The LAST Airliner To Ever Attempt THIS! | Southern Airways 242

0:00 It is midafter afternoon on April 4th, 1977 in Huntsville, Alabama.

0:06 Around its airport terminal,

0:08 everything is following the normal routine with bags

0:11 and carts rolling over the wet pavement,

0:13 passengers hustling through the terminal,

0:15 and a tug idling impatiently in front of the nose gear of a humble DC9,

0:20 which is getting ready to depart.

0:23 Rain has already started falling and the sky shows that flat

0:27 and washed out look that it gets when thunderstorms are nearby.

0:31 But beyond the airport area, something is now brewing.

0:36 Across Alabama and Georgia,

0:38 the afternoon weather is about to develop into something truly violent.

0:42 And the pilots of Southern Airways Flight 242

0:45 are about to find this out the hard way.

0:49 Flight 242 arrived to Huntsville after a brief hop from Muscle Shaws,

0:53 Alabama, and was now preparing for a very quick turnaround.

0:57 The coming flight was one of those legs

0:59 that on paper didn't look very complicated at all.

1:03 It was supposed to be just a short hop from Huntsville over to Atlanta,

1:07 and it was planned to last only about 25 minutes or so.

1:11 The planned cruise altitude was therefore also quite low, only 17,000 ft.

1:16 And the flight's routing ran straight from the Huntsville

1:18 departure towards a VUR beacon called Rome, which would then lead them

1:23 in towards Atlanta's Hartfield Jackson International Airport.

1:27 In an operation built around quick flights and tight schedules,

1:31 this flight was pretty standard for Southern Airways, though.

1:34 One more turnaround in a day full of similar ones, where the airplane arrived,

1:39 swapped passengers, and was then expected to move again as soon as possible.

1:43 And that pace was exactly what defined this stop in Huntsville.

1:47 The DC9 would only be at the gate

1:50 for around 10 minutes with passengers getting off,

1:53 getting on, bags shifted, paperwork quickly updated, and then closing the doors.

1:58 So, the crew therefore had to compress their checks and procedures

2:01 into a time span allowing all the things that were strictly required.

2:06 The two pilots in the cockpit were also running on the edge of their rest

2:09 limits and now had to skip lunch after having been on duty for over 7 hours.

2:15 So instead, they now used what few minutes they had to set up the cockpit,

2:20 conduct takeoff and on route briefings and build a mental

2:23 model of the short flight that they had ahead of them.

2:25 But at Southern Airways, this was pretty much standard practice.

2:29 The captain, who was 54 years old at the time,

2:32 had logged around 19,000 total hours, including roughly 3,200 hours on the DC9.

2:38 And his first officer, who was 34 years old, had around 3,900 hours,

2:43 but he was much less experienced on the type

2:46 with only around 235 hours on it so far.

2:50 Joining them for this flight would be 81 passengers as well as two cabin crew,

2:54 bringing the total number of souls on board up to 85.

2:58 The aircraft that they would soon be operating was a shiny

3:01 Macdonald Douglas DC931 with registration November 1335 uniform and it

3:08 was powered by two Pretton Whitney JTA Delta 7 Alpha

3:11 engines who will soon play a major role in this story.

3:16 Now, as the pilots were getting ready,

3:18 the weather outside was slowly starting to turn to the worse.

3:21 By time 1533, the airport was reporting

3:24 thunderstorms and moderate rain showers with a broken

3:27 ceiling of around 800 ft and with winds blowing at about 16 knots.

3:32 Now, these were still okay conditions for the upcoming flight as long

3:36 as the pilots made sure to stay clear of those thunderstorms.

3:40 I have actually flown in very similar weather myself many times.

3:44 And when you face weather like this, as long

3:46 as you have the correct weather information and stay vigilant,

3:49 it should be relatively easy to manage.

3:53 But the problem on this day wasn't

3:55 actually the weather at Huntsville Airport itself.

3:58 No, it would instead be the convective system that was evolving quickly

4:02 across the surrounding region and was

4:05 about to turn into something truly violent.

4:08 At the time Flight 242 was getting ready for departure,

4:11 severe weather conditions were already being observed across the region,

4:15 and they were worsening quickly.

4:18 Over the course of the afternoon, roughly 20 tornadoes had been confirmed

4:22 to have touched down across Alabama and Georgia.

4:24 And one had even been reported near Rome,

4:27 Georgia, right on Flight 242's planned route.

4:31 Now, none of that had happened suddenly

4:33 or in a way that nobody could have predicted.

4:36 The National Weather Service had actually begun publicizing

4:39 the severity of this situation in a series

4:41 of tornado watches and SIGATs nearly 3

4:45 hours before flight 242 was to leave Huntsville.

4:48 In fact, information about this had already been included in the paperwork given

4:52 to the flight crew before they

4:54 had left their previous destination, Muscle Scholes.

4:58 But warnings on paper sometimes doesn't have the same effect

5:01 on pilot situational awareness like a realtime weather map does.

5:05 Especially since thunderstorms and the dangers that they come with is

5:09 often highly localized and can most of the time be easily avoided.

5:13 Also back in 1977 there was no cockpit

5:17 satellite weather or iPads with live weather displays.

5:20 So getting realtime severe weather information into the cockpit depended

5:24 on a chain where weather services had to first disseminate it.

