The pilot of a United Airlines plane that he says was targeted by terrorists on 9/11 is opening up about how frustrated he’s been with the government’s deafening silence.

Tom Mannello joined us on “TMZ Live” Friday — the 25th anniversary of 9/11 — to discuss what went suspiciously sideways on his flight … and how he tried to put the events of the day out of his mind.

We told you all about United Flight 23 in our documentary “TMZ Investigates 9/11: The Fifth Plane” … the plane was scheduled to take off from JFK at 9:00 AM for LAX … but it never got off the ground. A total of 7 people on board raised suspicion.

With evidence that people were hiding in the plane’s hatch, the FBI secretly interviewed the whole crew … even showing them a lineup.

Tom says he feels helpless and frustrated by the lack of information about what really went down … with no resolution a quarter-century later.

The only information he says he has obtained since that fateful day has been from a couple news stations.

He says United is also faced with the same situation … the government just hasn’t spoken about this — ever.