Difference between revisions of "Tutorial:Mun Landing/zh-cn"

Revision as of 08:11, 11 May 2020

Mun

这个教程会告诉你如何把小绿人成功降落在Mun上.

建造登月火箭

从Kerbin往返Mun的火箭通常来说非常非常的重。理想情况下，登月火箭会有3-4级（尽管更多或更少也不是不可能）。

从上到下地看：

典型的Mun着陆器

• 最顶级（着陆器）这一级应该在Mun轨道上启动，并且能够抵达Mun的表面再回到轨道、Kerbin轨道，最后返回Kerbin的大气层。听上去任务艰巨，但是这些很多都发生在低重力加速度以及无大气层的情况下，所以做到这些并不麻烦。几个油罐，一个降落伞，以及一个轻型火箭发动机就可以完成任务（注意建议使用着陆架，RCS和SAS但它们不是必需的）。

注意：也可以把这一步分为两个阶段，先着陆，然后再回家。但这只是对质量更重、更加复杂的着陆起来说。

与着陆器相连的第二级

• 中间级(轨道转移) 这一级应该在进入Kerbin轨道之前/之时启动，并且应在进入Mun轨道之时/之后启动，这取决于你的第一级火箭效果如何.另外,这一级不应该提供比最顶级更多的燃料.

注:将这一级与最顶级合并也是可以的,尽管这并不被推荐.

• 最下级 (发射) 这一级应该足够大以至于能将你的飞行器送入(或至少接近)[[Kerbin/zh-cn|Kerbin]轨道.一般来说,这一级推荐与一些可分离的固体推进器(SRBs)一起使用，虽然这不是必要的.这一级是用来把尽可能多的部分带入轨道,因为你并不会让它在接下来的旅程跟着你.如果你的中间级足够有力,你也可以只是用这一级来进入亚轨道,然后用中间级进入轨道, 就像Saturn V一样.

注:你可以根据自己的喜好来把这一级分为两级或更多.更高级的玩家会把可拆卸的燃料罐合在一起来减轻重量.

一些提醒. 在最顶级把越多的燃料罐合在一起, 你在下面级的就需要更多的发动机,如此循环,对于初学者来说,在第一级应使用1.25m的部件开始,而不是2.5m的部件.

第一步-发射进入Kerbin的轨道

我建议你把一杯水放在旁边,因为你在做这件事时会十分紧张,喝水能使你冷静下来.

这次发射就和任何一次标准的发射一样, 只不过这次的场面更大罢了. 如果你还没搞清楚如何做，请阅读这篇有关 如何入轨 的教程.

• 在你的速度在大约 100 m/s 时,开始把你的飞行器调整为朝向西方(即向右，同时导航球的橙线向下). 我们要进入一个平的且沿赤道的逆时针轨道 (就和Mun一样).
• 尝试把你的轨道调整到约150,000 m的圆周轨道, 尽管任何在大气层(70,000 m)以上的轨道都可以接受.更高的轨道是不被推荐的,因为让一个宽的圆周轨道仅仅用来到达Mun会浪费更多燃料.

理想情况下, 直到你入轨之前你都不想丢弃你的第一级火箭. 如果你的火箭的第一级不足以进入轨道,尝试加一些可分离的燃料罐.

第二步:前往Mun

一个极其简单的插图:如何只通过单一轨道进入Mun轨道.

要想从Kerbin轨道转移至Mun，你应该让远拱点触及Mun轨道。

• 如果你想第一次变轨就被Mun捕获，等待Mun在地平线上出现。一个好方法是，当前轨道距离Kerbin每100千米多等待2秒。等完以后，开始顺向加速，同时注意你的星图：远拱点向Mun轨道移动。也可以这样想：当Mun在12:00方向时，火箭应该在4:00方向加速。如果你做好了这一点，你在第一圈就会被Mun的引力捕获。

• 如果你因为什么原因没有被Mun捕获，只要保证远拱点触及Mun轨道。抵达远拱点时再次顺向加速以加宽你的轨道与Mun轨道的接触面（但不要让它变圆！）。这会提升你被Mun捕获的几率，而你只需要在完成之前等待或时间加速。

Step 3 - Munar Orbit

• When you enter the Mun's sphere of influence, turn your craft around and apply retro thrust. Keep it going until you are below escape velocity and are orbiting around the Mun. Otherwise, you will return to Kerbin's gravity well or, worse, fly into orbit around Kerbol.

