DuPont, Washington (CNN) Two of the three passengers who died when an Amtrak train derailed while traveling along a route for the first time were enthusiastic advocates for travel by trains, the Rail Passengers Association said Tuesday.

The Washington, D.C. -based organization identified the men as Jim Hamre and Zack Willhoite.

Amtrak Cascades 501, carrying 86 people on its initial journey with paying customers, was on a new section of the route from Seattle to Portland when it derailed Monday. The National Transportation Safety Board, which said a cause of the accident will be determined later, said the train was going 50 mph over the limit when it went around a curve.

The two men killed were friends who traveled to ride trains together, CNN affiliate KIRO reported.

"Jim was among the country's most respected and effective rail advocates and a good friend and mentor to me. I will miss his counsel, and our community is poorer for his loss," Rail Passengers Association President Jim Mathews said in a statement. "Both Jim and Zack have been advocates of transit and passenger rail for decades, and we can't thank them enough for their work. Our thoughts are with their families at this time."

Hamre and Willhoite also were members of All Aboard Washington, a rail advocacy group in their home state.

The high-speed catastrophe killed three people and hurt more than 100.

The train derailed after careening around a curve at almost three times the speed limit, hurling passenger cars off an overpass onto rush hour traffic below.

"It was like being inside an exploding bomb," passenger Charlie Heebner told CNN affiliate KOMO.

It's not clear why the train was traveling at 80 mph in a 30-mph zone, said National Transportation Safety Board member Bella Dinh-Zarr.

But this much we do know: The track had undergone millions of dollars of improvements and weeks of testing.

Yet positive train control -- technology that automatically slows down and stops a speeding train -- wasn't activated, much to the dismay of the NTSB official.

"We have recommended PTC for decades," Dinh-Zarr said Tuesday. "Unfortunately the deadline was moved farther into the future, and every year that we wait to implement PTC to its fullest extent means that more people will be killed and injured."

Incoming Amtrak CEO Richard Anderson later told reporters that it wasn't immediately apparent whether PTC would have kept the train on the tracks.

"It's not clear yet from the NTSB whether PTC would have prevented the accident or not," Anderson said. "We really must wait for the NTSB to give us that information."

Latest developments

-- There were two people in the cab in the front locomotive during the crash, Dinh-Zarr told reporters Tuesday afternoon. The engineer was joined by a conductor who was learning the new route, she said. Amtrak's Anderson said that is not unusual.

-- The engineer had been on this stretch of track before, NTSB lead accident investigator Ted Turpin said. "Within the previous two weeks he had been qualified to operate on the territory," Turpin said, while adding investigators don't yet know how many hours of previous travel that involved.

-- Investigators were able to learn the train's speed from a data recorder retrieved from the rear locomotive. The recorder from the front locomotive was recovered Tuesday, Dinh-Zarr said. Cameras from the train were damaged and have been sent to Washington to see whether video can be retrieved.

-- Dinh-Zarr also said that section of the route had a system that cannot enforce speed restrictions on a train, as PTC can. "Sound Transit had centralized traffic control, which is CTC," she said. Sound Transit spokesman Geoff Patrick said earlier that PTC was installed in the segment of tracks where the derailment happened, but wasn't operational yet.

Mayor: This tragedy could have been avoided

Lakewood Mayor Don Anderson had long worried the rail line, which passes through his city, would one day prove dangerous. He's thought so since 2013.

He told CNN on Monday night that his immediate concern was for victims and their families in a tragedy "that could've been avoided if better choices had been made."

"Our community was concerned about the safety of a high-speed passenger rail line coming through an urbanized area on what had been, for years, essentially an abandoned rail route," Anderson said after the derailment.

Lakewood sued Washington's Department of Transportation in 2013, saying, in part, that the passenger rail project had not "undergone sufficient environmental review," according to court documents. The city's suit was dismissed in 2014, court documents show.

At a town meeting earlier this month, Anderson said it was only a matter of time before the high-speed trains killed someone and asked for more safety improvements.

"Come back when there is that accident, and try to justify not putting in those safety enhancements, or you can go back now and advocate for the money to do it, because this project was never needed and endangers our citizens," he said, according to CNN affiliate KOMO.

Tuesday a spokeswoman for Lakewood, Brynn Grimley, released a statement from the city that said the mayor was voicing his concern at that town meeting about seven railroad crossings within the town limits and not the accident site.

"His comments focused on the city's concern that there are not enough safety precautions in place to protect pedestrian and vehicle traffic around the railroad crossings in Lakewood," the city's statement says. "This in no way was intended to predict what happened in DuPont, nor was the mayor speaking about the possibility of a train derailment outside city limits."

The train derailed around 7:40 a.m. in DuPont, about 20 miles south of Tacoma, Washington.

The train apparently came out of a curve and ran off the track while crossing or approaching an Interstate 5 overpass.

Lakewood is about 10 miles from DuPont.

The state Department of Transportation did not immediately respond to CNN's request for comment on Anderson's statements.

How did this happen?

The NTSB and local authorities have not said what caused the crash. Investigators will likely examine the track, human performance, operations and the mechanics of the train.

Cars from an Amtrak train that derailed above lie spilled onto Interstate 5.

Most of the route was graded for a maximum speed of 79 mph, but the speed limit on the curve where the crash occurred is 30 mph, said Rachelle Cunningham of Sound Transit.

Witnesses said they saw the train speeding.

Daniel Konzelman, who was driving on Interstate 5 at the time, said the train and his car were "kind of parallel" and "it was going faster than us."

Aerial view of the jumbled rail cars in Washington State.

Amtrak has equipped 49% of its locomotives and 67% of its tracks with PTC, according to Federal Railroad Administration data from the second quarter of 2017.

The biggest obstacle to PTC is cost. Anderson said Tuesday that Amtrak employees are "huge supporters of positive train control. We have all of our capital allocated to get it done."

In response to a 2008 head-on collision that killed 25 people near Los Angeles, Congress passed a law ordering railroads to adopt PTC by December 2015. But the railroad industry has opposed PTC because of its high cost and technological issues.

As 2015 came to a close, several railroad companies threatened to shut down services unless Congress gave them more time, maintaining the deadline wasn't realistic given the complex technology.

So Congress extended the deadline, giving companies until December 31, 2018, with extensions up to 2020 if certain requirements are met.

The Association of American Railroads estimated that as of March 2017, freight railroads had spent $8 billion and passenger railroads $3.5 billion to meet the PTC mandate.

"The reason why they've been given so many extensions has been money," said Mary Schiavo, a CNN analyst and a former Department of Transportation inspector general. "It is expensive to put it on tracks all over the country."

A first day gone awry

The train was running on track previously used for occasional freight and military transport, the Washington Department of Transportation said. The track had undergone millions of dollars of federally funded improvements and weeks of inspection and testing, the agency said.

Previously, the tracks where the derailment occurred were owned by BNSF. The tracks are now owned by Sound Transit, which managed the track upgrade in preparation for commuter service, the state department of transportation said.

Heebner, who compared the crash to an explosion, said he and his wife, Beverly, had been looking forward to the route's inaugural run.

"We knew about this thing. I'd been waiting for it. And we said this is the first run, we're going to ride that first run," Heebner told KOMO.

But their adventure was soon marred by carnage.

"There was this body lying there," Beverly Heebner said. "I mean he hardly had any clothes on, the clothes had just been ripped off of him. And he was obviously dead."