Niki Lauda and James Hunt were close friends off the track but fierce competitors on it © Sutton Images Enlarge

Testing for a Formula One driver is a bit like the revision before an exam or the preparation before a Powerpoint presentation - boring but crucial for success. For James Hunt, however, testing could also be the morning after the night before.

Midway through the 1977 season Hunt and his team McLaren were struggling to defend their championship, having retired from a number of the earlier rounds. The team were keen to develop the car and a series of tests between races were scheduled. Hunt, it is fair to say, wasn't so enthusiastic.

For one test he had arranged to fly to the Paul Ricard circuit from Salzburg with his good friend and pilot Niki Lauda. The pair had been out the night before but Lauda hadn't been able to keep up with Hunt and, mindful of the test the next day, went home early. "We'd had a hell of a night," Lauda recalled. "We drank and smoked far too much, but he outlasted me and I went to bed far earlier than him."

As the morning fog cleared from the airport runway Lauda sat waiting in the plane for Hunt's arrival. Just as he was making his final pre-flight checks a taxi tore onto the runway and Hunt bundled out of the back with a large portable stereo in hand. He was followed by a beautiful but exhausted looking Austrian lady who was wearing a white dress complete with conspicuous grass stains. The champion said goodbye to his sweetheart, staggered to the aircraft and instantly fell asleep in the back. He slept the whole way to the circuit.

James Hunt on the limit of adhesion in his 1977 McLaren © Sutton Images Enlarge

At the track Lauda's Ferrari, which had been very successful in the opening rounds, developed a fault and he had to be content with watching Hunt from the pit wall. Several laps into the session and an alarm rang signalling a car off the circuit. Lauda feared the worst: "Shit! James is still pissed and he must have crashed."

He and McLaren boss Teddy Mayer jumped into the ambulance and the paramedics sped to the scene of the accident. As they pulled up to the stationary McLaren, Lauda noticed there was no significant damage to the car - it hadn't been too serious.

He and Mayer peered into the cockpit to see Hunt slumped back in his race seat. Mayer read the situation immediately and ordered his driver to go back to the hotel and sleep it off. The penny then dropped for Lauda: "James - the silly arsehole - he parked the car and fell asleep!"

Quotes used with permission from "James Hunt - The Biography" by Gerald Donaldson published by Random House