Returned stage in tow, photo by Rocket Lab
Step sound
The video was filmed with a camera installed in the transition compartment of the first stage. The camera did not transmit data over the radio channel, but recorded it on a USB flash drive and made a soft landing along with the step. The sound on the video was formed due to transmission to the microphone through the stage housing and the container with the exhaust chamber of the working second stage engine. The video is not just cool in itself, but also in a peculiar way complements the legendary historical footage: at the dawn of cosmonautics, when it was not possible to transmit video in high quality, they did the same - they put cameras on a rocket, then dropped them with their own parachute and radio beacon for searching, or removed an armored capsule with a film from the debris of the step. So if a microphone was also installed on those cameras, then, for example, a camera,standing in the transition compartment of a Saturn IB launch vehicle would record a similar soundseparating stage "S-IVB" with the ship "Apollo".
Also in the video, an attentive viewer can see three battery packs (two on the left, one on the right), which drive electric pumps that supply fuel to the second stage engine. During the flight, the two battery packs are dropped, further lightening the stage.
Results and plans
The company Rocket Lab, which created the Electron launch vehicle, announced in the fall of 2019 its intention to make the first stage reusable. Air pickup was chosen as the landing method - the stage will descend by parachute, for which the helicopter will pick it up and take it to the assembly and test complex. In December 2019 and January 2020, at 10 and 11 launches, two experiments were carried out - additional equipment and transmitters were put on the stage and collected data on its behavior during descent. And recently, on November 20, the next stage of testing was carried out - the stage turned aft forward, braked in dense layers of the atmosphere and opened parachutes, on which it descended to the surface.
Moment of splashdown The
head of the company Peter Beck, a couple of days later, saidadditional information for the press. First of all, the test was completely successful, they are very satisfied and confident in the feasibility of the reusable first stage. The stage was safely oriented and was heated during deceleration in dense layers of the atmosphere. The pilot parachute and the cable of the pick-up system opened at two speeds of sound, then the brake parachutes slowed down the stage, and after opening the main canopy, it splashed down at a speed of 9 m / s, 1 m / s slower than expected in the calculated area. The telemetry was successfully broadcast to the ship when the stage disappeared over the horizon for a ground tracking station. The rough seas made towing more difficult, five-meter waves tore off the containers in tow and slightly damaged the step. The towing took less than 48 hours. Some step details look like new,but about their future, we can only say with confidence that the stage will be disassembled and sent for study, especially since the loads during braking turned out to be stronger than during removal. The hull is made of composites, not metal, like many other launch vehicles, so pieces will be cut out of it and the condition is examined. Now, during the transition period, the stage will have partial reusability - the components that have successfully passed the testing will be put on the next stages, and they will thus be reused. Specifically, at this stage, most likely, the engines, which, together with the tail section, were the first to hit the water, will most likely no longer - "after what happened to them, it would be wrong."The hull is made of composites, not metal, like many other launch vehicles, so pieces will be cut out of it and the condition is examined. Now, during the transition period, the stage will have partial reusability - the components that have successfully passed the testing will be put on the next stages, and they will thus be reused. Specifically, at this stage, most likely, the engines, which, together with the tail section, were the first to hit the water, will most likely no longer - "after what happened to them, it would be wrong."The hull is made of composites, not metal, like many other launch vehicles, so pieces will be cut out of it and the condition is examined. Now, during the transition period, the stage will have partial reusability - the components that have successfully passed the testing will be put on the next stages, and they will thus be reused. Specifically, at this stage, most likely, the engines, which, together with the tail section, were the first to hit the water, will most likely no longer - "after what happened to them, it would be wrong."Specifically, at this stage, most likely, the engines, which, together with the tail section, were the first to hit the water, will most likely no longer - "after what happened to them, it would be wrong."Specifically, at this stage, most likely, the engines, which, together with the tail section, were the first to hit the water, will most likely no longer - "after what happened to them, it would be wrong."
The step on the way to the assembly and testing complex, photo by Rocket Lab.
Ropes, parachutes and additional equipment for converting the step into a reusable step are expected to subtract 10-15 kg from the payload, which will practically not affect the carrying capacity and, as planned, will be compensated improving other parts. (see different wayssoft landing). The thermal protection coped with the load successfully, but the battery blocks were sintered, as expected. Now that the load is accurately measured, the thermal protection will be improved. The goal of Rocket Lab is to catch the rocket in the air, bring it to the start, put the second stage with the payload, refuel, charge the batteries and launch. Ideally, this can happen as early as next year, but, of course, everything will depend on the success of further tests, Beck compared the work with the Pareto principle - the remaining 20% of the road will take 80% of the effort, and there will be no attempts to pick up until quality data on the flight dynamics are obtained. , the steps will splash down into the ocean. So far, the launch manifesto contains only new launch vehicles. Rocket Lab has already achieved a production rate of about 30 days per rocket, and reusing the first stage of courseif its post-flight maintenance takes less effort than making a new one, it will further accelerate the work.
Missions with a soft landing attempt will be indicated by a red stripe on the hull. The helicopter for picking up the stage will be located on the ship near the area of the fall and will take off simultaneously with the launch of the rocket. The stage will calculate in real time the exact area of the fall, and without specification it is rather small, a few square kilometers, and broadcast it. If the parachutes fail, the helicopter is safe - the step will fall in a completely different area. The December launch will take place without experiments on reusability, but the next attempt to water down the stage may occur at the beginning of 2021. Nobody is working on a soft landing of the second stage at Rocket Lab yet.
The final joke is that Peter Beck promisedon twitter eat your hat live if the rung returns in good condition and confirms reusability. Despite persuasion not to do so, the promise is still in effect, and one can only hope that the wool hat will be replaced by something more edible.