Hello, friends!
On 28th April 1988,
around 1pm,
in Hawaii, the Aloha Airlines flight 243
was about to take off.
It was a beautiful day.
A sunny day.
And most of the passengers were there to enjoy their holidays.
In case you don't know about Hawaii,
it is a group of islands in the Pacific Ocean,
and is a part of America.
They are beautiful islands
and their capital is Honolulu.
This flight was actually travelling from Hilo to Honolulu.
Hilo is the southernmost island of Hawaii.
It wasn't a huge distance.
It was a 35-minute flight.
A routine flight.
The Aloha Airlines is a local Hawaiian airline
which connects the various islands.
Because of the short distances,
this specific plane had already flown 8 times since morning.
It had gone on 3 different round trips.
But this wasn't unusual.
It's normal for such planes.
Everything was going as it should.
Passengers board, the doors were closed,
and at exactly 1:25 PM,
the flight took off.
There was one unusual thing though.
When one of the passengers was boarding the plane,
before entering the door, she saw that
the rivetted sheets that make the body of the plane,
one of those sheets had a little crack,
but she didn't tell anyone about it thinking that
it won't make a difference,
since this was a reputable airline,
and the plane used to fly regularly.
Assuming that it was inspected regularly.
And that someone would have noticed if there were any problems.
She though that it was inconsequential.
But no one could have imagined how devastating this was going to be.
Only after 10-15 minutes of the plane's take-off,
the air hostesses brought in the trolleys
and started serving drinks to the passengers.
The seat belt sign wasn't turned off yet,
because it is usually turned off only when
the plane reaches cruising altitude.
And for this plane, the cruising altitude was 24,000 feet.
There were three air hostesses on the flight,
serving drinks to the passengers.
And just 20 minutes after the take off,
the flight reached its cruising altitude of 24,000 feet.
And as soon as it reached this height,
there was a big blast.
The passengers heard a loud bang
and there was a sudden rapid decompression.
People have trouble breathing.
Things went flying all around.
Total chaos and terrible confusion.
No one could understand what was happening.
Some passengers looked around and saw that
the plane's roof and surrounding walls were missing.
They could see the sky above them.
What happened was that
about 35 m² of the front of the plane's body
had disintegrated and blown away.
What usually happens is that
the air is always pressurised in cabins in a plane.
So that we can breathe normally.
Otherwise, at a height of 24,000 feet,
the atmospheric pressure is very low,
the air is so thin that we cannot breathe normally at that height.
That is why aeroplanes have their own pressurisation system
which regulates the air by pumping it.
If for some reason this system breaks down
and the aeroplane keeps flying at the same altitude
then in case of this emergency,
those oxygen masks will drop down.
You must have heard about this in the safety briefings,
"In the event of loss of cabin pressure,
oxygen masks will drop."
These oxygen masks, typically contain an oxygen supply for about 15-20 minutes,
during which time the pilot has to get the plane to descend
to an altitude where
people can breathe normally.
At a height below 10,000 feet.
Now, in our story,
what happened in Flight 243 is that,
the oxygen masks did drop,
but the oxygen mask system was not working.
Due to the plane's roof being blown away,
the oxygen mask system was completely destroyed.
People were concerned about hypoxia.
The condition in which if your body does not get sufficient oxygen
you can get unconscious and eventually, lose your life.
Within seconds, people started feeling dizzy and confused.
In such cases, it takes only 1-2 minutes to lose consciousness.
Michelle Honda, an air hostess, was near Row 15 during the explosion.
She tried contacting the cockpit through the intercom.
But there was no response from the other side.
The second air hostess, CB Lansing, was serving a drink to a passenger near Row 5.
When the roof of the plane blew apart,
she went flying out of the plane.
Their third colleague, Jane Sato, was near Row 2.
She fell to the floor
after being hit by a flying luggage.
There was commotion all around.
When Michelle didn't get any answer from the pilots,
she went to each and every passenger to ask,
if they knew how to fly a plane.
This scared the passengers further.
They were being asked to fly the plane.
This made them wonder about the pilots.
Without trained pilots, they were doomed to crash.
She reached near the cockpit by crawling on the floor.
There she saw her colleague Jane's head was bleeding.