5:29 The airline had to subscribe to that service, distribute it,

5:32 and then finally the crew had to actually see and brief it.

5:36 The National Weather Services most direct realtime product back

5:40 then was a narrative warning system called RA AWC,

5:46 which was a stream of realtime reports

5:48 and coordination messages intended specifically to keep subscribers

5:52 aware of rapidly changing weather radar and warning

5:55 information which Sudden Airways hadn't subscribed to.

6:01 But they did have access to another system,

6:03 a radar product rooted through the weather

6:06 bureau called the radar remote system or WBRR,

6:11 and it produced frequent printouts of regional radar displays

6:15 and then transmitted them by fax to their subscribers.

6:19 In theory, this gave the airline briefing

6:21 office something close to a semi-live radar picture

6:25 since it was updated often enough that dispatchers

6:28 could see where the severe weather was forming,

6:30 intensifying, and how fast it was moving.

6:34 But when the pilots of flight 242 stopped in Huntsville,

6:37 the fax machine at the local Southern Airways office wasn't working.

6:42 So, their dispatchers weren't able to include any of these radar

6:45 printouts in the information pack that was given to them.

6:49 Then 9 minutes before departure, a Southern Airways dispatcher tried to call

6:54 the National Weather Service office in Athens,

6:56 Georgia to get updated information, but the line was busy.

7:00 So he soon gave up and instead the crew were

7:03 just given the latest meta observations from some on route airport.

7:08 This meant that the pilots of flight 242 were now only

7:11 equipped with some segments and reports that were several hours old,

7:15 as well as a set of weather observations from airports along the route,

7:18 which provided only snapshots of the conditions

7:20 at those specific times and locations,

7:23 which was obviously completely inadequate.

7:27 And this is probably the part that can be

7:29 a little bit hard to appreciate from the outside.

7:32 You see, a flight crew can do everything

7:34 procedurally correct and still be operating with a dangerously

7:38 incomplete picture of the actual weather situation unless

7:42 they speak up and ask for more information.

7:46 But a 10-minute turnaround will mean that there will

7:49 be precious little time to actually evaluate the weather properly.

7:52 So, a tight turnaround like that will

7:55 increase the chance of something being missed.

7:58 In any case, with the cabin soon closed up,

8:01 flight 242 left the gate and started taxiing

8:03 out of the tarmac and into the rain.

8:06 Now, the captain would be acting as pilot monitoring

8:08 and the first officer would be pilot flying for this short leg.

8:11 And eventually, the sleek DC9 lined up for departure.

8:16 From the cockpit, the weather ahead looked quite manageable,

8:19 something that the pilots should be easily able to thread their way

8:23 through using their weather radar and support from air traffic control.

8:27 So at time 1554 local,

8:30 the DC9 lifted off the runway at Huntsville and started climbing into the rain.

8:35 Immediately after takeoff, the captain began monitoring his weather radar,

8:38 looking for a safe passage forward, but all it showed at that point was rain.

8:43 So he now told the first officer, "The radar is full of it.

8:47 Take your pick." A moment later,

8:49 Huntsville departure control called up and said, "Sudden 242.

8:53 I'm painting a line of weather which appears to be

8:56 moderate to possibly heavy precipitation starting about five miles ahead.

9:01 And in response to that, the captain responded,

9:04 "Okay, we're in the rain right now.

9:07 It doesn't look much heavier than what we're in right now,

9:09 does it?" "Uh, it's a solid mass.

9:14 It appears to be a little bit heavier

9:16 than what you're in right now," responded the controller.

9:19 And that caused both the pilots to now

9:21 look a little bit closer at their weather radar.

9:24 Now, the radar on the DC9 was a fairly basic device

9:27 with a black and white display called a Bendix RDR1 Echo.

9:32 Its screen was only around 5 cm across.

9:35 So, it was nothing like the kind of color displays that we have today,

9:38 which shows storms in neat bands of green, yellow, and red.

9:43 Now, on the Bendix, precipitation would show

9:46 up as white static against a black background.

9:49 And if you wanted any sense of intensity,

9:51 you had to then change the radar into something called contour mode.

9:56 With that, the worst precipitation was identified

9:58 as a dark hole inside the block of white static,

10:02 creating a white contour surrounding a black void.

10:06 But the trouble was that those contour

10:08 holes were the same color as the background.

10:10 So this meant that a clear gap in the weather and the strongest

10:15 core of a storm could look at a glance very very similar.

10:21 Now these pilots had experience with this radar and they knew its quirks,

10:24 but it was still a system that needed to be

10:27 interpreted instead of just showing the pilots what was going on.

10:31 And on top of that, the radar also operated

10:34 in a part of the radio spectrum called the Xband,

10:37 which covers relatively high frequencies and short wavelengths.

10:41 And this meant that it was especially

10:43 vulnerable to a phenomenon known as attinuation.

10:47 So what's that then?

10:49 Well, basically this type of weather radar

10:51 worked by bouncing radio waves off precipitation

10:54 and then measuring how much of the signal that made it back to the receiver.

10:59 The stronger the returning signal, the heavier the precipitation.

11:03 But if the airplane was already in or very near heavy precipitation,

11:08 well then so much of the signal would be reflected

11:10 back that the radar waves never reached any precipitation further ahead,

11:15 causing those areas to read as clear air,

11:18 but only a faint haze shown on the radar closest to the antenna.

