Did you catch sight of the Army Stryker vehicles heading down H-2 Freeway in late January?

If you blinked, you missed them.

Now they're gone — for about the next year and a half.

Keeping the vehicles off public roads has been an Army priority, and judging by how little they are spotted, they've done a pretty good job.

Maintaining a low profile when a vehicle weighs 19 tons, sports eight large tires and looks vaguely like a tank is not easy under any circumstances, but as a result of a previous deployment to Iraq and one upcoming, the vehicles will be out of the state for a combined total of more than three years.

The Stryker brigade and its 4,300 soldiers and about 330 eight-wheeled Stryker vehicles soon will be taking part in six weeks of training at the National Training Center in California ahead of a summer deployment to Iraq.

The vehicles convoyed to Pearl Harbor in late January for shipment to the West Coast. They won't be shipped back to Hawai'i before the deployment to Iraq, said Lt. Col. David P. Doherty, a spokesman for the 25th Infantry Division.

The 599th Transportation Group had loaded more than 2,400 pieces of cargo — including the Strykers — for shipment at Pearl Harbor by Feb. 4.

The Stryker vehicles returned to Hawai'i last spring and summer after an even longer deployment to Iraq and absence from the state. The vehicles were shipped in August 2007 for training in California and then were sent on to the Middle East.

The Strykers most recently were driven down to Pearl Harbor between 11 p.m. and 3 a.m. to minimize traffic interference.

"The 25th Infantry Division goes to great lengths to ensure that the deployment of soldiers, equipment and vehicles is done safely, effectively and with minimum impact on the local community," Doherty said.

Even rarer than the sight of a troop-carrying Stryker is the Mobile Gun System, a variant mounting a 105mm gun that makes the vehicle even more tank-like.

Col. Malcolm Frost, the Stryker brigade's commander, says he is authorized to have nine, but actually has three.

"That's being worked by the folks that field the Strykers based on the distribution. There were some initial glitches that they worked through on those and now they are sending them out to the Stryker brigades," Frost said recently. "It's going to take a little bit to catch up to what we're authorized."

In Iraq, Frost expects his soldiers and Strykers to be spread out across several provinces as an "advise and assist" unit working with Iraqi army and government officials.