The federal government, buffeted by criticism of a decision to ground aging air tankers (search), announced Tuesday that it will contract for nearly 120 more aircraft to fight wildfires (search) this summer.

Heads of the Bureau of Land Management and the Forest Service (search) Tuesday defended the decision to ground 33 large firefighting air tankers — which are able to lay down large swaths of fire retardant — because of safety risks.

They also said they would contract with private companies for up to 38 air tankers and 71 large and medium-sized helicopters to take up the slack. The extra firefighting help will cost about $66 million.

The move, announced by the National Interagency Fire Center, comes amid heavy criticism from congressional leaders, firefighters and others in the West, where wildfires have burned through thousands of acres.

"These additional aircraft will enable fire managers to fully maintain their ability to stop nearly 99 percent of all fires on initial attack and continue to protect communities," Forest Service chief Dale Bosworth said in a statement.

The federal agencies also said that eight U.S. military C-130 aircraft equipped with a retardant-dropping system were available.

The suspension of the aging air tankers came after a recent National Transportation Safety Board report on three fatal air tanker accidents. All happened within the last 10 years.

The new aircraft will join a fleet of more than 700 firefighting planes and helicopters, officials said.