TAIPEI (Taiwan News) — Frequent intrusions into Taiwan’s air defense identification zone (ADIZ) by Chinese military aircraft have led the Air Force to budget an extra NT$710.13 million (US$24.24 million) for spare parts and maintenance, reports said Tuesday (April 26).

The Ministry of National Defense recorded 961 such intrusions in 2021, two and a half times as many as the 380 confirmed in 2020, the Liberty Times reported. China is widely believed to be waging a “war of attrition” to test Taiwan’s defense capabilities.

Taipei usually tasks Indigenous Defense Fighters (IDF) and F-16 jets with responding to the ADIZ intrusions, and to a lesser extent its French-built Mirage 2000s. As a result, the needs for spare parts and maintenance for the IDFs and F-16s exceeded the budget originally planned for 2021, leading the military to request additional funds.

Defense reports have called the frequency of Chinese intrusions into the southwestern sector of Taiwan’s ADIZ a threat to the Taiwan-held South China Sea islands of Taiping and Dongsha. China reportedly also sees the area as a gateway to the Pacific for its submarines and believes it needs to defend them from counter-submarine measures by the United States.

While Taiwan has procured 12 P-3C anti-submarine aircraft, it still has only one electronic warfare plane, so it should consider buying Boeing EA-18G Growlers for that purpose, according to a report by one defense think tank.