WASHINGTON (AP) _ Consumer groups are attacking a government plan to exclude mechanical problems from the delays included in airlines' on-time performance ratings.

The Transportation Department issues periodic ratings of the airlines' performance. It began including delays caused by mechanical problems on Jan. 1.

But airline pilots and mechanics told the department they were afraid the change might result in pressure to start flights before they felt all safety concerns had been met in order not to be late or to avoid a cancellation.

The consumer coalition discounted that concern Wednesday, however.

Former National Transportation Safety Board Chairman Carl Vogt said he has confidence in the integrity of the people who make flight safety decisions, the crews, mechanics and executives.

And David Stempler of the International Airline Passenger Association said consumers should have access to statistics on all flight disruptions, regardless of cause.

The coalition issued a consensus statement calling on the government to delay making the change while it seeks further comment and urged that delays caused by mechanical problems continue to be counted in published statistics.

Others joining in the statement were Sara Cooper, National Consumers League; Darryl Jenkins, Aviation Foundation; Ed Perkins, Consumer Reports Travel Letter; Hugh Tietjen, J.D. Power and Associates; Geraldine Frankoski, Aviation Consumer Action Project; and Tom Parsons, Best Fares Magazine.