Rocket Lab CEO Peter Beck shared more details on the company’s next launch, which is set to take off from its New Zealand facility on May 15. The Electron vehicle will be carrying satellites from BlackSky, but delivering that payload is only half of the mission: the other half will be recovering the booster stage after an ocean splashdown.
This is the second of three planned booster recovery missions, part of Rocket Lab’s long-term plan to reach reusability for its launch vehicle, an achievement most famously held by its competitor SpaceX. The first recovery mission, dubbed “Return to Sender,” successfully splashed down in the Atlantic in November. While Beck told reporters Tuesday the condition of that booster “was remarkable,” this upcoming mission nevertheless features a number of component and system upgrades aimed at further fortifying the booster.
Most notably, the booster will be equipped with a redesigned heat shield made out of stainless steel, rather than aluminum, “designed to carry the reentry loads as well as the ascent loads,” Beck said. Electron must endure temperatures as high as 2400ºC during reentry, conditions the original equipment wasn’t intended to handle.
The company is also introducing what it’s calling the Ocean Recovery and Capture Apparatus, or ORCA, a dedicated system to help lift the rocket stage out of the water and onto the deck of a ship. Rough seas in November presented a challenge to the recovery effort, though ultimately the booster was not damaged.
The mission will also reuse components from the recovered booster, which (although the booster itself was dismantled) were subsequently inspected and requalified for flight. “From here on in, we should be able to reuse this system on every single launch vehicle that we’ve been bringing back,” Beck said.
Rocket Lab is pursuing a unique route to reusability. As opposed to the approach from SpaceX, whose Falcon 9 rockets use powered decelerations and landings, Rocket Lab’s approach with Electron is to decelerate the vehicle passively using the atmosphere and a parachute.
The reentry method is constrained by the size of the launch vehicle, Beck explained. “You don’t really have that ability to carry extra fuel to do maneuvers or deceleration burns or anything like that,” he said. Instead, the vehicle enters engines-first and propagates a massive shockwave on its journey back to Earth, carefully managed to reduce peak heat on its vulnerable parts. This results in a nearly negligible payload reduction: about 10%, as opposed to the 30-40% required for a propulsive landing. These are very tight margins, Beck acknowledged. “This is not a simple thing to do. It sounds pretty basic — let’s just bring the stage back and put it under a parachute and splash down — but actually, doing it with no significant reentry elements and just using the atmosphere to do all the work is really challenging.”
The final splashdown recovery mission will take place before the end of 2021, Beck said, and will include improvements to the decelerator and a more general block upgrade. Once these missions are complete, Rocket Lab will turn to its ultimate goal: to do away with splashdown recovery altogether and to retrieve the booster mid-descent under its parachute using a helicopter.
Looking ahead, the company’s next rocket will be the Neutron, “a vehicle designed for reusability from day one,” Beck said. The Neutron will be much larger than its predecessor and capable of lifting heavier payloads to orbit. He estimated that Rocket Lab will construct one Neutron rocket per year and aim to operate a fleet of four to begin with.