What are re-usable space launchers?
In my last post, I talked about space launch vehicles and the different stages associated with them. These vehicles could, literally, launch the commercial age of space, but wide-spread access and space travel will not be possible unless space launches are made more feasible.
This is why one of the biggest technological endeavours of the new space age has been to work towards developing reusable space launchers . This would not only make space launches cheaper, but also enable more frequent launches as each launch would not require a new vehicle.
Traditionally, space launch vehicles fall into the sea or disintegrate post re-entry. The first step towards achieving reusability was to recover or land the launch vehicle when it returned to Earth. As we had discussed in the last post, every launch vehicle has multiple stages which progressively detach as the vehicles moves towards its final destination, with the first stage being in the heaviest and the most expensive. In 2015, SpaceX successfully landed the first stage of Falcon9, its space launch vehicle for lower earth orbits. In fact, it was estimated that the reuse of first-stage launchers could bring down the cost of launches by 30% — 40%. Rockets Labs has designed a space launcher which does not detach any stage of the rocket. Post reaching the desired altitude, the vehicle releases the payload and returns to the launch site.
But any module successfully recovered or landed cannot directly be reused for another launch. Given the tremendous air resistance and friction along with force that the space launchers experience, modules need to be checked and refurbished. For components recovered from the sea, salt deposits also need to be removed. Hence, before they are refurbished for launch, these modules must be checked for any defects, damage and debris that might impact or harm their next journey. This further increases the costs and timelines for reuse. Therefore, reducing the cost and time of refurbishment across the stages of launch vehicles, along with developing reusable launch vehicle designs has been the focus of research and development work across companies and startups .
With 17,000 small satellites estimated to be launched by 2030, the commercialisation of the space industry will ultimately depend on space launches becoming cheaper.
