Pilot Dan Immel of Gig Harbor and Darrel Birkes, 62, of Portland died in the crash.
The Boeing-made Tandem-rotor chopper was taking off from an airport in Peru when it crashed. All seven in the helicopter died. The other passengers were from Peru, and the United States, officials said.
The helicopter was operated by the Columbia Helicopter Company out of Aurora, Ore., and was working near Pucallpa, Peru under the contract to support petroleum exploration operations, officials with Columbia Helicopters said.