Reusable Upper Stage OTV


The next major step is the Orbit Transfer Vehicle or Space Tug, to ferry satellites from LEO to GEO. In-space refueling enables OTVs to carry out many missions. OTVs render the expensive cryogenic third-stage of many GEO launchers, superfluous. A much smaller orbit correction engine and a supply of fuel is all that is needed, with the OTV performing the LEO-GEO delivery. In the short term, this would hurt the manufacture of third-stage engines, but in the longer term, the demand for OTVs should more than replace the lost business. Here the emphasis is on the engine rather than the fuel. The idea is to provide high-thrust upper-stage engines that will take satellites from LEO to GEO, and then leave them there with only low-thrust, high Isp orbit correction engines for the rest of their lifetime (with the possibility of reboost/refuel). The engine then comes down and is reused. The number of engine firings is limited by material degradation. The impact on customer cost is the drastic reduction in launch cost per unit payload delivered to LEO, since the mass of the upper stage engine, the boost fuel, and the risk associated with first-time operation of a new cryogenic engine, are all avoided. The fuel is delivered in LEO, at the cost negotiated between the RUS and the tanker OTV, and may range from the low costs expected if the fuel comes from expendable boosters, to the higher costs of earth-delivered fuel, which comes in packages sent up on low-cost, high-risk launches rather than the expensive satellite launch vehicle.


Mass-10000 kg

Isp of 460 seconds[i].

Revenue per boost - $25M


Development Cost - $100M

Cost per 3rd stage[ii]: $20M

Maintenance - $10M

Operation - $10M per boost + $5M/yr for flight control services.

Lifetime: 50 burns.



Launch Costs determined by $26,000/kg to GEO (source:  Futron[iii] , $13,000/kg to LEO)

Revenue starts decreasing by 5%, 20 years after start of company.





[i] Leisman, G. A., Joslyn, T. B., Siegenthaler, K. E.  "CEV Architectures: Cost Effective Transportation System to the Moon and Mars". 1 September 2004. Architectures Cost Effective Transportation System to the Moon and Mars - Joslyn.doc Viewed 22 August 2006.

[ii]Zak, A.,  Making Progress? Russia's Financial Problems Could Impact ISS Occupation. 25 April 2002.  22 August 2006. <>.

[iii]Futron Corporation. Space Transportation Costs: Trends in Price Per Pound to Orbit 1990-2000. 6 September

2002. 22 August 2006.  Viewed Aug. 23, 2006.