How to crash an airplane – Nickolas Means | The Lead Developer UK 2016

Summary

本次演讲回顾了1989年7月19日发生的联合航空232号航班事故，讲述了机组人员如何在飞机失去所有液压系统控制后，通过卓越的团队合作和创造性的解决方案，成功将飞机降落在爱荷华州锡城机场，最终实现了185人幸存的奇迹。这一事件被视为机组资源管理（Cockpit Resource Management）的典范，强调了在紧急情况下，有效的沟通、领导和决策对团队成功的重要性。

Takeaways

• 🛫 飞行事故的教训：通过分析飞机事故，我们可以了解到机组人员如何应对紧急情况，并从中学习到宝贵的经验。
• 🚁 飞机设计的重要性：DC-10型飞机的三重冗余液压系统设计在当时被认为是先进的，但在极端情况下仍可能出现问题。
• 💡 机组人员的团队合作：在面对飞机失去全部液压控制的紧急情况时，机组人员通过有效的沟通和协作，共同应对危机。
• 🛰️ 紧急情况下的创造性解决方案：在没有标准操作程序可遵循的情况下，机组人员通过创新思维和尝试不同的方法来控制飞机。
• 👨‍✈️ 机组资源管理（CRM）的应用：通过实施CRM，机组人员能够更好地利用每个人的技能和知识，共同解决问题。
• 🤝 权力下放与集体决策：机长Haynes通过放权给其他机组人员，使得团队能够共同参与决策，提高了处理紧急情况的能力。
• 📣 确保每个声音都被听到：在紧急情况下，确保每个人的观点和建议都被考虑，有助于找到最佳解决方案。
• 🚫 避免个人英雄主义：在团队合作中，避免个人英雄主义，鼓励集体合作和共同承担责任。
• 🌐 多元化团队的价值：多元化的团队可以带来不同的观点和专业知识，有助于提高团队解决问题的能力。
• 📈 领导的角色转变：领导者的角色应从单一的决策者转变为确保团队中每个声音都被听到和尊重的协调者。
• 🛎️ 应对紧急情况的准备：通过模拟训练和准备，可以提高机组人员在真实紧急情况下的表现和生存率。

Q & A

飞机失事的原因是什么？

飞机失事的原因是二号引擎尾部的风扇盘爆炸，导致飞机失去了所有的液压系统，无法正常控制飞行。

风扇盘爆炸后，机组人员是如何尝试控制飞机的？

风扇盘爆炸后，机组人员首先尝试通过关闭二号引擎的油门和燃油切断来控制飞机，但发现控制杆被卡住。随后，机长Haynes接管了飞机的控制，并尝试通过调整剩余引擎的推力来控制飞机的飞行姿态。

为什么飞机无法使用其液压系统？

飞机的液压系统因为风扇盘爆炸产生的碎片而被破坏。所有三个液压系统的液压油量和压力都降至零，导致飞机失去了对升降舵、副翼和方向舵的控制能力。

机组人员是如何准备紧急着陆的？

机组人员通过与空管沟通，请求将飞机引导至最近的合适机场——苏城机场。同时，机组人员通知了乘务长Jann Brown，要求她准备客舱并告知乘客紧急着陆的信号。

Denny Fitch是如何帮助机组人员的？

Denny Fitch是一位DC-10型飞机的检查飞行员，他在乘客中意识到飞机遇到了严重问题，主动提出帮助。在驾驶舱中，他接管了节流阀的控制，通过调整剩余两个引擎的推力来尝试控制飞机的飞行。

飞机在着陆过程中遇到了哪些困难？

飞机在着陆过程中因为失去了液压系统，无法使用襟翼和缝翼来降低速度和增加升力。飞机以比正常着陆速度快一倍的速度接近机场，并且以极高的下降速率降落。

飞机最终是如何成功着陆的？

尽管飞机以极高的速度和下降速率接近机场，但机组人员通过精确地控制剩余引擎的推力，成功地使飞机在苏城机场的一个关闭的跑道上着陆。

飞机失事的生存率是多少？

在这次飞机失事中，有185人幸存，111人遇难。这是商业航空史上首次在完全失去飞行控制的情况下有乘客幸存的案例。

机组人员的表现如何被评价？

美国国家运输安全委员会(NTSB)认为，在这种情况下，联合航空232号机组的表现非常值得称赞，远远超出了合理的预期。

机组资源管理(Cockpit Resource Management, CRM)在这次事件中起到了什么作用？

机组资源管理强调团队合作、沟通、领导和决策。在这次事件中，机组人员通过共享信息、共同决策和有效沟通，成功地将飞机引导至机场并实施紧急着陆。

软件工程领导者能从这次飞机失事中学到什么？

软件工程领导者可以从中学到团队合作的重要性，避免个人英雄主义，确保每个团队成员都有发言权，以及培养一个包容和鼓励多样性的团队文化。

Outlines

00:00

🌟 开场致辞与背景介绍

演讲者在lead dev会议上向听众问好，并表达了与众多杰出演讲者同台的荣幸。他感谢组织者和委员会主席Mary，并简短介绍了自己——Nicolas，Well Match Health的工程副总裁。他提到自己与许多聪明人合作以改善美国医疗系统，并邀请感兴趣的听众与他交流。此外，他还透露了自己对飞机失事的研究兴趣，尽管这听起来有些奇怪。

05:02

✈️ 飞机失事的启示

演讲者分享了自己对飞机失事的特殊兴趣，特别是对驾驶舱内发生的事情感兴趣。他讲述了两种类型的飞行事故：一种是小问题由于处理不当而导致的大灾难，另一种是飞行员面对巨大困难时如何取得比预期更好的结果。他强调，他将要讲述的United 232航班的故事属于后者，这是一个在几乎无法克服的困境中拯救了半数以上乘客的故事。