11:23 And the practical result of this shortcoming was that it

11:26 could become entirely impossible to determine what was a contour hall,

11:31 a radar shadow caused by signal attenuation,

11:35 or what was actually just clear air.

11:37 It would all just show up as a mess

11:39 of confusing black and white nonsense on the screen.

11:42 And what that meant for this story was that as flight

11:45 242 now climbed out of Huntsville through the cloud and rain,

11:48 the radar picture that they were using was likely being distorted in this way.

11:53 at exactly the time they needed it the most.

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13:29 Now, let's get back to the video.

13:32 In any case, the captain now thanked the controller for the help,

13:35 but at the same time, the confusion about what they actually had

13:37 ahead of them had not gotten much better.

13:41 The first officer now added, "I can't read that.

13:44 It just looked like rain.

13:46 What do you think?

13:47 There's a hole?" And the captain answered by saying,

13:50 "There's a hole right there.

13:52 That's all I see." Now, this search for a hole in a line

13:56 of severe thunderstorms was actually quite risky business,

14:00 especially when relying on such a primitive weather radar.

14:04 There are circumstances where there simply isn't

14:06 any safe way through a line of thunderstorms,

14:09 in which case the only thing that you can do

14:10 is to divert and await the score line to pass.

14:14 But, of course, that's easy to say.

14:16 Thunderstorms was and still is a very common occurrence around this area.

14:21 And these pilots had just flown through this very weather

14:24 just an hour or so earlier with no real issues.

14:28 So they likely now figured that it wouldn't be much

14:31 worse on this leg and they had a schedule to keep.

14:36 Getitis is a very powerful thing.

14:39 And if you combine it with a low

14:40 cruise altitude where you're basically constantly inside of clouds,

14:44 bad weather, and a primitive weather radar,

14:47 you'll have quite a dangerous mix as we will soon see.

14:51 Now, before we continue,

14:52 it's probably worth stopping here and explain a bit more about

14:55 the type of weather that this aircraft was now about to pass through.

14:58 You see, severe thunderstorms isn't just slightly more intense rain showers.

15:04 No, they are actually completely contained local weather systems built

15:08 around some very violent vertical motions in the air inside.

15:13 They can be created by, for example,

15:15 quickly rising moist air in an unstable air mass or by the heavy cold air

15:20 from a cold front lifting up the warm and moist air in front of it,

15:24 quickly cooling it down and therefore releasing its energy.

15:27 You can always recognize these storms by their dark appearance at the base,

15:32 their extreme heights,

15:33 which can reach well above most aircraft maximum service ceilings,

15:37 and their fussy diffuse white anvils at the top.

15:42 Now, thunderstorms that are created by local air pockets are often very local.

15:47 But storms created by cold fronts, like in this case,

15:50 can be massive and also create something known as squala lines,

15:54 which are literal walls of cells that can continue for hundreds of miles.

15:59 And no matter how they are formed,

16:01 the air inside of these cells is constantly moving up and down,

16:04 bringing anything inside with it.

16:07 For an aircraft, this often means severe or even extreme turbulence,

16:10 where the storm's updraft and downdrafts causes sharp and unpredictable changes

16:15 in the vertical wind that can load and unload the wings in seconds.

16:19 So, even if an airplane caught inside

16:21 of a cell like this stays within its structural limits,

16:25 its passengers and crew can still be violently thrown into ceilings,

16:28 bins can open and spill its contents,

16:30 and anyone who is not properly strapped in can be seriously injured.

16:35 On top of this, these air movements

16:37 can also cause rapid air speed changes leading

16:39 to over speeds or stalls or in extreme

16:42 cases even force the aircraft into the ground.

16:45 And the powerful updrafts often create large

16:48 hailstones that can crack or shatter outer windshield panes as well as dent

16:52 or destroy fragile composite components and leading edges.

16:57 Now, these type of violent thunderstorms can obviously occur anywhere,

17:01 but in the southern and central United States,

17:03 where warm, moisture richch air from the Gulf

17:05 of Mexico regularly meets the colder, drier air from the north and west,

17:09 this often creates exactly the kind of instability

17:12 needed to power truly extreme storms and score lines.

17:17 Now, all of that is of course well known and even back

17:20 then pilots were taught to never try and fly through convective cells,

17:24 but instead give them at least five nautical miles

17:26 of lateral clearance and ideally 20 m if possible.

17:31 Those kind of margins are needed because the dangers

17:33 from these storms doesn't just end outside of the cloud itself.

17:37 It can actually throw hazards outward and far beyond its visceral position.

17:42 Anyway, by time 1557, the weather ahead had stopped looking like a scattered

17:47 nuisance and instead now looked like a single continuous problem.

17:51 On the frequency, the controller's tone still stayed calm,

17:54 but the message changed a bit when he said,

17:57 "You're in what appears to be about the heaviest part of it now.

18:01 What are your flight conditions?" The captain

18:05 answered and explained that they were

18:06 experiencing light turbulence and what sounded

18:09 at least for the moment like moderate rain.

18:12 And the controller replied that based on his radar depiction,

18:16 it didn't look like it would get any worse.

18:18 And he then handed them over to the next controller at Memphis Center.

18:23 Now, in the cockpit,

18:24 that last statement from the controller was likely interpreted as reassurance.

