provide UAS pilots with intuitive traffic information in order to support situation awareness (SA) of their airspace environment as well as a see-and-avoid capability comparable to manned aircraft so that a UAS pilot could safely maneuver the aircraft to maintain separation and collision avoidance if necessary. A simulation experiment was conducted to examine baseline compliance of UAS operations in the current airspace system. Researchers also examined the effects of introducing a Cockpit Situation Display (CSD) into a UAS Ground Control Station (GCS) on UAS pilot performance, workload and situation awareness while flying in a positively controlled sector. Pilots were tasked with conducting a highway patrol police mission with a Medium Altitude Long Endurance (MALE) UAS in L.A. Center airspace with two mission objectives: 1) to reroute the UAS when issued new instructions from their commander, and 2) to communicate with Air Traffic Control (ATC) to negotiate flight plan changes and respond to vectoring and altitude change instructions. Objective aircraft separation data, workload ratings, SA data, and subjective ratings regarding UAS operations in the NAS were collected. Results indicate that UAS pilots were able to comply appropriately with ATC instructions. In addition, the introduction of the CSD improved pilot SA and reduced workload associated with UAS and ATC interactions.

Design of all electric secondary power system for future advanced medium altitude long endurance unmanned aerial vehicles

System for unmanned aerial vehicles (UAV) advanced alternative energy (SAvE) is a research project funded in 2007 by Piemonte Regional Government, Italy, and assigned to Politecnico di Torino and Alenia Aeronautica. Aim of the project is the study of new, more efficient, more effective, and more environmentally friendly on board systems for future advanced UAV, particularly for future advanced medium altitude long endurance (MALE) UAVs. This article deals with the analysis and design of the all electric secondary power system of a future advanced MALE UAV that is considered as ‘reference aircraft’. After a thorough trade-off analysis of different configurations of the secondary power system, the hybrid fuel cells configuration, characterized by starter/generators, fuel cells, and traditional and innovative batteries, has been selected as the most promising. Detailed investigations to find the best way to apportion the supply of secondary power, considering the various power sources (starter/generators, batteries, and fuel cells) in the different modes of operations, have been performed thanks to an integrated simulation environment, where physical, functional, and mission scenario simulations continuously exchange data and results.

Modeling and Simulation Enabled UAV Electrical Power System Design

With the diversity of mission capability and the associated requirement for more advanced technologies, designing modern unmanned aerial vehicle (UAV) systems is an especially challenging task. In particular, the increasing reliance on the electrical power system for delivering key aircraft functions, both electrical and mechanical, requires that a systems-approach be employed in their development. A key factor in this process is the use of modeling and simulation to inform upon critical design choices made. However, effective systems-level simulation of complex UAV power systems presents many challenges, which must be addressed to maximize the value of such methods. This paper presents the initial stages of a power system design process for a medium altitude long endurance (MALE) UAV focusing particularly on the development of three full candidate architecture models and associated technologies. The unique challenges faced in developing such a suite of models and their ultimate role in the design process is explored, with case studies presented to reinforce key points. The role of the developed models in supporting the design process is then discussed.

Display Type Effects in Military Operational Tasks Using UAV Video Images: Comparison between Two Types of UAV Feeds Mini and MALE (Medium-Altitude-Long-Endurance) UAVs

The increased usage of new technologies in combat requires measuring tools and guidelines that will enable maximal compatibility between technology and users' needs. Specifically, using video feeds retrieved by dismounted soldiers from different types of unmanned aerial vehicles (UAVs) may affect the efficiency level of using such machines. This work follows our previous studies on the type (e.g. size) of displays required by dismounted soldiers to process video feed from UAVs. Twenty two former infantry soldiers with no experience using UAV video feed participated. Three displays were examined using two video feed types (MALE and Mini UAVs) in four different task types (description, direction, orientation, and response). Performance and subjective data were collected. Results show no effect (only some trends) for display type, but significant effect for the interaction between video feed type and task type and display type.

