The airline's top executive has told employees to avoid drawing premature conclusions about the June 12 accident

The preliminary investigative report into the recent crash of an Air India Boeing 787-8 Dreamliner did not reveal "mechanical or maintenance issues" with the aircraft, the airline's CEO Campbell Wilson told employees in a letter that was seen by The Print website and other Indian media outlets on Monday.

Wilson also discouraged employees from relying on speculation and rumors that had been circulating in the media following the release of the initial report by India's Aircraft Accident Investigation Bureau (AAIB).

"Instead of focusing on interpretations, I suggest we note that the Preliminary Report found no mechanical or maintenance issues with the aircraft or engines, and that all mandatory maintenance tasks had been completed," Campbell said in the letter.

"There was no issue with the quality of fuel and no abnormality with the take-off roll. The pilots had passed their mandatory pre-flight breathalyzer and there were no observations pertaining to their medical status," Campbell added, urging "everyone to avoid drawing premature conclusions as the investigation is far from over." 

As a precautionary measure, Wilson wrote, all Boeing 787 aircraft in Air India's fleet underwent checks within days of the accident and were deemed fit for service. 

The UK-bound plane carrying 242 people crashed into a residential area in Ahmedabad, India shortly after takeoff on June 12. Only one person on board survived. Nineteen people on the ground were also killed. 

The AAIB report, released on Saturday, revealed that cockpit switches controlling the fuel supply were moved to the 'cut off' position seconds after takeoff, shutting off fuel to both engines. 

On Monday, India's aviation regulator, the Directorate General of Civil Aviation, directed all domestic carriers operating Boeing 787 and 737 aircraft to complete crucial inspections on their fuel switch locking systems by July 21.