18:28 And it also fit the picture that the crew

18:31 had built up that the weather head was not great, but not terrible either.

18:37 The captain could now be heard saying, "As long as it doesn't get any heavier,

18:41 we'll be all right." And the first officer agreed,

18:45 but as they penetrated deeper into the storm,

18:49 the captain soon added, "Here we go.

18:52 Hold them, cowboy." And a couple of minutes later, he added,

18:55 "I think we better slow it up here

18:57 in this crap." To which the first officer replied,

19:00 "Got you covered." So he now reduced the speed

19:04 to the turbulence penetration air speed of 285

19:07 knots in an effort to dampen the effects

19:09 of the turbulence that they were obviously experiencing.

19:13 A few minutes later, the DC9 reached its planned cruise altitude of 17,000 ft.

19:18 But instead of the weather easing off, the cells ahead now just kept building.

19:24 The captain continued looking down at his radar picture and said, "Looks heavy.

19:29 Nothing's going through that." But remember, on their primitive weather display,

19:34 the difference between a possible route and the potentially

19:38 dangerous trap could be only a few pixels of contrast.

19:43 "That's a hole, isn't it?" the first officer asked,

19:46 still looking for a possible path forward between the cells.

19:49 The captain hesitated.

19:51 Uh, it's not showing a hole, is it?

19:55 By now, the soundscape in the cockpit had also started changing.

19:59 The moderate rain that had previously sounded like a hiss had now become a roar,

20:03 and it then changed into something else completely,

20:06 as the CVR started picking up sharp

20:09 thuds that definitely didn't sound like water anymore.

20:13 The captain now ordered the first officer to handfly at about 285

20:17 knots as a hail storm now started impacting the aircraft with full force.

20:22 It started as individual thumbs and strikes,

20:25 but it then turned into a continuous hammering that rattled the entire fuselage.

20:30 So in only a matter of seconds,

20:33 the pilots had now moved from watching the weather returns

20:35 on their weather radar to being fully and truly inside of it.

20:40 The first officer now asked, "Which way do we go?

20:43 Cross here or go out?

20:45 I don't know how we get through here." And unbeknownst to either of them,

20:49 the storm that they had just flown into was now all

20:53 around them and also extended tens of thousands of feet above them.

20:57 So there was no obvious way out.

20:59 They were trapped.

21:02 Nevertheless, they now tried forcing through it because that's what you

21:05 do when you're still convinced that there is a route out.

21:09 Modern procedures today give guidance to immediately consider a 180

21:13 degree turn to quickly get back out again whilst also maintaining

21:17 turbulence penetration speed and increasing the lighting inside of the cockpit

21:21 in order to counteract any blinding effects from lightning strikes.

21:25 But that's not what now happened.

21:28 The captain instead started shouting out fragments of sentences,

21:31 pointing with words to a picture and a plan that only they could see.

21:36 I know.

21:37 You're just going to have to go go out.

21:40 And the first officer answered, "Yeah,

21:42 right across that band." To which the captain returned,

21:45 "All clear left approximately right now.

21:48 I think we can cut across there now." And the first officer replied,

21:52 "All right, here we go." As they pushed deeper into the storm,

21:58 the hail intensified again with hailstones that witnesses

22:01 later described as the size of tennis balls.

22:04 And just as they were going through this, air traffic control,

22:07 who of course had no idea of how bad things were now getting,

22:10 gave them a new clearance.

22:13 Sudden 242 descend and maintain 14,000.

22:18 This meant that the flight had already reached its planned top of descent.

22:22 So the controller was now facilitating their descent down towards Atlanta.

22:27 In the cabin, the cabin crew had been able

22:29 to feel the situation even without having access to any instruments.

22:33 The sound of hail pelting the aircraft

22:36 together with the turbulence and the general

22:38 darkness inside of the cloud would have given all of the hints that they needed.

22:44 So, one of the flight attendants now picked up the PA

22:47 handset and told the passengers to keep their seat belts fastened,

22:50 to relax, and that they should be out of this shortly.

22:54 She was doing that in a very steady and calming voice,

22:57 effectively doing the job that the pilots weren't

22:59 in a position to do at that point,

23:02 keeping the 81 passengers from panicking in a situation that would

23:05 have been truly scary and was about to get way worse.

23:11 Meanwhile, in the cockpit, after acknowledging the descent clearance,

23:15 the pilots pulled the trust levers back all the way back

23:17 to idle and then began to descend through the heart of the precipitation.

23:22 And before we get to what happens next,

23:24 I just want to talk a little bit about how jet engines work and the multitude

23:29 of things that can happen if they start ingesting a lot of water and hail.

23:34 You see, a jet engine functions by keeping

23:37 a steady stream of air moving through its core.

23:41 The compressor stages at the front pull

23:43 in squeezes and accelerate the air before it's

23:46 mixed with fuel in the combustion chamber

23:48 and then ignited to produce hot expanding exhaust gases.

23:54 Those then spins the turbine stages before

23:56 they escape at the back of the engine.

23:58 And the turbine in turn powers the compressors and the fan

24:02 in the front allowing the engine to effectively sustain itself in a loop.

24:07 You can think about it like a balloon you have released

24:09 to let the air flow out which then keeps filling itself up.

24:13 Now the massive fan in the front actually produces the majority

24:16 of the engine thrust together with the hot exhaust gases in the back.

