However, Mr Hayes insisted that it made sense to keep the bulk of UTC — which makes Otis elevators, Pratt & Whitney aircraft engines and other building and aerospace components — intact.
The Sikorsky decision runs counter to the statements that Mr Hayes made at an investor day in December, when he insisted Sikorsky was not for sale but noted that anything was for sale for the right price. Mr Hayes took over on November 24 from Louis Chênevert following his abrupt and so far unexplained resignation.
"This is part of the ongoing portfolio review process that we began after I took over as CEO," Mr Hayes said. "As we looked at the business around Sikorsky, we became convinced internally that, while Sikorsky is a great helicopter company, it probably didn't fit into the UTC portfolio."
Sikorsky — which builds the Marine One helicopters that US presidents use as well as the Black Hawk and some civilian helicopters — built entire aircraft while other parts of UTC provided only systems to other suppliers, Mr Hayes said.
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"We're primarily a systems provider, be that aircraft systems or systems in commercial buildings," Mr Hayes said. "Those businesses have a decidedly different portfolio than the platform business that is Sikorsky."
Sikorsky recorded operating profits of $219m on $7.45bn in sales for 2014. The profits were depressed by $466m of one-off charges.
The business was a "10 per cent margin" company, Mr Hayes said.
"It has the potential to grow but it has a big single customer in the US Department of Defense for two-thirds of its sales and the margin potential is just not what you would expect from a UTC-type business," he said.
UTC has hired JPMorgan to advise it on the sale or spin-off of Sikorsky.
Part of the reason for keeping the rest of the business together was that it had far more financial capacity as a single group than if split up, said Mr Hayes, who was UTC's chief financial officer before becoming CEO.
UTC would start work on a spin-off but would also consider a sale of Sikorsky, Mr Hayes said. A non-US buyer was a possibility, although such a transaction would need approval from the Pentagon.
The Pentagon seeks to preserve competition in key areas, meaning that it would be unlikely to approve the sale of Sikorsky to Boeing — which supplies Chinook helicopters — or another major manufacturer of military rotorcraft.
Mr Hayes said in December that UTC's recent performance had "not been very good" and vowed to improve it. He said on Wednesday that there was no immediate sign of attractive acquisition targets and the best use of the cash raised from the Sikorsky disposal might be to repurchase UTC shares.