10:04

🌤️ 美好的飞行日与突如其来的灾难

演讲者描述了1989年7月19日，一个在丹佛科罗拉多州的美好夏日，以及United 232航班的乘客和机组人员的到来。这架DC-10型飞机是一架老旧但值得骄傲的飞机，已经服役了18年。然而，这次看似平常的飞行在飞行中突然发生了巨大的爆炸声，飞机尾部的二号引擎风扇盘爆炸，导致机组人员必须紧急应对。

15:05

🚨 紧急情况与初步应对

爆炸发生后，机组人员迅速做出反应，试图控制飞机。他们发现二号引擎失效，并尝试按照标准程序请求降低高度并继续飞往目的地。然而，他们很快意识到情况比预期的要严重得多，因为飞机的控制系统出现了问题，飞行员无法通过常规方式控制飞机。

20:09

🛫 危机中的决策与求生

面对飞机失去全部液压系统的紧急情况，机组人员必须做出快速决策。他们尝试使用飞机的发动机推力来控制飞机的飞行方向和姿态。在此过程中，一名非当班的飞行员Denny Fitch提供了帮助，他是一名DC-10型飞机的检查飞行员，拥有丰富的模拟器训练经验。尽管如此，他们仍然面临着巨大的挑战，因为DC-10型飞机没有为完全失去液压系统的情况设计应急程序。

25:09

🌪️ 飞机失控与机组人员的协作

在飞机失控的情况下，机组人员通过协作和创新的方法来控制飞机。他们尝试了各种可能的控制手段，包括使用不同的发动机推力组合来影响飞机的飞行路径。在这个过程中，机组人员之间的沟通和决策变得至关重要。他们必须共同努力，才能有机会将飞机安全降落。

30:10

🛬 紧急降落与生存奇迹

在机组人员的共同努力下，飞机最终成功降落在了Sioux City机场。尽管飞机在降落过程中发生了严重的撞击和翻滚，但令人惊讶的是，有185名乘客在这次事故中幸存下来。这次事故成为了航空史上的一个奇迹，也展示了机组人员在极端情况下的卓越表现和团队协作的重要性。

35:16

🤝 团队合作的重要性

演讲者强调了团队合作在解决复杂问题中的重要性。他提到了机组资源管理（Cockpit Resource Management）的概念，这是一种强调团队内部沟通、领导和决策的方法。通过分享United 232航班的故事，演讲者说明了在面对挑战时，团队成员之间的相互支持和合作是如何帮助他们克服困难并取得成功的。

Keywords

💡飞行事故

飞行事故指的是飞机在飞行过程中发生的非正常事件，可能导致人员伤亡或飞机损坏。在视频中，讲述了联合航空232号航班在飞行中遭遇的严重事故，包括尾部发动机爆炸和随后的液压系统失效，这是飞行事故的一个典型案例。

💡飞机控制

飞机控制是指飞行员通过飞机上的控制系统来操纵飞机的飞行状态，包括高度、速度、方向等。在视频中，由于液压系统失效，联合航空232号航班的飞行员失去了对飞机的传统控制能力，只能通过调整发动机推力来尝试控制飞机。

💡液压系统

液压系统是飞机上用于传递动力和控制飞机控制面的系统。在视频中，联合航空232号航班的液压系统因为尾部发动机爆炸而完全失效，导致飞行员无法正常控制飞机。

💡紧急情况

紧急情况指的是需要立即采取行动以防止或减轻伤害或损害的情况。在视频中，飞机遭遇的一系列问题，如发动机爆炸和液压系统失效，都属于紧急情况，需要机组人员迅速做出反应和决策。

💡机组资源管理

机组资源管理（Cockpit Resource Management, CRM）是一种旨在提高飞行安全的方法，通过改善飞行员之间的沟通、领导和决策能力。在视频中，联合航空232号航班的机组人员通过有效的CRM，使得每个人都能发表意见和提供帮助，这对于他们最终成功着陆至关重要。

💡飞行安全

飞行安全是指采取各种措施来预防飞行事故和减少飞行风险，确保乘客和机组人员的生命安全。视频中的事故强调了飞行安全的重要性，以及通过技术和团队合作来提高飞行安全的必要性。

💡飞行员

飞行员是指经过专业训练，能够操纵飞行器进行飞行的人员。在视频中，联合航空232号航班的飞行员在面对极端紧急情况时，展现了专业的飞行技能和出色的危机处理能力。

💡紧急着陆

紧急着陆是指飞机在遇到紧急情况时，必须迅速采取措施进行的着陆。在视频中，联合航空232号航班在失去液压系统后，机组人员努力进行了一次紧急着陆。

💡团队合作

团队合作是指团队成员之间为了共同的目标而协同工作的过程。在视频中，机组人员之间的有效沟通和协作是成功应对紧急情况的关键。

💡事故调查

事故调查是指对事故发生的原因、过程和结果进行系统的分析和研究。在视频中，对联合航空232号航班事故的调查帮助揭示了事故的原因，并为今后的飞行安全提供了重要的教训。

