Officials are still struggling to piece together what happened to Amtrak Northeast Regional Train 188 when it derailed Tuesday night near Philadelphia. But the incident has already raised questions about the overall safety of America's aging railroads. With Congress weighing deep cuts in Amtrak's budget, the crash is drawing renewed attention to ways that rail operators could more cheaply and reliably keep everyone safe.

Soon, that may include the use of unmanned drones.

Last week, Texas-based BNSF Railway became the first to receive permission from the Federal Aviation Administration to use drones to inspect some of the 32,500 miles of track in its network. The freight railroad currently sends humans out to do its safety inspections. But, the company says, it can be a dangerous and difficult job, with employees sometimes clambering over slippery objects to reach their sites or working in risky high-traffic areas.

BNSF argues that using drones could be safer for track workers and in some cases more effective than using fixed-wing aircraft, which can't fly as close to the bridges and tunnels that may need inspection.

With the FAA as a partner, BNSF is gearing up to use drones in what are called beyond-line-of-sight operations — in which a ground-based operator is allowed to fly the unmanned vehicle without keeping the device in their visual range. The FAA's current proposed rules for drones requires operators to be able to see the drone at all times. But this new research is expected to help loosen the FAA's drone rules someday.

BNSF, which operates mostly in the western United States, says it plans to use three types of drones for the tests, the AirRobot AR180 and AR200 as well as the 3DRobotics Spektre Industrial Multi-Rotor Aerial vehicle.

"BNSF is constantly exploring additional ways in which it can improve safety for its employees, its customers, and the public," the company wrote in its initial petition to the FAA. "BNSF anticipates that use of [drones] will enhance safety in railroad operations."

Along with BNSF, two other companies — CNN and drone manufacturer PrecisionHawk — are collaborating with the FAA to study how to expand drone usage in the United States.

"We anticipate receiving valuable data from each of these trials that could result in FAA-approved operations in the next few years," the FAA said last week in a statement. "They will also give insight into how unmanned aircraft can be used to transform the way certain industries do business – whether that means making sure trains run on time, checking on the health of crops, or reporting on a natural disaster."

It's not hard to imagine Amtrak someday using drones to monitor its own network of rail lines. In principle, the quasi-public rail company could ask for permission from the FAA to do just what BNSF is doing now. And thanks to BNSF's precedent, Amtrak's request for an exemption from the FAA's drone ban could be expedited by the agency, according to Lisa Ellman, an industry lawyer who has worked closely with groups that want to expand drone usage. From start to finish, the process might take as little as a few weeks.

Given Amtrak's chronic organizational and budgetary problems, it could be years before it makes the leap. (An Amtrak spokesperson didn't immediately respond to a request for comment.) It's also hard to say whether closer inspections would have made a difference in the case of Northeast Regional 188. But faulty track conditions have been blamed for derailments in the past — and in the future, drones may help catch the worst of these before they result in a disaster.