In this Jan. 12, 2015 file photo, a woman is transported in a wheelchair onto an ambulance as people are evacuated from a smoke filled Metro subway tunnel in Washington. (Jacquelyn Martin/AP)

THE PATCHY information known so far about the underground calamity in a smoke-filled Metro tunnel that left one passenger dead and dozens injured last week can only leave the transit system’s customers shaking their heads. An emergency radio dead zone; reports of difficult-to-open subway car doors; botched communications and possibly malfunctioning fans — none of it inspires confidence in the safety culture of an agency that claimed to have made strides in that direction.

Nor does it help that Metro officials have been all but mum since the Jan. 12 incident near L’Enfant Plaza, caused by an electrical meltdown linked to the cables that supply power to the third rail on the Yellow Line. Metro’s near-silence stands in contrast with the District, where Mayor Muriel Bowser’s office proved itself relatively quick, and accountable, by releasing a preliminary report Saturday.

With information forthcoming from the city, whose firefighters handled the rescue, but not from Metro, the story so far is necessarily one-sided and quite possibly tilted.

True, say the District’s emergency responders, it took a half-hour before rescuers reached the first car of the stricken, six-car train to begin evacuating choking passengers that Monday afternoon. But, they add, that was because Metro’s initial emergency call mentioned only smoke but no stuck train (meaning the fire department’s initial response was less than full-throttled); because their radios wouldn’t function underground (despite warnings conveyed to the transit agency by the fire department about the failure of the tunnel’s signal-boosting equipment, maintained by Metro); and because of the firefighters’ uncertainty that power had been shut off to the third rail.

Perhaps Metro’s account, once it is revealed by the National Transportation Safety Board, will give a fuller picture. Yet according to Metro’s own records, as reported by The Post, the rail system was beset by 171 smoke and fire incidents in the 20 months that ended Sept. 1, an average of roughly two incidents per week. That seems alarmingly high.

The public deserves to know whether the underground fans that are supposed to be able to keep subway tunnels ventilated were unable to clear the smoke that engulfed the train. It deserves to know why firefighters arrived on the subway platform still unaware that a train was stranded 800 feet down the track.

It deserves to know whether the cables that supply power to the third rail are properly maintained; why the train, once stopped, could not reverse direction to the L’Enfant Plaza station to enable a speedy evacuation; and why rescue workers were apparently initially unable to open doors to the first train cars they reached.

At the least, the delay in reaching the first trapped passengers suggests an array of technical, communications and logistical lapses of the sort that Metro pledged to resolve after the June 2009 Red Line collision that left eight passengers and a train operator dead. After so much money spent on safety and so many assurances delivered, answers are urgently needed from Metro.