Reusable rocket gone to space for the second time

Quote from: MaNaeSWolf on January 24, 2016, 10:33:41 AM

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Rocket thrust providing brake force? Well, the fuel (liquid oxygene and liquid hydrogene) must be carried up to 100 000 m altitude and I wonder what weight it has. 

You have this insistence that fuel can not be carried with without it being used up. Your essentially saying that a car can not go to the shops and then back again because you only put enough fuel in for the trip there.

In a zero gravity field, e.g. vacuum space, you cannot carry the fuel with you to brake after the trip, because you need extra fuel to get that fuel off the ground to start with and you get too heavy.

It is slightly different in a strong gravity field, e.g. between ground and 100 000 m altitude on Earth. Just to get off the ground, you need plenty energy and then, suddenly you are at 100 000 m altitude and start to drop down again.

If you just ascend to 10 000 m altitude, there is no problem. You use external means to brake when dropping down, e.g. a parachute in fairly thick air.

But 100 000 m altitude! No external means are prossible. Air is 1000X too thin. There is no air to talk of.  And internal means? Fuel to fire a rocket engine! Do your calculations. Can you get it with you up to 100 000 m altitude to suffice to stop you coming back? I doubt it.

That's why you (allegedly) build sea ships and not rocket ships. 

When your goal is to build a rocket that can can go to space and then land back at the launch site, then you take the fuel requirements for the trip down into consideration from the start.

When your goal is to build a rocket that can can go to space and then land back at the launch site, then you take the fuel requirements for the trip down into consideration from the start.

Correct. So what is the empty mass of the Blueorigin New Horizon rocket, the amonts of fuel used to get to 100 000 m altitude and fuel used to brake on return and the payload/capsule?

I assume they only went to 10 000 m altitude and used the atmosphere for braking.

Quote from: markjo on January 24, 2016, 12:23:16 PM

When your goal is to build a rocket that can can go to space and then land back at the launch site, then you take the fuel requirements for the trip down into consideration from the start.

Correct. So what is the empty mass of the Blueorigin New Horizon rocket, the amonts of fuel used to get to 100 000 m altitude and fuel used to brake on return and the payload/capsule?

They don't say (and they really aren't obligated to).  However, they do say that they several types of fins for control and atmospheric braking.

Ring fin and wedge fins
As the rocket reenters the atmosphere, air flows through a ring at the top of the booster, passively moving the center of pressure to help control descent. Four wedge-shaped fins also deploy to further enhance aerodynamic stability.

Drag brakes
Descending at the speed of sound, the booster deploys eight large drag brakes, reducing the vehicle’s speed by half.

Aft fins
Fins near the base of the booster pivot to stabilize the vehicle during ascent and steer it back to the landing pad on descent. Hydraulic actuators provide enough force to drive these fins through air speeds up to Mach 4.

I assume they only went to 10 000 m altitude and used the atmosphere for braking.

Why would you assume that? 

Reusable rockets were available when I was a kid.
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Tappett, how were able to get hold of this top secret NASA video?

So why are all real rockets streamlined & with control surfaces?
You know; like the V2 for example?
There's a lot of atmosphere to be navigated at LOW altitude before your 'extremely high' altitudes are reached, you know?

But I thought, on the best authority, that the V2 was basically a fake and never reached more than 12 miles (or was that metres? - these units confuse me so much!).  Of course at only 12 miles the V2s external fins might be useful.
But a bit more seriously the V2 had both external fins and carbon fins in the exhaust stream.
Mind you you the rocket in this video spends much less of its time in high density air, so why waste the weight and complication of external fins that are useless at the low speeds just after lift-off when control is needed, and useless at very high altitude!

Sure "lot of atmosphere to be navigated at LOW altitude" - mind you gets pretty thin after even 10 km or so , how fast is it going by then?

Streamlining & control surfaces are generally needed for such conditions.

Yes, I fully understand.  Non streamlined rockets wouldn't look like the Flash Gordon ones in the comics where most of you info comes from - probably not!  I think even Flash Gordon might have been one up on Papa.  I must admit my education was sadly neglected, I never did study Flash Gordon!

Only fake rockets don't need to be streamlined or have stabilising fins... & your ridiculous Blue Origin is as fake as they get.
They're not even trying for realism any more...

No, I can see that, they don't look at all like Flash Gordon rockets any more - no like the good ole V2!

Quote from: MaNaeSWolf on January 24, 2016, 10:33:41 AM

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Rocket thrust providing brake force? Well, the fuel (liquid oxygene and liquid hydrogene) must be carried up to 100 000 m altitude and I wonder what weight it has. 

