"Helicopter in DC plane crash was flying twice as high as it should have, lacked new altitude tech "

https://www.aol.com/helicopter-dc-plane-crash-flying-223530282.html 

"The collision may have been avoided if the Army had outfitted the Black Hawk with Automatic Dependent Surveillance-Broadcast ADSB, a that allows air traffic control to see an aircraft's ALTITUDE, Sen. Ted Cruz (R-Texas) said on Friday.."

https://www.aol.com/helicopter-dc-plane-crash-flying-223530282.html