When she tried to look inside the cockpit,
she couldn't see anything.
The cockpit's view was completely blocked.
There were only a few precious minutes
after which all of them would lose consciousness and d!e.
But apart from hypoxia,
these passengers had to bear strong winds.
Winds as fast as nearly 500 kmph speed were blowing at them.
It was difficult to keep their eyes open.
And the temperature was at -45°C at this height.
Even if there was oxygen supply somehow,
it wasn't possible to survive long in that cold.
Because most of the passengers were wearing shorts and t-shirts.
Hawaii is a tropical place
where people go to see beaches and jungles.
There is no snow here.
So no passenger was prepared for this temperature.
Michelle was the only air hostess in her senses.
She kept trying to contact the pilots.
"Can anyone hear me?"
But there was no answer.
Among all these dangers,
the good news was that
the pilots were actually alive.
And not just alive,
the pilots were in much better condition than the passengers.
Their oxygen masks were thankfully working.
44-year-old Captain Robert Schomstheimer was in command.
A highly experienced pilot working for Aloha Airlines for 11 years.
With him was the 36-year-old First Officer, Mimi Tompkins.
When the explosion happened,
both of them felt the shock.
And when they turned around to see,
they saw that the plane's roof was missing
as well as the cockpit door.
There was debris all around,
but both of them immediately got to work.
First of all, they wore their oxygen masks
and considering the situation,
they decide to go for an emergency descend.
They flew the plane at the speed for 500 km per hour,
and descended at a speed of 4,100 feet per minute.
But the time constraint wasn't only for the descent of the plane.
They had to face another problem, bigger than this.
It was found that due to this incident,
the nose of the plane,
the front part in which they were sitting,
was drooping down a bit, only by about 1 metre.
The floor of the plane was the only thing
holding the cockpit and cabin together.
If they kept flying so for a long time,
the two parts might break apart.
Mimi Tompkins contacted Honolulu
and informed them about their situation.
They were told to land the plane in Maui instead of Honolulu,
since it was closer.
At 1:48 PM, she contacted Maui tower and informed them about the situation.
It was about 3 minutes since the plane's roof had flown away.
But thankfully, the plane was at 14,000 feet.
At this height, it wasn't difficult for most passengers to breathe.
And since it had descended within 3 minutes,
most people didn't lose their consciousness
and at least the risk of hypoxia was over.
Mimi Tompkins contacted Maui Airport and told them
to keep all emergency services ready.
Anything could happen.
Firefighters and rescue vehicles were at standby on the runway.
Everyone was waiting for this plane to land.
A minute later, the plane had reached the height of 10,000 feet.
When another problem arose.
There was a 10,000-foot mountain in front of them.
The Haleakala Summit.
This mountain was between the plane and Maui airport.
Captain Roberts slowed down the plane.
210 knots,
200 knots,
170 knots.
They keep slowing down.
They fly it as slowly as possible.
Any slower and it would be difficult to control the flight.
Maintaining this speed of 170 knots,
they navigate the plane between two islands.
The plane evades the mountain and turned towards the airport.
At this point, the passengers could understand the situation better.
They finally realised that the plane was flown by a pilot;
not only was the pilot alive but he was flying the plane expertly.
As the plane went towards the runway,
Mimi Tompkins deployed the landing gear.
There should be 3 sets of wheels,
2 on the rear and 1 on the front.
The ones at the rear are called the main gear;
the indicator showed that the main gear was successfully released.
But the nose gear,
the wheels at the front,
weren't releasing properly.
Now, technically speaking,
it is possible to land without the front wheels, the nose gear.
This is known as Belly Landing.
And it is done during emergency cases.
But in this specific case,
where the middle portion of the plane was so weak,
and the roof was already missing.
The pilots were afraid to attempt a belly landing
because then the plane would crash definitely.
And if something happened to the fuel tank
there could even be a blast.
"This airplane, and the condition it was in,
because it didn't have a nose gear,
because when the nose touch down on the runway,
it would've broken the airplane apart,
therefore, breaking probably the fuel tanks apart.
Which could lead to a very dramatic fire and explosion."
But there was no other option
there was nothing else they could do.
The pilots decide to attempt landing like that.