You have this insistence that fuel can not be carried with without it being used up. Your essentially saying that a car can not go to the shops and then back again because you only put enough fuel in for the trip there.

In a zero gravity field, e.g. vacuum space, you cannot carry the fuel with you to brake after the trip, because you need extra fuel to get that fuel off the ground to start with and you get too heavy.

Why would you think vacuum space has no gravity?  The Earth and moon are still very close by once you are up there.

It is slightly different in a strong gravity field, e.g. between ground and 100 000 m altitude on Earth. Just to get off the ground, you need plenty energy and then, suddenly you are at 100 000 m altitude and start to drop down again.

Suddenly?  Wait do you know how gravity works?

If you just ascend to 10 000 m altitude, there is no problem. You use external means to brake when dropping down, e.g. a parachute in fairly thick air.

But 100 000 m altitude! No external means are prossible. Air is 1000X too thin. There is no air to talk of.  And internal means? Fuel to fire a rocket engine! Do your calculations. Can you get it with you up to 100 000 m altitude to suffice to stop you coming back? I doubt it.

Well all the evidence and calculations contradict you, as you have been shown here and elsewhere many, many, many times...

So what did we see on the video? Probably a stunt starting at max 15 000 m altitude.

Why do you say 15,000m?

So why are all real rockets streamlined & with control surfaces?
You know; like the V2 for example?
There's a lot of atmosphere to be navigated at LOW altitude before your 'extremely high' altitudes are reached, you know?

Don't control surfaces need a certain amount of air flow in order to be effective?  How is the rocket supposed to be controlled before it gains enough speed for the control surfaces to become effective?

Quote from: Heiwa on January 24, 2016, 11:52:00 AM

Quote from: MaNaeSWolf on January 24, 2016, 10:33:41 AM

Quote

Rocket thrust providing brake force? Well, the fuel (liquid oxygene and liquid hydrogene) must be carried up to 100 000 m altitude and I wonder what weight it has. 

You have this insistence that fuel can not be carried with without it being used up. Your essentially saying that a car can not go to the shops and then back again because you only put enough fuel in for the trip there.

In a zero gravity field, e.g. vacuum space, you cannot carry the fuel with you to brake after the trip, because you need extra fuel to get that fuel off the ground to start with and you get too heavy.

Why would you think vacuum space has no gravity?  The Earth and moon are still very close by once you are up there.

In vacuum space away from the Sun, planets and moons gravity is virtually zero according my understanding. Why you would stop there is another question - there is nothing there.

On the other hand on a planet like Jupiter gravity is much bigger than on Earth and would probably compress you, if you tried to stop there. 

Most Americans believe space is like Earth minus air and that braking is just to push the pedal in the middle like a car.

Quote from: Rama Set on January 24, 2016, 08:12:35 PM

Quote from: Heiwa on January 24, 2016, 11:52:00 AM

Quote from: MaNaeSWolf on January 24, 2016, 10:33:41 AM

Quote

Rocket thrust providing brake force? Well, the fuel (liquid oxygene and liquid hydrogene) must be carried up to 100 000 m altitude and I wonder what weight it has. 

You have this insistence that fuel can not be carried with without it being used up. Your essentially saying that a car can not go to the shops and then back again because you only put enough fuel in for the trip there.

In a zero gravity field, e.g. vacuum space, you cannot carry the fuel with you to brake after the trip, because you need extra fuel to get that fuel off the ground to start with and you get too heavy.

Why would you think vacuum space has no gravity?  The Earth and moon are still very close by once you are up there.

In vacuum space away from the Sun, planets and moons gravity is virtually zero according my understanding. Why you would stop there is another question - there is nothing there.

Away from the Sun?  What are you talking about?  Humans have never been anywhere that could remotely be described as that.

On the other hand on a planet like Jupiter gravity is much bigger than on Earth and would probably compress you, if you tried to stop there. 

True but irrelevant.

Most Americans believe space is like Earth minus air and that braking is just to push the pedal in the middle like a car.

Most Americans do?  Oh, how do you know that?  Technically, it is not a complicated concept, it is just a question of logistics.

Gimballed rocket engines are useless without control surfaces; ideally both fore & aft, & slaved to the chosen thrust vectoring system.
You'd know this if you understood anything about either rocketry or aerodynamics.

mr expert in aerodynamics..... aerodynamic surface in the front part of the rocket would make it less stable, is the same principle of the canards wings of plane, they shift forward the center of aerodynamic forces, reducing stability.
they're great if u wanna enhance maneuverability, that's why they're found in fighter jest and air to air missile, not so much for stability, that's why airliners don't have them