Consideration and validation of flight control requirements under all engine failure conditions for MEA

This paper aims to propose a strategy for the flight control of quad-rotors under single rotor failure conditions. The proposed control strategy consists of two stages—fault detection (FD) and fault tolerant control (FTC). A dual observer-based strategy for FD and fault estimation is developed. With the combination of the results from both observers, the decision making in whether a fault actually happened or the observed anomaly was caused by an external disturbance could be distinguished. Following the FD result, a control strategy for normal flight, as well as the abnormal one, is presented. The FTC considers a real-time coordinate transformation scheme to manipulate the target angles for the quad-rotor to follow a prescribed trajectory. When a rotor fault happens, it is going to be detected by the dual observers and then the FTC is activated to stabilize the system such that the trajectory following task can still be fulfilled. Furthermore, in order to achieve robust flight in the presence of external wind perturbation, the sliding mode control (SMC) theory is further integrated. Simulations illustrate the effectiveness and feasibility of the proposed method.

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Robust Mechatronic Actuation System for UAV Primary Flight Controls

Volume 1: Advances in Aerospace Technology ◽

10.1115/imece2012-85339 ◽

2012 ◽

Author(s):

Davide Ferrara ◽

Giovanni Jacazio ◽

Andrea Mornacchi ◽

Massimo Sorli

Keyword(s):

Flight Control ◽

Position Control ◽

Control Surface ◽

Mechatronic System ◽

Research Activity ◽

Actuation System ◽

Flight Controls ◽

High Integrity ◽

And Performance ◽

Failure Conditions

The paper describes the initial results of a research activity aimed at developing a high integrity mechatronic system for UAVs primary flight controls able to ensure the necessary flight safety and to enhance the system availability by implementing appropriate prognostic functions. In this system a flight control surface is driven by two parallel rollerscrews, on their turn driven by brushless motors equipped with gearhead and clutch; the motors electric drives are controlled by dual redundant electronic units performing closed loop position control as a function of the commands received from the flight control computer. Provisions are taken in the motor drives to provide damping in the event of simultaneous failure of both actuators. The electronic units perform control, diagnosis and prognosis of the actuation system and mutually exchange data via a cross channel data link. System prognosis is made by dedicated algorithms processing the control and feedback signals obtained in flight and during preflight checks. As a whole, a smart mechatronic system is obtained providing high integrity control of an aerodynamic surface with dual mechanical link, dual power source and quadruplex control, similarly to a fly-by-wire hydraulic flight control. The paper first addresses the critical design issues associated with the electromechanical actuation of flight control surfaces, briefly reviews alternative solutions proposed for jam-tolerant electromechanical actuators, then outlines configuration, characteristics and performance of the mechatronic actuation system, and presents a summary of its behaviour under normal, degraded, fault developing and failure conditions.

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A Optimization Algorithm of Obstacle Limit Takeoff Weight

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.505-506.370 ◽

2014 ◽

Vol 505-506 ◽

pp. 370-374

Author(s):

Hong Ying Chen ◽

Wen Tian Luo

Keyword(s):

Optimization Algorithm ◽

Flight Path ◽

Simulation Results ◽

Engine Failure ◽

Failure Conditions

This method is explained and demonstrated how to calculate obstacle limit takeoff weight. According regulation requirement, under an engine failure conditions, it needs to consider the takeoff flight path different segments which can clear all obstacles [. In this paper, take-off gross flight path and net flight path are analyzed, and taking an aircraft for example, obstacle limit takeoff weight are calculated, Simulation results show the feasibility of optimization algorithm.

