NASA and SpaceX took yet another step toward a historic crewed spaceflight next month, this time prepping for a worst-case scenario on the launch pad.

NASA astronauts Bob Behnken and Doug Hurley are scheduled to launch toward the International Space Station (ISS) aboard SpaceX's Crew Dragon capsule in mid- to late May. The test mission, known as Demo-2 , will be SpaceX's first-ever crewed flight and the first orbital human mission to lift off from American soil since the retirement of NASA's space shuttle fleet in July 2011.

Preparations for the epic flight are in full swing at NASA's Kennedy Space Center (KSC) in Florida, and an important safety test occurred on Friday (April 3). NASA and SpaceX workers together performed an "emergency egress" drill, practicing all the steps necessary to whisk astronauts to safety should a serious problem arise just before launch at KSC's historic Pad 39A .

Video: Watch SpaceX's Demo-2 Crew Dragon spin in a critical prelaunch test

On April 3, 2020, NASA and SpaceX completed an end-to-end demonstration of the teams’ ability to safely evacuate crew members from the Fixed Service Structure during an emergency situation at Launch Complex 39A at NASA’s Kennedy Space Center in Florida. The test will help the teams prepare for Demo-2, SpaceX’s first crewed flight, which is scheduled to launch in mid- to late May. (Image credit: SpaceX)

"Teams rehearsed locating injured personnel on the 265-foot-level of the launch tower, loading them into the pad's slidewire baskets and safely descending the tower, then successfully loading the injured participants into Mine Resistant Ambush Protected (MRAP) vehicles staged at the pad perimeter," NASA officials wrote in an update today (April 7).

If Demo-2 goes well, SpaceX will be clear to start flying operational missions under a $2.6 billion contract the company signed with NASA in 2014. Four people — NASA astronauts Michael Hopkins, Victor Glover Jr. and Shannon Walker and Japanese spaceflyer Soichi Noguchi — will fly on that first contracted mission , the launch date for which has not yet been set.

Boeing also holds a NASA Commercial Crew contract, a $4.2 billion deal that the aerospace giant will fulfill using its CST-100 Starliner capsule. But Starliner isn't yet ready to carry astronauts. The capsule will first refly an uncrewed test mission to the ISS , after failing in an attempt to reach the orbiting lab in December 2019. (SpaceX aced its uncrewed ISS test mission, called Demo-1, in March 2019.)