Highlights

Nicolas Means 分享了作为工程副总裁在健康匹配公司的经历，以及他对于改善美国医疗系统的贡献。

Nicolas Means 表达了他对飞机坠毁案例的研究热情，并分享了他对飞机事故中驾驶舱动态的深入理解。

通过英国航空公司53航班的案例，Means 强调了飞行机组在面对紧急情况时的反应和决策对结果的重大影响。

Means 讲述了联合航空232号航班的故事，这是一个在遭遇几乎无法克服的困境后，成功救出半数以上乘客的案例。

在丹佛科罗拉多州的一个美丽夏日，联合航空232号航班的乘客和机组人员经历了一次意外的飞行。

飞机在飞行中遭遇了二号引擎风扇盘爆炸的灾难，机组人员必须立即作出反应以确保飞机安全。

在飞机失去二号引擎后，机组人员发现他们无法通过常规方法控制飞机，因为所有的液压系统都失效了。

联合航空232号航班的机组人员通过创造性的思维和卓越的团队合作，成功将飞机导向紧急着陆。

在飞机接近机场时，机组人员与空中交通管制的沟通展现了他们在极端情况下的专业性和冷静。

尽管飞机以超过正常速度两倍的速度接近机场，机组人员仍然设法控制飞机进行了紧急着陆。

飞机在着陆时遭遇了严重的撞击，但由于机组人员的英勇努力，大部分乘客得以幸存。

Nicolas Means 强调了机组资源管理在这次成功紧急着陆中的关键作用，以及团队合作的重要性。

通过这次事件，Means 提醒我们，在面对挑战时，我们需要避免个人英雄主义，而是要作为一个团队共同面对。

Means 鼓励软件工程领导者采用类似机组资源管理的方法，确保每个团队成员的声音都能被听到。

在软件工程领域，Means 强调了建立一个每个成员都能够发声并共同解决问题的团队文化的重要性。

Means 通过联合航空232号航班的故事，展示了在危机中卓越的团队合作和领导力如何创造出意想不到的成果。

Transcripts

so good afternoon everybody hope you've enjoyed the first day of lead dev I know

I certainly have it's quite the honor to be able to share this stage with so many

amazing speakers so thank you to the organizers and to Mary the committee

chair and all the speakers with President to us today I like Mary said

my name is Nicolas means I'm VP of engineering at well match health I work

with a lot of really smart people to help make the US healthcare system

better if you want to know more about what I do come talk to me because with a

British audience it's going to be a conversation it's not not something I

can explain from stage but another thing you need to know about me is that I am a

student of plane crashes I know that's a weird thing to say but if you want to if

you want to nerd tonight me come up to me and ask me about a plane crash that I

can't tell you the details about right off the top of my head Joe one of the

members of the conference staff did this to me last night at the speaker's dinner

and so instead of going home to the hotel and rehearsing my talk I went back

and looked up the details of British Airways incident where the windscreen

got sucked out of an airplane and the pilot got sucked out halfway and they

still managed to land and everybody survived it was British Airways flight

53 90 if you want to go look it up yourself but it's not it's not the

morbidity of plane crashes or the spectacle that fascinates me

it's the dynamics of what happens in the cockpit what the flight crew goes

through from when an incident starts to when the plane gets to the ground one

way or the other there's two kinds of ways this go there's some flight crews

that take tiny incidents and through poor reactions or poor decisions take

tiny system bolts and make them in a giant disasters then there's other

incidents where flight crews take giant problems insurmountable obstacles and

somehow managed to eke out a better outcome than they ought to be able to

and the story I want to tell you today is the story of one of the latter it's a

story of a flight crew who takes a plane that's struck with almost insurmountable

peril and manages to save more than half the people on board that's what I think

is one of the most fascinating plane crashes

aviation history the story of United 232

so July 19th 1989 was an absolutely beautiful day in Denver Colorado the

highways summer in the mid-80s scattered clouds there was a wonderful breeze

blowing in off the Front Range of the Rocky Mountains was the kind of day if

you've ever been to Denver in the summer it's the kind of day that just begged

you to go outside and do something go for a hike play around a golf it was

also a wonderful day for flying at Denver's Stapleton International Airport

planes were leaving on time everything was running smoothly and about 10:30 or

11:00 in the morning the first of the 285 passengers and 11

crew members that would eventually be on board United flight 232 started arriving

at the gate their flight that day would take them from Denver staple an airport

to Chicago O'Hare or so they thought when they cross the jet bridge if you

were in the boarding lounge that day you would have seen something like this

through the window it's a bit of an unfamiliar sight to a modern traveler

back in these days it was forbidden for planes to fly extended distances with

only two engines they had to have more redundancy than that so Airlines

invested heavily in what they called tri jets engines that had planes that had

two engines one of the wings and one mounted through the tail and

that's what you had been getting on this day specifically a dc-10 series 10

aircraft tail registration number November 1819 uniform that picture is

the actual plane you had been getting on that day it was an old but proud plane

delivered United in 1971 and had been in service since then for about 18 years

now 18 years seems kind of old for an airliner but it's really not United

would actually fly their dc-10 flight fleet well into its 30s and you can

still see these planes around the world today carrying packages and FedEx

delivery a lot of them are still operating as you got on board you'd have

seen something like this if you've been on board of Boeing triple7 recently this

cabin is just a little bit wider than that it was a wide and roomy cabin was a

quiet plane and pilots love to fly it they referred to it as the Cadillac

Fleetwood of the skies because it was such a comfortable ride and the three

engines gave it way more power than it needed so they loved

love being able to put their hand in the throttles and push them forward for

takeoff and let the power of that plane slam them back in their seats if they

took the skies around to 10:00 in the afternoon that day that's exactly what

happens it was a textbook takeoff out of Denver Stapleton they turn

east-northeast out of the airport toward Chicago and if you'd been in the cabin

at that point you'd have smelled chicken strips United was running a promotion

that summer they called their picnic lunch so if you were flying at lunch

time they would bring you a little basket cover to run white check paper

with picnic lunch in it and that day it happened to be chicken strips a few

Oreos and a cup full of cherries well about an hour into the flight

most people had finished their lunches the flight crew was beginning to pick up

from lunch Jim McKay the legendary American sportscaster from ABC's Wide

World of Sports was about 20 minutes into explaining the history of horse

racing in the in-flight movie jewels of the Triple Crown sounds thrilling I know

and about that point what had become what had been a completely normal flight

up until then suddenly changed there was a tremendous bang at the back of the

airplane passengers thought maybe a bomb had gone off the flight crew across the

plane hit the deck and grabbed the nearest armrest afraid that what they

had heard was an explosive decompression and they might be sucked out of the

plane close neither of those things what had actually happened is the fan disc in

