Identification of damage and corrosion effect in aging aircraft data transmission lines

• Published in: Engineering failure analysis Vol. 157; p. 107887
• Main Authors: Valiev, Saidanvar, Okafor, Anthony C., Prakash Hungund, Abhishek, Huang, Jie
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01-03-2024
• Subjects: Accelerated corrosion testing; Aging aircraft maintenance; Aircraft data transmission line; Coaxial cable; Damage and corrosion detection; Failure modes in ADTL; Nondestructive evaluation; Signal reflection and transmission; Vector Network Analyzer; Nondestructive evaluation; Aircraft data transmission line; Accelerated corrosion testing; Coaxial cable; Damage and corrosion detection; Vector Network Analyzer; Failure modes in ADTL; Aging aircraft maintenance; Signal reflection and transmission
• ISSN: 1350-6307; 1873-1961
• DOI: 10.1016/j.engfailanal.2023.107887

•Reflected signal (S11) peak successfully detected EOC, ECC, & EECC damage in ADTL.•Corrosion on damaged ADTL was studied using change in magnitude & FW3QM of S11 peak.•FW3QM of S11 peak from damage was used to track corrosion propagation in ADTL.•Deeper damage in ADTL cause additional disturbance in the passing through signal.•S11 shape of EECC cable represent antenna signal in equally spaced reflected peaks.
Corrosion in aircraft structures and systems persists to pose significant problem in the aircraft industry. It affects both the aircraft structures and all the wiring systems including data transmission lines at the points of mechanical damage (missing or damaged insulation and jacket materials) and connections. Reliability of data transmission through aircraft data transmission lines (ATDL) is essential for maintaining performance capability and safety of flights. Unfortunately, there is no existing method for detecting corrosion and predicting its effect for wiring systems including ADTL. Detecting corrosion and predicting its effect on time would prevent unexpected system failures and catastrophes. This paper presents novel experimental method that has been employed, for the first time, to detect and study the effect of localized corrosion process on reflected and transmitted power signals passing through locally corroded ADTL with mechanically induced damage. ADTL with three types of induced damage were corroded in a Q-Fog cyclic accelerated corrosion chamber for over 14 weeks (2352 h) using ASTM G85-A5 Prohesion test that resembles the environment of aircraft operation. Cable specimens were taken out every week and investigated by measuring transmitted and reflected power signals passing through the corroded ADTL using Vector Network Analyzer (VNA), where signals from 0 to 6 GHz were swept into the ADTL. Reflected and transmitted power signals (S11 and S21 respectively) were acquired in time domain and processed in MATLAB. Analysis of results show that corrosion effect is not arbitrary and can be tracked over time and predicted. Reflected signal peak width changed over time of corrosion exposure and is proportional to corrosion propagation width inside the ADTL. It is also observed that corrosion induced extra distortion of signals passing through the corroded damage region. The results are very promising for detecting corrosion and predicting its effect in ADTL.