Kind: captions
Language: en
and the nozzle so as you're saying
there's a bunch of different design
options but it's a critical part of this
how you do that conversion basically
like how much can you convert is really
like the ultimate game how much pressure
and heat can we convert into thrust like
that's really at the end of the day
that's what a rocket engine
is the following is a conversation with
Tim Dodd host of the everyday astronaut
YouTube channel where he educates and
inspires
all of us with detailed but accessible
explanations of Rocket engines and all
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Freedman podcast to support it please
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description and now dear friends here's
Tim DOD can you give a brief history of
SpaceX Rockets so we got Falcon 1 Falcon
9 there's different versions of those
Falcon heavy and Starship and also the
the dragon capsules and so on well uh
yeah Falcon 1 is where it all started
the original intent and the original
idea of of SpaceX was Elon wanted to try
to get something to Mars you know um he
saw that NASA didn't have a current Mars
plan and he wanted to go to Mars so he
decided how do I best do this um he
literally wanted to at first purchase a
rocket from from Russia uh then on the
after a foiled attempt at doing that he
decided to he was going to try to
develop his own rocket and the Falcon
one is what came out of that process and
he developed a pretty incredible team
like I don't know how exactly he
stumbled upon the team that he stumbled
upon that quickly but the people that he
assembled were amazing and they built
the Falcon 1 which was a single Merlin
engine followed by an upper stage engine
called the krol engine um pretty small
compared to the things they're working
on today but that Merlin engine
continued to evolve uh into being the
power plant for the Falcon 9 they went
from a small lift launch vehicle up into
the medium class launch vehicle so they
could provide services for NASA um
that's one of the big things they first
kind of hung their hat up was they got
the opportunity to fly cargo to the
International Space Station under um
originally was called the cots program
the commercial orbital transportation
services uh for NASA which evolved into
the commercial resupply contracts and
that's when SpaceX developed both their
Dragon capsule which is a uh uncrewed at
first uh spacecraft that can dock to the
ISS and the Falcon 9 rocket that can
take it to the International Space
Station and then dragon rides on it's a
thing up top that rides on the big
booster thing that uh that launches it
into orbit exactly yep the Falcon 99's
the the semi- TR the dragon capsules the
payload you know it's the thing being
dropped off basically at its destination
in this case the destination is the
International Space Station um and uh
yeah so they developed those relatively
quickly and uh became a commercial
success before for you know it they're
now the number one launch provider in
the world launching more mass to pay to
orbit than anybody else launching more
frequently than um countries like the
entire country of China who's going
crazy right now with launches granted
China beat them by two launches this
last in 20122 but prior uh prior year
SpaceX beat the entire country of China
I mean it's it's nuts what and just like
you said SpaceX still beats China even
this year in terms of the amount of
payload those so the yeah the mass to
orbit right that uh China had like 60
something a couple more uh launches but
the there was just like small cubes that
type of launches exactly some of them
were literally like 100 kogs or
something you know like not not large
payloads and so SpaceX customers are
different different so whoever wants to
send payloads up into space yes but
right now their biggest customer is
actually themselves with starlink with
one of the biggest reasons they've
launched so much mass to orbit is
because starlink is designed around the
payload Fairing and the payload
capabilities of the falcon9 rocket so
you know because they're vertically
integrated because they build their own
satellites because they're building
their own rocket they can literally
design a system that's you know another
manufacturer might have made a more
Square satellite that was heavier or
something but SpaceX looked at it from a
blank slate and said here's our
constraints our payload Mass constraints
or volume constraints and they made a
funky looking satellite things like the
size of a you know it's like a table
folded up which isn't anything I've you
know really ever seen before so but it's
purpose built to fit as efficiently as
possible inside their Fairing and inside
the capabilities of that rocket so
therefore because they're launching
those like an insane amount you know a
dozen you know 40 50 times a year or
whatever um they're uh they're just
putting up insane amounts of mass like
we've never seen before what about the
different versions of Falcon 9 so we can
Linger on them what are some interesting
memories to you of the different
developments in Falcon 9 the very first
Falcon 9s had a a square array of
engines it had like a 3x3x3 grid of
their Merlin one engines the 1DS and um
I think it only lasted I don't remember
if it was two or four flights before
they went into this OCTA configuration
where um there's eight like a ring of
eight engines with a center engine in
the middle um still in the same diameter
that the rocket was the fuselage was
more or less the same 3.7 M wide
diameter but the the actual thrust
structure changed and one of the big
efficiency gains was you no longer have
you know a corner engine and then like a
edge engine and then another Corner
engine you can just make eight of the
same you know kind of part of the OCTA
web it's called uh you know the same
shape and then the your
interchangeability and your
manufacturability becomes a lot simpler
so that was kind of one of the bigger
upgrades at first and they kept
stretching it every time they like touch
this thing it got longer and like or
taller and taller technically um and
then the next big feature that you saw
uh in 2014 would have been they add
added Landing legs to a Falcon 9 rocket