the number two engine the tail mounted engine had exploded

on the flight deck they had just finished their lunches when they heard

this explosion first officer bill records who have been sitting in that

seat on your right there immediately yells I've got it

lunges forward grabs the yoke disabled the autopilot and starts flying the

plane by hand Dudley Dvorak the flight engineer who would have been sitting at

that control console right there on the right

starts checking his gauges and immediately notices the number two

engine is failed so he radios Minneapolis st. Paul air control center

not to declare an emergency but just to ask for clearance to lower altitude but

goes on a dc-10 I mentioned the redundancy of the three engines it

actually wasn't that big a deal to lose an engine with the reliability of these

engines built in the 70s and 80s losing engine wasn't all that uncommon so

standard procedure was just to request a lower altitude slow down a little bit

and continue on to your destination and that's exactly what they intended to do

about this point captain al Haynes who was sitting in the pilot's seat that day

asks for the engine shutdown checklist from from flight engineer Dudley Dvorak

now captain Haynes at this point was primarily concerned with making sure

that whatever happened to this number two engine didn't escalate into a bigger

crisis when engines failed it's possible that it could be catching on fire or

there could be physical damage and you wanted to avoid making the situation any

worse so we asked ugly Dvorak to start in on

the checklist the first thing on the checklist was to close the number of the

number to throttle and so captain Haynes tried to do that and could the wooden

budge the throttle was stuck so he moved on to the second step of the checklist

the second step was to shut off the fuel shutoff to this engine they tried that

as well wouldn't budge and is at this point that they finally understood that

something more than a routine engine failure had befallen their beautiful

plane that day the thing you need to know about the dc-10 is that the

throttle and the fuel shutoff are both physically coupled to the engine via

steel cable if you think about how a bicycle brake works it's the same theory

so the fact that both of those controls were jammed hold the flight crew that

there must be some significant physical damage to the aircraft

so hands into work we're trying to figure out what to do next when bill

records from the copilot seat shouts ow I can't control the plane which is a

terrifying thing to hear so captain Haynes looks over and bill records with

his arms as tense as they could be has the yoke all the way back all the way to

the left there's two things about this that terrifying the first thing is you

would never give an aircraft that kind of input at cruise speed you'd be like

driving down the highway at 85 miles an hour and suddenly jerking the steering

wheel all the way to left you would lose control of the plane if you did that but

even more terrifying than that despite the fact that that records had the yoke

all the way back which would command the plane to go up and all the way to the

left which would command the plane to turn left it was doing the exact

opposite it was descending and rolling to the right so at this point captain

Haynes yells I've got it and takes the controls from Bill records and tries to

see if he can have any effect on the control surfaces of the plane meanwhile

flight engineer Dvorak is still studying his gauges trying to figure out exactly

what's happened to his beautiful plane when he something catches his attention

he glances up from his gauges momentarily out the windscreen of the

aircraft and immediately yells were rolling at this point the plane is about

38 degrees of Bank which is pretty steep for a commercial plane it'd be pretty

uncomfortable if he were back in the passenger cabin and immediately to an

instinct that he still doesn't understand to this day captain Haynes

swats the number one throttle closed opens the number three will throttle all

the way to the firewall wide open and subsequent studies showed subsequent

subsequent simulator exercises showed that in that moment captain Haynes saved

their aircraft because after he did this the point slowly started coming back to

level pushing the number three throttle all the way up and pulling the number

one all the way back increased list on the right wing and pulled it up

counteracted the drag that the failed engine was having on the tail and with

the point now under relative control Dudley Dvorak makes the first

announcement of passengers now something I need to tell you is that this

particular dc-10 only had a 30-minute loop cockpit voice recorder and the

actual accident sequence is about 47 minutes from when the fantasy ruptures

to when the plane gets to the ground in Sioux City

so the first 17 minutes of the crash were really lost to history but

according to accounts from the flight crew and from passengers on board

what Dvorak said when a little something like this Wow waited there there we go

ladies and gentlemen we've lost our tail engine but this aircraft can fly fine

with the two remaining engines we're going to descend and continue on to

Chicago perfectly reassuring thing to say to the the people in the back of the

airplane but almost immediately after making this announcement

Dvorak finally spots the thing in his gauges that he's been looking for so

intently and realizes that they they have a much bigger problem on their

hands and what any of them thought he notices that on his hydraulic gauges

hydraulic quantity and hydraulic pressure across all three hydraulic

systems are at zero so he has no hydraulic pressure and no hydraulic

fluid and that means that he's not going to be able to control the plane so at

this point bill records radios Minneapolis st. Paul air traffic control

and declares emergency this time and asks for a diversion of the closest

suitable Airport and they send into Sioux City Iowa about this point in

flight back in the passenger cabin the overhead chimes ringing in Jann Brown

section Jann Brown is the one there on the far left in the turquoise suit and

she's the head flight attendant on this flight that day she looks around the

cabin she can see the rest of the flight crew nobody has their phone off the hook

