TheThis brought astronauts Douglas Hurley and Robert Behnken into space and made for a somewhat rougher ride than expected in the later phases of ascending to orbit. However, both said they enjoyed their historic trip on Monday and were amazed at a silence .
And yes, the Crew Dragon brought a “new car smell” into the laboratory complex.
“It absolutely did,” said station commander Chris Cassidy, the only American on board the station, until Hurley and Behnken arrived on Sunday. “When we opened this hatch, you noticed that it was a brand new vehicle, with smileys on the other side, smileys on mine, as if you had bought a new car, the same reaction.
“Wonderful to see my friends and wonderful to see a brand new vehicle,”
from Pad 39A at the Kennedy Space Center on Saturday afternoon, strapped into a Crew Dragon capsule on a Falcon 9 rocket.
It was the first piloted launch into orbit on American soil in almost nine years, the first flight of a SpaceX rocket with astronauts and the first new spacecraft with crew to have flown in space since the first shuttle mission 39 years ago .
Both Hurley and Behnken are space shuttle veterans who are familiar with the initially rough ride when the orbiter’s powerful solid fuel boosters fired and the transition to a much quieter experience after the boosters were dropped and only the liquid ones The ship’s main engines were running.
The Falcon 9 is a two-stage rocket powered by liquid oxygen and kerosene. The first stage, with nine Merlin engines, generates 1.7 million pounds of thrust when lifted. The second stage of the rocket is powered by a single Merlin vacuum engine.
“Shuttle had solid rocket boosters that burned very hard in the first two and a half minutes,” said Hurley. “The first stage with Falcon 9 … was a much quieter ride.”
He said switching off the first stage motors, separating the first and second stages, and then firing the single upper stage engine was similar to the memorable start sequence depicted in the film “Apollo 13”.
“So the first stage motors stopped, and then it took some time between disconnecting the booster and starting the Merlin vacuum motor,” said Hurley. “At this point, we’re going from about three Gs (three times the normal gravity on the ground) to zero Gs, I don’t know, probably half a second, and then when that Merlin vacuum motor fires, we start to accelerate again.
“It got a little rougher with the Merlin vacuum motor, and it will be interesting to talk to the SpaceX people to find out why it was a little rougher on the second leg than the shuttle on these three main motors.”
The Crew Dragon is designed so that it can meet and dock autonomously with the space station without direct input from the crew. For the first piloted test fight, Hurley took over manual control twice to check whether astronauts could fly the ship themselves if necessary.
There were no problems, and when the crew moored at the station on Sunday morning, Hurley and Behnken could not see the impact.
“What we both really noticed, and we mentioned it once we docked is that we didn’t feel the docking,” said Hurley. “It was just so smooth.”
Hurley is a former test pilot and Behnken, who holds a PhD in mechanical engineering from Caltech, is an experienced Air Force flight test engineer. They were selected in part for the first piloted Crew Dragon flight so that they could apply these skills to the evaluation of the spacecraft before it began operational missions to the space station in late summer.
“We are here to evaluate how the mission is doing and so far it has been absolutely spectacular,” said Hurley. “It’s a very clean vehicle. It does everything we need for this mission, so we’re very happy with this part.”
Including the operation of the Crew Dragon toilet. Although he didn’t provide any details, Hurley said it was “very similar to what we were used to in the Space Shuttle and it worked very well. We had no problems with it.”
NASA managers have not yet decided how long Hurley and Behnken will remain in orbit. The Crew Dragon is certified for up to four months in space. However, the crew can be ordered home earlier depending on how the space environment affects the capsule’s solar panels, the weather in the Atlantic Ocean splash zone, and other factors.
Not knowing when they could come home is “a bit strange,” said Behnken. “I’m trying to explain it to my only six year old son and from his point of view he’s just excited that we’ll get a dog when I get home. So he accepts this insecurity and continues to send messages to me while I’m in orbit . “
The mission is expected to take at least six weeks and possibly up to four months, far longer than its relatively short shuttle flights. Contact with her women, the two experienced astronauts and her two sons is a top priority for Hurley and Behnken.
“One of the things I was most happy about (after the start) was that I could phone home,” said Behnken. “It’s been a long time since I started orbit, and I have a little boy who was able to watch me for the first time in his life. And I just wanted to understand what his experience was, and I share that a bit him.
“He was able to make the trip back to Houston after watching the docking from below in Florida and was pretty excited about it all, so it was wonderful for me.”