A shocking new discovery pulls back the curtain on what may have happened in the moments leading up to the Air India plane crash last month — with a report finding the fuel to the doomed plane’s engines was likely cut just after taking flight.

A black-box recording of dialogue between the London-bound Boeing 787’s two pilots suggests the captain — Sumeet Sabharwal, who was reportedly known as “Sad Sack” in flight school because he always looked sorrowful — flipped fuel switches off, according to a Wall Street Journal report about the official probe into the catastrophe.

The Wall Street Journal reports the voice recording indicates the co-pilot, Clive Kunder, asking … “Why did you cut it off?” which Sabharwal denies doing on the recording.

The WSJ’s report follows details released by India’s Aircraft Accident Investigation Bureau (AAIB) confirming the fuel switches had been turned off.

The AAIB report allegedly says each switch was turned off one second apart but flipped back on to “RUN” about 10 seconds later. Engine control systems are programmed to jump into a recovery sequence when the switches are moved from “CUTOFF” to “RUN.”

However, it was too late for 241 out of 242 passengers and crew members aboard.

We reported the news — the Dreamliner took off normally on June 12, but quickly began sinking before plowing into the B.J. Medical College hostel in Ahmedabad, India. 260 souls lost their lives during the crash, with just one man miraculously walking away with minimal injuries.

It’s unclear why Sabharwal would purposefully cut fuel to the engine.

A friend and neighbors tell The Sunday Times he was planning on ending his flight career to care after his father and even called his dad before takeoff, saying … “I’ll call you once I reach London.”