宇航员风险管理指南:结果预测和事件概率

认知

【Background】

The Astronaut’s Guide to Risk Mitigation: Predict the Consequence and Probability of Events , with Chris Hadfield, Retired Canadian Astronaut and Author, An Astronaut’s Guide to Life on Earth
It goes without saying: Space flight is a risky activity. Rockets can fail. Fuel tanks or the ship itself can be punctured by tiny meteorites. So rocket scientists have become experts in risk-mitigation. Their approach is generalizable to any problem-solving situation. Fundamentally, it comes down to evaluating the likelihood (probability) and the consequences of all the risks you face in a given set of circumstances, then prioritizing more probable risks with more serious consequences.

今天我们请到了克里斯·哈德菲尔德。他是一位来自加拿大的退役宇航员,曾担任国际太空站的指挥官。他著有《宇航员地球生活指南》。今天的课程中,他将为我们讲述如何通过预测事件的概率和结果来缓解风险。
毫无疑问,宇宙飞行是一个颇有风险的活动。火箭可能会发射失败;燃油舱或是飞船本身可能会被小陨石刺穿。所以火箭科学家们变成了风险缓释方面的专家。他们的方法可以推广到其他任何需要解决问题的场景中。根本上来说,它是在评估一些特定的情境下,你可能面对的所有风险的概率和结果,接着优先考虑那些发生概率更大、后果更严重的风险。那我们来看看,宇航员的风险缓释策略是如果在理论和实践中形成的呢?

【Course】

Risk Mitigation in Theory 风险缓解理论

Trying to deal with risk is a personal choice, but it’s also pretty well-documented. For example, what’s the risk of getting hit by lightning? It’s pretty low. I mean, do you know anybody that’s been hit by lightning? It only happens occasionally, but the consequences of getting hit by lightning are really high. If lightning hits you, you’re pretty much dead. Or if a meteorite comes smoking through the atmosphere and crashes into you, you’re toast. You’re done. So that balance between consequence and probability is what risk is all about, and that’s how we predict risk.
风险处理是一个个人选择,但它被很好地记录了下来。例如,被闪电击中的风险是什么?挺低的。我是说,你认识什么人被闪电击中过吗?它只是偶尔发生。但被闪电击中的后果却非常严重。如果你被闪电击中了,你基本就死定了。或者如果一块陨石擦过大气层朝你撞来,那你就被烤焦了,你就完了。所以风险就是有关后果和概率之间的平衡,这就是我们预测风险的方式。

If it’s a thing that has no consequence, like the risk of a fly landing on my shoulder, well, it might happen, but there’s no consequence. Who cares if a fly lands on my shoulder? It doesn’t matter. So in that case it would be way down in the lower left side of a matrix of some probability and some consequence. There are some things that have extremely high consequence – a lightning strike – but very low probability. So how much do you actually have to prepare for those? It’s when you get the worst of both, where you get a high probability – this is actually probably going to happen – and it has a high consequence. Like having a car accident. In your life, sometime, you’re probably going to have an accident with your car and it can have very high consequence. Then, you need to deal with it – you need to somehow mitigate and change that risk. So you do. We have rules on how to drive a car. You have to get a license. In your car it has crumple zones. We do crash tests. You have an airbag to protect you. You have your harness, your seat belt, strapping you in. You practice, you learn how to drive.
如果这是一件没有后果的事,比如一只苍蝇落到我肩膀上的风险。嗯,这是有可能发生的,但不会有什么后果。谁在乎苍蝇落到肩膀上呢?这无关紧要。所以如果把概率和后果同时放在一个矩阵里,这件几率大后果小的事将落在最左下方的位置。也有些事情有着极大的后果,但几率非常小,比如一个闪电雷击。所以你对于这些都准备得如何?当两者都最糟的时候,即很大的概率和很严重的后果,这种情况实际上也是很有可能发生的,比如车祸。在你的一生中,某个时刻,你可能在车里发生一些意外,它也许会有很严重的后果。那么,你需要面对它,你需要想个办法缓解这种风险,去改变它。所以你这么做了。我们有合理驾驶的规则。你必须考出驾照。你车里有撞击缓冲区。我们会进行撞击测试。你还有一个安全气囊保护你。你有你的背带、安全带,把你固定在车里。你必须练习,然后学着驾驶车辆。