which was I was at that was the first
launch I ever went to was actually to
see um it was CRS 3 so commercial
resupply Mission 3 it was probably their
God I don't remember what that was like
their 14th or 15th launch or something
like pretty early on um and people were
literally laughing at the idea of them
putting Landing legs on it they just
thought it was stupid they're like why
are they wasting why is this billionaire
Elon mus guy wasting his time trying to
land a rocket it's not going to work so
you said the Mars planet was there in
the beginning
uh what about the re reusability of
rockets was that there in the beginning
uh I think reusability definitely you
know it's it's a necessary part of
making any kind of
interplanetary mission you know in order
to actually do that just financially you
have to start reusing these things in
terms of the development of the Falcon 1
and Falcon
9 how early on did the uh goal of
reusing the rocket having the rocket
actually land
how how early did that goal creep in I I
can't speak for Elon and and SpaceX but
it was pretty you know immediate they
wanted to try to recover and as a matter
of fact I think the very first two
Falcon 9 rockets and Falcon 1 I think
they even wanted to try to recover uh
using parachutes to recover the first
stage um and now fast forward you know
almost 20 years later and Rocket lab is
actually doing a concept like that where
they're uh pulling a parachute after the
first stage is re-entering and they
actually are trying to recover cover it
with a helicopter he's going to try to
snatch it out of the air they've
actually done it they've actually done
it successfully once how does the
helicopter grab the the rocket with this
giant like drag line in a hook oh W and
literally just like grabs snags onto the
parachute wow and it's pretty amazing
and but this is a small rocket their
Rocket's only about a metric ton the the
booster is empty so the rocket releases
parachutes yep like really high up I'd
love to see this yeah it's an
interesting idea there's so many
interesting ideas and possibilities like
SpaceX basically just
innovated a lot of different weird ideas
just in in the pursuit of making things
more efficient reusable um all that so
basically thinking from first principles
how to solve this problem and so what
you find is like you'll get all these
kind of crazy kind of solutions and with
SpaceX they weren't even getting to the
point of the booster surviving re-entry
long enough to be able to pull the
parachutes yeah you know their Mass
fractions you know and that varies every
single Rocket's different you know all
the you know for instance rocket lab
uses carbon composite fuselage and tanks
um or you know same thing and that's
very very lightweight has really good
Mass fractions and therefore their drag
coefficients and things like that they
were able to survive re-entry of the
first age which is something that SpaceX
wasn't able to do at the time um what's
what the kind of the big I think
breakthrough for SpaceX with reusing the
booster is they uh they realized we have
to basically slow down before we hit the
atmosphere so they actually do what they
used to call a re-entry burn which I
still think is the correct term because
it is re-entering the atmosphere but now
they call it the entry burn and they
light up three of the nine Merlin
engines uh not only to slow it down but
actually even while those engines are
firing it creates like a a literal like
force field as it's falling through the
through the atmosphere interesting and
uh but it also decreases the velocity by
almost half or around half and then that
therefore decreases the amount of you
know the biggest thing with the
atmosphere is that it as it gets
compressed against um the the front of
any anything flying through the
atmosphere uh the compressed atoms just
get hot and they can get so hot they
turn into a plasma and they get so hot
they can just absolutely destroy
anything um so they slow down enough
that the air molecules don't end up you
know destroying the vehicle on re-entry
and then they then they realize I think
at some point it's probably a similar
crossover they're like well if we're
lighting the engines already to slow
down in the atmosphere we can just use
that same engine to land MH and so like
well what if we just stuck Landing legs
on it and
just landed the thing vertically and
next thing you know is December 21st
2015 they did exactly that for the first
time they landed so you were there
before that then right yeah in 2014 yep
early 2014 so that and for me like that
was so fun watching you know that was
like the peak of me just becoming
obsessed with uh with this idea I'm
watching with like and back in the day
it was like months between launches you
know so a launch was like a big idea I'd
wake up at 3:00 a.m. to watch this
Landing attempt or whatever you know and
every you know there's crs4 um almost
almost landed crs5 almost landed CRS 6
CRS 7 blew up I was watching that on I
think it was like a Saturday morning or
maybe a Sunday morning and I remember
watching that and watched it blow up and
I'm like oh my God now what you know and
it blew up on a scent it was their first
failure um so it was their 18th flight I
believe CRS 7 the upper stage um had a
uh one of the bot there's bottles inside
the tanks that are filled with helium
and one of those bottles broke off on a
scent mhm and actually just completely
overpressured this the upper stage the
upper stage blew up and the whole rocket
went Kaboom uh in an uncontrolled
Manner and so uh so then they came back
with vengeance when they came back the
first mission back is the first time
that they landed a rocket which was
awesome so they return to flight after
the anomaly was was uh yeah was was
Landing a rocket stuck The Landing yep
well actually the first time so the
first time you were there what was that
like what do you remember from that from
that day just I was surprised at how
much bigger the rocket was than I
imagined I was I originally when I was
going down to Kennedy Space Center I was
disappointed that I wasn't seeing like a
you know I didn't know a ton about
Rockets I knew enough to like know what
a space shuttle was what like the Saturn
