The sudden announcement Thursday that Gov. Rendell has given up on converting the closing Willow Grove Naval Air Station into a hub for emergency and defense services threw the future of the 1,100-acre site again into question.

Two competing aims are now in play: the Navy's mandate to maximize profit - perhaps by selling most of the site to developers - and residents' ideas for something more idyllic than the old airfield.

An insider said today that a compromise is likely.

"It needs to be a mixture of things," said W. William Whiteside, chairman of the Horsham Land Reuse Authority, a township-created panel helping shape the base's redevelopment. "There needs to be some sort of business development there to provide income for the township and the school district. And we have to make sure that there's a certain amount of open space."

The outcome could radically reshape the sprawling, 64-year-old facility - and its 8,000-foot airstrip, which for years hosted the popular Willow Grove Air Fest.

"If there's not going to be a military flying mission there, I don't see the need for an airstrip," Whiteside said.

Rendell, who fought the base's closure since the Defense Department announced it in 2005, said he would like the federal government to choose Willow Grove as the site for one of six National Emergency Centers, should legislation to create them pass.

While the plan for a state-administered facility was still a concern, the Horsham authority's central function was making sure that the joint facility's planners heard local worries about potential new air traffic and other changes.

One such meeting happened just Tuesday, Whiteside said, and no one present knew that Rendell was abandoning the idea.

"It was a complete surprise," he said, "because we had been working with them throughout the process."

Now, the nine-member committee - composed largely of Horsham-area political and business leaders - shifts its focus to getting the base back on track for the formal closure that Rendell and others spent years fighting.

"It's a little bit convoluted, but we're moving back to where we started five years ago," Whiteside said.

Asked about the base's future, a Defense Department spokesman said only that Secretary Robert Gates would "respond to Gov. Rendell as appropriate" about the change of plans.

Whiteside said the Horsham group does not have another base's closure specifically in mind to model its plans upon, but he added that among the group's chief concerns is making sure the base's redevelopment does not lead to the arrival of new commercial flights.

"There's still a runway there, so there's still a process we need to go through to protect us from that," Whiteside said.

Contact staff writer Derrick Nunnally at 610-313-8212 or dnunnally@phillynews.com.