she knows it's not anybody in the cabin she knows it must be from the cockpit

and she also knows that getting a call from the cockpit during the cruise

flight there's going to be nothing but bad news sure not Dudley Dvorak asked

her to report to the cockpit and she knows if she's being asked to report to

the cockpit that it's certainly not good news and telling this story later Jan

Brown says my whole world change when I open that door there was no panic but

the sense of crisis was absolutely palpable in here captain Haynes told her

we've lost all of our hydraulics we're having trouble controlling the plane

we're going to try an emergency landing in Sioux City in about 30 minutes so I

need you to prepare the cabin and brief the passengers my signal when we're

about to land will be brace brace brace and I need all the passengers in brace

position at that point Jan I don't know how this thing's going to turn out so

good luck all right so Jan brown mustard and meager thank you and then ducks into

the lavatory to compose herself before making the rounds and briefing all the

flight attendants on the plane and beginning the preparations for this

emergency landing meanwhile captain Haynes ask Dudley Dvorak to look in the

flight manual and find the procedure to handle complete hydraulic loss

the FAA mandates yeah the all our Academy so so the Federal Aviation

Administration in the u.s. mandates that any likely failure modality that's going

to strike an aircraft has to be documented in one of these checklists

you have to have a set of failure procedures for where anything goes wrong

well there's no checklist of course there's not because nobody ever expected

a dc-10 to lose all of its hydraulics and it's at this point that Minneapolis

st. Paul Center finally hands the flight over to Sioux City Iowa and captain

Haynes makes this initial contact with the tower in Sioux City ok so you know

we have all our social abilities very little elevators and also not we're all

experienced by power I mean we can only penetrate every level today and 232

heavy understand sir you can only make right turns of the hood

sounds fun done it so you to understand what Catholic means of saying there you

need to know a little bit about how airplanes are controlled he says we have

very little elevator and almost no aileron so the elevator is the control

surfaces here on the horizontal stabilizer at the back of the plane and

that controls the planes movement up and down so in saying they have no elevator

he's saying they have no ability to control their altitude

he also says they have no ailerons now ailerons are these surfaces on the back

of the wing that control roll going into turns they would use the smaller inboard

ailerons at high speed cruise and the larger outboard ailerons when they were

going slower close to the ground they had neither set so they couldn't control

the altitude of the plane they can control the roll of the plane he doesn't

say it but they don't have any rudder either so they can't control it they

can't even control the off the plane they're literally only controlling the

plane by the thrust from the two engines

well shortly after this exchange with air traffic control Jan Brown has

composed herself and she's making her way back through the first-class section

and she's briefed Jan Murray who's in the pink there on the left with her arm

in a sling and Jan Murray begins walking through the first-class cabin picking up

leftovers from lunch and starting the emergency preparations for landing when

Denny Fitch is on your right there gets her attention now Denny is another

United Airlines dc-10 pilot and he's commuting home from Denver to Chicago he

likes to say about himself that he has a radar for people in distress and that

Jan Murray was clearly in distress so he gets her attention and he says Jan don't

worry about this this thing flies fine on two engines we simply have to get to

lower altitude Jan Murray leans down so as to not be heard by overpass other

passengers and says oh no Denny the pilot and co-pilot are flat trying to

fly the plane that they've told us we've lost all our hydraulics well as a dc-10

captain Denny Fitch knows there's no way that's true

because in addition to being a dc-10 captain Danny Finch's a dc-10 check

pilot and he actually spends his days in Denver at United Airlines flight

simulation center torturing other pilots through full motion flight simulators

he's literally been through every emergency scenario that they expect to

occur on a dc-10 he's taken pilots to it to see how they react and he's never

heard of a dc-10 losing all of its hydraulics so he tells Dan Murray would

you please go let the captain know that he has a dc-10 check pilot riding back

here and I'd be happy to come up and offer any assistance that I could well

captain Haynes upon hearing this readily agrees hoping that this dc-10 check

pilot will have some magic incantation or know about some secret switch that

will fix their plane and give them control but when Fitch gets for the

cockpit he looks over Dudley Dvorak shoulder at the gauges he sees no

hydraulic quantity no hydraulic pressure he checks the busbars to make sure

there's not an electrical fault that might explain loss of flight

instrumentation there's not he knows he's never seen anything like this he

says at that point the only question I had was how long was going to take Iowa

to hit me so I've alluded to this several times but losing all hydraulics

in a dc-10 was considered an impossibility the reason for that is the

dc-10 is built with three redundant hydraulic systems one powered by each

engine and each control surface on the plane was controllable by at least two

of those hydraulic systems once more the dc-10 was one of the first generation of

