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I've been super impressed with how efficient SpaceX is in getting launches into orbit. I did a visual comparison to the Space Shuttle program. It looks like S

I've been super impressed with how efficient SpaceX is in getting launches into orbit. I did a visual comparison to the Space Shuttle program. It looks like SpaceX will overtake the Space Shuttle launch efficiency by the end of the year. http://snag.gy/wUTD7.jpg http://snag.gy/wUTD7.jpg sources: http://en.wikipedia.org/wiki/List_of_space_shuttle_missions http://en.wikipedia.org/wiki/List_of_space_shuttle_missions http://en.wikipedia.org/wiki/List_of_Falcon_9_launches http://en.wikipedia.org/wiki/List_of_Falcon_9_launches

bellerocky 12y ago
The space shuttle launches are manned missions. I don't think it's a fair comparison.
- larrydag 12y ago
  good point. I was considering the comparison as resupply missions and (future) re-usability of the vehicle.
  - Shivetya 12y ago
    can you compare these to the Russian unmanned supply runs to the ISS?
tnorthcutt 12y ago
That graph might be a little more intuitive if you swapped the axes, FWIW.
- hughes 12y ago
  Definitely. Also choose colours that aren't almost identical.
  - Dylan16807 12y ago
    The blue and black don't look very close to me, and they're pretty color-blind safe. Odd.
    - PeterWhittaker 12y ago
      I cannot tell them apart, other than length. Be nice to have one solid, the other dashed or dotted.
    - m_mueller 12y ago
      Don't underestimate the damage of bad screens, bad screen settings and people blaming the source rather than their setup.
      - jfoster 12y ago
        Even just laptop screen brightness or glare can play a huge role here. I know it's offtopic, but if anyone is aware of a guide or methodology for picking colors that will be less susceptible to this problem, I would love to see it.
        sitkack 12y ago
        Convert to grayscale.
        chmullig 12y ago
        colorbrewer
        Someone 12y ago
        'Cheat' and use something else to differentiatie between the two, in addition to color (line thickness, line dash, markers) You probably should always do that, as you won't know where your chart will be used (printed in black and white, very lossily converted to JPEG, whatever)
      - rplnt 12y ago
        It's all right to blame the source. Imagine half a population having grayscale screens. Would you pick colors that map to the same shade of gray? I guess not, so why would you pick colors and thickness that can be mistaken on so many setups? In this case it doesn't matter, as it's obvious which line is which.
- ghshephard 12y ago
  It would be a lot more intuitive. Even knowing exactly what was being described and how - It still is difficult for me to understand a graph in which Time is on the Y-axis. I considered for a few moment that I was actually being trolled with that graph.
pothibo 12y ago
Telecoms and the market for satellites has only recently boomed. You cannot compare the two programs in such a way.
- ceejayoz 12y ago
  The limiting factor of the Shuttle wasn't low demand for its services, I don't think.
  - Retric 12y ago
    Demand was ~1/10 of projected demand which dramatically increased costs not only by increasing overhead by also by extending vehicle lifespans well beyond what they where designed for. Put another way, scrapping a shuttle mission saved less than 90 million. PS: It was also horribly compromised based on Airforce requirements yet never flew a single Airforce mission.
    - nickff 12y ago
      I am not sure what the rated vehicle lifespans were at the time of building, but the design life was 100 missions per shuttle, and the most-flown shuttle (Discovery) only flew 39.
      - Retric 12y ago
        The initial assumption was 40 missions a year. Based on the estimated risks you might get 100 missions from a shuttle on average. So 5 orbitors * 100 / 40 = 12.5 years or ~ 10 years with an early loss. They where in service for 30 years and averaged 4.5 missions per year. For comparison compare the matence cycle a low mileage 0 to 10 year old car vs a low mileage 15 to 30 year old car.
        nickff 12y ago
        I've heard this reasoning before (from NASA personnel), but I have never seen the reasoning behind it. Many of the design life requirements were impossible to meet to begin with, such as the 50-launch design life of the Space Shuttle main engines (because of the high chamber pressures, and problems with bearings). If you have some evidence of the veracity of this claim, I would be very interested to read it.
sitkack 12y ago
Are you taking into account inflation adjusted cost?
rsynnott 12y ago
Shuttle was alway fairly low-frequency, far below its design goals, so possibly not a great comparison. Here's 2014 in space launches: http://en.wikipedia.org/wiki/2014_in_spaceflight http://en.wikipedia.org/wiki/2014_in_spaceflight At peak, in the 70s, there were about 140 launches per year.
smackfu 12y ago
An expendable vehicle should be inherently more efficient in launching frequency than a reusable one. The reusable one is fundamentally limited by the number of reusable vehicles you have on hand and the time it takes to turn each around. The expendable one is only limited by the speed of your manufacturing. So, since SpaceX is moving to a reusable vehicle, this graph could easily change slope in the future.