5 was you know but that was probably
about the end of my knowledge I just
remember being disappointed that I
wasn't seeing a big quote unquote NASA
rocket flying you know I was thinking in
my head like oh I'm going to see this
launch it's probably going to be like
you know three stories tall or something
you know just some little skinny little
stick and some little firecracker and
yay you know and I think I'd almost been
pitched that too I think the the people
that I was working for at the time I
think they kind of were downplaying it
as like well it's not a big rocket here
it's not going to be that exciting you
know but we get out there to the pad and
I'm like this thing's huge this is not a
small rocket like this is It's you know
it's 70 M tall 220 feet tall it's huge
um and I think people forget like the
scale of that you know it might look
skinny and tall and and all this stuff
but is still a very very large piece of
machinery it's physically about as as
large as you can ship the booster is
about as big as you can ship across the
country period without like completely
shutting down highways you know it is
made within those exact specifications
of of like having you know Lane
Privileges and bridges and everything
it's you know 12 feet wide 3.7 meters
wide and it's 45 MERS long so it's like
exactly what you can fit uh with a
pretty standard you know like before you
start getting into crazy amounts of of
problems shipping the rocket and it's
huge it's huge and people just don't
understand that and so when I saw with
my own eyes I remember just being like
this is so much cooler than I thought is
it hard to believe that that thing is
going to have to lift off the ground and
launch up into the air maybe that's the
most humbling aspect of it that
something that size humans have come up
with a way to take something that size
and launching launch it up into the air
yeah there's certainly a very humbling
aspect when you watch it actually leave
was was there a sound to it was there
like a feeling what what were the
different experiences that you first
remember well ironically I didn't end up
getting to see that one fly oh I went
home my camera saw it I left my camera
out there like a remote triggered camera
uh my first images as a launch
photographer at the time was was CRS 3
but I went home it it scrubbed too many
times this is back in the day they were
scrubbing like often and it'd be like a
threed day five day 7even day you just
never knew so I go home and I watched
the live stream of it so I didn't even
get an experience my first launch and
any anyone that's ever tried to you know
go to a launch is can probably empathize
because yeah scrubs are very common in
the space flight world so that one I
didn't get a see uh but since then
obviously I've been able to um attend
very many launches uh how much do you
understand the control involved in the
landing how difficult is that problem I
couldn't tell you a single thing about
like the code and like the avionics
behind it but I can tell you all the
hardware that makes it happen if that
helps well that I mean to me it seems
like whenever I talk to people they they
say it's not that big of a deal in terms
of the the level of intelligence and the
control but to me it's just like when
you observe it it seems is incredible
cuz all the variables involved all the
uncertainties involved all
the um because there's aerodynamics I
mean like there's different temperatures
there's so so much going on with the
fuel the burning the the combustion just
everything that's going on to be able to
do perform control at such high stakes
effectively like you know I that code is
probably not written in JavaScript I
guess is what I'm saying actually no I
don't it it if I remember I again this
is well outside of my domain um but um
I'm they they code in a Common Language
it's is it's probably it's probably
going to be c yeah yeah I'm pretty sure
it is and that was one of the things
that was weird is that Elon when he you
know started SpaceX was like we're just
going to code in the most common
language so that we don't have to like
have people learn this archaic you know
weird thing and we can just literally
pull people off the streets and be like
here write it you know and yeah it's
probably C++ I mean it'd be epic if it
was like python or something but I don't
I I think like reliable systems have to
be written in cc++ probably which is a
common language which is something uh I
imagine like NASA Engineers would
probably have to use some kind of
proprietary language in uh in the olden
days for for security for privacy all
that kind of stuff um well in the olden
old old days like they're inventing code
and language from scratch uh for sure
but still it's just still incredible
that it's able to do that like just the
feat of engineering involved is just is
truly it's like one of the Marvels to
observe about these Rockets coming back
to Earth uh that they're able to land
like the drama of it is just incredible
to see yeah well the the one of the fun
things to remember too with specifically
with the Falcon 9 and the falcon or
Falcon heavy boosters I mean it's the
same thing basically um they shut down
all but one of the nine engines and even
with that one engine at its minimum
throttle setting it's still too much
thrust to hover so as this Rocket's
coming down if they start a little bit
too early if they light that engine too
early it will actually stop above the
ground and will not be able to lower
itself it will literally stop like say I
stay say it stop 200 feet above the
ground their only option is to kill the
engine and then it's just going to fall
those 200 feet so they it's what we call
like a suicide burn or a hover slam kind
of interchangeable terms because your
thrust to weight ratio is never below
one so they have to actually literally
be riding the throttle so what you do is
you kind of start ideally you know you
kind of start like in the middle of your
window of of throttle range so let's
pretend your engine can Throttle Down to
40% of its maximum rated thrust you
might start at like 70% of thrust in the
middle of that like window of where it
could burn so that so if all of a sudden
it's kind of coming in too hot you have
