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  • 2 weeks later...
Posted (edited)

Article on feasibility of different orbital launch systems. https://www.realclearscience.com/blog/2018/07/14/will_we_ever_stop_using_rockets_to_get_to_space.html

 

I've always wondered why lighter-that-air lift systems haven't gotten more thought in designing orbital launch systems? The USAF (then) and the DHS (now) run a program called TARS (Tethered Aerostat Radar System) that uses semi rigid aerostats to lift a 20k kg payload. The max the Falcon 9 can lift is 54k kg. take away the fuel requirements to generate sufficient lift from sea level and it should be in the ballpark. Just a thought.

 

Edit: The TARS payload is actually 1k kg. The aerostats have a max theoretical lift of 5k kg. Multiple aerostats can be used. Again, theoretically. TARS does not need to do it but it can be done.

Edited by Guard Dog
  • Like 2

"While it is true you learn with age, the down side is what you often learn is what a damn fool you were before"

Thomas Sowell

Posted

I've always wondered why lighter-that-air lift systems haven't gotten more thought in designing orbital launch systems? The USAF (then) and the DHS (now) run a program called TARS (Tethered Aerostat Radar System) that uses semi rigid aerostats to lift a 20k kg payload. The max the Falcon 9 can lift is 54k kg. take away the fuel requirements to generate sufficient lift from sea level and it should be in the ballpark. Just a thought.

 

Edit: The TARS payload is actually 1k kg. The aerostats have a max theoretical lift of 5k kg. Multiple aerostats can be used. Again, theoretically. TARS does not need to do it but it can be done.

Reaching space is far more about total speed then starting height.

While there are some airborne launch systems it's just rarely worth the effort.

Posted (edited)

Article on feasibility of different orbital launch systems. https://www.realclearscience.com/blog/2018/07/14/will_we_ever_stop_using_rockets_to_get_to_space.html

 

I've always wondered why lighter-that-air lift systems haven't gotten more thought in designing orbital launch systems? The USAF (then) and the DHS (now) run a program called TARS (Tethered Aerostat Radar System) that uses semi rigid aerostats to lift a 20k kg payload. The max the Falcon 9 can lift is 54k kg. take away the fuel requirements to generate sufficient lift from sea level and it should be in the ballpark. Just a thought.

 

Edit: The TARS payload is actually 1k kg. The aerostats have a max theoretical lift of 5k kg. Multiple aerostats can be used. Again, theoretically. TARS does not need to do it but it can be done.

 

Edited by Chilloutman

I'm the enemy, 'cause I like to think, I like to read. I'm into freedom of speech, and freedom of choice. I'm the kinda guy that likes to sit in a greasy spoon and wonder, "Gee, should I have the T-bone steak or the jumbo rack of barbecue ribs with the side-order of gravy fries?" I want high cholesterol! I wanna eat bacon, and butter, and buckets of cheese, okay?! I wanna smoke a Cuban cigar the size of Cincinnati in the non-smoking section! I wanna run naked through the street, with green Jell-O all over my body, reading Playboy magazine. Why? Because I suddenly may feel the need to, okay, pal? I've SEEN the future. Do you know what it is? It's a 47-year-old virgin sitting around in his beige pajamas, drinking a banana-broccoli shake, singing "I'm an Oscar Meyer Wiene"

Posted

 

I've always wondered why lighter-that-air lift systems haven't gotten more thought in designing orbital launch systems? The USAF (then) and the DHS (now) run a program called TARS (Tethered Aerostat Radar System) that uses semi rigid aerostats to lift a 20k kg payload. The max the Falcon 9 can lift is 54k kg. take away the fuel requirements to generate sufficient lift from sea level and it should be in the ballpark. Just a thought.

 

Edit: The TARS payload is actually 1k kg. The aerostats have a max theoretical lift of 5k kg. Multiple aerostats can be used. Again, theoretically. TARS does not need to do it but it can be done.

Reaching space is far more about total speed then starting height.

While there are some airborne launch systems it's just rarely worth the effort.