aircraft along with the Boeing 747 Milwaukee 1011 Tristar that had no

manual reversion and what that means is if you're flying on say a Boeing 737 a

smaller plane you lose all your hydraulics the flight crew can still

wrestle the yokes and get some response out of the flight control surfaces be

like going down the highway and losing your power steering you can still steer

the car it's just going to be a lot more work not on the dc-10 the control

surfaces are so large and the forces acting on them are so strong that it

would be of no use to provide manual reversion you

can only move the flight control surfaces if you have hydraulic systems

so without any of their three hydraulic systems the research that had been done

indicated that one of two things would happen one the plane would go into an

uncontrollable flutter and fall of the earth like a leaf or like this plane had

tried to do it would roll over on its back and go into a descent so fast that

it would actually tear the wings off the plane before it ever got to the ground

but neither of those things happened United 232 stayed in the air at this

point since Denny Fitch didn't have any magic fixes captain Haynes asked them to

take over the throttles because it was much easier for someone to kneel down

between the two seats and control the throttles at the same time than for him

and Bill records to control the number one and number three independently and

try to coordinate their actions

meanwhile captain Haynes radios Sioux City again to reiterate the darkness of

their condition we have no hydraulic fluid which we have no elevator control

almost done and under the later on control I have serious doubts about like

a shear force it just got to some places here there that we might be all the

ditch and I don't get to throw it if I want to put it down wherever it happens

to be and then in the air traffic control audio there's this really

uncomfortable pause for Kevin Bachman tries to figure out what in the world to

tell this flight crew and he comes back with a really strong answer united 232

heavy registers pick up a road or something up there

Brooke let's go up anywhere from 2,000 feet up 15 her downhill waves

ha John can you pick up a road thanks Captain Obvious so in that bit of audio

you can hear one of the things that the flight crew is fighting about this plane

and it's called foo Boyd oscillation it's actually one of the default flight

modes of an aircraft no flight control services what happens is plane without

flight control surfaces will immediately dip into

dive and slowly it'll build air speed over the wings which will build lift and

the plane will return to an ascent and it will go up for a little bit until it

loses airspeed until it loses lift on the wings and start to descend again the

plane is trying to find equilibrium between the lift on the wings and the

gravity acting on the plane if you throw a paper airplane off of a

tall enough building you'll see it do exactly the same thing it'll flutter to

the ground going up and down at a food-grade oscillation all the way to

the ground but captain Haynes gets a crucial fact wrong in this call to Sioux

City tower he said that they were going up 2,000 feet and down 1,500 in each

wave those numbers are backwards flight 232 was actually losing about 500 feet

of altitude for every food boyd cycle that they went through you can see it

when I add that dotted line so captain captain Fitch is sitting there with the

throttles you've already heard that the plane wants to turn right so he's trying

to mitigate the plane's tendency to turn right in addition to that with just the

two throttles he has to mitigate the tendency of the plane to go into these

food oscillations try to get it to fly level because if they can't control the

fugu fugu it oscillations they have no chance of getting this thing to the

ground they will fuga way to oscillate their way straight into the earth you

can hear how well this is going in the next air traffic control transmission

with your forces now jump up and down here in at 232 I have assisted airports

about 12 o'clock and three six past okay we're time to go update I have my

club we're trying to go straight but we're not having much luck Denny Fitch

is getting the food oscillations under control but he's not having much luck

with the right turns if I show you the radar track of the flight you can see

what I'm talking about

so you can see the plane enters this chart at the bottom and it's going up

and it enters a turn towards Chicago and right at that triangle in the upper

right corner is where the fan disc on the number two engine fails and after it

fails the plane enters into a very wide sweeping turn and about the bottom of

that turn is where Denny Fitch takes over control of the plane and you see it

wanders a little bit as he tries as he figures out how to control the turning

but then as he starts to work to figure out how to control the food wide

oscillations they go into a series of very sharp right-hand turns this would

actually prove to be fortuitous because it's the only thing that allowed them

enough time to descend and to be able to land in Sioux City about this point Jann

Brown is walking from the back of the plane when a passenger told her to take

a look at the rear stabilizer this passenger had seen a big piece of metal

sticking up out the window so she looks sure enough she can see it she goes to

the cockpit she tells Dudley Dvorak the same thing

and Dvorak comes back to take a look there's a picture of this flight taken

from the ground as its approaching Sioux City Airport that you can see exactly

what they were seeing if you look closely at that rear stabilizer you can

see there's some places where daylight is peeking through where it shouldn't be

if I put a normal dc-10 tail next to it you can see a little bit more clearly

specifically this holes punched in the rear stabilizer it's missing the exhaust

exhaust cone on the engine and the plane is missing its tail cone

there's actually 70 separate pieces of shrapnel that pierced the tail section

of this plane and they all came from this an object they found in a cornfield

in Alta Iowa about three months after the crash they didn't find it intact so

you can see on the right of this disk there's clearly a crack they actually

found the two halves of the disc in separate places and they found each of

those fan blades in a separate place this had completely separated what

you're looking at here is the front intake fan of the GE CF six six turbofan

engine that powered the dc-10 if you look at an aircraft sitting on the

tarmac at any Airport and you see the fan in the front of the engine this is

that fan you can see that there's a containment ring around it but that

containment ring is designed only to contain the weight of one of those fan

blades letting go those fan blades weigh about two pounds apiece the fan disc

about 350 so there was absolutely no chance to that containment ring was

going to contain this fan disc and if you look at the placement of the engine

in the tail of a dc-10 you can see it's perfectly mounted to cause a ton of

damage to that rear stabilizer not intentionally that's where it needs to

be mounted for the aerodynamics of the plane for that engine to be efficient

but when this fan disc failed and was uncontrolled all of that fan disc went

flying through the tail of the aircraft the reason that's important is because

the tail of a dc-10 is the one place in the entire plane where all three

redundant hydraulic systems come together of course it is so when they

lost the number two engine they lost the number two hydraulic system because the

number two hydraulic pump is attached to that engine the shrapnel knocked out the

