Sent_en: 2zh Both the NTSB and the AAIB also sent letters to the US Federal Aviation Administration and the European Aviation Safety Agency requesting the installment of the modified component be mandatory.
Sent_yy: 国家运输安全委员会和航空事故调查局同时又向美国联邦航空管理局和欧洲航空安全局致函，要求强制性安装改进后的部件。