Lewis Hamilton worried engine penalties could harm F1 title defence
Lewis Hamilton fears engine-related grid penalties will harm his attempts to win the world title this year.
A maximum of five changes are permitted to the six parts of an engine before a grid penalty is incurred.
The Mercedes driver has made a fifth change to two parts for this weekend's Austrian Grand Prix.
"We are putting in the last new engine this weekend and so at least one race I will start last and will need a sixth and even a seventh engine," he said.
Hamilton said he felt that the problems were singling him out, and that the other seven drivers using Mercedes engines were not suffering the same issues.
"I'm the only Mercedes driver to have that," Hamilton said. "And we are the Mercedes team. If there are 40 engines then you'd hope that we would have the best ones.
"Everyone else is on their normal plan and have four engines left. There's nothing I can do about it, it is what it is. I hope Mercedes learn from it and from the faults on mine."
As a comparison, drivers' championship leader Nico Rosberg is on his second of all the six elements of the engine, while Hamilton is on now on his fifth turbo and MGU-H (the part of the hybrid system that recovers energy from the turbo), his fourth energy story and control electronics and his third engine and MGU-K (energy recovery from the rear axle).
Some of the engine parts Hamilton has already used can be run again in practice sessions to limit the mileage on his race engines.
After the last race in Azerbaijan, which Rosberg won to open up a 24-point lead over the defending champion, Hamilton said he felt this was "looking like a good year for Nico".
But Rosberg countered in Austria by saying: "What he says, with all due respect, doesn't change my way of thinking and how I approach it.
"The fact is he's always beaten me in the last two years so it's always going to be tough against him and I can guarantee you he hasn't given up, far from it.
"The best way for me to win is Austria is just to focus on the task at hand and make sure I get this one right."
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