number one and number three hydraulic systems immediately after the explosion

some of the passengers on the plane reported hearing a siren like sound what

they were actually hearing was the hydraulic pumps attached to engine

number one and engine number three working as hard as they could to bring

the hydraulic system back up to pressure but actually pumping every last bit of

hydraulic fluid they had overboard

well while Dudley Dvorak is at the back of the plane looking at the stabilizer

damaged Denny Fitch finally pulls off something that they had thought was

impossible up to that point he makes a left turn this is the only left turn the

plane was going to make all day that date it was a crucial left turn they had

to turn left in order to get pointed back towards Sioux City Airport if they

missed their approach to Sioux City there was another airport anywhere

within range that they would be able to make it to so they desperately wanted to

get to Sioux City in order to attempt the landing and in congratulations

immediately after they make this left-hand turn

Kevin Bachman Bachman radios them with this in a 230 mm after one out just

slightly to your left sir tonight the trying to final and also I'll take you

away from the city whatever you do with your public money can you widen out a

little bit to the left do that do that impossible thing again for us but you

can hear the desperation and captain Haynes is voiced there he's still not

very hopeful of their journey of this day the crews still fighting to suppress

the fuga way to keep the plane lined up with the airport they're working as hard

as they can to try to bring this plane to Sioux City Iowa and you can hear the

relief in captain Haynes voice when they finally spot the airport united 232

heavy roger and a dust at the airport today the runway in sight we'll be with

you very shortly thanks a lot your help sounds pretty

really finally has a little bit of hope a few minutes later Kevin Bachman calls

back with their landing clearance which is probably my favorite air traffic

control exchange in this whole sequence k9 232 heavy the West currently 361 1

360 11 you're cleared to land on any red line you want to be bigger than I get

around Lee

so in the midst of this crazy incident I don't this is Pilate gallows humor or if

it's him actually being this controlled but he has to wear with all the crack

that's a joke with air traffic control about landing on any runway well it

turns out they actually do get lined up with the runway but it's a runway that's

been closed since World War two and it happens to have all of the emergency

equipment sitting on it and there is a runway it's closed sir that could

probably work to the south it runs a northeast to southwest pretty well lined

up on this one I think we will be fine

united 232 heavy a Roger sir that's a closed runway that'll work so we're

getting equipment off the runway and a line up for that one is it 6 to 600 feet

six thousand six hundred and the equipment's coming off so they get lined

up to runway it's a closed world war two runway it's not in great shape all the

emergency equipments on it they're in there five mile final at this point so

they're really close to the airport when they're having to scramble all of this

emergency equipment off of this closed runway to other places on the airport

now their emergency planning procedures called for them to be on this runway

because it was in proximity to the other runways at the airport it was a

convenient place to respond from so they had to try to figure out how to get out

of the way of this plane that they had no way of predicting where it was going

to go shortly after this Haines gives the

brace brace brace command and the flight attendants begin shouting brace in

unison over and over again a couple of passengers stick their head up to look

out the window to see how close they are to the ground and the flight attendants

immediately I'll get your head down

and as 232 lined up the tower got excited they were actually lined up with

a runway they were going to make the airport

Kevin Bachman at one point stood up and scream they're going to make it but then

people started noticing that 232 wasn't floating like arriving airliners

normally appeared to do it's coming in very fast

and the reason for that is because without hydraulics they had no slats or

flaps slats our flight control surfaces on the front of the wing and flaps

around the back of the wing and they extend them when the plane is flying

slow because it gives the wing more lift the plane needs that extra wing surface

when it's flying slow low to the ground in order to have enough lift to not

stall without slats or flaps if they slow down for landing they're literally

going to stall out of the skies they're not going to have enough airspeed to

make it to the ground so as a result of this 232 that day was traveling at 250

miles an hour as it came in for landing normal speed

for a dc-10 about 125 so going twice as fast as they ought to be going the sync

rate of the plane is even more alarming they're descending at 1,800 feet per

minute now the structural integrity of the landing gear was rated for 600 feet

per minute but that would have been the hardest landing you've ever experienced

a normal landing at a dc-10 was 200 to 300 feet per minute so they are

absolutely plummeting out of the sky a few minutes before they hit the ground

you can hear the ground proximity warning system tell them to pull up that

their planes in danger and captain Haynes says our luck ran out about 50

feet above the runway the plane went into one last goo-goo-eyed oscillation

and the wing dipped right right as they got to the ground and they made first

contact with the right engine may sell and it spun the plane around the impact

was hard enough that it knocked the number of the damaged number 2 engine

completely out of its mount and without that weight in the tail of the plane the

lift of the rear horizontal stabilizer was enough to pull the back of the plane

up and over in a cartwheel down the runway because of the 30 minutes advance

noticed that they had that this plane was going to crash there actually is

news footage of this plane coming in and crashing and I do have that video I'm

going to show it now I will warn you if you're squeamish you might want not want

to watch there is a good bit of fire and smoke so you can see how fast that plane

