According to NASA, space agency engineers are preparing to test subscale prototypes of space capsulesthat will use rotor blades rather than parachutes to slow their descent once they reenter the Earth’s atmosphere.
Why NASA is testing rotor blades
The idea of using rotor blades rather than parachutes stems from the fact that helicopters have far greater control and stability that do vehicles using parachutes, according to NASA. The rotors on a reentering space capsule would not be powered, but rather would use the passing of the air through the rotors to rotate them as the capsule descends, a process called autorotation. Helicopters have used this process to make emergency landings for years. In theory, a rotor blade-equipped spacecraft could land with the accuracy of a helicopter, on a runway or even a heliport on top of a building.
Testing rotor blade equipped capsules
The space agency engineers are testing the rotor blade-equipped capsules in the massive Vehicle Assembly Building, where both the space shuttle and the Saturn V were put together prior to launch into space, according to NASA. The blades have been remotely controlled during drop tests to change their pitch and slow the descent of the capsule before it landed on a stock of foam.
Before the advent of the space shuttle, the descent of NASA’s manned spacecraft were slowed by parachutes until they splashed down in the water. The Apollo Parachute Landing System was capable of decelerating and stabilizing the Apollo command module during descent to a landing zone in the Pacific Ocean. However the landings were not exactly pinpoint accurate and require a large recovery fleet.
The parachute landing system for the Orion Multi Purpose Crew Vehicle, the spacecraft envisioned for deep space missions by NASA, was recently tested successfully, according to NASA, including a simulation of landings in water, as envisioned for astronauts, in a back to the future scheme. Modern GPS and other technology gives NASA the hope that an Orion can splashdown close to the coast of California and could be picked up with a land based helicopter or, as SpaceX has done with its Dragon spacecraft, a crane-equipped barge.
The concept of using rotor blades to land a spacecraft was tried in the 1990s by a company calledRotary Rockets, which attempted to build a single stage to orbit reusable spacecraft. According to Encyclopedia Astronautica, the Roton Rocket, as it was called, would launch as a rocket with the rotor blades folded against the sides of the vehicle. When the Roton reentered, the four rotor blades would deploy and use the autorotation maneuver to slow and control the descent of the spacecraft. Technically challenges and a lack of investment capital eventually killed the project around the year 2000.