All of those things are just structured to mitigate a risk that has high probability and high consequence. You can approach anything that way. Just say, what’s the risk and what’s the chance that it’s going to happen? What’s the consequence of it happening? And then you can decide how much time you’re going to invest in preventing that event from happening in your own life. It’s just sort of engineering, and it’s the way we fly rocket ships, but maybe it’s not a bad thing to just analyze your own life with as well. What are my risks, what are my probabilities, what should I change, what should I get ready for?
所有的这些事构成了对于高概率且后果严重之事的风险缓释策略。你可以用这个方法处理任何事。比如,这件事可能发生的风险和几率多大?如果发生了,后果如何?然后你再决定为了让自己的人生中不发生这样的事而需要投入的时间。这有点像工程设计,这也是我们驾驶火箭飞船的方法。或许,就用它来分析你自己的人生也会很有用。我的风险是什么,我的概率是什么,我可以怎么改变,我需要准备些什么?……

Risk Mitigation in Practice  风险缓释实践

It’s fun to look up and see a shooting star. But of course, what a shooting star is is a rock coming in from the universe and burning up in the atmosphere. When you count up all those rocks, the Earth gets hit by 50 tons of rock a day. 50 tons of meteorite hit our Earth everyday, and every ounce of those go by the space station – because it’s up there. So there’s a definite risk on board the space station of having a meteorite punch a hole in the wall of the spaceship. So that’s a risk. Now the question is, what are the consequences of that happening and what’s the probability of it happening? And how can we deal with both of those?
抬头看到流星是很有意思的。当然,流星其实是从宇宙飞来的一块岩石在大气层燃烧形成的。如果你统计这些所有的岩石,那么地球每天会被50吨岩石撞击。50吨陨石每天都在撞击我们的地球,而其中每一盎司都会经过空间站,因为它在地球的上方 。所以,空间站的墙体被一块陨石击出一个洞几乎是一个确定存在的风险。这是一个风险。现在的问题是,这件事如果发生了的后果是什么?发生的几率又有多大呢?以及我们如何同时计算概率和后果?

So the probability of a rock punching a hole, well you can just sort of do the math and think about it, and we realized that over a 30-year lifespan of a space station there’s a certain fairly high percentage that a rock will at some point punch a hole in it. So we put armor on the outside of the space station. It has another whole protective layer of what we call Micrometeorite Orbital Debris protection – MMOD protection. And it’s not going to solve all problems, but it decreases the chances of one of those rocks coming through. We also, if we know something’s coming that’s big enough, we can actually fire the engines on the space station and get it out of the way – another way to avoid getting hit.
一块陨石撞击出一个洞的概率,嗯,你可以试试算一算,然后想想,我们会发现在空间站30多年的生命周期里,有相当大的概率会被陨石撞击出一个洞。所以我们在空间站外部套上盔甲。空间站外面有一整层保护层,我们叫它微流星体和轨道碎片防御系统,简称MMOD防御系统。它虽然不能解决所有的问题,但是它减小了飞船被陨石击中的几率。同时,如果我们发现飞来的东西体积很大,我们可以发动空间站的引擎,把它从身边赶开,这是另一种避免被击中的方式。

