New York Senators Chuck Schumer and Kirsten Gillibrand are pushing to upgrade the Ski-Bird Fleet at Stratton Air National Guard Base in Glenville.

The aircraft at the base are reaching end of their life, according to Schumer. Some are up to five decades old.

These are the planes involved in Operation Deep Freeze, which are the research missions with the National Science Foundation in the North and South poles.

The senators are demanding the Air Force prioritize replacing the aircraft.

“These planes are used in everything from polar missions to scientific research, and are essential for maintaining America’s leadership in the Arctic as we compete with countries like China and Russia. The Air Force must prioritize a new fleet of LC-130H planes for the safety of our military personnel and efficacy of this critical mission,” Schumer said in a statement.

“These planes have reached the end of their lifespans, limiting our aircrews and risking American leadership in the Arctic,” Gillibrand said in a statement.

The fleet is one of the few ski-equipped aircraft capable of flying to the Arctic and Antarctica.