Rockets for satellite launches remain the most important cost item of the launch process of any commercial satellite project, given the single use nature of the rocket. Thus, commercial space launch companies such as SpaceX and Blue Origin have endeavoured to develop reusable rocket systems for reducing the cost of commercial satellite launches, and helping realize a future of low cost space travel. Specifically, both companies attempted, and succeeded in reusing the first stage of a multi-stage rocket; thus, paving the way for a future where more companies and nations would be able to afford their communication or remote sensing satellites.
Specifically, SpaceX succeeded in landing, retrofitting and reusing a first stage rocket subsequently successfully deployed for another commercial satellite launch, which demonstrates the utility of the concept in allowing a retrofitted first stage rocket be flown again on another mission. While the concept is attractive for reducing the cost of commercial satellite launches, many questions remain.
One of the most important lies in the safety of the reused first stage rocket, as well as the cost of retrofitting a used rocket. Specifically, given the cost involved in building, testing and certifying a satellite for communications or remote sensing, the launch customer would naturally demand a certified rocket able to reliably ferry the satellite into orbit. Thus, the cost of retrieving a used rocket, retrofitting it for replacing worn out or expendable parts, and re-certifying the rocket for flight worthiness prior to the next launch is likely to be immense, although no figures are released by SpaceX and Blue Origin on the cost of retrofitting a used first stage rocket and certifying it for flight. More importantly, both companies did not release figures on how much savings would a reused rocket bring to the commercial space launch business.
Next, given the understandable risk of malfunctions arising from a retrofitted first stage rocket, the question of whether it should be used as part of a rocket system for human space flight remain controversial, and is one which require deep considerations from scientists, engineers, and policymakers. While one can argue that there are inherent risks of failure even in new rockets, the same risk is understandably higher in reused first stage rockets.
Collectively, while commercial space launch companies have demonstrated the feasibility of using a reused first stage rocket for subsequent launch of a commercial satellite, the verdict is still out on whether the reuse of a first stage rocket helps reduce launch expense for the satellite owner. This is important given that significant expense must have been expended in retrofitting a used first stage rocket to ensure safety and reliability for subsequent launch, where understandably, many parts, worn out or not, would need to be replaced. Hence, the allure of lower cost of launching a commercial satellite using reused first stage rockets would need to be checked with hard headed economics and deep considerations concerning the trade-offs between launch and satellite safety with potential cost savings. Certainly, potential use of reused first stage rocket for human space flight is highly debatable concerning the risk of failure of reused first stage rockets is inherently higher than a new one.
Category: space exploration, mechanical engineering, materials, materials engineering,
Tags: reused rockets, first stage rocket, commercial space launch, human space flight, retrofitted rocket, certification, safety, reliability,