24:21 But it's the core that provides the energy that keeps the whole machine turning.

24:26 The problem though is that when a jet

24:29 engine starts ingesting large amounts of water and hail,

24:32 some of the energy that would have normally gone into spinning

24:35 the turbine gets diverted into changing the state of that water into steam,

24:40 which lowers the flame temperature in the combustion chamber.

24:44 So this means that as the water to air ratio rises,

24:47 the temperatures that the fuel is able to produce decreases,

24:51 which then in turn decreases the effect

24:53 of the expanding gases driving the turbines.

24:56 So given a constant thrust setting, as the rain gets more intense,

25:00 the engine will also produce less compressor pressure,

25:03 less fan speed, and less thrust.

25:07 Now, this is normally very manageable and engine makers like Breton Whitney has

25:11 built in plenty of margin since obviously flying through rain is to be expected.

25:17 But if the water ingestion becomes extreme enough,

25:21 the core can be driven down towards conditions that are below

25:24 idle thrust simply because the amount of fuel required to keep it

25:28 stable under that water load exceeds what the fuel control system

25:32 can deliver and therefore also exceeds what the combustion process can sustain.

25:37 And eventually if the conditions for stable combustion can't be maintained,

25:42 well then the combustion will cease and the engines will simply flame out.

25:48 That danger then also becomes much worse at lower

25:51 power settings because of something known as the scoop factor.

25:57 You see, an engine inlet doesn't just take air in.

26:00 It actually scoops a column of air proportional

26:03 to the airplane's forward speed and the inlet's physical size.

26:08 At higher thrust settings, the engine draws most of that air through

26:12 the core and bypass ducks because it actually needs it.

26:15 But at idle thrust, the core air flow is reduced.

26:19 So the engine then simply doesn't need

26:22 to and in fact cannot swallow the full amount

26:24 of air that the forward motion of the plane is trying to ram through its inlet.

26:29 This means that the inlet flow of air will adjust so that some

26:33 of the air will be deflected around the engine instead of going inside of it.

26:37 And that works perfectly well for air since it has very low inertia.

26:44 But water droplets or hailstones have much greater

26:47 inertia and won't get pushed aside nearly as easily.

26:51 Which means that even as air flow through the core decreases,

26:54 the amount of water being ingested remains largely the same.

26:58 Or in other words, there will be much less air but nearly the same

27:02 amount of water or hail leading to a rapidly rising water to air ratio.

27:09 And at the same time, another thing also happens at lower fan

27:12 speeds that makes this situation even worse.

27:15 You see, when the fan is spinning fast, it will act like kind of a shield,

27:19 centrifugating a lot of water outwards into the engine bypass flow.

27:24 But when it's spinning slower, more of those droplets will make it in between

27:29 the blades and then continue deeper into the engine.

27:32 So all of this combined means that in very heavy precipitation,

27:36 a lower trust setting that also reduces core air flow also

27:41 increases the concentration of water reaching the core in the first place.

27:45 That higher water to air ratio then

27:47 combines with the already lower thrust output at idle and it becomes much easier

27:52 to overwhelm the engine's ability to keep running.

27:56 That's why the most dangerous place to be in a situation

27:58 like this is not cruising through heavy rain and hail,

28:02 but instead descending at relatively high forward

28:05 air speed with the thrust levers pulled back,

28:08 which is exactly what flight 242 was now doing.

28:12 descending through a biblical rain and hail storm at a high

28:16 forward air speed and with the engines at idle.

28:20 This meant that as flight 242's engines now ingested more and more water,

28:25 the turbine rotation speed soon started

28:27 falling far enough that the engine-driven

28:29 generators could no longer stay online and continue producing electrical power.

28:35 And that meant that suddenly the cockpit

28:37 and cabin lost all normal electrical power.

28:40 The instrument lighting in the cockpit now went dark

28:43 together with several other systems including the cockpit voice recorder.

28:46 And in the cabin, the normal light now suddenly dropped out.

28:50 So for the passengers,

28:51 it would have felt like the airplane had suddenly been switched off mean air.

28:55 And for the pilots up in the front,

28:56 the total loss of electrical power whilst in the middle of a thunderstorm

29:00 fighting against severe hail and turbulence must have been equally terrifying.

29:06 Now, that blackout lasted for 36 seconds, and when the power came back,

29:10 it likely did so because the thrust levers had been pushed

29:13 forward enough to bring the generators back into the working range.

29:17 When the cockpit voice recorder came back online,

29:20 the first thing that it captured was

29:21 the first officer calling out, "Got it back.

29:24 Got it back." During that blackout, the radios had also gone dead,

29:28 and air traffic control had tried several times to call them.

29:32 Only now on the fifth attempt did they get through

29:35 and controller proceeded with a request for the flight to climb

29:39 back from 14,000 ft up to 15,000 ft in order

29:42 to provide separation from some other traffic in the area.

29:46 The captain quickly acknowledged this and told the controller

29:49 that uh they were trying to get it up there.

29:52 Meanwhile, hail continued to smash into the windscreen,

29:55 and soon spiderw webs of cracks began to form on its outer pane,

30:00 making it almost impossible to see through.

30:03 But worse, what no one knew at this point was that inside of the engines,

30:07 the delicate balance of temperatures and pressures was now changing,

30:11 and not in a good way.

