Khalid Mir, 39,  swore and threw drink over passengers and crew on the flight in November. He was restrained after ignoring the pilot's warnings.
He spat in the face of a steward who came to give him a drink.
Mir, of Havelock Road, Saltley, Birmingham, admitted being drunk on an aircraft and failing to obey the pilot.
Prosecutor Colin Phillips said Mir became involved in an "altercation" with a female passenger on the seven-hour flight, which "became an issue which required the flight crew's attention".
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He was given a warning about his behaviour by pilot Alan McIntosh.
"However, the defendant's behaviour was still threatening and disorderly and it was eventually felt necessary to restrain him at the back of the aircraft.
"He was tied into a seat with his hands and feet tied and it was decided to place a mask over his mouth for other people's protection," said Mr Phillips.
He spat at a female steward who tried to give him a drink through a straw and called her a "dirty white".
In a statement read to the court, she said: "When it was my turn to check on him, I gave him drinks through a straw.
"He spat in my face when I was only three feet away. I was disgusted."
Mir was arrested when the flight landed.
Magistrates were told he had more than 50 previous convictions, including for drug-related offences.
Mir will be sentenced at Birmingham Crown Court on 8 March.
A drunk plane passenger had to be tied to a seat with a mask over his mouth during a flight from Dubai to Birmingham, magistrates heard.