Aircraft Fault Diagnosis Prognostics and Health

Abstract-A flight recorder is very important onboard flight safety
equipment, ant it plays a very important role in aircraft fault diagnosis prognostics and health management(AFDPAHM). It is thought that there are three methods when a flight recorder is applied in AFDPAHM after the composition and characteristics of flight reorder information have been studied: the first is analytical redundancy ones, the second is parameter trend forecasting ones, and the third is fault tree ones etc. The application of the three methods in AFDPAHM has been discussed in detail in this paper. These three methods have their advantages and disadvantages respectively. When the mathematical model of a subsystem or device is easy to be set up, the analytical redundancy method can be applied. When the failure mechanism of the subsystem or device is very complicated and it is very difficult to set up its mathematical model, the parameter trend predication can be used. When the logic relationship of internal structure of the subsystem or device is very clear and the failure probability of every component can be obtained, then the fault tree method is available.
II.
COMPOSITION AND CHARACTERISTICS OF FLIGHT REORDER INFORMATION
Keywords- flight recorder; analytical redundancy; parameter trend predication; fault tree
Aircraft Fault Diagnosis Prognostics and Health Management Based on Flight Recorder
Chaojiang Hu
Beijing Aeronautical Technology Research Center Beijing, China Email: Hu_chaojiang@163.com
I.
INTRODUCTION
ຫໍສະໝຸດ Baidu
Aircraft fault diagnosis prognostics and health management (AFDPAHM) plays a very important role in improving flight safety, reducing maintenance downtime and lowering cost of aircraft maintenance and use, so a lot of money and manpower have been invested for development of the technology in many developed country in aviation industry and advanced AFDPAHM are applied in many advanced airliner such as Boeing 787,Airbus 380, and some new generation fighters such as F-22 and F-35[1][2]. In contrast, some old aircraft in AFDPAHM is still very backward. So it is necessary to take comprehensive measures to strengthen AFDPAHM research about these aircraft. A flight recorder is very important onboard flight safety equipment, ant it is not only applied in flight accident investigation, but also plays a very important role in AFDPAHM. But the application of flight recorder information in AFDPAHM is hindered seriously because of no in-depth study in this field. So it is very necessary to research sufficiently how to apply flight recorder information in AFDPAHM, and improve aircraft flight safety level.
978-1-4577-1911-0/12/$26.00 ©2012 IEEE
MU3211
2012 Prognostics & System Health Management Conference (PHM-2012 Beijing)
Flight recorders have been installed in aircraft sincel950s. Only five parameters were recorded in initial flight recorders, i.e. flight velocity, flight altitude, heading direction, vertical acceleration and time. The flight path of an aircraft can be reconstructed with these parameters. Then the parameters in a flight recorder have been increasing with the development of aircraft in order to meet requirement of flight accident investigation very well. The 78 types of parameters should be recorded according to the ED-112 promulgated by the European Organization for Civil Aviation Equipment in 2003. The parameters which must be recorded in an airliner flight recorder are usually over 170 if all these 78 types of parameters are recorded. In fact, the number of parameters recorded in almost all airliner recorders is more than the required number of parameters required by ED-112[3]. The number of parameters recorded in Boeing 737 is over 300, and even more than 2000 in Boeing 787. The parameters in flight recorder are usually aircraft flight dynamics system ones such as flight height, flight velocity, pitch/roll/heading angle etc; control system ones such as stick /pedal displacement, horizontal taiVaileronirudder position etc; engine system ones such as thrust, high and low-pressure rotor speed, throttle lever position, vibration, lubricating oil pressure, nozzle position etc; and also navigation system ones, hydraulic system ones, fuel system ones, avionics ones, landing gear system ones, alarm systems ones etc. It is necessary to apply sufficiently flight recorder information in AFDPAHM because there is a great amount of information about aircraft fault in flight recorder. It can be known after flight recorder information has been analyzed that different AFDPAHM method must be taken based on the information feature of different sub-system or equipment in flight recorder because the principle and failure mechanism of these sub-systems or equipments are different. The following methods to diagnosis and predict fault in aircraft with fight recorder information are put forward after composition and characteristics of flight recorder information have been studied and analyzed, i.e. analytical redundancy ones[4], parameter trend prediction ones[5] and fault tree ones [6]etc.