room to throttle up if you're coming in
you actually you know a little too early
you throttle it down you have a little
bit of wiggle room it's just amazing how
smoothly and how perfectly they're able
to still control that thing even though
they're down to one engine out of the
nine and they're still riding like the
finest margin of what's possible and
they're they're continually playing with
that to try to get it because every
every bit of fuel they're using and
proponent they're using to land is
proponent they weren't using to put
something into space yeah so they want
that to be as efficient as possible so
they're really like watching them hone
that in and and just continue to evolve
and edit that and and just get it to be
the Workhorse we're coming up on a 100
consecutive Landings perfect Landings
100 I think they've done like 150
something Landings all together 160
altogether but we're talking like in a
row without blowing up which at the you
know 5 years ago was completely
experimental and insane and now we're
coming up to the point where we're 100
in a row it's like this is becoming more
reliable in the landing which is not the
primary Mission this is purely for
spacex's like gain is to recover the
booster it has nothing to do with the
effect of getting the payon on orbit you
know most of the time and uh the landing
is really only for their their benefit
and their gain long-term gain like it's
a long-term investment in in uh being
able to recover the the the boosters
can you believe all this was done in
basically 10 years so we've seen this
development over a period of 10 years oh
man so like where we started uh
commercial space
flight at scale to today where it's
almost uh almost starting to be mundane
yeah what FC is able to do yeah uh I I
can't really believe it I mean obviously
even just in the I I think I'm a fairly
fair weather fan really didn't start
paying attention till like 2014 yeah and
just seeing what it was like back then
to what it's like like I don't watch
every launch at all anymore like I'll
catch the big ones yeah I'll stream some
of the really big ones but like back in
the day I like I said would wake up in
the middle of the night to catch these
streams or you know catch these launches
and watch them because they were such a
big deal and there's maybe only five of
them a year you know and so it's a
really big deal nowadays it's like oh
yeah there's literally like two a week
on average now it's insane from SpaceX
alone let alone you know United launch
Alliance rocket lab any of the Chinese
missions you know I mean all of there's
countless it's it's insane it's hard to
really really really hard to keep up
with I wonder at which point in the
future the number of uh launches to
orbit will exceed the number of launches
of
airplanes like on the surface of Earth
see I have to admit I kind of have a
hard time extrapolating out that far you
know there's a lot of people that are
like big futurists and really do think
about like interplanetary stuff and
think about colonizing Mars and stuff I
have a hard time predicting like when
starship's going to fly the orbital
launch you know and that's like imminent
is like month or two scale time frame
and yet I'm still like I can't tell you
when that's gonna I can't tell you
anything about like when we're going to
land on Mars or what that's what that
economy and what that you know the scale
of launch operations is going to look
like in order to do that because it's
just so hard to I wouldn't have
predicted where we're at today five
years ago you know it's it's insane it's
so hard to predict and yeah but it's
it's funny because there's so many like
new companies starting up trying to
predict that and it's a really exciting
you know startup culture right now I
think uh when you make certain
engineering decisions and hiring
decisions and like what you focus on in
terms of both business and Engineering
it's good to think on the scale of 10 20
50 100 years that's one of the things
that Elon is exceptionally good at which
is asking uh the question okay this
might seem impossible right now but
what's the obvious way to do this if we
look out 20 years and then you start to
make decisions you start to make
decisions about robotics about brain
computer interfaces about uh space
travel that are that make a lot of sense
when you look at the scale of 10 20 50
100 years and don't make any sense if
you if you look at the scale of of just
months so but of course the actual work
of day-to-day is focused on the next few
months because there's deadlines there's
missions they have to accomplish anyway
we uh we're turning back to the brief
history of SpaceX
Rockets the Falcon heavy so what what
else is there so we talked about Falcon
9 and the rapid development there what
other flavors of of Falcon is there and
how does that take us to Starship yeah
realistically the Falcon N9 evolved more
or less kind of like just got more
powerful and a little bit longer and
more capable but nowadays they fly
What's called the block five even though
it's like the eighth or ninth iteration
of the the Falcon but they call it block
five it's the one that has the black
Landing legs the black in stage they
have a fleet of roughly 10 or so that
are doing the majority of the leg work
these days and they're flying you know
up to 15 times I think right now is the
current booster leader they're also
recovering the fairings so the nose cone
of the Rockets are frequently if not
every time being recovered um same with
yeah same with the booster for the most
part and the only thing being expended
is the upper stage and that's kind of
where the Falcon 9 is ending it's really
doesn't make sense to develop that
infrastructure any longer so they went
with the next step which is go even
bigger physically so they have more
margin for upper stage reusability and
that's what we see with Starship and
super heavy so the super heavy booster
uh the whole system is confusing the
whole system's kind of considered
Starship but it technically the Starship
is just the upper stage which is also
like the spaceship which is also the
upper stage and then the booster itself
is considered the super heavy booster
and that's what they've been working on
