TAMPA - Remember when developers proposed a bunch of new skyscrapers for Tampa?

With just a few exceptions, they didn't work out. Now, a few developers show signs of trying again in this post-tower-slump market.

This week, developers filed paperwork with the Hillsborough County Aviation Authority board at Tampa International Airport for height variances for four new towers in downtown Tampa, some nearly as tall as the city's tallest buildings.

Airport officials characterized this as a procedural step to forewarn them about tall buildings near air traffic patterns rather than any guarantee a tower would be built. And an attorney with one project described investors as patiently waiting for a rebound before going forward.

That said, here are the projects described in documents at the airport:

•A previously approved permit for twin 320-foot-tall residential and retail towers on three acres in downtown Tampa bordered by Brorein Street, Morgan Street and Channelside Drive, directly across the street from St. Pete Times Forum. The petitioner is Chaim Elkoby, Channelside Development LLC.

• One 557-foot-tall residential tower at the southeast corner of Morgan and Whiting streets in Tampa, where there is now a parking structure. The petitioner is Peter M. Gottshalk, The Tampa Downtown Invest Ltd.

•Gottshalk is also listed as applicant for a 551-foot-tall residential tower next door, bordered by Jefferson and Whiting streets. The application also lists S&H Bayshore Four Seasons Ltd. as the petitioner.

Keith Bricklemyer, a Tampa lawyer affiliated with those last two towers, said they are backed by several Swiss investors he described as "very patient."

Over several years, his duties have included maintaining the investors' rights to build potential towers, and the airport authority step was routine, Bricklemyer said.

"So if and when the time comes, everyone will be ready," he said. As for what the investors are waiting for, Bricklemyer said "demand. They're not going to start a project without the market turning around. Fortunately, they're able to be patient."

Attorneys and other representatives for other projects did not return calls seeking comment. Tampa building and construction officials said they had no information about any proposed towers.

None of the new potential towers would be Tampa's tallest, but some would come close. Exact statistics on Tampa's tallest buildings tend to vary with the source.

The 100 N. Tampa St. "Regions" tower is 42 stories tall, 38 stories aboveground and rises about 579 feet, or just a bit taller - depending on how the decorative gables are counted.

There is also the 42-story Bank of America Plaza, listed at 577 feet tall. If it had been built, a proposed Trump-branded condo tower on the Hillsborough River at Brorein Street would have been the tallest building at 593 feet.

Airport authority board members voted to approve the petitions for height-limit variances on these potential new towers after approvals by the Federal Aviation Administration.

What happens next is up to developers, airport spokeswoman Brenda Geoghagan said. They have 18 months before they need to reapply for another variance from the airport.

Reporter Richard Mullins can be reached at (813) 259-7919.