The nation's air transportation system remained grounded Wednesday, with federal officials giving no indication when things could get back to normal.

        The Federal Aviation Administration issued an unprecedented “ground stop” Tuesday morning after it was discovered that the planes involved in the crashes in New York and Washington were hijacked.

        U.S. Transportation Secretary Norman Mineta said that those planes that were diverted to airports other than their intended destinations would be allowed to continue, and airlines would be allowed to reposition empty planes to get ready for the start-up.

        But he also stressed that the ban on normal flying by airlines, freight companies and private aircraft remained in place.

        “I can't give you a date or time as to when we will be back in operation,” Mr. Mineta said. “We're trying to make that determination based on the safety and the security of the airline passengers.”

        The continued ban stranded thousands of travelers nationwide for the second straight night. That included about 1,200 at the Cincinnati/Northern Kentucky International Airport — Delta Air Lines' second-largest hub, the home of Delta-owned regional carrier Comair and the 16th-busiest airport in the country.

        Delta and Comair have tentatively canceled all regularly scheduled flights through 5 a.m. today, although airline officials had yet to receive clearance from the FAA to start any flights as of Wednesday evening. And there was no word as to whether any of the diverted flights were allowed to continue Wednesday.

        About 124 planes were grounded locally, including about a dozen that were headed elsewhere but landed here instead. Most passengers stranded locally had found hotel rooms somewhere in the Tristate, but some had elected to spend the night at the airport.
       

No way to leave

        Mark Bergeron was traveling from Anchorage, Alaska, when the order forced his flight to land at the local airport. His final destination is London, and with no clear answer as to when he can resume his journey, he was looking for options.

        “It's a weeklong drive back (to Alaska),” said Mr. Bergeron, 22. “And I'm not 25, so I can't rent a car.”

        The added delay was more than just an inconvenience for Ray and Pat Klein of Union. The couple was scheduled to depart for Seattle on Wednesday for a a nonrefundable seven-day cruise to Alaska set to leave today.

        But the Kleins are far more concerned about the nation than themselves.

        “It's the uneasiness about the status of the country,” Mr. Klein said. “The thrill of going just isn't there ... is a vacation appropriate?”

        DHL Worldwide Express, which operates its main U.S. hub at the local airport, has been able to transfer some domestic shipments to ground transportation, but all international parcels are still sitting at the sorting facility in Erlanger.

        The U.S. Postal Service, which ships about 20-25 percent of the nation's mail on airliners, has also shifted to ground transportation, meaning there will be some delays, spokesman Ray Jacobs said.

        United Parcel Service also has been able to shift some of its business to its extensive ground fleet, but has been forced to shut its main air freight hub in Louisville, officials for the Atlanta-based firm said.
       

Amtrak doubles sales

        As for other modes of transportation, Amtrak officials reported that sales had almost doubled, although seats were still available.

        The region's major rail freight companies, CSX — which operates a major rail yard in Queensgate — and Norfolk Southern, said things were back to normal Wednesday after brief disruptions Tuesday to conduct security checks.

        Area rental car agencies reported brisk business Wednesday, with the local Avis affiliate selling out late in the afternoon. That company was allowing people to rent cars one-way for the normal daily rate to return home.

        Staff writer Tom O'Neill and the Associated Press contributed.

At a glance
Attacks are topic No. 1 in classrooms
Body recovery part of work of NYC crews
Constituents' emotions unmitigated
Different faiths, all drawn to pray
Family clings to details of missing woman's fate
Jews seek normalcy
Local firefighters on task force joining rescue efforts
Muslims urged to give aid
No date, time for nation's air travel to resume
Notebook
Outpouring of donations keeps blood supply steady
Relatives wait for word, pray
Stranded travelers find help in Florence
Tightened air security will be norm
Travelers wait, pray in deserted airport
Work resumes, but life is different
Wright-Patterson medical personnel join effort
PULFER: Cell phones
RADEL: Tristate sprouts flying flags
Reports bring sweep of river
Court upholds stay for Byrd
Luken suggests raises for cadets
Luken unused to second place
Primary results
Council halts bid for road-extension vote
Superintendent's contract extended
Tristate A.M. Report
Woman shot outside school as it lets out