uh publicly it came out in 2016 as the
uh at the time it was the its the
interplanetary transportation system uh
later in I think about 20 by the end of
that year 2017 it kind of became known
as the bfr the big uh Falcon rocket yes
yeah um and then I think it was about
end of 2018 they started calling it
Starship but that is the that is where
we're at today and that's what they're
uh working full steam ahead on and uh
what about Dragon we mention Dragon uh
crew Dragon cargo Dragon yeah so they
went from the cargo version of dragon
that flew uh about 20 times uh
successfully to the AAL space station
except for that one CRS 7 where the
rocket blew up in the capsule obviously
didn't make it to the ISS um then they
went into the dragon TR Dragon 2 which
has two variants it has a crew variant
so we just call it crew crew dragon and
then there's the cargo version of of
Dragon 2 um and that's just an updated
sleeker sexier version of dragon and
it's ironically it's heavier altogether
so it uh you'll never see those those
cool return to launch site Landing the
boosters coming back to land for CRS
missions anymore like like we used to
but they landed on the Drone ship anyway
and um and yeah that's been flying
successfully that's kind of the so
there's yeah starlink Dragon falcon9
Falcon heavy and Starship system is kind
of the whole the whole SpaceX world
really in ter in terms of the the the
spaceships involved what do you are some
of the major milestones in that history
we kind of mentioned a a few stick in
the landing is is there something that
kind of stands out yeah I would say
definitely um the big ones obviously
like any of the first the first flight
of Falcon 1 First Flight of Falcon 9
first time they went to the
International Space Station um the first
time they landed a booster um the first
time they reuse a booster which is I
think about six months after no oh it
was a year after it was
scs1 um
2017 was the first time they they reused
one of those boosters you know and that
was a big milestone like can we even
yeah we recovered one we we caught one
you know it's like we got one now what
um that was the first time they refle
one um yeah then flying humans was a
huge one dm to Bob and Doug um for NASA
Bob and Doug yeah Bob and Doug that was
incredible you know that was that was a
huge huge step I think for SpaceX was
flying people so it's it's first major
commercial launching of humans out into
space yeah and not just into space
because you know there's been people
that have done you know space flights
with you know like suborbital hops but
going into orbit and especially docking
and roning with the International Space
Station is a it's a big deal it's a
whole it until you really understand the
physics involved and the scale involved
of like just crossing the Cara line
going straight up versus going into
orbit like they're just completely
different things almost what about uh
Starship are we are we in a place where
we can talk about Milestones with
Starship has there been or has it just
been an Epic Journey of failure and
successes of testing and and so on was
there like yeah what would you classify
at this point as a as a milestone a
Starship or be a whatever the name is
was able to achieve well so far the
Milestones we've seen I'd say the first
one would be the Hop of they call it
starhopper and it's basically a very
rudimentary rocket but it was the first
time they they utilized their new Raptor
engine to produce thrust to to fly
something it first flew like literally
like 3 MERS off the ground or something
like Tethered to the ground then it flew
like 15 and then finally it flew 150 m m
um and that was in
2019 and that was the first big
milestone of of Starship then after that
we saw uh sn5 sn6 kind of do the similar
like 150 M hops with a little bit more
elegant systems you know proving out
more of their their tank building
proving out more their you know a lot of
just subsystems and then the big ones
physically were in uh and end of 2020
and early 2021 when they flew the uh SN
8 9 10 11 and 15 what does the n stand
for an SN I think just serial number or
number these are just names numbers
numerical representations of the
different testing efforts they ski some
numbers right if they if they scratch a
test yeah and lots of times it'd be like
literally they're building you know CU
at Star base and what SpaceX is working
on like the one foot is always in front
of someone else's foot and like the arm
is not knowing what the leg is doing
sometimes yeah they they will have
someone working on you know they'll just
be like hurry up and build 40 of these
tank sections and you build the bulkhead
and you build the downcomer and you
build the header tank blah blah blah and
all of a sudden like oh we actually
evolved that we don't use that header
tank now so it's going to go on to this
one so they'll have like parts of
certain Rockets built like ah literally
scrap it like not scrap it like in the
you know joke term but like literally
just go scrap it and they uh so yeah
they just evolve and iterate so quickly
there were some epic
explosions um I think Starship something
about it uh probably just the amount of
fuel just leads to some epic epic
failures oh yeah probably would you say
Starship is the source of the most epic
failures in terms of size of explosion
so you can literally measure in like a
yield of explosive power you know like
like you could TNT like you can take a
look at uh how much propellent is left
over at the at the time of the exposion
and you know Starship what what's flown
so far even though it's physically one
of the largest flying objects ever uh
just with the upper stage alone they've
not filled it more than like 10 or 20%
full of propellant yeah and so it
actually hasn't been the the failures
have been really epic looking uh big
visual ual Fireballs but in terms of
space fight they're still pretty small
explosions believe it or not they could
still go bigger oh yeah a lot a lot and
of course the test payload of a Tesla
rooster was launched um I forget what
year that was yeah that 2018 that that
was quite epic would you put that on a
milestone oh yeah yeah Falcon heavy demo
was like definitely a a big big big
