Mercedes motorsport boss Toto Wolff believes Formula 1's current 2016 calendar will put a strain on the German team, forcing it to eventually change its structure to cope with the extended workload.
Next year's schedule includes two additional races from this season's 19-race programme, although the US Grand Prix at Austin has been granted provisional status pending a solution to its financial affairs.
Speaking at this weekend's Mercedes Stars and Cars event in Stuttgart, Wolff voiced his concerns on the matter.
"It's definitely a lot for the travelling team," said the Mercedes boss. "Nineteen races already was a lot this year and next year back-to-back races are quite difficult."
Six back-to -back weekends are effectively registered on the 2016 calendar, with Baku in Eastern Europe following Montreal in North America as the most impressive flight path the teams will be forced to endure over the course of a few days.
"We need to have a look at the organisation - everyone is getting pretty tired at the end of the season - and I am not sure we can actually cope with 21 races in the current structure," Wolff concluded.
"We have to be looking at maybe having second shifts, rest times after the race weekends. It's quite a complex thing to do for next year."
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