The Black Hawk helicopter involved in Wednesday night’s deadly plane crash outside Washington, D.C., was built at Sikorsky in Stratford. The company said it is “deeply saddened” and is assisting with the investigation.

Here’s what to know about the aircraft dubbed “the workhorse of the Army.”

The UH-60 Black Hawk has been deployed to dozens of combat zones around the world. Sikorsky has built more than 5,000 of them in Stratford since the 1970s.

Now, the company is helping investigators figure out what went wrong in the chopper’s deadliest crash on American soil.

“We are deeply saddened and send our condolences to those that lost loved ones,” Sikorsky said in a statement. “We have offered our support to the investigation and our customer. Safety is our top priority.”

Over the past five decades, the UH-60 and its military variants have been involved in more than 400 incidents that led to just over 1,000 deaths, according to Aviation Safety Network records.

The National Transportation Safety Board said that the Black Hawks had a flight data recorder similar to “black boxes” found on passenger jets. But neither aircrafts’ recorders had been recovered as of Thursday afternoon, investigators said.

Experts said Sikorsky will likely send a representative to assist with technical questions about the aircraft. But they cautioned that concrete answers could be months or even years away.

“It can be dangerous to have a knee-jerk reaction to what exactly happened,” said Jonathan Hemler, a military aviation analyst with Newtown-based Forecast International.

Hemler flew choppers similar to the UH-60 Black Hawk as a Navy pilot.

He said that although some military choppers have anti-collision systems, they are fairly simplistic.

“Certainly, they’re less complex and less advanced than commercial aircraft, which would have been on board this American Airlines flight,” said Hemler. “There’s so much traffic in that area that, you know, a collision avoidance system in some cases could be overwhelming. And frankly, not helpful." Civilian passenger jets do come with the Traffic Collision Avoidance System. But TCAS shuts off below 1,000 feet, where pilots rely on their own visuals and air traffic controllers.

As for the Black Hawk, a crew chief is typically the eyes and ears outside.

“Always a mission for the cabin crew chief is to be looking for other aircraft,” Hemler said.

The crew that was flying the Army Blackhawk helicopter was “very experienced” and were not new to the unit or the congested flying that occurs daily around the nation’s capital, said Jonathan Koziol, chief of staff for Army aviation.

President Donald Trump suggested in a news conference that the Army pilots and air traffic controllers made mistakes. The president asserted his opinion even though the crash has yet to be fully investigated and there has been no determination as to whether the FAA or the pilots did anything wrong.

“The people in the helicopter should have seen where they were going,” Trump said. “What was the helicopter doing in that track? Very sad. But visually, somebody should have been able to see and taken that helicopter out of play and they should have been at a different height.”

Defense Secretary Pete Hegseth also appeared to blame the military flight crew.

“Tragically last night, a mistake was made. I think the president is right,” Hegseth said. "There was some sort of an elevation issue that we have immediately begun investigating at the DOD and Army level.”

Hours later, NTSB Board Chair Jennifer Homendy pushed back saying, “We look at facts on our investigation and that will take some time.”

Over the next few decades, the Pentagon plans to gradually phase out the UH-60 Black Hawk. In 2023, the Army picked a chief competitor to replace the current chopper.

Sikorsky’s “DEFIANT X” lost out to rival Bell Textron’s V-280 Valor, a futuristic tilt-rotor aircraft that’s a major departure from the Black Hawk. The Army’s rejection led the Connecticut congressional delegation to raise safety questions about the Valor.

Sikorsky is one of the state’s largest employers, with close to 8,000 workers and 242 subcontractors. But the impact won’t be immediate. Sikorsky’s current Black Hawk contract runs for three more years, and it may be extended through 2033. The company also said Black Hawk sales to foreign countries are rising.