Single-stage-to-orbit/ko
단-단-궤도 기체(혹은 SSTO,단발궤도선,단단궤도선)는 하드웨어 분리 없이 궤도에 도달하는것이 가능한 모든 기체를 지칭한다. 일반적인 SSTO는 runway 혹은 launchpad에서 이륙하며 기체의 연료만 사용하여 궤도에 도달한다. SSTO로 분류되기 위해서 궤도 이탈 혹은 대기권 재진입이 필수적인것은 아니며 궤도에서 연료 재보급을 할수도 있다. 항공기 형태의 단단궤도선의 설계는 일반적으로 우주선의 기능과 항공기 기능을 동시에 필요로하며, 대기권 외부와 내부 모두에서 항공동역학적 모델과 크기의 변화 없이 작동하도록 설계되어야한다.
Contents
연혁
- C7이 0.12 버젼의 우주항공기 관련 모드팩을 출시하기전에는 KSP 진정한 우주항공기는 없었다.
- 우주 항공기는 KSP 버젼 0.15에 공식적으로 포함되었으며 SPH 즉 우주 항공기 격납고도 동시에 포함되었다.
SSTO 설계를 위한 접근법
SSTO 는 다단 로켓과 비슷하게 여러 엔진을 같이 사용할수 있다, 하지만 우주 항공기를 제작하는데는 여러 문제가 있다.
일반적으로 SSTO에는 2가지 형태가 있다. 하나는 궤도 우주 항공기로 활주로에서 수평으로 이륙하여 수평으로 착륙하는 형태. 수직으로 이륙하여 수직으로 착륙하는 형태가 있다.
When it comes to choosing engines for SSTOs there are two primary things that need to be addressed, power to weight ratio and efficiency.
Solid fuel rocket-powered SSTOs are less than ideal since the thrust can not be controlled or vectored in any meaningful way and is unable to use fuel located on other parts of the spacecraft.
Air breathing engines, although useless in space, are quite popular launch engines for SSTOs due to their extreme fuel efficiency which allows the SSTO to conserve precious rocket fuel until an altitude where air breathing engines are no longer effective.
Liquid fuel rockets are ideal for SSTOs due to the ability to control thrust levels as well as the ability to thrust vector. Many SSTOs use aerospike engines due to their excellent power to weight ratio and efficiency. The inability to attach separate stages onto aerospike engines has no effect on SSTO design.
Whether rocket-powered or air-breathing, a reusable vehicle must be rugged enough to survive multiple round trips into space without adding excessive weight or maintenance. In addition a reusable vehicle must be able to reenter without damage, and land safely.
An example stock craft which is a working single-stage-to-orbit spaceplane is the Aeris 4A.
Issues to consider while constructing
Spaceplane construction is far more involved and complex than rocket design. Whereas when designing rockets one only needs to pay attention to structural stability, center of gravity, and center of thrust, when designing spaceplanes one also needs to be concerned about the center of lift, angle of attack, as well as aerodynamic drag due to the non-symmetrical vertical nature of aircraft.
Features and benefits
- Can be more efficient at reaching orbit than multi-stage rockets when using air breathing engines. That is because they use intake air instead of oxidizer while in the atmosphere, reducing weight and fuel requirements.
- Does not jettison expensive engines and structure.
- Prevents having to recover and refurbish jettisoned components.
- Can operate like an aircraft within the atmosphere.
Disadvantages
- Spaceplane type SSTOs cannot be as heavy as a vertical rocket due to structural limitations.
- Spaceplane SSTOs require a solid grasp on aerodynamics.
- Very fuel inefficient for carrying heavy loads into orbit.
- Typically do not carry enough fuel for inter-planetary travel.
- Harder to design than multi-stage rockets.
See also
- Single-stage-to-orbit on Wikipedia