30:13 You see the high-pressure compressor stages operate

30:16 within a specific range of conditions defined

30:19 on one hand by airflow mass and on the other by the pressure ratio.

30:24 That is the pressure at the back end

30:27 of the compressor divided by the pressure at the front.

30:30 The more lopsided this ratio gets,

30:33 the closer the engine will get to an imaginary boundary called the surge line,

30:38 which is the point at which the smooth

30:40 front to back air flow through the core collapses.

30:44 And what does that mean then?

30:47 Well, basically the evaporated water will cool the air

30:50 as it exits the high-pressure compressor and enters the combustion chamber.

30:55 And as that cooled flow loses energy,

30:57 it also slows down and begins to stack up instead of moving cleanly backwards.

31:04 This then in turn causes an increase in pressure near the back

31:07 end of the high-pressure compressor leading to a higher pressure ratio.

31:12 And when that ratio exceeds the surge line,

31:15 air will begin forcing its way forward,

31:18 seeking equilibrium with the lower pressures closer to the inlet.

31:22 And this reversal of air flow marks the onset

31:25 of something that we call a compressor surge or compressor stall.

31:30 Now these stalls tends to happen in a cyclical

31:33 periodic way where air flow breaks down, reverses,

31:37 then reestablish itself and then breaks down again

31:40 and with each cycle hammering the engine harder than the last.

31:45 So by this point, the DC9's engines

31:47 were already operating very close to that surge

31:50 line as the vast quantity of rain and hail continued to be ingested.

31:55 Then during the blackout, the first officer likely increased thrust slightly

32:00 in response to the decreasing engine RPM,

32:02 which was ultimately what restored the electrical power.

32:07 But that also pushed the operating pressure ratio past the surge line,

32:12 causing the engines to start surging.

32:15 Now all pilots are taught to recover from an engine

32:18 surge by reducing thrust immediately to let the compressor recover.

32:22 But amid this chaos that they were now

32:25 in with the turbulence and their windshield cracking,

32:28 the pilots seem to be unaware of the surging as it started.

32:33 And remember that request from air traffic control to climb.

32:37 Yeah.

32:38 When flight 242 was asked to climb back to 15,000 ft,

32:42 the first officer advanced the trust lever at exactly the wrong time.

32:47 With the engines already surging,

32:48 the increased fuel flow and suddenly higher thrust demand

32:52 now took the situation from bad to truly catastrophic.

32:56 The violence of the surges immediately greatly increased,

33:00 producing sharp internal pressure spikes that were

33:03 soon so powerful that they forced the sixstage blades of the low pressure

33:07 compressor forward into the fifth stage stator veins.

33:12 That then caused the blades and the veins to disintegrate,

33:16 sending those pieces tumbling deeper into the engine core.

33:20 And once they reached the high-pressure compressor,

33:23 the damage multiplied and turned what had started as an unstable

33:27 air flow problem into a cascading collapse of the entire compressor system.

33:33 On top of that, with the air

33:35 flow now disrupted and compressor efficiency degraded,

33:38 the additional fuel injected with the first officer pushed the thrust levels

33:41 forward now also cause the temperatures in the engines to rapidly rise,

33:46 leading to catastrophic overheating.

33:49 aluminium components in the compressor sections began to melt

33:53 and molten slag was then sprayed through the compressor system.

33:57 So all in all, within roughly a minute,

34:00 both engines now completely failed with internal damages

34:03 so severe that restarting them would prove impossible.

34:08 In the cockpit, the indications of this now came in quick succession.

34:13 First, it was noticed as an abnormal throttle response

34:16 and then the total failure of the left engine.

34:20 The first officer called out that one engine would not spool properly

34:23 while the captain reported to ATC that they had lost an engine.

34:28 And that was then followed up just moments later of him adding,

34:31 "The other engine is going too." To which the controller just responded,

34:37 "Say again." And to that, the now flustered captain transmitted,

34:41 "We lost both engines.

34:43 Get us a vector to a clear area." Now, when he heard this, the controller took

34:48 their latest location and suggested that they should contact

34:50 Atlanta approach for vectors to Dobins Air Force

34:53 Base that was located just northwest of Metro Atlanta.

34:58 The first officer mentioned to the captain that that's

35:00 where he had performed some of his military training,

35:03 and he also added, "Tell them to give me a vector

35:05 to do if they're clear." But just a few seconds later,

35:09 as the pilots tried desperately to relight at least one of their engines,

35:13 the battered engine cores slowed down below

35:16 the threshold needed to power the plane's generators.

35:19 And the DC9 again went dark, vanishing from radar and radio contact.

35:26 And this time, the blackout would last just over 2 minutes,

35:30 just as the pilots needed vectoring and help the most.

35:35 This was now turning into a real nightmare with the pilots facing the total loss

35:39 of both engines below 15,000 ft inside

35:42 of a torrential thunderstorm and with a crackulated windshield.

35:47 The first officer was now hand flying the plane.

35:49 And back in those days,

35:51 there was no real procedure or training for responding to a dual engine failure.

35:56 That was because up until that point,

35:58 the possibility of that happening was seen as so

36:00 remote that it wasn't worth even taking into consideration.

36:05 But on board flight 242, that improbable scenario was now very real.

36:11 And with just minutes before their powerless plane would hit the ground,

36:14 the pilots had now very little time to prepare for an emergency landing.