milestone yeah is that funny to you that
there's a Roop floating out there do we
know the location of that Roadster at
this point oh yeah where is roadster.com
yeah oh yeah where's is it orbiting
something yeah it's orbiting the Sun so
it's it's orbiting the Sun and its orbit
is basically between the Earth's orbit
and Beyond Mars so I think up like 2.5
Au if I remember right so it's it's
beyond Mars's orbit at its highest point
and it's back at Earth kind of in its
lowest point I wonder if there's a
mission where you're going to somehow
connect with it once again and like
Place extra things into it I wonder how
challenging that is technically oh yeah
it could it could absolutely be done um
you know the the hard thing at this
point because it's on an eccentric orbit
would be Rend deing with it because you
kind of have to be in alignment with its
orbit to really line up well with it
yeah um but yeah I mean someday I don't
see any reason why we couldn't at least
and for sure an uncrewed you know Elon
wanted to just fly a a robot out there
to check up on it and photograph it or
something like we could that could be
well within the realm of things and get
an Optimus uh robot up
there uh so that was a story uh
brilliantly told by you of the Rockets
uh for SpaceX what about through the
lens of engines uh can you give a brief
history of the SpaceX rocket engines
that were uh used that we haven't
covered you mentioned it all started
with the Merlin engine and a cust engine
what um yeah through that that lens yeah
what's there the engines are relatively
small number which is which is easy for
us there's yeah the Merlin Merlin's
evolved throughout time to be from like
the Merlin to the Merlin 1C to the
Merlin 1D to the Merlin full thrust and
all these other kind of tweaks of the
same architecture uh krol ended with
Falcon 1 um they also have the Morlin
vacuum engine which is the upper stage
engine for Falcon 9 same relative uh
system but just optimized for vacuum so
it has a much larger Bell nozzle there's
the Draco thrusters which you know you
kind of consider engines well they are
rocket engines but they're just small
they're not like the orbital engines
there's the super Draco engines which
are the abort thrusters on on crew
Dragon capsule and then nowadays they
have the Raptor engine and the Raptor
vacuum variant um but they've already
had two versions of raptor we've already
seen kind of the Raptor development
engine um we've kind of seen like a
raptor 1.5 where is kind of taking hints
of the future Raptor but now we're well
within the well within what you know
you'd consider a Raptor 2 variant and
that's really it yeah for the uh the
Raptor maybe I'll ask you that
separately but I like in general and
people who doesn't know whoever
astronaut is but if you don't somehow
know go go go check his your YouTube
channel out you're an incredible
educator about the the super technical
and uh the more sort of even the the
philosophical the actual like the the
actual space travel so you go down to
the raw details of it and there's just
great videos on the Raptor engine um I
think you have one on Merlin uh and and
also actual tours with Elon where he
discusses some of those things on one of
the tours he said says uh he's full of
good lines that guy uh he says something
about uh the number of fiddly bits and
he's uh the number of fiddly bits was
decreased between Raptor 2 and Raptor 1
yeah and I I think that's actually a
really beautiful representation of um
the engineering efforts there which is
constantly trying to simplify oh yeah uh
increase the efficiency of the engines
but
also uh simplify the design so you can
manufacture it and in general
simplification leads to better
performance and testing you know and
everything so the number of fiddly bits
I'm sure there's a Wikipedia page on
that now as an index is actually a
really good one well and when you think
about it I I don't know of any other
company prior that had kind of tried to
measure their performance of their
engine not in like thrust to weight
ratio or like how efficient it is like
in specific impulse but literally in
like dollar to thrust ratio like how
much does this engine cost how much
thrust can it produce and like using
that is a trade study instead of just
like pure metrics of you know because at
the end of the day like okay if it's if
it's cheaper and does you know x amount
of work even if it's less efficient it
can actually be better long term and so
I guess another way it's not even just
thrust I don't know if that metric is
used but basically the cost of getting
one
kilogram of thing up into space yeah
that's basically what they're trying to
minimize especially yeah at the end of
the day that is definitely the ultimate
metric is how much does one kilogram
cost to orbit eventually you know and
but there's it's so funny cuz space FL
is just the ultimate you know it's the
ultimate compromise every little thing
any variable can just change everything
else so you can tweak so many different
things to get to different numbers and
conclusions you know but even things
like on your first stage when you're
when you're the Rocket's pointing
straight up and the engines are pointing
straight down you're dealing more with
the thrust to weight ratio of the rocket
so how much thrust is it producing
versus how much is gravity pulling down
on it is actually a more important than
how raw efficient the engine is so it's
funny then in space it's kind of the
opposite thrust to weight ratio doesn't
really matter uh what really matters is
the actual the specific impulse it's
called or like the the nozzle escape
velocity of the or the injection
velocity of the how fast is the the gas
moving is like the more important number
on orbit but it's it's just so crazy
because there's all these like I would
just love to see the trade studies you
know when you're like trying to figure
out like is this more important than
this or this or this and it's like you
change this one little thing and all a
sudden
you know like all the everything changes
it's just even the profile like the the
launch profile the trajectory of it the
I mean
everything everything I I wonder what
that trade-off discussions are like cuz
you can't really perfectly plan
