NTSB releases more details on fatal mid-air crash

BOULDER - The question at the center of an investigation into a weekend mid-air plane crash over Boulder County, which killed three: How is it possible that on a clear day two experienced pilots never saw each other until it was too late?

National Transportation Safety Board investigators have interviewed the pilot of a glider which was able to fly right through the remnants of the collision. Investigators say his words will prove to be vital in the ongoing investigation.

The glider was being towed at the time by one of the planes involved in the crash.

Brothers Bob and Mark Matthews, who were in a Cirrus, and Alexander Gilmer, the pilot of that tow plane, were all killed in the crash.

On Monday, the NTSB said the pilot of the glider saw an approaching plane just to his right and had just a few seconds to realize what happening before he decided to break off from his tow plane.

The resulting collision was viewed by a lot of people on the ground.

On Monday, the city of Boulder released a series of calls that came into 911 on Saturday afternoon.

"It looks like a plane is on fire and we can see a parachute," one caller said.

Multiple witnesses who called 911 after seeing the crash, mentioned a parachute being deployed. The divice is also visible in multiple photos of the collision.

Federal investigators say it's unlikely they'll be able to tell us if anyone tried to escape.

"It's probably going to be impossible to quantify or establish factually that an individual jumped from any of those airplanes," Jennifer Rodi, a spokeswoman for the NTSB, said. "The Cirrus was on fire. One individual was found within the wreckage of the Cirrus and two individuals were found outside of wreckage."

The NTSB says some who saw the crash, have their theories.

"According to the witness statements, it's a 90-degree angle at impact," Rodi said. "However we have not confirmed that through wreckage examination or further analysis of the radar data."

Also released on Monday was the fact that the tow plane was slowly ascending, the other plane was slowly descending. That plane had a low wing and it conceivably could have caused what in essence is a blind spot. Former NTSB Investigator Greg Feith says don't overlook that.

"What the investigators are going to try and do is understand what the altitudes were or positions - relative positions - to each other, to see if, in fact, there was a blind spot that prevented one or both pilots from seeing each other until the very end, or right at the time of the collision," Feith, 9NEWS aviation analyst, said.

The wreckage of the two planes is currently at a hanger in Greeley where it's being reassembled.

"With the 3-D reconstruction, we just try to lay out the wreckage to resemble what the airplane would look like as a normal airplane getting ready to go out and fly," Rodi said. "So, we orient the wings, the fuselage, the empennage, in their correct anatomical position."

It could take upwards of a half year to an entire year for the NTSB to issue its final report on the crash.