 

Actually you are incorrect. Escape velocity is inversely proportional to the r (distance from center of mass). Get farther away from the center of mass and you need less V. You also need less energy to overcome air resistance if you begin thrust higher in the atmosphere. Less V means less fuel. So the idea would be to use lighter than air lift to elevate and orbital vehicle to an optimum altitude and then begin thrusting from there.

 

The math just may not work. Otherwise I'm sure this would have been tried. But, in theory...

"While it is true you learn with age, the down side is what you often learn is what a damn fool you were before"

Thomas Sowell

Posted

 

 

I've always wondered why lighter-that-air lift systems haven't gotten more thought in designing orbital launch systems? The USAF (then) and the DHS (now) run a program called TARS (Tethered Aerostat Radar System) that uses semi rigid aerostats to lift a 20k kg payload. The max the Falcon 9 can lift is 54k kg. take away the fuel requirements to generate sufficient lift from sea level and it should be in the ballpark. Just a thought.

 

Edit: The TARS payload is actually 1k kg. The aerostats have a max theoretical lift of 5k kg. Multiple aerostats can be used. Again, theoretically. TARS does not need to do it but it can be done.

Reaching space is far more about total speed then starting height.

While there are some airborne launch systems it's just rarely worth the effort.

 

Actually you are incorrect. Escape velocity is inversely proportional to the r (distance from center of mass). Get farther away from the center of mass and you need less V. You also need less energy to overcome air resistance if you begin thrust higher in the atmosphere. Less V means less fuel. So the idea would be to use lighter than air lift to elevate and orbital vehicle to an optimum altitude and then begin thrusting from there.

 

The math just may not work. Otherwise I'm sure this would have been tried. But, in theory...

 

But air launches have been done with Pegasus.

And balloon launches are being developed.

But it's clearly for minor payloads, they can't scale the same way that rockets can.

  • 2 weeks later...
Posted

Interesting study on the correlation of sleep deprivation and loneliness. https://www.telegraph.co.uk/science/2018/08/14/sleep-deprivation-fuels-loneliness-tired-people-socially-repellent/
 

I've always thought of this a s a chicken and egg argument. Are you lonely because you are tired or are not sleeping because you are lonely? For my part after two failed marriages whenever I feel lonely brooding over past wrongs usually alleviates it. 

"While it is true you learn with age, the down side is what you often learn is what a damn fool you were before"

Thomas Sowell

Posted (edited)

https://www.reuters.com/article/us-gsk-hiv/long-acting-injection-boosts-hopes-for-gsks-hiv-business-idUSKBN1L00L2

 

 

Guys this is a  great development, Glaxo has tested a new HIV treatment where you only need two  injections a month as opposed to taking pills every day !!!

Edited by BruceVC

"Abashed the devil stood and felt how awful goodness is and saw Virtue in her shape how lovely: and pined his loss”

John Milton 

"We don't stop playing because we grow old; we grow old because we stop playing.” -  George Bernard Shaw

"What counts in life is not the mere fact that we have lived. It is what difference we have made to the lives of others that will determine the significance of the life we lead" - Nelson Mandela

 

 

  • 2 weeks later...
Posted

Article on feasibility of different orbital launch systems. https://www.realclearscience.com/blog/2018/07/14/will_we_ever_stop_using_rockets_to_get_to_space.html

 

I've always wondered why lighter-that-air lift systems haven't gotten more thought in designing orbital launch systems? The USAF (then) and the DHS (now) run a program called TARS (Tethered Aerostat Radar System) that uses semi rigid aerostats to lift a 20k kg payload. The max the Falcon 9 can lift is 54k kg. take away the fuel requirements to generate sufficient lift from sea level and it should be in the ballpark. Just a thought.

 

Edit: The TARS payload is actually 1k kg. The aerostats have a max theoretical lift of 5k kg. Multiple aerostats can be used. Again, theoretically. TARS does not need to do it but it can be done.

 

My favorite is the Orbital Ring. But it's far from feasible... :p

 

 

This channel has very good videos for most launch systems. I highly recommend checking it.

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