Manchester – Alpha Flying Inc., which runs the PlaneSense fractional airplane-ownership program, has started work on a new general aviation hangar and a support building at its new home at Portsmouth International Airport at Pease, the company said.

The $13 million project, which will house the firm's aircraft maintenance operations, should be finished in October. Space considerations played a key role in the Londonderry-based company's decision to build the aviation complex. Over the next two years, Alpha Flying's fleet will increase from 25 to 37 planes, and is projected to reach 50 planes by 2010. It now leases space at Manchester-Boston Regional Airport for aircraft storage and maintenance.

"We've been very happy in Manchester," said George Antoniadis, Alpha Flying's president and chief executive. But, he added, "We need more space; it is not available (in Manchester). Pease is also a viable airport for us and we look forward to making it our new home."

Fractional airplane-ownership programs have become popular the past few years, giving business executives and those who can afford it the benefits of private plane use without the hassle and expense related to outright ownership. Alpha Flying's flight management and operations activities are run out of its Londonderry headquarters.

As Antoniadis put it, Alpha Flying Inc.'s PlaneSense program, based entirely at Manchester's airport and serving the eastern United States, provides its customers with double economies of scale. Through buying an interest in one of PlaneSense's aircraft, the customer gets access to all the planes in its fleet. That lets users buy only the flight time that they need, while the planes are run as efficiently as possible.

The minimum purchase in PlaneSense's program is a one-eighth share of an aircraft -- in this case, a Pilatus PC-12 single-engine turboprop from Pilatus Aircraft Ltd., the Swiss aircraft manufacturer.

That will cost $476,000, plus a monthly management fee of $6,850 and an hourly flight-time fee of $650. The fees entitle the buyer to 90 hours of flight time per year -- and guaranteed service upon request. With just eight hours' notice, PlaneSense can have a plane at any point east of the Mississippi River.

The company's aviation complex at Pease will be about 88,000 square feet in all; about 40,000 square feet for the hangar and 44,000 square feet for the attached support building.

It will serve as home not only to Alpha Flying's maintenance operation, but also Atlas Pilatus Center Inc., an affiliated company providing service for Pilatus aircraft. Alpha Flying has the world's largest fleet of Pilatus PC-12 aircraft, according to Antoniadis.

Pro Con Inc. is the architect and project manager for the development, located at 115 Flight Line Road in Portsmouth.