We are in the United States,
in the sunny state of Florida
at Kennedy Space Center.
Hi – I’m Kelsea Brennan-Wessels
and the European Space Agency
together with our partners at NASA
are getting ready to return to the Moon.
ESA is playing a key role in NASA’s Artemis programme,
which will bring astronauts back to the Moon.
The European Service Module
or ESM
will provide propulsion,
power
and thermal control for the Orion spacecraft.
When the first Artemis mission launches on an SLS rocket this year,
ESM-1 will guide an empty spacecraft into orbit around the Moon
in a test of what’s to come.
There are countless steps in this journey to the Moon,
but one of the major moves before launch
is getting the hardware from the Vehicle Assembly Building
to launchpad 39B.
This massive structure is a crawler.
This is going to carry the SLS rocket with Orion and the European Service Module
out onto the launchpad.
We spoke with NASA’s John Giles.
This is crawler number 2 here.
She was built back in 1960s
mid-1960s for the Apollo program
And she's handled Apollo,
and Skylab
and Shuttle,
and now she’s going to be crawler of the future for SLS.
She's been modified over the years for the different programs.
For SLS we had to modify her,
we've had to increase her carrying capacity by 50%.
So we've spent a few years doing that,
and in the last few years we've been getting ready by taking the mobile launcher back and forth to the pad,
and doing a few other tests around here.
She herself
and I know this is rude
but she weighs 6.75 million pounds.
Will carry a mobile launcher that weighs 11.4 million pounds,
and it will carry the SLS launch vehicle which is somewhere around 3.5 million pounds.
Add all that up,
and that's what we'll carry back and forth to the pad,
and then with this mission,
as the launch vehicles get bigger, heavier,
bigger second stages
and bigger cargoes, bigger solids,
the weight just keeps going up.
Our speed to go to take SLS to the pad is going to be 0.83 miles an hour;
that’s the speed they determined will give the rocket the smoothest ride.
The distance from the Vehicle Assembly Building to launchpad 39B
is about 4.2 miles or 6.75 km
so for Artemis
we’re looking at a minimum 5-hour trip to the launchpad.
People don’t realize it, but,
what we’re carrying, does move around a lot.
So those JEL cylinders we have,
have the great task of keeping everything leveled.
We have engineers that are trained to keep it leveled.
And then we have a system that also works to keep it leveled.
So as we roll to the pad in the middle of the night,
We'll get there, takes us about 8 hours,
we'll roll up the pad,
so we'll drop it off
and then we will roll back down to the bottom of the hill.
And that's where we'll sit right outside the gate
and they'll start performing tests
and we'll stay there for as long as they need us to,
and it's usually until a day or two before launch,
until they know everything's in great shape
and they're ready to launch.
Then we'll roll back to what's called the MSS park site,
and we'll stay there.
If they need us for anything,
it’s just a few hour ride to get back to the pad.
As John mentioned,
the crawler has a history in transporting Lunar missions,
but adaptations were needed to prepare for this one.
They were originally designed for 12 million pounds
the requirement for SLS was 18 million pounds
so that’s a 50% increase.
Each corner we call them a ‘truck’,
so the truck consists of two of these tread belts.
57 shoes each.
Each shoe weighs over 2 000 pounds,
and they roll across 11 very large roller bearings underneath
that we replaced when we remodeled this.
So we made them bigger and stronger so they could handle the extra weight.
Right behind here we have a gearbox.
There's 16 of them on the crawler.
They were all rebuilt.
All the bearings were replaced in them.
This, the structure right here is actually hollow inside.
We had to go in there and weld a bunch more steel in there
to strengthen that.
And then that is connected to the chassis
by four very large hydraulic cylinders that we call JELs.
Stands for jacking, equalization and leveling.
Each one of these trucks can turn.
We can rotate them.
They have four steering cylinders that rotates them.
They can turn.
We try to keep it within six degrees.
And we need that turning radius so we can get around turns from here to the VAB
and out to the pad.
We’re looking down at one of the trucks,
you see one of the big steering arms,
You see all the electrical cabling that goes into the motors that turn the gearboxes and propel us.
And then this large thing right here is a steering cylinder.
There's four of those attached to each truck.
Each truck weighs 1 000 000 pounds.
So that's why it takes four of these large cylinders to turn it.
And then right behind us here,
we have two of the jacking equalization and leveling cylinders.
These are very large hydraulic cylinders,
they go down all the way into the base of the truck there,
I believe... we'll say 20 feet deep.
And they can extend up to 26 feet.
There's four of these on each corner,
they’re bigger than the original ones
so they can handle the extra weight.
So inside here,
you have one of the cabs
where the drivers will be.
There'll be at least two in there.
One is actually driving and one is sitting in the front of the co-pilot's chair.
Everybody was on radios during the roll.
Everybody's connected to each other.
Everybody can talk to each other.
The drivers, the engineers, the mechanics, the technicians, they're all in contact.
They're all on the same net
Have a fuel tank here
with 2500 gallons of diesel fuel.
We have two fuel tanks,
one on this in,
one on the other end.
So we carry 5000 gallons of fuel with us at all times.
Our goal is to never stop while we're rolling.
We have...
bathrooms on board,
microwave.
You eat your lunch, your dinner,
your breakfast.
Everything is on board here.
We try not to stop.
If we stop something
probably didn’t go the way we planned
and we gotta fix something.
It’s a wonderful piece of machinery.
If you’re an engineer,
this is the greatest thing ever.
For more about ESA and Europe’s push to the Moon,
you can visit our website
at www.esa.int.
I’m Kelsea Brennan-Wessels
have a great day!