The company is aiming for the single-engine light helicopter market dominated by Airbus (>> Airbus SE), Textron's Bell Helicopter (>> Textron Inc.), Lockheed-Martin's (>> Lockheed Martin Corporation) Sikorsky and Italy's Leonardo (>> Leonardo).
Chief Executive Andreas Loewenstein, an ex-Airbus executive, said he expected the capital hike to be completed by early 2018. Rothschild is advising Marenco.
Reuters had earlier reported the plan.
Loewenstein said the market for versatile helicopters that can accommodate passengers, patients or payloads is ripe for a Swiss upstart with new technology since many existing helicopters' designs date to the 1970s.
"There's a great opportunity to become a challenger in this segment," Loewenstein said. "We aim to produce and sell well over 100 helicopters annually."
He estimated the market at 600-700 machines annually, led by Airbus.
Switzerland's long aviation history includes 78-year-old planemaker Pilatus.
Still, getting tiny Marenco off the ground means overcoming competition from well-known aerospace giants with enormous pricing power and vast maintenance networks, in an industry where surprises from complex technology often lead to cost overruns.
Loewenstein, whose helicopter is undergoing European Aviation Safety Agency certification, expects the capital increase's proceeds to cover needs until Marenco breaks even, planned for 2022.
His 5,500-pound aircraft seats eight, cruises at 260 km/h (162 mph) and will cost $3.3 million. Marenco makes components like rotor blades itself, while tapping suppliers for others, including turbines from Honeywell (>> Honeywell International).
"To be a helicopter maker, you must be capable of creating a production organisation, a support group and distribution," Loewenstein said. "We've begun building these elements and want to move swiftly to the global market."
Initial orders have come from Air Zermatt, whose services include rescuing imperilled climbers from Switzerland's 4,478-metre (14,692-foot) Matterhorn. Air Zermatt, which now flies Bell and Airbus aircraft, did not respond to a request for comment.
In all, Marenco has received down payments for 12 aircraft and more than 100 letters of intent, Loewenstein said, with half from the United States and the rest from Europe, Asia and South America.
The decade-old company, located on an ex-Swiss military airfield in the village of Mollis, has so far been bankrolled by Russian billionaire Alexander Mamut, who plans to remain on board.
New investors could include strategic partners or family offices, Loewenstein said.
"I'm not the owner, but I wouldn't rule out an IPO when the company is more mature," he said.
(Reporting by John Miller and Oliver Hirt in Zurich, Tim Hepher in Paris and Victoria Bryan in Berlin; Editing by Joshua Franklin and Michael Shields)
By John Miller and Oliver Hirt