SpaceX Tuesday...

[Toaster]

Mojocvh said:

Interesting Eric. What I fail to comprehend is the seeming opposition to spaceX's Ideal of reducing the cost of space exploration.

Obviously Musk has really got the establishment rattled with his forward leaning ideals. The US launcher field was pretty much a state funded closed shop. What we see are the old yesterdays men being wheeled out at every opportunity to decry the young interloper...

IMO, of course.

You may want to read up on some history as to where re-usable rockets came from and the Idea was long before Mr Musk was born, and like most ideas technology or materials have to catch up. Once again it the Germans (WW2) and Kraft Arnold Ehricke is one of those credited with the idea who also worked on projects for reusable rockets.

I doubt if the establishment is rattled as NASA provides funding to Space X as a contractor as One of the suppliers so there may be a little more forward thinking and risk management than you may think. and like all technology once its been done it gets copied BO and Space X are taking the risk but do you honestly think Boeing et al are not watching and considering how they will use the technology and their resources. ( I would say do you want to put a sock in it but that would be rude and a waste of a decent pair of socks)

[Eric Mc]

In the late 1960s a very interesting little book was published called "The Frontiers of Space". I used to pull it out of my local library on a regular basis. If I ever see it again I might buy a copy for myself. It was published by Blandford Press and was written by Kenneth Gatland. It featured lots of ideas for future Space Shuttle and reusable rocket stages - including single stage to orbit ideas.

What we are seeing today are the beginnings of the realisations of some of the ideas in this book.

[Scuffers]

Toaster said:

You may want to read up on some history as to where re-usable rockets came from and the Idea was long before Mr Musk was born,

nobody is suggesting otherwise, the simple facts are that SpaceX is the first to actually work on getting a commercially viable rocket system to achieve it.

Nasa spent billions going down the wrong route with the shuttle programme, they could have done far more with less money just keeping the Saturn 5 programme, you know, the rocket that 40+ years ago could put more mass into orbit than anything before or since, (Skylab anyone?)

[Toaster]

Scuffers said:

nobody is suggesting otherwise, the simple facts are that SpaceX is the first to actually work on getting a commercially viable rocket system to achieve it.

Nasa spent billions going down the wrong route with the shuttle programme, they could have done far more with less money just keeping the Saturn 5 programme, you know, the rocket that 40+ years ago could put more mass into orbit than anything before or since, (Skylab anyone?)

I was refering to this statement 'Obviously Musk has really got the establishment rattled with his forward leaning ideals.' clearly Mr Musk has the financial clout to make it happen, along with the technology that has been developed in other industries but I would argue he is just utilising ideals that were outlined long ago.

[Toaster]

Scuffers said:

Eh?

currently, we have

Orbital Sciences
SpaceX
Soyuz

I am not the program controller however as this link says

http://spider.seds.org/shuttle/iss-sche.html and you will find as an example a Mitsubishi rocket you will also find Boeing....

And whilst this may seem pedantic thats 3 organisations you have mentioned not Launch vehicles I was pointing out past and current launch vehicles that can deliver.

Edited by Toaster on Sunday 24th January 13:24

[Scuffers]

OK,sorry, missed Mitsubishi's H-II and Atlas.

that's 5...

[Toaster]

Scuffers said:

OK,sorry, missed Mitsubishi's H-II and Atlas. that's 5...

No problem i know its small numbers but as a % its quite large and apologies if I can be a bit pedantic

[Toaster]

ash73 said:

It did have a unique retrieval capability though, as demonstrated by STS-51-A here. I expect the military made use of that, too.

Interesting you chose the Palapa B2 there were two satellites insured by Lloyds of London the Underwriter was Stephen Merritt of Merritt Syndicates he led the case for Lloyds to underwrite the rescue so that NASA could go and get the satellites back, they could be retrieved checked and sold on ! If the rescue mission had failed Lloyds would have had to pay out for the Satellites and Launch costs.

I reckon thats true risk taking and in line with insuring good on the old clipper days

Edited to add this link http://www.joc.com/insurance-briefs_19860917.html

Edited by Toaster on Sunday 24th January 15:24

[Leithen]

Toaster said:

ash73 said:

It did have a unique retrieval capability though, as demonstrated by STS-51-A here. I expect the military made use of that, too.

Interesting you chose the Palapa B2 there were two satellites insured by Lloyds of London the Underwriter was Stephen Merritt of Merritt Syndicates he led the case for Lloyds to underwrite the rescue so that NASA could go and get the satellites back, they could be retrieved checked and sold on ! If the rescue mission had failed Lloyds would have had to pay out for the Satellites and Launch costs.

I reckon thats true risk taking and in line with insuring good on the old clipper days

His name was Stephen Merrett. I worked for him. He was a risk taker.

[Eric Mc]

ash73 said:

Scuffers said:

Nasa spent billions going down the wrong route with the shuttle programme

It did have a unique retrieval capability though, as demonstrated by STS-51-A here. I expect the military made use of that, too.

The military INTENDED to make use of this capability. In fact, the Russkies were worried that the US would use the Shuttle to capture RUSSIAN satellites and bring them back for analysis.

In then end, the US military realised that the capability to do this was actually very limited and fraught with danger. How many satellite retrieval missions were there in the entire programme - Two? Three?

[Eric Mc]

Eric Mc said:

ash73 said:

Scuffers said:

Nasa spent billions going down the wrong route with the shuttle programme

It did have a unique retrieval capability though, as demonstrated by STS-51-A here. I expect the military made use of that, too.

The military INTENDED to make use of this capability. In fact, the Russkies were worried that the US would use the Shuttle to capture RUSSIAN satellites and bring them back for analysis.

