SpaceX reconsiders Starship design

In a series of recent tweets, SpaceX CEO Elon Musk revealed that the company has redesigned its Starship, formerly known as the Big Falon Rocket (BFR). Musk indicated that the carbon fiber skin and some carbon fiber components of the vehicle are to be swapped out for stainless steel. Stainless steel weighs significantly more than carbon fiber, so the choice to change the material has become the topic of some debate.

While not many specific details were disclosed, Musk hinted that the reasoning behind the change in material seems to be out of concern for the extreme heat of re-entry. In a Dec. 24 tweet he stated, “Usable strength/weight of full hard stainless at cryo is slightly better than carbon fiber, room temp is worse, high temp is vastly better.”

While many spacecraft use ablative heat shields that burn away or disintegrate in a controlled manner during re-entry, such an approach would require repairs before reuse and SpaceX’s Starship is meant for quick turnaround and reuse. The redesign seems to be based on reflective heat shielding designed to withstand re-entry as opposed to a sacrificial heat shield. 

SpaceX is aiming to use the design for test flights during 2019.