（法新社洛杉矶6日电） 美国联合航空公司今天整个系统发生问题，导致许多航班停飞，包括纽瓦克、芝加哥、旧金山和休士顿等主要机场枢纽都受到影响，数以千计乘客行程延误。

The outage, beginning just after 6 p.m. Eastern time (2200 GMT), prompted ground stops at several major United Airlines hub airports, including Chicago, Houston, Denver, Newark and San Francisco, ...