European pilots who are protecting U.S. skies as part of a historic NATO deployment say they were surprised to get the assignment but do not have any problem carrying it out.

Five Airborne Warning and Control Systems aircraft from a NATO base in Germany arrived at Tinker Air Force Base last week along with 180 crew members and support personnel from 13 different countries.

This is the first time that NATO airplanes have ever conducted patrols over the United States. They are helping replace U.S. airplanes supporting the military action in Afghanistan.

Canadian Air Force Col. Jim McNaughton, who heads the NATO detachment, said in a news conference Tuesday that his people are working well with the U.S. Air Force.

"Because of the training we do together, it is all a seamless organization," he said.

A Greek pilot who identified himself as Lt. Col. Periulis said:

"I did not expect this ... but the world now is very different."

Many members of the NATO group used only their last names for security purposes.

The NATO flight crews can all speak English. The five airplanes look like U.S. AWACS planes except they carry NATO markings instead of U.S. Air Force insignias.

While most of the NATO forces in Oklahoma are military, there are some civilians attached to the group.

Emil, from Holland, has worked for NATO for 18 years and is the civilian maintenance chief for the five airplanes.

"America is a big country and can handle themselves, but we are glad to be able to help," he said.

The NATO planes are helping with NORAD patrols that were instituted after the Sept. 11 terrorist attacks in New York and Washington, and are also working in conjunction with the Federal Aviation Administration.

The airplanes, which are crammed with sophisticated electrical equipment for surveillance, are able to monitor battles on the ground or threats in the air.