bellerocky 12y ago

The space shuttle launches are manned missions. I don't think it's a fair comparison.

larrydag 12y ago
good point. I was considering the comparison as resupply missions and (future) re-usability of the vehicle.
- Shivetya 12y ago
  can you compare these to the Russian unmanned supply runs to the ISS?

tnorthcutt 12y ago

That graph might be a little more intuitive if you swapped the axes, FWIW.

hughes 12y ago
Definitely. Also choose colours that aren't almost identical.
- Dylan16807 12y ago
  The blue and black don't look very close to me, and they're pretty color-blind safe. Odd.
  - PeterWhittaker 12y ago
    I cannot tell them apart, other than length. Be nice to have one solid, the other dashed or dotted.
  - m_mueller 12y ago
    Don't underestimate the damage of bad screens, bad screen settings and people blaming the source rather than their setup.
    - jfoster 12y ago
      Even just laptop screen brightness or glare can play a huge role here. I know it's offtopic, but if anyone is aware of a guide or methodology for picking colors that will be less susceptible to this problem, I would love to see it.
      - sitkack 12y ago
        Convert to grayscale.
      - chmullig 12y ago
        colorbrewer
      - Someone 12y ago
        'Cheat' and use something else to differentiatie between the two, in addition to color (line thickness, line dash, markers) You probably should always do that, as you won't know where your chart will be used (printed in black and white, very lossily converted to JPEG, whatever)
    - rplnt 12y ago
      It's all right to blame the source. Imagine half a population having grayscale screens. Would you pick colors that map to the same shade of gray? I guess not, so why would you pick colors and thickness that can be mistaken on so many setups? In this case it doesn't matter, as it's obvious which line is which.
ghshephard 12y ago
It would be a lot more intuitive. Even knowing exactly what was being described and how - It still is difficult for me to understand a graph in which Time is on the Y-axis. I considered for a few moment that I was actually being trolled with that graph.

pothibo 12y ago

Telecoms and the market for satellites has only recently boomed. You cannot compare the two programs in such a way.

ceejayoz 12y ago
The limiting factor of the Shuttle wasn't low demand for its services, I don't think.
- Retric 12y ago
  Demand was ~1/10 of projected demand which dramatically increased costs not only by increasing overhead by also by extending vehicle lifespans well beyond what they where designed for. Put another way, scrapping a shuttle mission saved less than 90 million. PS: It was also horribly compromised based on Airforce requirements yet never flew a single Airforce mission.
  - nickff 12y ago
    I am not sure what the rated vehicle lifespans were at the time of building, but the design life was 100 missions per shuttle, and the most-flown shuttle (Discovery) only flew 39.
    - Retric 12y ago
      The initial assumption was 40 missions a year. Based on the estimated risks you might get 100 missions from a shuttle on average. So 5 orbitors * 100 / 40 = 12.5 years or ~ 10 years with an early loss. They where in service for 30 years and averaged 4.5 missions per year. For comparison compare the matence cycle a low mileage 0 to 10 year old car vs a low mileage 15 to 30 year old car.
      - nickff 12y ago
        I've heard this reasoning before (from NASA personnel), but I have never seen the reasoning behind it. Many of the design life requirements were impossible to meet to begin with, such as the 50-launch design life of the Space Shuttle main engines (because of the high chamber pressures, and problems with bearings). If you have some evidence of the veracity of this claim, I would be very interested to read it.

sitkack 12y ago

Are you taking into account inflation adjusted cost?

rsynnott 12y ago

Shuttle was alway fairly low-frequency, far below its design goals, so possibly not a great comparison. Here's 2014 in space launches: http://en.wikipedia.org/wiki/2014_in_spaceflight http://en.wikipedia.org/wiki/2014_in_spaceflight At peak, in the 70s, there were about 140 launches per year.

smackfu 12y ago

An expendable vehicle should be inherently more efficient in launching frequency than a reusable one. The reusable one is fundamentally limited by the number of reusable vehicles you have on hand and the time it takes to turn each around. The expendable one is only limited by the speed of your manufacturing. So, since SpaceX is moving to a reusable vehicle, this graph could easily change slope in the future.