MALE UAV design of an increased reliability level

PurposeThis study seeks to present the initial requirements for medium altitude long endurance (MALE) UAV design of an increased reliability.Design/methodology/approachShows and describes the successive design phases of PW‐103 MALE UAV.FindingsThe analysis of the performances of the PW‐103 UAV, powered by either a main or an auxiliary engine, demonstrated that auxiliary power unit improved flight safety significantly.Originality/valueSuccessive MALE UAV configurations developed in the design process were aerodynamically more efficient than their predecessors.

Graduate-level design education, based on flight demonstrator projects

The College of Aeronautics (CoA) at Cranfield University believes that the best way of teaching design is for the students to learn design by doing it, in a structured manner. It also believes in the maxim – “the devil is in the detail” and that a design is only complete when it has been built, flown and certificated. Designers need to be aware of, and experienced in, all of the intermediate stages between concept design and certification. They also need to be taught to function as members of group design teams, because that is the usual way that Industry works. All of these factors led to the establishment of a full-time Masters programme in Aerospace Vehicle Design, the focus of which is the Group Design Project (GDP). This philosophy was proved to be successful over many years and was continued and expanded in the design of the Masters course in Aircraft Engineering – the subject of this paper. This programme is a three-year part-time M.Sc. course, which comprises the same major elements as the full-time course. The students attend lecture modules, perform a piece of individual research and work on a GDP. It was this last element that particularly attracted the launch and predominant customer for the course, the then Military Aircraft Division of British Aerospace (BAe). BAe like the basic philosophy of teaching the design process by placing someone in a project group with an individual responsibility but having to cater for the needs of the group and project as a whole. In February 1995 the Aircraft Engineering course was launched with 15 students, who began the first intake, working on major modifications to the CoA's A1 Aerobatic aircraft, which itself resulted from work of former students. The GDP on the full-time course in Aerospace Vehicle Design concentrates on the preliminary and detail design of a whole aircraft, which has been previously defined in terms of basic geometry, mass, performance, characteristics etc. by staff. However, BAe and Cranfield wished to address a greater extent of the full-design process, as mentioned above. In this way the students would, in the space of three years, be given first-hand experience of a much wider extent of an aerospace project than could ever be the case whilst working on major aircraft projects in a manufacturing company. This paper will give details of the Aircraft Engineering teaching programme and describe the first GDP, a major modification programme and flight of the Cranfield A1 Aerobatic Aircraft. The students were set the task of modifying the existing single seat aircraft to a two-seat configuration with performance similar or better than that of the existing aircraft, despite the weight increase of a second pilot. At approximately one year into the project, a joint BAe/CoA decision was made to progress the project to completion with an `affordable’ set of modifications, providing the basic two seat capability, increased endurance, and approaching the desired performance. The aircraft was modified by BAe and CoA personnel and successfully completed its official first flight on the 30th September 1998 at Cranfield's own airfield, flown by its own Chief Test Pilot, thus completing the first of the 5 GDPs described in this paper. Information will also be given of progress being made on more recent intakes of students. The subject for intake 2 was further modifications to the A1 to further improve its lateral manoeuvrability by means of a new composite vertical stabiliser and rudder. Intakes 3 and 4 are capitalising on Cranfield's extensive expertise in the design and flight-testing of small UAV's, to develop jet-powered UAVs to act as flight-test demonstrators for unstable aircraft with diamond and blended-wing-body configurations. These will contribute significantly to Cranfield's extensive research programmes in these areas. The fifth intake has started to design a medium altitude, long endurance (MALE) UAV which will provide a platform for Cranfield's, and other researchers in the fields of remote sensing and payloads for Micro-Satellites. Ref. [4] gives more details of the 1st and 3rd GDPs. These are exciting, but challenging projects which continue to develop the best of design teaching and relevant applied research. Fig. 1 shows how the above 5 GDPs are integrated into Cranfield's strategic aircraft configuration demonstrator programme. It includes a large number of Ph.D. studies, full-time and part-time GDPs and inputs from government-funded programmes.