Research in Engineering and Aviation

Cheaper by the Dozen: The Avalanche of Rideshares in the 21st Century

March 2013

Author(s):  Swartwout, M.A. 

“Cheaper by the Dozen: The Avalanche of Rideshares in the 21st Century,” 2013 IEEE Aerospace Conference, Big Sky, MT, 4 March 2013, paper 2472.


In the previous two conferences, we presented a statistics-based history of rideshares, first with the 300 rideshares launched from 1990-2010, then with the 600 rideshares launched in the first 54 years of spaceflight. We showed that there have been several waves of rideshares, each with their own particular characteristics: the avalanche of US military rideshares of the 60s (acting as calibration targets, environmental sensors and performing other space-qualification tasks); the slow-build of commercial rideshares starting with the Ariane ASAP in the early 80s, and now a bifurcation into 100-kg ESPA-class spacecraft and a second, larger avalanche of CubeSats.

Avalanches? Yes! The long-promised increase in rideshares has come; nearly 40 rideshares are manifested to launch in 2012 and at least 100 in 2013 – more than double any previous year, ever. Furthermore, 2013 will be the fifth consecutive year with more than 20 rideshares, the first time this has happened since 1965-1969. If anything, 2014 looks to set new records.

What should we make of these numbers? Are they all CubeSats? (Answer: yes, mostly.) Who is flying them? (Answer: the U.S. Department of Defense, with NASA close behind.) In this paper, we will revisit our analysis of the past two years in the light of the new data, revising our predictions on bifurcation and the availability of CubeSat rideshares. We will expand our study to look at the military, civil and university sectors. We will offer foolish predictions on what to expect in 2013 and 2014. (Hint: more CubeSats, maybe some ESPAs.)