UPDATE 2-Shareholder of Air Canada parent to oppose windup

(Adds shareholding in class B stock in paragraph 2)

CALGARY, Alberta, Jan 14 (Reuters) - One of the largest shareholders of Air Canada's (ACa.TO) parent, ACE Aviation Holdings Inc (ACEa.TO), said on Wednesday it will oppose ACE's planned windup, saying it is not in the best interest of investors.

West Face Capital Inc, which according to Reuters data owns 13.86 percent of the holding company's class A stock and 5.58 percent of the class B stock, said it does not want ACE to distribute its 75 percent interest in Canada's dominant airline and other assets to investors.

"We just don't think that the liquidation is the best course of action and we'll have more information in short order," West Face spokesman Gregory Boland said.

He did not elaborate.

ACE shareholders are due to vote on the windup plan on Feb. 27.

For more than a year, ACE Chief Executive Robert Milton pored over several potential ways to end Air Canada's holding company structure, including launching a secondary offering of shares or buying back the minority shareholding.

But his efforts were complicated by the downturn in the airline industry and Air Canada's falling share price.

In early December, ACE announced the windup plan, which includes buying back preferred shares and convertible notes before liquidating the assets.

Before ACE announced its plans, West Face issued a press release saying it aimed to oust the holding company's directors. It said it had become concerned about ACE's intentions for the company's cash.

Shares in ACE fell 15 Canadian cents, or 2 percent, to C$8.20 on the Toronto Stock Exchange on Wednesday. That is more than double their value before the company announced the liquidation plan.

($1=$1.25 Canadian) (Reporting by Jeffrey Jones; editing by Peter Galloway and Gunna Dickson)