is coming in it's not floating it's coming in really quick

and somewhere behind these trees and buildings

that right wing makes the first contact with the ground and you can see it come

sliding through with fire and smoke about here you see the rear come and

cartwheel over and it continues sliding down the runway with the jet fuel

leaking out of the tanks they had they ditched as much fuel as they could but

they had to have enough to get to the ground and you can see what's remaining

in the plane catching on fire with that acrid black smoke that's rising up from

the wreckage here's the crash site they slid across the airport and ended up in

a field of soybeans that patch of concrete sits at an angle at the top of

the screen is the closed world war two runway runway 22 the plane actually hit

hard enough that it drug a six-foot ditch in that runway with its landing

gear just tore the concrete right out of the ground

Kevin Bachman at this point left the control tower to weep because he had

just watched the crash and he knew everybody had died because how could

anybody live through that but his rescuers arrived at the plane a strange

things started to happen people started to emerge from the wreckage some of them

without a scratch there's a story of one passenger who was walking away from the

plane seemingly on her turned around walked back to the wreckage got his

suitcase and they would later find him in the airport bar drinking a glass of

whiskey so 232 was still absolutely a tragedy 111 people died that day but of

296 people on board a hundred and eighty five of them survived now there's a bit

of context I need to give you so you can understand the significance of that 185

number up until this point in the previous 25 years of commercial aviation

no one had ever survived the complete loss of flight controls of an airliner

nobody 185 survived this day the National Transportation Safety Board is

the the US government body that investigates plane crashes

there's a telling line in their report as well they say the Safety Board

believes that under the circumstances the United flight crew performance was

highly commendable and greatly exceeded reasonable expectations reasonable

expectations this day would have been nobody surviving the NTSB in the process

of developing their report did extensive simulator exercises they configured

dc-10s and simulators for exactly the flight conditions at 232 fat-faced that

day very few flight crews they put through

the simulator exercise got the plane anywhere close to the airport nobody was

successful as this crew it's how they do it what made this flight crew different

let me let captain Haynes tell you himself

in a speech that he gave at NASA's Ames Research Facility the preparation that

paid off for the crew was something that United Airlines started in 1980 called

cockpit resource management up until 1980 we kind of worked on the concept

that the captain was the the authority of the aircraft whatever he said goes

and we've lost a few airplanes because of that we had 103 years of flying

experience up there in the cockpit trying to get that airplane on the

ground not one minute of which we had actually practiced any one of us so why

would I know more about getting that airplane on the ground under those

conditions than the other three so if I had not used CLR if we had not let

everybody put their input in it's essentially wouldn't emit so what

captain Haynes is talking about there is modernly referred to as crew or cockpit

resource management and it's focused on the human dynamics of the cockpit a

United 232 is actually considered one of the first big success cases of crew

resource management it's focused on interpersonal communication leadership

and decision-making it's actually based on research that was done by NASA's Ames

Research Center so it's interesting that that's where he was giving this the

speech there were a couple of crashes were stubborn captain's not listening to

their flight crews had caused tiny problems turn into big disasters one of

the most notable was United flight 173 that cry

outside of Portland Oregon and what the crew was facing that day was an

indicator indicator that told them that one of their landing gear was not down

now it turned out their gear was down the whole time it was a faulty switch in

the wheel well but they spent so much time flying around trying to

troubleshoot the problem and despite the urgings of the copilot and the flight

engineer that they were about out of fuel and they should return to the

airport they crashed four miles short of the airport because the captain wouldn't

listen he was insistent there was landing your problem and they needed to

fix it there's a couple of tenets of crew resource management that are very

relevant to how we spend our days as software engineering leaders first of

which is no heroes see cockpit resource management emphasizes cooperation over

heroics one of the things that struck me as I was doing the research for this

talk is captain Haynes deliberately uses the word we' when he's talking about the

sequence of events he says things like we were at 38 degrees of bank and

increasing so we closed the number-1 throttle and firewall the number three

now he uses the word we there to talk about the moment that he captain Haynes

saved flight 232 he lets Denny Fitch stay on the throttles long after it's

obvious that that's all that's controlling the plane it'd have been

really easy for him to go okay this is the only control we got then he get out

of the way it's my ship but instead he recognized that Dennis Fitch had been

sitting at the throttle long enough and had developed that rhythm I had

developed an intuitive understanding of how the airplane was operating under

these conditions and that it was best to let Denny Fitch continue to do that job

rather than him asserting his authority as the captain of the plane now do we do

that as soccer leaders we need to encourage our teams to work together to

find solutions to hard problems and we need to sell like celebrate success as a

team and learn from failure as a team as well we shouldn't look for individual

heroes and individual scapegoats we should live as a team and die as a team

one of the best ways to do that is to make sure that everyone has a voice you

heard captain Haynes say it if everyone on the plane hadn't had input it's a

cinch we wouldn't have made it it's an obvious clear connection to Soph

or teams here as leaders we desperately have to avoid allowing our teams to

develop dominant voices we especially have to make sure those dominant voices

are in our own because it's really easy to get into that cycle it's really easy

to forget as either an explicit or implicit leader on your team the weight

that your comments have you can guide your team's effectively because of the

authority that your voice carries but it's a double-edged sword you can also

create conditions where you're the only voice that's guiding your team and other

people are afraid to have input this is especially true with new engineers you

need to give new engineers space to develop their identity and software to

assert their their growing authority and to make the mistakes they need to make

to learn and grow if there's only one dominant voice and it's constantly

correcting new engineers on the team they're never going to make the mistakes

that they need to make in order to learn the lessons they have to learn it's also

essential if you're building a diverse team and you absolutely should be

because of the diversity of perspective and expertise that it brings to your

team but if you allow dominant voices to take over the conversation of your teams

you'll find it very hard to subtract and keep diverse talent on your team because

voices that are used to being marginalized will pick up on that

pattern very quickly and they won't hang around to give you the benefit of the

doubt and see how it's going to turn out so if you want to build diversity on

your teams you have to make sure that everybody on your team has a voice you

have to cultivate that team culture what are the interesting things about cockpit

resource management is that the captain is still the captain every decision

that's made in the cockpit still comes down to him so as a team lead you do

still have authority but in cockpit resource management the captain's job is

to ensure that he uses his authority to make sure that every voice on the

cockpit is heard everybody has input that he's heard every idea available

without that it's really doubtful that this crew could have gotten this outcome

out of United flight 232 they wouldn't have made it to Sioux City Airport they

wouldn't have gotten to the first responders who got every survivor to the

hospital in under 45 min they would have been crashed in the

middle of a cornfield somewhere in Iowa and it would've taken the response much

longer and the outcome that they would have been far different so remember that

software is a team sport building software takes technical skill but

building the right software takes human interaction and lots of it so make sure

you're building that kind of culture on your team a lot of our teams tend to

look like those flight crews that brought planes down let's work together

to look more like the crew of flight 232 if we do that if we focus on building

that kind of culture on our teams we will do amazing things together thank

you