In order to effectively prevent the occurrence of civil aviation maintenance related events, a sample of 2 687 voluntary reports from the US Aviation Safety Reporting System (ASRS) database (2001-2023) was examined. Fourteen risk factors, including work environment and human factors, were analyzed using CiteSpace. Strong couplings between these factors were identified through UCINET and Gephi. The results show the following findings: Among the nine single risk factors, key risks are identified as landing gear system malfunctions, poor lighting, and rain (with frequencies of 103, 64, and 45, respectively). Among the five coupled risk factors, key risks are found to be airframe maintenance, communication breakdown, and human factors (with co-occurrence frequencies of 1 646, 1 448, and 1 206, respectively). The analysis of all risk factor couplings reveals that the strongest coupling exists between airframe maintenance and powerplant maintenance (with a weight value of 3 568). Additionally, a significant coupling relationship is observed between procedures and improper landing gear system operations (with a weight value of 118).