In the end, the US military realised that the capability to do this was actually very limited and fraught with danger. How many satellite retrieval missions were there in the entire programme - Two? Three?

[ninja-lewis]

Toaster said:

Spot on

What would also be interesting to find out is how the guidance system works for example Military accuracy GPS but also what about near landing is it just GPS or is RF positioning involved for the final approach. if you think about the nuances of the final position on Space X on the barge RF positioning would have quite an advantage for pin point landing on any craft.

Apparently one of the changes Blue Ocean made between the first and second launch was to reprogram the software away from doing a precise centre of the pad landing and to accepting a good enough position once over the pad. Made for a more stable landing compared to the aggressive last minute manoeuvring to land on the absolute centre.

Of course, it's easier to do that with a smaller rocket and a larger, stable pad on land versus landing a Falcon 9 on a small barge.

[Toaster]

Leithen said:

His name was Stephen Merrett. I worked for him. He was a risk taker.

Indeed he was and at the time I believe it was seen as a good deal Its a shame they are not still trading

[Eric Mc]

ash73 said:

Eric Mc said:

How many satellite retrieval missions were there in the entire programme - Two? Three?

You mean how many in the public domain?

It would be an extremely difficult type of mission to hide. There were 135 Shuttle flights. Even though a small number of these were military and had secret aspects to them that are still classified, the rendezvous with and retrieval of a satellite in the orbits that the Shuttle was capable of achieving meant that any such missions would be blindingly obvious.

[Mojocvh]

Toaster said:

ash73 said:

I think they are both awesome, the landing is the impressive bit.

Spot on

What would also be interesting to find out is how the guidance system works for example Military accuracy GPS but also what about near landing is it just GPS or is RF positioning involved for the final approach. if you think about the nuances of the final position on Space X on the barge RF positioning would have quite an advantage for pin point landing on any craft.

What is interesting was the difference in accuracy between the land and barge landings....

[Beati Dogu]

ninja-lewis said:

Toaster said:

Spot on

What would also be interesting to find out is how the guidance system works for example Military accuracy GPS but also what about near landing is it just GPS or is RF positioning involved for the final approach. if you think about the nuances of the final position on Space X on the barge RF positioning would have quite an advantage for pin point landing on any craft.

Apparently one of the changes Blue Ocean made between the first and second launch was to reprogram the software away from doing a precise centre of the pad landing and to accepting a good enough position once over the pad. Made for a more stable landing compared to the aggressive last minute manoeuvring to land on the absolute centre.

Of course, it's easier to do that with a smaller rocket and a larger, stable pad on land versus landing a Falcon 9 on a small barge.

SpaceX use a crew of specially trained pigeons to land their rockets. They should really call it the Pigeon 9.

https://www.youtube.com/watch?v=uOkpvEZ-p2k

The first one crashed due to insufficient peanuts.



The accuracy of civilian GPS has been the same as military GPS since they disabled Selective Availability in 2000. That said, they probably use some sort of augmentation like WAAS.

https://en.wikipedia.org/wiki/Wide_Area_Augmentati...

The New Shepard has one engine it uses for everything. The Falcon 9 uses 3 of its 9 engines to slow itself down and bring it back. Only the centre engine is used to actually land, but to control it they have the fold out fins, side thrusters and of course the engine gimble mounts to steer that around.

[Toaster]

ash73 said:

You mean how many in the public domain?

you may recall this sinister capture of a Russian space craft http://www.fantastic-plastic.com/SPECTREBirdOne-Pa...

[Toaster]

Beati Dogu said:

SpaceX use a crew of specially trained pigeons to land their rockets. They should really call it the Pigeon 9.

https://www.youtube.com/watch?v=uOkpvEZ-p2k

The first one crashed due to insufficient peanuts.



The accuracy of civilian GPS has been the same as military GPS since they disabled Selective Availability in 2000. That said, they probably use some sort of augmentation like WAAS.

https://en.wikipedia.org/wiki/Wide_Area_Augmentati...

The New Shepard has one engine it uses for everything. The Falcon 9 uses 3 of its 9 engines to slow itself down and bring it back. Only the centre engine is used to actually land, but to control it they have the fold out fins, side thrusters and of course the engine gimble mounts to steer that around.

Looks like they have the peanuts sorted I had not heard of WAAS but would seem sensible to include a system such as that, and I think the complexities of the Falcon 9 control system is where modern software meets hardware control. Wont be long before all the manufacturers catch up. not sure if you had seen it but earlier I had posted some links where small unknown companies had demonstrated hovering rockets which were controllable from lift off manoeuvre around and area and then land back to the launch spot so this technology has been years in development and testing.

I know some will say ah but Musk's is bigger but then its not always about size

[Scuffers]

unlikely they use WAAS, it's simply not accurate enough (or fast enough).

more likely they use a FOG based inertial navigation system with some form of external verification.

[Mojocvh]

Toaster said:

Scuffers said:

nobody is suggesting otherwise, the simple facts are that SpaceX is the first to actually work on getting a commercially viable rocket system to achieve it.

Nasa spent billions going down the wrong route with the shuttle programme, they could have done far more with less money just keeping the Saturn 5 programme, you know, the rocket that 40+ years ago could put more mass into orbit than anything before or since, (Skylab anyone?)

I was refering to this statement 'Obviously Musk has really got the establishment rattled with his forward leaning ideals.' clearly Mr Musk has the financial clout to make it happen, along with the technology that has been developed in other industries but I would argue he is just utilising ideals that were outlined long ago.

You do understand what the big picture actually is?