Family members of the victims from Wednesday's plane crash in Pueblo County tour the site Saturday.
The small plane crashed, killing all 8 people on board.
According to the N.T.S.B., a control tower operator warned the pilot to pull up before the plane crashed.
Chief investigator Frank Hilldrup says the tower is outfitted with a device called a "Minimum Safe Altitude Warning", or M-SAW, which alerts operators when a plane is flying too close to the ground.
"We believe they got a warning in the control tower because the controller mentioned something at the very near the end... we think of the flight... about basically check your altitude."
The N.T.S.B. says the plane was flying at an altitude of about 300 feet 4 miles away from the runway. According to aviation experts, the plane should have been at three times that altitude.