Lewis Hamilton is entering the new Formula One season with the mind-set of a challenger rather than a defending world champion. “I don't want to sit here and say I'm world champion, I sit here saying I want to be world champion,” Hamilton said Friday at the launch of the new McLaren car for the 2009 season. “Going into my third year, I have had to reset my targets right back to where I started in 2007. We want to win world championships for both titles (drivers and constructors) for the team as well.” At 23, Hamilton became the youngest driver to win the F1 championship, and he's hoping another year's worth of experience will help him defend the title. “We have to improve on the mistakes we made last year and hopefully we can push on,” he said. “We want to win, that's what we're here for.” Like all the other F1 drivers, Hamilton, who won the 2008 title on the final lap of the final race last season, will have to master a major series of rule changes involving aerodynamics, slick tires, a new power boosting system and adjustable front wings designed to lead to more overtaking. Like other F1 cars, the McLaren MP4-24 has major changes to the front and rear wings and the drivers will have even more work to do in the cockpit, switching on the power boosters up to twice a lap and adjusting flaps on the front wings. “I haven't driven the car yet so I can say what they're like,” said Hamilton, who will again have Finnish driver Heikki Kovalainen as his teammate. “This is the first time I have seen it put together. It looks beautiful to me. The team always puts together a sound car and it's great to see the final outcome of all the hard work that's gone on.” As well as defending the F1 title, Hamilton is looking forward to meeting Queen Elizabeth II where he will collect the MBE (Member of the Order of the British Empire). “That came as quite a surprise,” he said. “It's a proud moment for myself and my family. “After only two years in F1, to be given such an award I am very honored and I can't wait to go to the Palace.” Ron Dennis announced at the same news conference that he was stepping down as team principal on March 1, a month before the new season starts in Melbourne, Australia. He will hand over to Martin Whitmarsh, the team's chief operating officer, who will have the task of guiding McLaren to its first constructors' title since 1998. “Our objective this season is to win both championships,” said Dennis whose team lost last season's constructors titles to Ferrari by 21 points even though Hamilton won the drivers' title. “But the first target is to win the first Grand Prix (at Melbourne March 29) and the reason of the season will follow on. It's up to how we use the team between now and Melbourne.”