WASHINGTON (7News) — Federal investigators uncovered new details on Wednesday in the deadly mid-air collision near Reagan National Airport that killed 67 people, including service members, in January.

Day one of the hearing at the National Transportation Safety Board (NTSB) headquarters in Southwest D.C. was emotional as families of the victims watched a newly released video and listened to audio from the moments leading up to the crash.

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Day two of the hearings continues Thursday morning.

According to the NTSB, the Black Hawk helicopter crew never heard a crucial order to pass behind an incoming American Airlines jet. Investigators say the military pilot had keyed her mic at the exact same time as the air traffic controller, effectively blocking the transmission.

“It’s heartbreaking, gut-wrenching, but also it brings me hope that we’re having these conversations,” said Aisha Duggins, sister of Kiah Duggins, one of the victims.

“That’s one of the primary reasons the collision happened they never should have even been in that path,” added Sheri Lilley, stepmother of American Airlines co-pilot Sam Lilley.

The hearing also revealed that the helicopter and jet were on separate radio frequencies, and that the Black Hawk crew was flying with conflicting altitude readings — one pilot believing they were at 300 feet, the other at 400. Investigators suspect faulty altitude instrumentation may have played a key role in the tragedy. Tempers flared during testimony, as NTSB board member J. Todd Inman pressed Army officials for answers.

“You’re telling me it’s going to be two months before you tell them there’s a discrepancy in their altitude? Could you hurry it up?” Inman said, referring to other military aircraft using similar systems.

“We are in public testimony, so we’ve put it out there I hope every Army aviator is not having to watch NTSB.gov to figure out there’s a discrepancy in their altitude,” said Erik Rosengren, a kennel supervisor with the U.S. Army, acknowledging the concern. The hearing continues through Friday, with more focus expected on Reagan National’s airspace design and whether safety systems failed both crews.

Lawmakers also weighed in. Senator Ted Cruz has called for all military aircraft to adopt ADS-B — a location-broadcasting system already used by commercial airlines — to avoid another tragedy.

The NTSB’s final report is not expected for another year, but these early findings are already raising serious concerns about military exemptions in civilian airspace and the urgent need for systemwide upgrades.