• Because the Mun's gravity is substantially weaker than Kerbin, your orbital velocity will not be very high. Aim for a nice, circular orbit at an altitude no higher than 200,000 m. Because there is no atmosphere, you do not have to worry about drag at any altitude.

Step 4 - Landing On The Mun

Select your landing site along your orbital trajectory. If you want Kerbin to remain visible from your landing site, select a location along your trajectory on the near side of The Mun. Wait until you are about to pass over it.

• Once you are above it, kill your horizontal velocity until the yellow marker sits at the top of the Navball.

• Eject any stages beneath the lander if you haven't already done so.

• Begin a slow, vertical descent. Do not tip your lander over!! Keep an eye on that yellow circle with the X in it on your navball, and stay pointed at that.

• At 50,000 m begin to reduce your velocity. It should probably not be any higher than 300–400 m/s at this point. When you reach 10,000 m, reduce your velocity to below 100 m/s.

• At 2,000 m altitude, you should reduce to your final descent velocity of 6–12 m/s. Any higher and you risk damaging the lander (and killing/stranding your brave astronaut on the Mun). Get your landing gear down if you haven't already done so.

• If you are confident in your landing skills, aim for a flat surface to reduce complications during landing/takeoff. Typically the best place to find these spots is either on top of a hill, or at the bottom of a crater.

• Gently touch down at 6 m/s with as little horizontal velocity as possible.

Congratulations! You've landed on the Mun. Take your Kerbal(s) out for an EVA so they can stretch their legs, jet around, and plant a flag!

A C4N Lander

Step 5 - Returning To Orbit

Getting from the Mun back to Kerbin is, fortunately, much easier. Before you attempt to do so, make sure that you have enough fuel for the return trip. If not, consider a rescue mission with a better-designed rocket.

• Begin a slow vertical burn headed east, and try to get a low, circular, equatorial Munar orbit. You do not need a lot of thrust for this.

• Aim for an apoapsis around 200,000 m, and when you reach it apply forward thrust to circularize your orbit.

Step 6 - Back To Kerbin

• To get back to Kerbin the easiest way (as suggested by Scott Manley) is to burn prograde at the point in your orbit where you're moving opposite to the direction the Mun is going in its orbit around Kerbin. If you are orbiting around the Mun in the same direction as the Mun is around Kerbin, then burn prograde when you are between Mun and Kerbin, otherwise you need to burn prograde on the far side of the Mun.

The effect of this maneuver is increasing your speed relative to the Mun but reduce your speed relative to Kerbin as you are burning in opposite direction to movement of the Mun around Kerbin. This helps to easily get a Kerbin orbit with a the lowest point of orbit (periapsis) close to Kerbin. Can be counter-intuitive if you need to burn on the Kerbin side, as your Mun apoapsis will initially head away from Kerbin, don't worry about this and keep burning until the Mun apoapsis exits its sphere of influence.

• Burn until you have a Kerbin orbit trajectory in the map view with a Kerbin periapsis below 20 km. This height or lower will guarantee you will reenter the atmosphere in one orbit.

Step 7 - Landing On Kerbin

• When you get nearer to Kerbin you can adjust your landing point if you like. Maybe try aiming for somewhere close to the KSC. If you are in Career mode, you get rewarded with more money salvaged the closer you land to KSC, but it's not easy! Don't bother in Sandbox or Science mode - it's not necessary.

• If you are worried about coming in too fast, aim for a very shallow descent to aerobrake and bleed some of that extra velocity off.

Assuming you included a parachute in your design, and it isn't ripped off, congratulations on your first successful Munshot.

Other Ideas

Land a Rover

Attempt a Munar Rendezvous

Establish a permanent settlement on the Mun.

Land on Minmus (video)

See also

• Mun For Dummies: Travelling to the Mun and Back by nicnacnic (For Version 1.0 to 1.2)
• Tutorial:Moon landing using mods
• Tutorials