But there’s always going to be some chance of just something unplanned just punching a hole. So then we change inside. We recognize that if we get a hole punched in the ship, how do we react? How do we stop it from causing bodily harm to us and ruining the spaceship? And so we practice all the time. We have a bunch of sensors inside to measure a drop of pressure, including our eardrums – they’re a pretty good sensor. If you feel your ears starting to pop, then you know the pressure’s dropping. And then we have alarms that go off in the middle of the night, and you know ok, I need to go get the mask and I need this equipment, follow this procedure, do all of these things. And then we immediately have a long, carefully written and practiced sequence of procedures for how to deal with a pressure loss. And initially we’re worried about saving our lives, but if the leak is slow enough then you run around the station in a logical sequence and start closing hatches, and try to lock off wherever the leak might be so that that portion might depressurize but the rest of everything’s going to be ok. And we practice that, and we constantly improve it and think about it, and we’re good at it.
但即使是这样,也还有几率被一些不在计划中的物体击中。所以我们要再从内部改变。我们需要认识到,如果飞船被击出了一个洞,我们会如何应对?我们怎么样让它不要给我们的飞船带来整体性的伤害导致毁了这艘飞船?所以我们经常训练。飞船内部有许多传感器,可以感知内部压力突然的降低,还包括我们自己的耳膜—-它们也是很好的传感器。如果你感觉耳压突然发生变化,那你就应该知道压力开始下降了。我们还有半夜会响起来的警报,那时候你就知道,好的,我需要起来戴上面罩,我需要这个装备、根据这个流程做这些事。接着我们就有了一个很长的、非常详实的、并且经过实践的一系列压力损失处理流程。一开始我们会担心自己的生命,但当泄漏速度非常慢时,你就有足够的时间按照逻辑顺序跑遍整个空间站,开始关闭舱口,尝试切断泄漏所在点,让那块地方单独减压而不影响全舰。我们反复训练这个流程,也常常思考、改善它,所以我们变得很善于处理这类问题。

And that combination of recognizing there’s a risk, figuring out the consequences, looking at the probability, and then working on how we’re going to respond and prevent, that drops the risk down to a level that we can go live on a spaceship. We know that that risk exists, but we’ve analyzed it and worked on it and mitigated it enough that we can safely live on a spaceship for decades. And between the Russian space station Mir, which was launched in 1986, and the International Space Station, which we started living on in 2000, we’ve had lots – thousands and thousands – of meteorites hit the ship, but never once has a meteorite punched a hole, and if it does, we’re ready to deal with it.
而这一整个组合:从发现有风险,到找出后果,计算概率,思考如何应对和避免,这个组合使大多数风险降低到了可以让我们生活在一艘宇宙飞船上的水平。我们知道风险会产生,但我们分析过、调查过、缓释了它,所以我们可以安全地在飞船上生活数十年。从1986年发射的俄罗斯空间站米尔到我们从2000年开始生活的国际空间站,有成千上万的陨石击中过飞船,但从来没有一块击穿过。如果它真的击穿了,我们也已经准备好应对这种情况了。

【Summary】

Risk Mitigation in Theory
• Risk lies in the balance between consequence and probability.
• Risks that have both high consequence and high probability should be mitigated first.
• Ask: What’s the risk? What’s the chance that it’s going to happen? What’s the consequence of it happening? Based on your analysis, decide how much time and other resources you’ll commit to preventing the event from happening.

Risk Mitigation in Practice
•To guard against the high-risk event, first take measures to decrease the chances that it will happen. Ask: What can we do to avoid this event altogether?
•Next, equip yourself with the tools to monitor the effects of the high-risk event. How will we know when the event happens so that we can respond quickly?
•Finally, create a response plan. What systems and procedures will we have in place to manage the negative impact of the high-risk event? How will we recover?
•Practice your plan over and over again. Keep improving it.

一、风险缓释理论
风险即是后果和概率的平衡
具有大概率和严重后果的风险应该被优先缓释。
问:风险是什么?发生的几率多大?发生的后果是什么?基于你的分析,再决定为了阻止这件事的发生,你要投入多少时间和资源。

二、风险缓解实践
为了避免高风险事件的发生,首先要采取措施减小事件发生的几率。问:我们能一起为避免这件事的发生做什么?
接下来,为了这个高风险事件可能的影响做准备。我们如何知道这件事什么时候发生,从而可以更快地采取应对措施?
最后,制定一个应对计划。我们有什么系统和流程可以用来处理这类高风险事件的负面影响?我们如何从中恢复?
一遍遍训练这个计划流程,并不断完善它。