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Practice English Speaking&Listening with: Why Aborting From Gemini May Have Likely Killed The Crew

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- Hi it's me Tim Dodd, the Everyday Astronaut.

Climbing on top of a rocket is still actually really nutty

when you stop and think about it.

I mean you're literally riding a controlled explosion,

sitting on top of a column of flames

until the blue sky turns black.

And because of this risky nature,

it's generally considered a good idea

to have a backup in case things go wrong.

Welcome to launch abort systems.

Most human rated vehicles have some type of system

to get crew away from a failing rocket in a hurry,

typically by pulling the crew capsule off of the rocket

with a special set of abort motors.

But did you know that the United States'

second crew capsule, the Gemini spacecraft

had an interesting solution

for getting crew away from impending doom, an ejection seat.

Well today we're gonna take a look

at an engineering solution to a problem

that in hindsight would've almost certainly led to death.

Oh, and there's actually a lot more to it

than just the fact that they used an ejection seat,

that's only part of the equation.

This one's actually a pretty big facepalm,

so welcome to our first episode

of biggest facepalms of space of spaceflight history.

(upbeat music)

- [Technician] Three, two, one.

And liftoff!

- [Neil] That's one small step for man.

- [Technician] Let's clear the traffic for the test one.


- The gemini spacecraft was certainly an important step

in American spaceflight history.

I mean after all it was the first capsule

to fit more than one astronaut,

the first capsule to rendezvous and the first capsule

that U.S. astronauts did a space walk from.

But despite all of its greatness,

there is one thing clearly missing, a launch abort tower.

I mean after all, the Mercury capsule

which flew right before Gemini

had it's own launch abort tower.

So now before we get into why aborting from the Gemini

would've almost certainly killed you,

let's talk about why they thought an ejection seat

was good enough in the first place?

There's three main reasons

and the first one is actually pretty counterintuitive.

The Gemini launched on top of a Titan rocket

which used hypergolic propellants.

And hypergolic propellants

are ones that will ignite spontaneously

upon mixing with each other.

They're also insanely toxic, corrosive and carcinogenic.

I mean there's a reason you got to wear this

in order to handle these.

I mean you can die if you just breathe it in!

But something that's kind of surprising

is due to the fact that they ignite on contact,

if a propellant tank ruptures,

the energy of the blast and fireball

would actually be a lot less energetic

than say cryogenic fuels,

which means less of a need

to remain inside the protective capsule during an abort.

The next reason why they thought it was good enough

is because Gemini's chief designer, Jim Chamberlin,

really didn't like big, bulky and heavy launch abort towers.

After all, he actually wanted the Gemini capsule

to be modular, and even envisioned it landing on the moon.

In order to keep the system

as simple and expandable as possible,

he fought to use ejection seats

instead of the launch abort tower.

Now this is one of those things that sort of confuses me

because the additional weight of a launch abort tower

can be offset because it's typically ditched

only a few minutes into ascent,

unlike ejection seats

whose weight would have to be lugged around

throughout the entire portion of the flight.

But the last reason

why they opted to use ejection seats in the first place

is easily my favorite reason.

They originally planned for the Gemini capsule

to land on a runway using a Rogallo wing,

which was a self-inflating flexible wing.

And now if something were to go wrong

during this final landing phase,

the astronauts could just simply eject

just like a fighter pilot would.

Unfortunately the wing ended up being canceled

and replaced with simple parachutes

after it was unreliable to deploy and even if it did deploy,

it was really hard to control.

If you want to know more about that crazy Rogallo wing

and its use in the Gemini program,

my friend Amy Shira Tietel

has an awesome video all about it.

I mean after all, she wrote her master's thesis on it

and even has a Rogallo wing tattooed on her arm.

Okay, so now that we know

why they went with an ejection seat, let's talk about

why you really, really didn't want to use it.

First off, even when everything goes as planned

with an ejection seat, they're unbelievably violent.

I mean so much so there's actually been cases

of people breaking their backs!

Okay, but broken backs is a better option

than dying in a fiery explosion,

so let's go down the list of other potential problems

with an ejection seat.

One risk was actually witnessed

by John Young and Gus Grissom

who watched a test of the ejection seat system.

The hatch failed to open

and the seat and the dummy punched right through the hatch.

John Young, who in my opinion

was easily one of the funniest astronauts ever,

turned to Gus Grissom and said,

"That's a hell of a headache, but a short one."

Next, say you do make it clear of the hatch

and you've ejected clean

from on top of a 33 meter tall rocket,

well if the rocket happens to erupt

while you're in the air or parachuting down,

it kind of seems like you'd be showered in shrapnel

and if you survive that, you'll be walking through a toxic,

corrosive and cancerous wasteland to get to safety.

Despite my objections

and why this all sounds kind of like a terrible idea,

it actually went through

a solid three year testing period by NASA,

who found it to be quite safe and a good, reliable option

up to about 15 kilometers in altitude,

but after that it's, yeah it's no good.

But lastly, perhaps the most facepalmy

and easily the most dangerous aspect

of aborting from a Gemini capsule

was something that went unnoticed

until after the program ended.

