By Praveen Menon WELLINGTON (Reuters) -New Zealand's main opposition National Party selected on Tuesday a former chief executive of the national carrier as its new leader to face Labour Prime Minister Jacinda Ardern in the next election expected in 2023. Christopher Luxon, who helmed Air New Zealand for seven years until September 2019, was elevated to the top job just a year after entering parliament following a leadership crisis at the National Party that has seen four leaders replaced in as many years. He comes in after Judith Collins, who headed the National's campaign in its worst election defeat in 2020, was dumped last week. "Today we are drawing a line under the events of the last four years, and we are putting them behind us," Luxon said in his speech after he was appointed leader.