Space Launch System - Orion
Discussion
Will it be crossing the UK south coast?
That seems quite a high angle of inclination to the equator for a flight to the moon. Launches to the ISS can indeed pass over the UK, which makes sense as the ISS tracks over the UK too. If you are heading for the moon, to conserve fuel and energy you would generally be sticking to a more equatorial plane.
I know they want to eventually land at the lunar south pole, which could mean a more inclined departure track to the moon than the tracks taken by Apollo missions.
That seems quite a high angle of inclination to the equator for a flight to the moon. Launches to the ISS can indeed pass over the UK, which makes sense as the ISS tracks over the UK too. If you are heading for the moon, to conserve fuel and energy you would generally be sticking to a more equatorial plane.
I know they want to eventually land at the lunar south pole, which could mean a more inclined departure track to the moon than the tracks taken by Apollo missions.
Beati Dogu said:
The US Navy is still doing the capsule recovery though, just like old times. This time with LPD ships, these Landing Platform Dock ships normally support amphibious operations, so they have a floodable well deck area at the back where they can haul the Orion capsule in.
I was talking about the tracking ships rather than recovery ships. NASA used a small fleet of tracking ships which covered the "blank" spots in their global tracking network - chiefly the Indian and Pacific Oceans.
They also had planes in the air doing tracking too, known as ARIA aircraft (Apollo Range Instrumented Aircraft)
With the insertion of the Tracking Data and Relay Satellites since the mid 1980s, there has been no need for these ships or aircraft.
I think that there has been some funding for new build engines. It will all depend on how many missions they envisage for Artemis and how well they can persuade Congress to keep the funding going.
One major difference with the use of these engines on SLS is that they won't be reusable, so they can operate them at higher thrust settings than when fitted to the Shuttle. A lot of test firing of the engines was making sure that they could operate at these higher levels of output for the required 8 minutes to orbit.
One major difference with the use of these engines on SLS is that they won't be reusable, so they can operate them at higher thrust settings than when fitted to the Shuttle. A lot of test firing of the engines was making sure that they could operate at these higher levels of output for the required 8 minutes to orbit.
Dog Star said:
While this launch is great news and inspiring, it does strike me that NASA should be at the forefront of encouraging innovations like Starship, promoting efficiency, reusability and ultimately driving down cost. This should be core.
It’s disappointing to see that chucking billions of dollars worth of mankind’s finest engineering into the ocean is still happening.
Guess from where SpaceX has received a large chunk of funding?It’s disappointing to see that chucking billions of dollars worth of mankind’s finest engineering into the ocean is still happening.
Simpo Two said:
The Saturn V first stage used refined kerosene and liquid oxygen, got men to the moon and seemed very reliable. Why were those propellants abandoned for H2, O2 and strap-on boosters that seem like an accident waiting to happen (and did)?
From Wiki: 'All three stages used liquid oxygen (LOX) as the oxidizer. The first stage used RP-1 for fuel, while the second and third stages used liquid hydrogen (LH2). Whereas LH2 has a much higher energy density to be lifted into orbit by mass, RP-1 has a much higher energy density by volume. Consequently, RP-1 was chosen for the first stage propellant because the volume of LH2 required would have been more than three times greater and would have created much higher aerodynamic drag during the boost phase through the atmosphere.'
The second and third stages of the Saturn V did indeed use LOX and LOH. It was just the first stage that used LOX and Kerosene (RP1). However, whilst the first stage was firing, the second and third stages were just sitting there doing no work - so were, in effect, dead weight until they were brought into play. From Wiki: 'All three stages used liquid oxygen (LOX) as the oxidizer. The first stage used RP-1 for fuel, while the second and third stages used liquid hydrogen (LH2). Whereas LH2 has a much higher energy density to be lifted into orbit by mass, RP-1 has a much higher energy density by volume. Consequently, RP-1 was chosen for the first stage propellant because the volume of LH2 required would have been more than three times greater and would have created much higher aerodynamic drag during the boost phase through the atmosphere.'
The Shuttle went with a different set up - LOX and LOH burning simultaneously with two Solid Rocket Boosters. The total thrust of the Shuttle (and SLS) at lift off is over 7.5 million pounds, which is pretty similar to what the first stage of the Saturn V was putting out. The difference with the Shuttle and SLS is that ALL the motors of ALL the stages are running at the same time so the weight of the system (which is mostly fuel) is going down much more rapidly. This makes for a more efficient rocket.
SRBs are, on the whole, pretty reliable - as long as the fundamental design is right and they are operated within the correct parameters.. The problem with the one incident where an SRB failed is precisely because NASA ignored their own safety rules. When those SRBs were designed, it was a given that they would not be operated under certain outside air temperatures. On that morning, due to scheduling pressures, they chose to waive one of their own "no launch" rules. It was a management decision that destroyed Challenger, not a design fault.
Beati Dogu said:
It’s like that with any government project - civilian or military. It’s the main reason they cost so damn much.
Funnily enough, yesterday was the 60th anniversary of Kennedy’s “We choose to go to the Moon" speech.
And the odd thing was, they were already designing both the moon rocket AND the spacecraft BEFORE Kennedy made that speech - for all the reasons given in that excellent post by MartG.Funnily enough, yesterday was the 60th anniversary of Kennedy’s “We choose to go to the Moon" speech.
The perils of launching from Florida.
SpaceX were a bit lucky with their Falcon Heavy launch in that they were able to get it off in a weather window. Also, the Falcon rocket is now very mature and the prep time for each launch is relatively short and possible technical problems are well known and understood. They had their big bangs and explosions early in their programme, don't forget.
Artemis is bigger, heavier, complex (too complex perhaps) and has never been flown before so naturally there will be extreme caution with this first launch.
SpaceX were a bit lucky with their Falcon Heavy launch in that they were able to get it off in a weather window. Also, the Falcon rocket is now very mature and the prep time for each launch is relatively short and possible technical problems are well known and understood. They had their big bangs and explosions early in their programme, don't forget.
Artemis is bigger, heavier, complex (too complex perhaps) and has never been flown before so naturally there will be extreme caution with this first launch.
Simpo Two said:
Eric Mc said:
Just like the Shuttle - on which it is based.
QED!And think of the more current problems aflicting Boeing's Starliner.
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