When NASA tested the ejection seats,

they filled the capsules full of nitrogen.

Well, that's great and all, except for the fact

that the Gemini's cabin was a pure oxygen environment.

Hmm, do you see where this is going?

Had the astronauts needed to abort,

they would've been soaking in a pure oxygen environment

for hours, and upon lighting the rocket motors to eject,

they would've likely immediately erupted into flames.

I think Thomas Stafford, said it best,

"I'm glad he didn't.

"Given that we'd been soaking in pure oxygen for two hours

"any spark, especially the ignition

"of an ejection-seat rocket,

"would have set us on fire.

"We'd have been two Roman candles

"shooting off into the sand and the palmetto trees."

But of course hindsight is 20/20

and this was all before the unfortunate lessons learned

during the Apollo 1 fire.

But still, you have to think this was very much overlooked.

But I guess when you're in a space race,

it's probably really easy to overlook things

when you're in such a hurry.

Luckily, no one ever pulled the ejection handle

on any Gemini mission, although the crew of Gemini 6

was literally fractions of a second away

from pulling the handle.

On December 12th, 1965, Wally Schirra and Thomas Stafford

sat in their Gemini spacecraft

waiting for Gemini 7 to fly overhead

for the first orbital rendezvous attempt.

All went really well up to engine ignition.

The engines ran for 1.5 seconds and then abruptly shut down,

which luckily for the crew,

the rocket hadn't quite left the pad yet.

If it had left the pad,

it would've most likely fallen straight back down

and would have probably exploded.

Since the engines were running,

the clock inside the capsule started running too

and the mission rules actually dictated

that the commander, Wally Schirra,

was supposed to pull the D-Ring

that would've ejected both him and Thomas Stafford.

His instincts made him hold back on ejecting

since he didn't feel any acceleration yet.

Since they hadn't left the pad,

they were actually perfectly safe.

Thanks to his quick gut reaction,

he most likely saved Thomas Stafford and his own life.

But then they had to sit there and wait on top of the rocket

for 90 minutes before the area was safe!

Man, I'll bet they were really happy to get down after that!

NASA reset Gemini 6, the rocket was checked out

and then three days later it successfully launched

and later made the first successful rendezvous.

Well, the soviets did actually rendezvous,

but they didn't come this close.

So yeah, come on!

I mean they were beating the United States so bad,

can't they just have it?

Oh and by the way, before we wrap up,

did you know the Gemini spacecraft

isn't the only space launch vehicle to have ejection seats?

That's right!

There's actually two other really famous spaceships

that had ejection seats.

NASA actually put ejection seats on the Space Shuttle.

Space Shuttle Columbia's first four flights

had ejection seats,

which were deactivated by the 5th flight and later removed,

freeing up a bunch of space on the flight deck.

Since there was such a limited use case

considering it was super dangerous

with those crazy SRB exhaust plumes,

the angled main engine exhaust plumes and the fact that

only two of a possible 8 crew members could eject,

it was ditched.

And unfortunately,

they couldn't really add a bunch of ejection seats

for the other crew members

since half the crew was on the mid-deck

which was below the flight deck,

meaning they'd smack into right the flight deck's floor.

Luckily the space shuttle's ejection seats were never used,

but did you know the Vostok capsule,

which was the Soviet Union's first crew capsule,

actually required the use of an ejection seat

in order to have a successful mission?

After reentry, Vostok would land extremely rough

and would've caused serious injuries

to the cosmonaut onboard.

The cosmonaut would actually need to eject

at seven kilometers and parachute down to safety.

The ejection seat also functioned as a launch abort system,

although it wouldn't have worked

within the first 20 seconds of flight

as it didn't allow for enough time

for the parachutes to deploy.

As a shoddy attempt to remedy this,

the Soviets actually put up safety nets

around the launch pad in case the cosmonaut needed to eject.


Ejection seats worked fine on all six Vostok missions

since the Soviets used a mixed atmosphere

of nitrogen and oxygen inside the Vostok,

meaning the cosmonauts didn't turn into Roman candles.

Thank goodness.

So what do you think?

Do you think ejection seats

was actually a valid option for an abort,

or do you think NASA really dodged a bullet

by even allowing them in the first place?

Let me know your thoughts in the comments below.

And definitely stick around,

because we have a lot more really good

facepalms of spaceflight history to get to.

And I owe a huge thanks to my Patreon supporters

for helping me do all of this stuff.

If you want to help contribute,

please head on over to

And while you're online be sure and check out

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lots of other fun stuff,

and including all the music in all my videos.

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Speaking of music,

have you checked out my new three song EP called 27 Merlins?

Where I took the actual sequence of events

of the Falcon Heavy test flight

and I wrote music to it.

That's right, when you watch that video,

the video has not been edited in any way.

The music was actually written to the video.

So it's a fun new way

to experience the Falcon Heavy launch again.

So be sure and check it out and share it with a friend.

Thanks everybody, that's gonna do it for me.

I'm Tim Dodd, the Everyday Astronaut,

bringing space down to earth for everyday people.

(dramatic music)

The Description of Why Aborting From Gemini May Have Likely Killed The Crew