everything so and you always have to
have some spare
leway you know especially as you're
testing new vehicles like Starship yeah
margins are important yeah having having
a margin given all the uncertainty
that's there that's really interesting
like how they do those kinds of
tradeoffs cuz they're all rapidly
designing and redesigning and
re-engineering and uh the ultimately you
want to give yourself the freedom to
constantly innovate but then through the
process of testing you solidify the
thing that can be relied upon especially
if it's a crude Mission yeah that that
how to do that in a rapid cycle I I
remember at some point that NASA as
they're leading up to Flying humans for
the first time for NASA um you know
there's some talk that like we're going
to do a design freeze because SpaceX
does evolve and iterate so quickly you
know they were saying that it was
leading because especially at the time
it was a mission called Amos 6 and they
lost a rocket they've only lost two
rockets like ever really as far as um
you know trying to get something to
space for the Falcon 9 sorry um and the
second one Amos 6 I mean that was back
in 2016 so it's it's been a long time
and uh but at the time you know they're
looking at flying humans in in the near
future and it's like if you guys keep
tweaking this thing every time you take
it out to the pad there's going to be a
problem you know and so there is some
pressure from NASA to kind of slow down
on that iterative process and uh but
that is also why they were able to
evolve the Falcon 9 to be what it is
today is because they did just evolve it
so quickly literally like one after
another was never really the same and
we're definitely seeing that with
Starship now like it's evolved so
quickly that you just can't even keep up
with it you know so there's a
fascinating culture uh Clash there have
you just in observing and interacting
with NASA folks seen them sort of grow
and change and evolve themselves sort of
inspired by this new developments in
commercial space flight oh yeah yeah
there's a lot of especially like around
dm2 there's a lot of talks and the press
conferences and stuff where you'd hear
people say you know this was a big this
is well outside of our comfort zone to
work with SpaceX in this manner because
we're we take this approach to things
we're X Y and Z in this in this way the
way normally certify things and we're
not used to SpaceX like well let's just
try it you know like and and do
something you know to a point and so
they they said it ended up being
fantastic they loved working that way
because it was just less paperwork
almost and more just do and um and but
at the same time SpaceX I think even
expressed I I don't remember if it was
Hans cigman or someone in a press
conference said well we really liked
having someone just double check us so
that we're not doing something super
stupid right before we test something
you know um so there was a cool
collaboration because it is uh two very
different philosophies of uh of
development and managing you know space
programs I wanted to talk to you a lot
about engines uh and maybe about
Starship and maybe about your own
becoming an actual astronaut but like
let let's just go there uh before all
that and and and talk about the actual
culture of SpaceX and uh your
conversations with uh Elon you've tour
SpaceX facilities with him you've
interviewed him you've interacted with
them uh what have you learned about
Rockets about propulsion about
engineering about design about life from
those interactions um he's pretty
transparent open human being as an
engineer as a as a leader as a
person I would definitely say the
biggest takeaway I've had from my times
with Elon at SpaceX is really like the
the idea of questioning your constraints
he says that a lot but he also does it a
lot like he there'll you know there'll
be times where like you'll see him
change on a dime because he's like
rethinking of something in a in a new or
different way and for me you know I I I
think we all put constraints on
ourselves we we think about our own
limits you know on on things that we can
or cannot do and I think it's made me
kind of question like well why am I why
did I say no I can't do that or you know
you know just off the top of my head it
a good example uh I so in Iowa I live in
Iowa or half the time or whatever uh
there's a a bike ride across the state
of Iowa called ragb and every year you
just you know like thousands of people
get together and they they ride across
Iowa and it was last summer uh I met up
with some friends and like hey you want
to go on ragb this year I'm like it's
like a week away they're like yeah you
want to go I'm like yeah and so I did
without and it was one of those moments
where I was proud of myself because like
I it's easy to just be like no you know
I'm not ready or this is my constraint
is like I'm not in shape MH but like
just question that you know and and so I
think when it comes down to questioning
your own constraints it's yes even to
that level of like why do you question
yourself on what you can and cannot do
so that's for your personal life is
really powerful but a little bit more
intuitive I think what's really hard is
the question of constraints in a place
like Aeronautics or or robotics or
autonomous vehicles or Vehicles because
there's people there's experts
everywhere that have done it for decades
and everyone admires those experts and
respects those experts and for you to
step into a room knowing not much more
than just uh what's in a Wikipedia
article yeah and to just use your
intuition and first principal thinking
to disagree with the experts that takes
uh that takes some uh guts I think well
you can't have everyone doing that
either you know like there has to be
some humility of knowing that something
is a hardened concept and a hardened you
know like especially I I'm not an
engineer I don't I don't do this stuff
you know but I can imagine you sitting
there having spent six years on a type
of valve that perfectly managed as crowd
Jun propellants or whatever and someone
walks in and says why don't you just put
a heater element in there you know or
something that's you know something
you're like be because we you know we've