36:19 And to make matters even worse, while they were under total blackout conditions,

36:24 the crew had performed a 180°ree turn to the west northwest,

36:28 taking them away from Atlanta and from Dobbins.

36:32 Now, because the CVR had stopped recording during that power cut,

36:36 we will never know for sure why they did

36:38 this, but it might have been because they saw

36:40 clear air in that direction and just wanted to try

36:44 to escape from the storm by any means possible.

36:47 Regardless of why, this simple action would

36:50 now have grave consequences because by the time that they managed to start up

36:54 the auxiliary power unit and restore electrical power,

36:58 they were now down to only 7,000 ft

37:00 and also pointing away from Dobin's Air Force Base,

37:03 which was more than 20 mi away.

37:06 Now, a quick way of calculating how far

37:08 an airliner will glide without power in a straight

37:11 line is taking your altitude in thousands of feet

37:14 and then tripling that to get the distance.

37:17 So, 7,000 ft would give approximately 21

37:20 miles without counting for flap and gear extension,

37:23 which will then also decrease some of the distance obviously.

37:27 So, in a case like this, I would just

37:29 double the altitude instead to get myself better margins.

37:32 And that would mean that at 7,000 ft,

37:34 they would be able to glide about 14 to 15 miles, but not 20.

37:40 In any case, after reestablishing communication with our traffic control,

37:44 the captain now declared an emergency and asked for vectors towards Dobbins,

37:48 as well as the latest weather there.

37:51 Still hoping that they could make it,

37:54 the controller gave them a direct southeast heading towards the base,

37:57 but with so little altitude left,

38:00 there was now no way that they were going to reach it.

38:03 Passing through 5,800 ft and descending fast,

38:06 the first officer therefore called their traffic

38:08 control and explained, "All right, listen.

38:10 We've lost both engines, and I can't tell you the implications of this.

38:14 We only got two engines,

38:17 and how far is Dobbins now?" The controller answered 19 miles,

38:22 which must have come as a sobering shock for the pilots.

38:26 The controller then asked whether they had been able to restart an engine.

38:30 To which the captain again repeated, "Negative,

38:33 no engines." Turning to the first officer, he then calmly said,

38:38 "Just don't stall this thing." And he then started extending their flaps,

38:42 maybe in order to increase their speed margin to stall.

38:46 Now, the first officer kept the DC9 on speed and under control whilst also

38:51 trying to get Dobbins approach charge in front of him as quickly as possible.

38:54 But both of them soon realized that they couldn't quickly find those charge.

39:00 So, the captain instead asked their traffic control for Dobin's

39:03 weather and approach info and was told to stand by.

39:07 Moments later, now down to just 4,600 ft,

39:11 the captain again asked for the distance only

39:13 to be told that they were still 17 miles out.

39:17 And with that, the math clearly didn't work.

39:20 So he now told the controller,

39:22 "I don't know whether we can make Dobbins or not." The first officer then added,

39:27 "Ask him if there's anything between here and Dobbins." The captain did so

39:32 and at first the Atlanta center controller

39:34 answered that Dobbins was the nearest airport.

39:38 But he then remembered the municipal airport

39:40 in the rural northwest Georgia town of Carterville.

39:44 So he informed the pilots that there were currently 10 mi south

39:47 of Carterville and the captain immediately

39:50 therefore asked for vectors towards it.

39:52 They were told to fly on a heading of 360 due north,

39:56 but even 10 miles at this point was still too far away.

40:01 Tragically, investigators would later discover

40:03 that Cartersville also wasn't the closest airport.

40:07 In fact, when they emerged from that blackout,

40:10 they were well within gliding range of a small

40:13 general aviation field called Cornelius Moore Airport in Georgia.

40:18 Its only runway was about 1,200 m long,

40:22 which would have been just enough for the lightly

40:24 fueled DC9 to get down with maximum braking,

40:27 but that airport was not on any of the charts carried by the flight crew.

40:31 And because it was outside of the area covered by Atlanta Center,

40:35 it wasn't depicted on their radar scopes either.

40:38 So, no one ever realized that it was an option.

40:42 Anyway, as all of this was going on in the front, back in the cabin,

40:45 the forward flight attendant had cracked the cockpit

40:48 door open to ask what was happening,

40:50 to which the pilot snapped at her to just sit down.

40:54 She therefore just backed out again.

40:56 But having seen that the windshield was shattered

40:59 and all of the chaos inside of the cockpit,

41:01 she understood that an emergency landing was imminent.

41:04 So, she now began preparing the passengers by explaining how

41:08 to open the exit doors and how to brace for impact.

41:12 She also called the flight attendant in the back and began discussing

41:15 the best way to prep themselves and their passengers for what was to come,

41:19 even suggesting that they should all take off their shoes so that they

41:22 wouldn't damage the slides if they had to use them during an evacuation.

41:27 Now, that was actually good thinking and standard procedures at the time,

41:31 but in this particular case,

41:32 it would come to have some truly negative consequences.

41:36 The flight attendants also did all of this without being told

41:39 anything by the flight crew solely based on their own assessment,

41:42 which was a great example of professionalism.

41:45 In any case, as the aircraft descended through 4,000 ft,

41:48 the pilots realized that a forced off-field landing was now their only option.

