John Cox, 46, was initially locked up for four-and-a-half years after admitting committing arson during a Monarch flight from Birmingham to Sharm el-Sheikh in 2015.
But the Court of Appeal agreed with the Attorney General the sentence was unduly lenient and increased it to nine years and six months.
Drunk Cox forced the captain of the Egypt-bound airbus containing 194 passengers and seven crew to issue a 'mayday' call after lighting a fire in the toilets.
Drunken Cox, 46, caused chaos on the Egypt-bound airbus
Cabin crew found the blaze in a toilet in a waste paper basket and used two fire extinguishers and water to put it out.
The captain issued a "strongly worded" announcement warning passengers about the risk of smoking on board and the consequences of it.
He also debriefed the crew who were told to remain vigilant and it was decided to carry on with the flight, with four remaining fire extinguishers on board.
Just minutes later, when the plane was 100 nautical miles north west of Egypt at 35,000 feet, the captain received another warning about a fire.
This time it was discovered in the waste basket of a second toilet.
Drunken John Cox, 46, caused terror on the Egypt-bound airbus
Smoke and flames sounded and cabin crew struggled to put the blaze out, but were helped by an ex-pilot passenger who had also worked in the Derbyshire fire and rescue service.
By now two more extinguishers had been used as well as four and a half litres of water and the captain issued a mayday - making preparations to land at Alexandria and descending to 10,000 feet.
The captain, who had flown for Monarch for 20 years, said he had never experienced an incident with so much potential danger, Lady Justice Sharp said.
She said: "To throw a cigarette butt into a wastepaper bin without ensuring it is extinguished would show a high degree of recklessness.
Cox admitted committing arson during a Monarch flight from Birmingham to Sharm el-Sheikh
"On an aircraft at 33,000 ft, the conduct comes perilously close to deliberate fire-setting."
In January at Birmingham Crown Court, Cox admitted an offence of arson being reckless as to whether life was endangered.
Appeal judges heard the offence was out of character for Cox, who was a hard-working family man coping with his mother's death and his marriage breaking up.