Undocking from the International Space Station is scheduled for 7:34 p.m. EDT Saturday.
With a hurricane headed towards Florida, however, it's unclear if the weather will cooperate with the plan.
"We're watching those closely, mostly to maintain awareness and see the trends and understand what the timeline would be if our recovery out of the water, for example, was delayed a little bit", he said. "We have plenty of opportunities here in August, and we're in no hurry".
The astronauts said they'll have seasick bags ready for the landing. Assuming there are no glitches with the remainder of Hurley and Behnken's demonstration mission, dubbed Demo-2, the company will move ahead with Crew Dragon's first "operational mission".
He said the astronauts could always stay on the space station longer. The last US space return by sea was the joint Apollo-Soyuz docking mission, which ended with the Apollo capsule's return in July 1975 northwest of Hawaii. It was the final flight of the Apollo spacecraft.
SpaceX and NASA, in preparation for the upcoming undocking of the DEMO-2 Crew Dragon from the International Space Station, are continuing to monitor weather patterns in the Atlantic Ocean and Gulf of Mexico.
Just in case, Hurley said Friday, "there are bags if (we) need them and we'll have those handy, we'll probably have some towels handy as well". We'll probably have some towels handy, as well.
NASA astronauts Doug Hurley and Bob Behnken are making preparations for their historic return to Earth Sunday. The prime target is off the coast of Panama City, halfway between Tallahassee and Pensacola. Once it's flying free, the ship is programmed to fire its engines more aggressively to put it on the path toward its splashdown location off the Florida coast.
It will be NASA's first ocean splashdown in 45 years and the first piloted re-entry of a Crew Dragon capsule.
The Crew Dragon capsule has two sets of parachutes that slow the spacecraft down as it travels through the Earth's atmosphere. The recovery vessel is expected to secure the astronauts within an hour. And since then, the capsule has been docked at the space station which allowed Hurley and Behnken to chip in with spacewalks and experiments. SpaceX's next astronaut flight is targeted for the end of September. It will be the last decisive step before SpaceX joins hands with NASA for its Commercial Crew Program.
Crew members for that mission are to be NASA astronauts Mike Hopkins, Victor Glover and Shannon Walker, along with Soichi Noguchi from the Japan Aerospace Exploration Agency.
For the past nine years, American astronauts traveled exclusively on Russian rockets Soyuz rockets, for a price of around $80 million per seat. After Behnken and Hurley return to Earth, their spacecraft will undergo a series of inspections in Florida to assess how the vehicle performed throughout its flight.