Going to be interested in how they make that work with the intended recoverability of the booster. Excitement guaranteed, for sure!
I think Soyuz boosters currently do hot staging, the interstage is open IIRC.
Aren’t the batteries and electric motors driving the grid fins at the top of the booster? That and the entire interstage are gonna get blasted with the thrust plume of three Raptors. Reinforcing them enough that it doesn’t affect planned reusability targets could take a bigger bite out of the payload than they get from hot staging.
That said, assuming the booster doesn’t get royally annihilated immediately, they’ll surely do a thorough analysis on just how much damage the booster takes. Might be that hot staging doesn’t work out for regular use, but they’ll keep it on hand for launches that need every last bit of delta-V.
I think Soyuz boosters currently do hot staging, the interstage is open IIRC.
You are correct. I believe most Russian rockets have used hot staging. It may be destructive, but it works.
Aren’t the batteries and electric motors driving the grid fins at the top of the booster? That and the entire interstage are gonna get blasted with the thrust plume of three Raptors. Reinforcing them enough that it doesn’t affect planned reusability targets could take a bigger bite out of the payload than they get from hot staging.
That was my first thought, or that the header tank up at the top might not like being heated like that.
I’m sure they’ll figure out pretty quickly if it works or not.
He used an interesting way to describe the interstage I think. For hot-staging I’ve only seen the completely open structure with rods, arraged in triangular patterns, connecting the stages. I wouldn’t have used the word “vent” to describe something like that, so I wonder if spacex is implementing it differently.
A ring section for Superheavy with an odd pattern of cutouts was spotted a while ago at Starbase and the SpaceX watchers speculated it was for hot-staging, turns out they were right.
Here’s the model they came up with based off of that ring section:
