SpaceX Tuesday...
Discussion
I like this shot of the aquatic Falcon 9 being towed past the waiting USS Indiana, a nuclear attack submarine.
They've lifted out of the sea now and it's resting on supports by the dockside.
More pics:
https://twitter.com/ken_kremer
They've lifted out of the sea now and it's resting on supports by the dockside.
More pics:
https://twitter.com/ken_kremer
When the booster is heading back to earth, you see the grill-like fins in the footage from the camera attached to it. From the pics above, the fins seem to be a the top of the booster. Yet when you look at the onboard footage, they seem to be at the bottom.
Are they at the top or the bottom (near the main engines)?
Ta.
Are they at the top or the bottom (near the main engines)?
Ta.
funkyrobot said:
When the booster is heading back to earth, you see the grill-like fins in the footage from the camera attached to it. From the pics above, the fins seem to be a the top of the booster. Yet when you look at the onboard footage, they seem to be at the bottom.
Are they at the top or the bottom (near the main engines)?
Ta.
They are at the top. Are they at the top or the bottom (near the main engines)?
Ta.
On board footage is from the very top, perspective and a wide angle lens makes the fins seem far away. In reality there's 40m of booster further on.
RobDickinson said:
funkyrobot said:
When the booster is heading back to earth, you see the grill-like fins in the footage from the camera attached to it. From the pics above, the fins seem to be a the top of the booster. Yet when you look at the onboard footage, they seem to be at the bottom.
Are they at the top or the bottom (near the main engines)?
Ta.
They are at the top. Are they at the top or the bottom (near the main engines)?
Ta.
On board footage is from the very top, perspective and a wide angle lens makes the fins seem far away. In reality there's 40m of booster further on.
Out of interest, is there a published cost/benefit analysis comparing the disposable and reusable launch vehicles? How does the cost of building something more complex and heavier, the extra fuel to lift it and land it (and therefore potential payload lost) and the cost of recovery and refurbishment compare to a single use vehicle? Presumably it must have been done. Intuitively, one would think it must be cheaper to re-use, especially with something so expensive to build. To use a trivial example, I read somewhere it's cheaper to make a new glass bottle than it is to collect, clean and re-use an old one. But that may be more to do with consumers not liking scratched bottles. Anyone remember the almost opaque beer bottles in days gone by when they were reused multiple times?
1st stage is worth around $40mil from SpaceX, already dirt cheap comparatively.
Those titanium grid fins are expensive, a few million at a guess, the legs and hydraulics etc will cost but you get to sell $400m of booster for the cost of $50mil
Fuel is peanuts.
The F9 has an abundance of performance for most launches, and if its really big they throw it away (using an old booster ideally) or use a heavy.
The next spacex launch is a disposable launch (no landing) so no feet or grid fins.
Those titanium grid fins are expensive, a few million at a guess, the legs and hydraulics etc will cost but you get to sell $400m of booster for the cost of $50mil
Fuel is peanuts.
The F9 has an abundance of performance for most launches, and if its really big they throw it away (using an old booster ideally) or use a heavy.
The next spacex launch is a disposable launch (no landing) so no feet or grid fins.
Unsure of the figures but to work out the cost effectiveness of reuse you just need to look at the price to orbit per kilo with SpaceX vs other launch organisations. They’ve hugely reduced the cost of putting stuff into space.
Edit: here you go
Edit: here you go
Edited by Polite M135 driver on Sunday 9th December 10:26
How much does a launcher cost? I'd imagine it would be cheaper to engineer something designed to be used once rather than say ten times. I'm hoping we reach a point when launches are boringly safe and routine in my lifetime. Sadly I expect the weaponization of space will be a driver. The ability to knock out another country's comms or GPS satellites with ease would be a game-changer in the power game. Whatever treaties are signed to prevent this, you can be sure everyone will cheat. It's a sad indictment of the human condition that the greatest periods of technological progress seem to coincide with wars or superpower rivalries.
rovermorris999 said:
How much does a launcher cost? I'd imagine it would be cheaper to engineer something designed to be used once rather than say ten times. I'm hoping we reach a point when launches are boringly safe and routine in my lifetime. ...
It's relative, your development costs are proportional to your operating goals and market costs.A lot of this stems from a combination of the Moon race and Balistic weapons development, the main benefit of only developing a non-resuable rocket is time to market and missile systems generally only being used once (capitalism at it's finest).
The Military investment stops once they have what they need.
As the aim was to get to The Moon before the other competitors, then the main goal was time.
This was the original aim of The Shuttle, but this was compromised by political interference from the Military Industrial complex.
Making space access affordable requires someone to "upset the apple cart" as the yanks like to say, making reusable spacecraft is an economic and engineering problem not a scientific one.
A fully re-usable spacecraft would offer huge economic benefits to those with the will to develop them, the challenge is doing it without a massive budget and before the next person does it.
annodomini2 said:
This was the original aim of The Shuttle, but this was compromised by political interference from the Military Industrial complex.
The Shuttle was a political project from day 1. It would not even have been conceived if it hadn't been for political pressure on NASA to dispense with "wasteful" and "costly" single use boosters.Gassing Station | Science! | Top of Page | What's New | My Stuff