If you have ever closely observed a helicopter, you must have noticed the red and green lights. In fact, these lights are not only present on helicopters but also on commercial and private airplanes.

HOUSTON — We are getting a new look at the moment a helicopter crashed into a radio tower, killing four people near downtown Houston. The video does appear to answer the question everyone has been ...

HOUSTON -- The aviation obstruction lights at the top of a radio tower hit by a helicopter in a deadly crash in Houston, Texas, have a history of not working, according to a report. SkyEye reporter ...

HOUSTON, Texas (KTRK) -- Eyewitness News learned the aviation obstruction lights at the top of a radio tower hit by a helicopter in a deadly crash in Houston's Second Ward have a history of not ...