SpaceX launch today
Discussion
Launch today at 17:00 BST - video here http://www.spaceflightnow.com/falcon9/006/status.h...
1st stage is programmed to do a deceleration burn at altitude to minimise stress on the stage as it re-enters the atmosphere, then decelerate to 0 just before splashdown. Hope it all works !
1st stage is programmed to do a deceleration burn at altitude to minimise stress on the stage as it re-enters the atmosphere, then decelerate to 0 just before splashdown. Hope it all works !
GrumpyTwig said:
'awaiting vehicle downlink'.......
I appreciate it's working against a pretty difficult set of extremes of speed, heat and g-forces but I guess their own data feeds aren't as intermittent as the video feed?
"Loss of downlink" is usually a sign of disaster. In this case it just means loss of the TV signal - I hope.I appreciate it's working against a pretty difficult set of extremes of speed, heat and g-forces but I guess their own data feeds aren't as intermittent as the video feed?
Eric Mc said:
GrumpyTwig said:
'awaiting vehicle downlink'.......
I appreciate it's working against a pretty difficult set of extremes of speed, heat and g-forces but I guess their own data feeds aren't as intermittent as the video feed?
"Loss of downlink" is usually a sign of disaster. In this case it just means loss of the TV signal - I hope.I appreciate it's working against a pretty difficult set of extremes of speed, heat and g-forces but I guess their own data feeds aren't as intermittent as the video feed?
I'd have called it a bit of an anticlimax really. Should have just filmed it in Kerbal Space Program instead
)SpaceX CEO Elon Musk says the Falcon 9 rocket accomplished all of its primary objectives on today's launch, placing its payloads in an accurate orbit over Earth's poles and successfully demonstrating the launcher's upgraded engines, flight computer and stage separation system.
But two secondary objectives on the flight were not met.
SpaceX programmed the Falcon 9's first stage to fire its engines two more times after separating from the Falcon 9 upper stage about three minutes after liftoff.
The first burn went well, placing the empty rocket stage on a trajectory back into the atmosphere. Musk said mission control received data from the rocket throughout re-entry, but a second engine restart put the rocket into a spin, causing its engine to prematurely cut off. The stage crash into the Pacific Ocean a few hundred miles south of Vandenberg Air Force Base, Calif.
Going into the flight, Musk put low odds on a successful retrieval of the first stage intact on Sunday's launch. He told reporters a few minutes ago that recovery crews picked up parts of the Falcon 9's interstage, engine section and composite overwrapped pressure vessels.
After releasing the mission's satellite payloads, the Falcon 9's second stage Merlin 1D engine was supposed to reignite to test its ability to restart in space. But the engine detected a problem during the restart and aborted the burn.
Musk said SpaceX engineers believe they understand the problem and it could be fixed in time for the Falcon 9's next launch with the SES 8 communications satellite from Cape Canaveral, Fla. The SES 8 mission requires two upper stage burns to put the spacecraft into an oval-shaped geostationary transfer orbit.
But two secondary objectives on the flight were not met.
SpaceX programmed the Falcon 9's first stage to fire its engines two more times after separating from the Falcon 9 upper stage about three minutes after liftoff.
The first burn went well, placing the empty rocket stage on a trajectory back into the atmosphere. Musk said mission control received data from the rocket throughout re-entry, but a second engine restart put the rocket into a spin, causing its engine to prematurely cut off. The stage crash into the Pacific Ocean a few hundred miles south of Vandenberg Air Force Base, Calif.
Going into the flight, Musk put low odds on a successful retrieval of the first stage intact on Sunday's launch. He told reporters a few minutes ago that recovery crews picked up parts of the Falcon 9's interstage, engine section and composite overwrapped pressure vessels.
After releasing the mission's satellite payloads, the Falcon 9's second stage Merlin 1D engine was supposed to reignite to test its ability to restart in space. But the engine detected a problem during the restart and aborted the burn.
Musk said SpaceX engineers believe they understand the problem and it could be fixed in time for the Falcon 9's next launch with the SES 8 communications satellite from Cape Canaveral, Fla. The SES 8 mission requires two upper stage burns to put the spacecraft into an oval-shaped geostationary transfer orbit.
The idea of recovering booster rockets by allowing them to land vertically on legs under their own rocket power is a tricky one to accomplish.
I'll be amazed if and when anyone achieves this. I think a parachute and perhaps cushioning rocket (such as used in Soyuz capsule recovery) might be less risky.
I'll be amazed if and when anyone achieves this. I think a parachute and perhaps cushioning rocket (such as used in Soyuz capsule recovery) might be less risky.
Eric Mc said:
I still think my idea of a parachute with "cusioning" rockets is cheaper, simpler and more reliable.
Trying to make a tall object like a rocket stage settle back down safely on its legs on a possibly uneven landing surface after a ballistic re-entry is going to be a tall order.
They tried parachutes on the first couple of flights without success IIRC. The extra weight, complexity, cost and lack of control of parachutes together with their unreliability was what persuaded them to try this instead.Trying to make a tall object like a rocket stage settle back down safely on its legs on a possibly uneven landing surface after a ballistic re-entry is going to be a tall order.
http://www.bbc.co.uk/news/science-environment-2433...
Musk said:
To this end, Sunday’s first-stage was commanded to reignite three of its nine engines after separation from the rocket’s upper-stage in an attempt to slow its return to Earth.
Then, as the stage got closer to the Pacific Ocean, it fired up a fourth engine to limit the descent speed still further.
SpaceX CEO and chief designer Elon Musk promises to post video on the web later this week showing what happened.
Although the stage lost some stability as it approached the water, the entrepreneur expressed great satisfaction with the way the experiment went.
"If things go super-well then we will be able to refly a Falcon 9 stage before the end of next year"
“In this case, the boost stage did not have landing gear, which helps essentially to stabilise the stage like fins on an aircraft.
“The stage actually ended up spinning to a degree that was greater than we could control with the gas thrusters, and it centrifuged the propellant. It caused the boost stage to run out of propellant before hitting the water. So it hit the water relatively hard.
“We’ve recovered portions of the stage, but the most important thing is we believe we now have all the pieces of the puzzle.”
Then, as the stage got closer to the Pacific Ocean, it fired up a fourth engine to limit the descent speed still further.
SpaceX CEO and chief designer Elon Musk promises to post video on the web later this week showing what happened.
Although the stage lost some stability as it approached the water, the entrepreneur expressed great satisfaction with the way the experiment went.
"If things go super-well then we will be able to refly a Falcon 9 stage before the end of next year"
“In this case, the boost stage did not have landing gear, which helps essentially to stabilise the stage like fins on an aircraft.
“The stage actually ended up spinning to a degree that was greater than we could control with the gas thrusters, and it centrifuged the propellant. It caused the boost stage to run out of propellant before hitting the water. So it hit the water relatively hard.
“We’ve recovered portions of the stage, but the most important thing is we believe we now have all the pieces of the puzzle.”
ninja-lewis said:
Eric Mc said:
I still think my idea of a parachute with "cusioning" rockets is cheaper, simpler and more reliable.
Trying to make a tall object like a rocket stage settle back down safely on its legs on a possibly uneven landing surface after a ballistic re-entry is going to be a tall order.
They tried parachutes on the first couple of flights without success IIRC. The extra weight, complexity, cost and lack of control of parachutes together with their unreliability was what persuaded them to try this instead.Trying to make a tall object like a rocket stage settle back down safely on its legs on a possibly uneven landing surface after a ballistic re-entry is going to be a tall order.
What's to control with a parachute?
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