Starship from SpaceX is going to have a new landing sytem after two explosions
SpaceX will test changes to its starship’s landing system, the Starship, in the next prototype. The objective is to avoid the catastrophic failures that occurred in the two previous tests: both the SN8 and SN9 took off and reached an altitude of 12 km without difficulty, but both exploded at the time of landing, although for different reasons.
Starship prototypes have three Raptor thrusters, two of which are needed for a maneuver called “Flip and Burn”, when the spacecraft fires two thrusters to reorient upright and land smoothly. In the case of SN9, one of them was not activated. As a result, the spacecraft failed to complete the maneuver and collided with the ground.
An obvious solution would be to activate the three thrusters, instead of two, at the time of the maneuver. So, if one of them fails there is redundancy. But that would generate too much thrust, causing the spacecraft to rise again instead of descending smoothly.
Good analysis. We’re working on lowering min throttle of Raptor, so that there is engine redundancy throughout the landing burn.
— Elon Musk (@elonmusk) February 13, 2021
To get around the problem, SpaceX works in a “middle ground”: according to Elon Musk, the company’s CEO, engineers are working on a reduction in the minimum power of the engines. Thus, there may be redundancy on landing.
The SN10, that is already installed on a launch pad at SpaceX’s facilities in Boca Chica, in southern Texas, will be the first Starship to attempt the “Flip and Burn” with three engines at reduced power. According to Musk, his degree of confidence in the success of the test is 60%, double that of the SN8 and SN9 tests.
Success on landing probability is ~60% this time
— Elon Musk (@elonmusk) February 14, 2021