41:53 The captain said that he was picking out a clear field,

41:56 but the first officer demanded,

41:58 "Find me a highway." The captain repeated that they

42:01 should try and take the next clear open field,

42:04 but this section of Georgia was heavily forested back in 1977,

42:08 so large fields were quite rare.

42:11 And the first officer therefore continued to believe

42:14 that their only option was Georgia State Route 92,

42:17 a large two-lane highway running through what was

42:20 then the sleepy rural town of New Hope.

42:24 The captain pointed to that highway and said,

42:27 "There's no cars." But when the first officer asked if it was straight,

42:31 the captain added that it was not.

42:34 To which the first officer only replied, "Well,

42:37 we'll have to take it." The captain now called air traffic control

42:42 one last time to inform them that we're putting it on the highway.

42:46 We're down to nothing.

42:47 And as he did this, he also simultaneously lowered the landing gear.

42:52 Stealing his nerves, the first officer told himself,

42:55 "I hope I can do it." And then, "I got it.

42:57 I got it." And at one point, he even called out a car on the road, saying,

43:01 "I'm going to land right over that guy." With less

43:05 than 100 ft between flight 242 and the highway,

43:07 the first officer continued to encourage himself.

43:10 And finally, when out of altitude and time, he added,

43:13 "We're going to do it right here." While the flight attendants could be heard

43:16 yelling to the passengers in the back to bend down and grab your ankles.

43:21 As the plane descended to just a few feet above the road,

43:24 both wings began to hit trees, followed by utility poles and power lines.

43:29 The last words captured on the cockpit

43:31 voice recorder were recorded that time, 1818,

43:34 just over 20 minutes after they had left Huntsville,

43:37 as the first officer shouted out, "I got it.

43:40 I got it." followed by a curse from the captain

43:42 and the horrific sound of the aircraft breaking apart.

43:46 Both pilots had stomped on their brakes as soon

43:49 as the landing gear was on the road, but it was too late.

43:53 Within seconds, the left wing smashed into an embankment and tore off.

43:57 The plane then jawed violently to the left,

44:00 sending the nose careening into a roadside service station where it sadly

44:04 then struck and killed several motorists who had stopped to get some fuel.

44:09 A fireball quickly engulfed that service station

44:12 and the plane continued sideways through the front

44:14 yards of several houses where huge trees

44:17 soon ripped the fuselage into five pieces.

44:21 The burning wreckage then finally came to a stop after sliding for nearly 600 m,

44:26 leaving a trail of destruction and fire through the center of New Hope.

44:30 And the destruction of the airframe was so

44:32 extensive that many passengers had been killed instantly.

44:36 And even those whose seats had stayed intact had

44:38 only seconds left to escape the smoke and flames.

44:42 Some passengers escaped through openings

44:44 in the broken fuselage sections before heat

44:46 and smoke made movement impossible and others were ejected during the breakup.

44:51 And many of those who escaped did so

44:53 without shoes on which made their injuries graver.

44:58 But the two flight attendants did survive

45:00 and their cabin briefings were later found to have

45:02 been one of the few controllable factors

45:05 that increased the overall survivability of this accident.

45:08 On the ground, local volunteer responders were quickly on the scene.

45:12 But the crash had severed utilities and set multiple fires,

45:15 including that burning service station,

45:18 which turned the rescue into a race against the heat and time.

45:21 Around half of the occupants of Flight 242 perished on impact,

45:25 including both of the pilots.

45:27 And by the time that it was all over,

45:29 another 20 had died as a result of the blazing inferno,

45:32 along with nine people at the service station.

45:35 Two more then passed away in the days and months that followed,

45:38 bringing the total horrifying death toll to 72,

45:42 with 22 passengers and crew members surviving.

45:46 The investigation that followed now had to answer two questions.

45:50 How could a jet airliner lose trust on both engines in flight?

45:54 and why was it in the core of a severe thunderstorm in the first place?

45:59 Now, if you look over here, you will find the answers to both of those questions

46:03 as explained by the NTSB in the final report.

46:07 But I also want to mention that there

46:09 was another hard lesson to be learned here, that highways are not runways.

46:15 While they might be popular places

46:17 for troubled airliners to land in Hollywood movies,

46:19 in real life, they're often some of the worst places to do so.

46:23 and Southern 242 would be the last passenger airliner to ever attempt it,

46:28 at least up until now.

46:30 Today's pilots are unlikely to do something similar,

46:34 thanks to vastly better weather information,

46:37 better knowledge of how engines behave in extreme precipitation and training

46:41 on how to actually deal with a dual engine failure.

46:44 So, as always, this horrible tragedy ended

46:47 up making aviation safer in many different ways.

46:52 Now, I hope that you have checked out our new channel, Mentors Blackbox,

46:56 where my team and I explain accidents and incidents outside

46:59 of aviation in the same way as we do here.

47:02 We will be uploading new videos there by monthly.

47:05 So, please check it out and subscribe.

47:08 And when we're speaking about checking things out,

47:11 just look at some of the love that we've received from our latest episode.

47:16 Please know that we really appreciate each and every one of your comments

47:21 and I read as many of them as I possibly can.

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47:38 It is super appreciated.

47:42 My name is Peter Hornfeld and you're watching Mentor Pilot.

47:44 Have an absolutely fantastic day and I'll see you next time.

47:47 Bye-bye.