As soon as the runway was visible the passengers were holding on for the landing.
Some started praying.
Others were hugging the people around them.
This could very well be the last time they saw each other.
Most of the passengers were still terribly scared.
All for a justified reason.
As the plane descended,
it had started moving side to side.
The pilots realised that
their left engine had failed.
They tried to manually restart the engine,
but unfortunately, they couldn't restart it.
By this time, the emergency services were prepared on the runway.
Firefighters, ambulances, evacuation teams
everyone was preparing for the worst situation.
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Now, let's get back to our story.
At 1:56 PM, the pilots informed the Maui Tower,
that they will need all the equipment the airport had.
Meanwhile, a person on the runway
was tracking the plane with binoculars.
That's when he spotted,
that the nose gear was successfully released.
The plane didn't need belly landing.
They informed the pilots.
One less thing for the pilots to worry about.
Then, at 1:58 PM,
exactly 13 minutes and 42 seconds after the explosion,
Aloha Airlines Flight 243
touched down on the runway.
Apart from using the brakes,
the captains used the thrust reverser of the remaining engine.
Gradually, the plane came to a halt safely.
The emergency teams present on the runway breathed a sign of relief.
The passengers were deboarded from the plane through the emergency exit.
There's a real video of this,
which you can see on the screen,
you can see the passengers safely sliding down.
The passengers applaud the captain
and thanked him for saving their lives.
Although most of them were safe,
many of them were seriously injured.
An 84-year-old female passenger
who was sitting on seat 5A
had a skull fracture and suffered the most injuries.
The passenger sitting in 6A suffered a broken hand.
The passengers in 4A and 4F were seriously injured.
Basically, most of the passengers in Rows 4 to 7
were seriously injured.
Because the roof of this area had blown apart.
And the passengers in Rows 8 to 21
were only minorly injured.
Apart from this, there were 21 passengers
who weren't injured at all.
Air hostess Jane Sato remained unconscious
she suffered only a concussion.
Air hostess Michelle Honda was safe
and after landing she counted the number of passengers to check
whether any of them were missing.
And it turned out that miraculously,
everyone was safe and alive
except for one.
58-year-old air hostess C.B. Lansing
was the only one who passed away in this incident.
Search teams tried to find her later,
but unfortunately, her body couldn't be found.
She disappeared into the depths of the sea forever.
And the remaining 94 people
were grateful to have survived.
Was it mere luck that they survived?
No.
The credit goes to the technical equipment.
I am talking about the seat belts.
The biggest reason why so many people could survive.
As I told you in the beginning,
because this flight hadn't reached cruising altitude,
the seatbelt sign was still on
and people were wearing their seatbelts.
Had the people sitting in Rows 4 to 8 hadn't worn their seatbelts,
they too would have flown out of the plane.
After this incident, as this news spread,
the photos of this plane were published in newspapers globally.
A miracle flight without a roof.
After this, America's National Transportation Safety Board
sent a team of investigators to investigate this incident.
To find the cause of this incident.
The investigation team found that
this plane had completed 89,680 flight cycles and 35,496 flight hours.
The fuselage of this plane,
the main body of the plane,
was weakened due to fatigue and corrosion.
Everytime the plane was in the air,
the metal sheets on it expanded due to the pressurised cabin.
And when it was on the ground,
the fuselage contracted.
This constant cycle of expansion and contraction made it weak.
This was a Boeing 737 plane
whose fuselage is made of aluminium sheet metal panels
arranged circumferentially in a frame.
Each panel overlaps each other by 3 inches.
And the overlapping area is called the Lap Joint.
Because the thickness of these sheets was only 1 mm,
Boeing developed a bonding process
to allow the skin to absorb stress like a single unit.
The company used a strong glue called Epoxy to join the different parts of the plane.
When this glue dried,
a strong bond developed
to distributed the stress in all the plates and to prevent any cracks.
Glue wasn't the only way to keep these sheets together.
In addition to the strong bond of glue,
there were three rows of rivets on every overlap.
The overlapping parts of every sheet
was riveted together so that
the entire frame of the aeroplane could be secured.
Boeing's first batch of 737 aeroplanes
used this method to join the sheets.
But later on, problems arose due to using this method.