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ACOUSTIC EXPRESS METHOD FOR MEASURING ELASTIC METAL CONSTANTS OF HIGH-LOADED CONSTRUCTIONS WORKING IN EXTREME CONDITIONS. PART 1

Kontrol Diagnostika ◽

10.14489/td.2020.06.pp.046-063 ◽

2020 ◽

pp. 46-63

Author(s):

V. T. Bobrov ◽

V. M. Bobrenko ◽

A. V. Gulshin

Keyword(s):

Flight Control ◽

Negative Impact ◽

Fatigue Cracks ◽

Corrosion Damage ◽

Resource Assessment ◽

Navigation Systems ◽

Space Technology ◽

Aircraft Fuselage ◽

Engine Failure ◽

Critical Components

A review of contingencies related to the failure of potentially hazardous equipment of the aviation and space-rocket complexes showed that they lead to explosions, fires, deaths and destruction of infrastructure. The causes of accidents and disasters are errors in the selection of technical solutions and materials during design, imperfection of algorithms and software for flight control systems, malfunctions in on-board computers and security systems, navigation systems, engine failure, defects in components and assemblies. Examples of accidents and disasters related to technical failures leading to a violation of the tightness of the aircraft fuselage and depressurization of spacecraft are given. It is shown that the main types of damage to the units are corrosion damage, fatigue and metal wear. The conclusion is made about the negative impact of the “human factor” regarding the adoption of erroneous decisions, failure to comply with regulatory requirements and actions in extreme situations. There is a risk of fatigue cracks and degradation of the properties of stringer metal, landing gear struts, wing tail trim, fuel tanks, engine pylon flanges, and imperfect methods, equipment, and technology for monitoring fatigue defects of critical components and mechanisms of aircraft, helicopters, and space systems. It is shown that modern achievements are poorly used in research and development of physical methods and diagnostics of elastic constants of metals working under high pressure, their changes in conditions of wide temperature drops, cosmic vacuum, vibration and other influences. It is proposed to combine efforts with scientists and experts in the field of strength, resource assessment and operational safety of aviation and space technology.

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Automation Surprise

Aviation Psychology and Applied Human Factors ◽

10.1027/2192-0923/a000113 ◽

2017 ◽

Vol 7 (1) ◽

pp. 28-41 ◽

Cited By ~ 4

Author(s):

Robert J. de Boer ◽

Karel Hurts

Keyword(s):

Flight Control ◽

Representative Sample ◽

Aviation Safety ◽

Control Mode ◽

Cognitive Errors ◽

Laboratory Studies ◽

Airline Pilots ◽

Flight Operations ◽

Widespread Phenomenon ◽

Few Data

Abstract. Automation surprise (AS) has often been associated with aviation safety incidents. Although numerous laboratory studies have been conducted, few data are available from routine flight operations. A survey among a representative sample of 200 Dutch airline pilots was used to determine the prevalence of AS and the severity of its consequences, and to test some of the factors leading to AS. Results show that AS is a relatively widespread phenomenon that occurs three times per year per pilot on average but rarely has serious consequences. In less than 10% of the AS cases that were reviewed, an undesired aircraft state was induced. Reportable occurrences are estimated to occur only once every 1–3 years per pilot. Factors leading to a higher prevalence of AS include less flying experience, increasing complexity of the flight control mode, and flight duty periods of over 8 hr. It is concluded that AS is a manifestation of system and interface complexity rather than cognitive errors.

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An Alternative Method for Identifying a Failed Engine in Twin-Engine Propeller Aircraft

Aviation Psychology and Applied Human Factors ◽

10.1027/2192-0923/a000195 ◽

2020 ◽

Vol 10 (2) ◽

pp. 103-111

Author(s):

Andrey K. Babin ◽

Andrew R. Dattel ◽

Margaret F. Klemm

Keyword(s):

Human Error ◽

Flight Simulator ◽

Traditional Group ◽

Aircraft Accidents ◽

Alternative Method ◽

Indicator Group ◽

Group A ◽

The Dead ◽

Engine Failure ◽

And Performance

Abstract. Twin-engine propeller aircraft accidents occur due to mechanical reasons as well as human error, such as misidentifying a failed engine. This paper proposes a visual indicator as an alternative method to the dead leg–dead engine procedure to identify a failed engine. In total, 50 pilots without a multi-engine rating were randomly assigned to a traditional (dead leg–dead engine) or an alternative (visual indicator) group. Participants performed three takeoffs in a flight simulator with a simulated engine failure after rotation. Participants in the alternative group identified the failed engine faster than the traditional group. A visual indicator may improve pilot accuracy and performance during engine-out emergencies and is recommended as a possible alternative for twin-engine propeller aircraft.

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