1.   Fears that crop dusting planes could be used to spread chemical or biological agents led the FAA to ground those planes on Sunday.

2.   Over the next few years, mechanical problems continued to ground the planes, as did abrupt changes in design.

3.   Tower Air refused to ground the plane.

4.   A day after regional airline Crossair officially took over collapsed national carrier Swissair, new financial difficulties threatened to ground planes again.

5.   Air Canada says it will ground its planes in the event of a strike and customers will need to seek other travel arrangements.

6.   FAA spokesman Les Dorr also said there was no reason to ground the plane.

7.   In a statement, Alaska Airlines said it would immediately ground any planes found to be potentially unsafe.

8.   It also said it would immediately ground any planes found to be potentially unsafe.

9.   The crew had been warned ice could form on the wings, but investigators said conditions were not harsh enough for authorities to ground the plane.

10.   The crew were told ice could form on the wings, but investigators said conditions were not harsh enough for authorities to ground the plane.