They found that when the moisture content in
the air was high, the bonds became weaker.
The epoxy glue started degrading
and the metal started corroding.
This meant that the stress on these sheets
were borne by the rivets instead of the glue.
Because of this problem, in 1972, Boeing decided
to use a new method of attaching these sheets together.
They started using Hot Bonding.
It uses heat and pressure to attach two sheets together.
Friends, interestingly this hot bonding system
was already being used since 1972.
And the Aloha Airlines Flight 243 incident
happened 16 years later.
So, this airline was blamed
for still using the old aeroplane.
Boeing had issued a service bulletin in 1972
stating the issue with their planes and possible problems it may cause.
In fact, in 1987,
one year before this incident,
Boeing issued an Alert Service Bulletin
that their older planes should be inspected and repaired properly
in case any airline was still using them.
Apart from this, Boeing had a Safety Design
stating that in case of a tear in the fuselage,
it needed to be limited to a 10 inch by 10 inch square.
They had placed Tear Straps at every 25 cm of the plane's body.
So that even if any part of the plane's body tore,
the tear wouldn't spread to the rest of the body.
But the Flight 243's condition was so terrible,
that there were numerous cracks across it.
So many cracks that these tear straps weren't really useful.
The NTSB said that when this flight reached its cruising altitude,
the pressure exerted reached its peak
because of which the individual cracks came together
and the entire section of the roof blew apart.
NTSB's final report listed three main reasons for this incident.
First, the management of Aloha Airlines did supervise the maintenance program properly
and did not assess the inspections and quality controls properly.
Secondly, they blamed the US Federal Aviation Administration to some extent
for not requiring a through thorough inspection of
the joints while issuing the Airworthiness Directive.
Whereas Boeing had recommended this.
However, the FAA had definitely told Aloha Airlines
to use a new testing method to find cracks in the plane's body.
The Eddy Currents technique.
In it, electic crurrent is passed through metal
to detect even the smallest of cracks
which aren't even visible to human eyes.
Aloha Airlines claimed that they did use this technique to find cracks
but they were later found to be lying
They didn't inspected their planes properly.
Third, when it was discovered that there
were problems with the old bonding technique
both Boeing and FAA took these issues lightly.
Boeing had designed its 737 plane to fly for 20 years.
With the set time limit at 51,000 flight hours and 75,000 cycles.
Even though the total flight hours of Flight 243 was lower than this,
this plane was used for short distance flights.
Because of this, its flight cycle count was at 90,000.
Whereas Boeing had recommended a service life of only 75,000 cycles.
The plane was near the end of its 20 year life.
Which was another reason for this incident.
A positive outcome of this incident was that
all of Boeing's older aeroplanes
were inspected again.
And do you what did they find?
Many of them had cracks.
Similar to the cracks in Flight 243.
This proved that this problem
wasn't limited to this plane.
Other planes of this fleet had the same problem.
Another positive outcome was that
ever since this incident,
safety regulations are made stricter all over the world
to prevent such accidents from happening ever again.
In 1991, the Federal Aviation Authority launched its Aging Aircraft Safety Program.
As per this Program, all old aircraft
will need to undergo mandatory inspections and control programs.
After this, the techniques used in aircraft maintenance to detect cracks
have also been changed forever.
Using Eddy Current, ultrasonic testing,
methods that don't rely on human eyes,
are now used to detect such cracks early on.
New rules were made for high-cycle planes.
Like the Aloha Airlines flights, there are other short duration trips,
where the planes have to complete as many as 10-20 flights a day.
They are now required to be inspected more frequently.
The American government passed a new law.
The Aviation Safety Research Act, 1988.
To better understand and plan for the structures and issues of ageing aircraft.
Overall, this one incident, friends,
changed the aviation safety standards forever.
Because of this, thankfully, since then,
an incident of this level hasn't occured again.
While there have been so many improvements in the world of science and tech,
there are still some people who fail to apply even the basic concepts.
The strangest example of this is the Titan submersible disaster.
It took place last year.
I explained it in this video.
This submersible was on a tour visiting the wrecks of Titanic.
We saw a billionaire's carelessness
turn into a horrific accident.
You can click here to watch it!
Thank you very much!
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