SpaceX Grasshopper Makes Another Jump

The SpaceX Grasshopper makes another small leap in the pursuit of first stage reusability in this video tweeted by Elon Musk on Saturday, November 3.  While there are a number of efforts to develop reusable launch vehicles underway, most, like Blue Origin,  are taking an incremental, scaled approach to the issue starting with subscale, suborbital systems and working their way up.  SpaceX by contrast, is using its proven Falcon 9 first stage as a starting point.  Both are credible approaches, and it should prove interesting to see which is ultimately successful. Hopefully it will be all of the above.

The Grasshopper is just beginning an initial  three phase testing program designed to culminate in ascent, hover, and landing flights reaching a peak of 11,500 feet. Each will be powered by a single, gimballed Merlin 1D engine mounted on the modified F9 first stage.   With an avowed plan to develop a powered descent and landing capability for the next generation Dragon spacecraft as well, success in one area may inform the other. Considering the impressive in-space control capability the current Dragon has already demonstrated on two flights to the International Space Station, it seems a fair bet that the company will ultimately succeed on both efforts.

The real challenge will come in applying the experience gained with Grasshopper to an actual orbital launch,  and with re-asserting control of a first stage in ballistic flight after stage separation. Elon Musk has previously suggested that the best solution may lie in conducting stage separation at a lower velocity, somewhere around Mach 6 as opposed to Mach 10 in the current flight profile.  The result would be a tradeoff between leaving enough remaining fuel in the first stage for a powered descent, and a corresponding decrease in payload to orbit delivered by the second stage of roughly 40%. If the reduction in payload capacity appears problematic, two points bear consideration. First, a growing trend towards electrical propulsion for commercial satellites may align neatly with the arrival of a launch system geared for extremely low cost LEO delivery of GSO bound satellites. Second,  although it is obviously premature to begin projecting launch prices for a system which is still years from becoming reality, the $54 million launch cost of the current fully expendable Falcon 9 suggests a breakeven point somewhere between three and five launches between the two systems.

Although success is likely a long way off and there may be an uncomfortable number of bad days and bad press  in-between, it is encouraging that companies such as SpaceX, Blue Origin,  Masten, and Armadillo, are undertaking the effort. It is also equally noteworthy to consider the conspicuous absence of other, much larger companies which are nowhere to be found when it comes to making “expendable” a dirty word.

Moreover, because corporations are not necessarily tasked with providing leadership, whereas government  is,  it is also profoundly disturbing  that despite the obvious benefits of achieving commercially viable  first stage reusability, NASA, at the direction of Congress, is paying scant attention to the issue even as it plows billions of dollars into the SLS super heavy booster. Given the stunning inefficiency imbedded into a plan which calls for the development of new strap-on boosters,  and new second stage engines after ten years and only two questionable flights, is it too much to suggest that perhaps we could do at least a little better?

One place to start might be with an expansion of NASA’s very modest Flight Opportunities Program , which currently helps researchers secure flight opportunities on parabolic airplanes, high altitude balloons, and more significantly, commercial reusable suborbital vehicles.  Another, more direct route would be a COTS like program which rewarded companies for meeting several key milestones along the path to first stage reusability, particularly in areas which offer the greatest obstacles and in which we have the least experience.

Whatever the outcome of the U.S. Presidential election, it is clearly time for a re-examination of priorities which at least takes into account the progress being made on the one problem which is the primary impediment to expanding both space exploration and commerce.

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