AKRON, Ohio-- A little more than one year after the crash of a private jet into an Akron apartment building killed nine people, the NTSB is prepared to release its findings and conclusions.
The investigation has filled thousands of pages examining everything from the pilot history to the weight of the aircraft to the maintenance of the aircraft and weather.
The chartered Hawker 125, operated by Executflight of Fort Lauderdale, Florida, crashed on approach to the Akron Fulton Airport on November 10, 2015, with seven employees of Florida-based Pebb Enterprises and two pilots on board.
The NTSB released a detailed report about the crash in April without drawing any conclusions about the cause of the crash.
Since then investigators have continued gathering information including a September deposition of former Execuflight pilot Donnie Ray Shackleford, who was fired from the company after he had already been subpoenaed to give the deposition.
In his statement to investigators, Shackleford makes alarming claims.
At one point in his interview he was asked, "a few moments ago you were asked if you were ever asked to lie about any of the information provided to the NTSB. Were you ever asked to lie about the information we just gone over here (in this deposition)?"
Shackleford answered, "Yes. There was a time that I felt like yes, that they were misleading the investigation," Shackleford told the NTSB.
He cited providing false weight and balance information as an example.
"And just they made such a scramble to change records and eliminate stuff right after that accident, it would make your head spin," he added.
Shackleford says one of the two pilots, Renato Marchese, had earlier expressed to him a concern about working with the other pilot of the plane, Oscar Chavez, explaining that between them they did not have enough experience on the plane, particularly when flying in bad weather.
"He just didn't feel like, the way he talked to me was, I'll use the exact terminology, words he used to me one time, and he said and this was prior to when I got sick (as his copilot on a previous flight), he said, "if they put me and Oscar together, we're going to get ourselves killed," said Shackleford.
Shackleford expressed concerns about pilot flying time and aircraft maintenance.
But in a separate deposition the CEO of Execuflight denied the accusations.
An October letter from Execuflight to the NTSB concludes that at the time of the accident the company had in place a robust safety culture trying to prevent just such a crash.
In the letter, the company suggests that air traffic controllers contributed to the crash.
Daniel Lewkowicz said pilots had an option to refuse a flight if they had any concerns.
He rebutted any suggestion that the company had intentionally manipulated flight records including weight and balance records.
During a previous deposition, Lewkowicz was asked: "What is your philosophy about safety at Execuflight?" to which he responded: "No negotiations on anything that would, at any one way or another be a safety compromise."
The NTSB has given no indication of how much weight investigators will be giving to Shackleford's comments when they release their findings on Tuesday.
The plane's manufacturer has also written a letter to the NTSB suggesting that pilot error was to blame for the crash.
Several families have already filed lawsuits on behalf of the victims.