done that 40 times or whatever whatever
you know like I'm sure there are things
like that that are very frustrating but
but see the I don't know what that's
like you know the thing is with the
experts they're always going to be
frustrated when the Newbie comes in with
their first principles thinking but
sometimes that frustration is Justified
and sometimes it's not sometimes it's
just stubbornness for failing to
acknowledge a better way and I've seen
it both directions which is really
interesting so you need you need both
but that tension is always going to be
there and there has to be almost like a
dictatorial uh imperative that breaks
through the the expertise of the way
things have been done in the past to
push forward like a new way of doing it
and elon's done that um I've seen a lot
of great Engineers uh do that in the
Machining machine learning world because
it's been so much Development I've seen
that happen usually when there's like
rapid development that starts to come
into play yeah um and yeah and I've seen
that autonomous vehicle space um brain
computer interfaces that Elana's evolved
with all of it it's kind of fascinating
to watch um what about the actual design
and Engineering of the engine since
you've learned about so many different
kinds of engines over the past few years
just like what stands out to you about
the way that engineering is done at
SpaceX or that Elon does
engineering the hardest thing
to kind of remember is like how much
stuff was developed in the 50s and 60s
you know the the concepts finally being
utilized today were already literally
done in the 60s yeah you know so a lot
of the things that SpaceX is doing isn't
a novel concept per se you know they're
like for instance the Raptor engine
utilizes the full flow stage combustion
cycle engine and that was already
developed by the Soviets in the 60s um
for an engine called the Rd 270 and it's
makes sense like on paper 100% it makes
sense because you're basically
extracting the absolute
maximum potential of the chemical energy
in both propellants and you know at the
at the end of the day like you have to
be dumb enough to say we're going to try
using this thing because it's actually
really complicated to to do what they're
doing but at the same time like so are
so are Rockets like rocket engines
already stupid complicated so adding you
know 10 20% more you know pain in the
butt during the R&D if it's you know in
the long long long 20 30y year existence
or whatever you know like future of that
engine is that going to be worth it
obviously SpaceX said yeah I think we
can actually develop this this Raptor
engine so it's it's just interesting to
see the things that have been looked at
or even reusability you know like the
space shuttle was reusable it was fully
uh the upper stage you know the shuttle
itself the the Orbiter was you know I
mean that thing was for all intents and
purposes a reusable rocket now did it
live up to its expectations not
necessarily so it left a lot of bad
taste in people's mouth on the the ideas
of reusability so for SpaceX to kind of
come back into the room and on the table
and say we're going to use a reusable
rocket specifically we're going to do a
fully reasonable rocket you know a lot
of people are even still today A lot of
people are going yeah yeah you're not
going to be able to do that even today
even today so like long term you're not
going to be able to reuse at
scale yeah but yeah definitely I think
the number of people that are saying
that today is is a small portion of
those that were saying that type of
thing five years ago you know when Elon
did that announcement in
2016 um for the its it was very very
aspirational and people were just like
yeah right you know and there's a large
number of people that had the fact ual
reasons to to think that and do that you
know um at the time they had only landed
like two Rockets or something you know
when they did that or maybe three it was
very small number uh when they announced
that actually they had just lost a
couple months prior they just lost amo6
so they like they were still this young
blossoming company and to come in and be
like we figured out reusability and now
we're going to go full scale and make
the world's biggest most heaviest most
powerful rocket ever and we're going to
fully reuse it and it's going to go to
Mars was just pretty out there like it
really was and yeah you know it's all
about perspective but now again we're
coming up on 100 consecutive Landings of
an orbital class rocket that's you know
45 MERS tall 3.7 met wide like this
thing is huge weighs 20 metric tons even
empty when it's Landing that thing's
already huge so seeing the success of
that I think people are now more like
well okay maybe maybe there is actually
the opportunity to be fully reusable
that's definitely probably the biggest
constraint that I think has been
questioned that isil yep and then of
course like the broader one of cost of
bringing down cost uh that it's able to
you're able to kind of bring down cost
so much that this something like
colonizing Mars or many trips to Mars
would be a possibility that's people
don't even that seems so far out that
they don't even have time or give effort
to questioning it but it's the implied
questioning can you really do that many
launches actually do it can you actually
do it yeah it's it's looking I think
it's one of those things where you look
at the curve you know you look at like
10 years ago that was ridiculous yeah
following this curve if SpaceX goes from
you know two years ago launching I don't
remember what it was 40 times to 60
times to 100 times this year is their is
their amount and if we just keep
extrapolating that out if they maybe not
that exponential maybe it goes more
linear whatever what's 20 30 years like
the amount of stuff we can put on orbit
and and the potential we have to do
things like absolutely now I don't want
to put a time frame like you know yeah I
think but you got to think it's we're
increasing the number of launches we're
increasing the amount of things in space
we're increasing the amount of payload
on orbit that's probably not going to
decrease anytime soon and
therefore eventually like the idea of
goin