BLOOMBERG NEWS United Airlines grounded dozens of its Boeing 777s yesterday.

Inspections cancel Boeing 777 flights

Two Hawaii flights were affected

CHICAGO » United Airlines temporarily grounded 11 percent of its fleet and canceled 31 flights yesterday while it tested dozens of Boeing 777s to make sure components of a cargo fire suppression system were operating effectively.

Delays were reported in Japan and Hawaii yesterday and the airline warned passengers to be prepared for other delays and cancellations as it proceeded with the inspections. Medina said 31 of 84 scheduled 777 flights had been canceled.

United canceled two Kona flights yesterday. Planes going from Kona to Chicago and Maui to Kona were impacted by the inspections, said Jeff Kovik, a spokesman for United Airlines.

"We're going to continue to get all of our customers to their destinations as quickly as possible," Kovik said.

The inspections are the latest to affect the U.S. airline industry and its passengers, roiled by a series of similar moves in recent weeks as carriers review their maintenance records in an atmosphere of increased regulatory scrutiny.

The Chicago-based airline said testing would be done on 52 777s over a period of 36 hours. Spokeswoman Jean Medina said 22 planes had been inspected and cleared to fly by late morning.

The carrier has about 460 aircraft.

United, a subsidiary of UAL Corp., said a review of maintenance records showed a test on one of five bottles in the fire suppression system hadn't been performed. The airline alerted authorities.

The planes, which have a so-called "intuitive" self-diagnostic system that would have detected any malfunction with the fire suppression system, mostly fly international routes and from the carrier's major hubs.

United carried out unscheduled maintenance on seven of its Boeing 747 jets last month but found no safety-related issues.

The Federal Aviation Administration has been checking maintenance records at all domestic airlines after revelations surfaced about missed safety inspections at Southwest Airlines Co.