Hi it's me, Tim Dodd, the Everyday Astronaut!
Elon Musk recently announced SpaceX's plans to be able to transport people anywhere around
the world in under an hour, with MOST long distance trips taking less than half hour
using SpaceX's upcoming BFR rocket!
Hold on, what?
Anywhere on Earth in under an hour?!
That can't be possible, right?
Well today, we're going to look into the feasibility as well as some of the challenges
SpaceX will face trying to bring this concept to life.
We're also going to do a quick look back at history to see what other once thought
impossible modes of transportation are now a part of our everyday lives.
So, will the average citizen really be getting on top of a rocket and traveling anywhere
around the world in less than an hour?
Let's find out!
On September 29th, 2017, Elon Musk unveiled SpaceX's updated plans for their future
rocket the BFR or Big Falcon Rocket.
Now, despite this new version being smaller and more conservative than the version they
announced just last year, there was one aspect that is widely criticized as being too far
fetched and impractical - using the BFR as a high speed point to point transportation
service here on Earth.
So first off, let's do a really quick recap of what the BFR is in the first place.
If you want to get more in depth, make sure and check out my video titled "SpaceX's
crazy new plan to get to Mars, the Moon and anywhere on Earth."
The BFR is SpaceX's next generation rocket and spaceship whose ultimate goal is to send
humans to Mars to colonize it.
Yes, that really is the primary mission.
Some quick facts: Although it won't be the tallest rocket ever, coming in just behind
the Saturn V moon rocket, it is still massively tall standing at 106 meters or 347 feet tall.
It's also not quite as wide as the Saturn V but it maintains its massive 9m diameter
from the bottom to the top, only tapering at the very tip.
But the most record breaking aspect is thrust.
The BFR will be powered by 31 methane fueled Raptor engines which can produce a whopping
53 meganewtons of thrust at sea level, which is more than the 35 meganewtons of thrust
on the SaturnV.
Scientifically speaking is a crap ton of thrust.
That's enough power to lift 36 million bananas.
The key aspect that makes the BFR even remotely viable as a point to point transportation
service on Earth is the fact that the first and the second stage of the vehicle are designed
to be fully recoverable and rapidly reusable.
The upper stage or the spaceship portion is sometimes called the BFS or Big Falcon Ship
so we'll refer to the upper stage as the BFS from here out.
The BFS is designed to handle the heat of Mars atmospheric entry, as well as Earth reentry
and then it will land using a trio of Raptor engines to come to a soft and accurate tail-first touchdown.
SpaceX will have a ton of practice launching and landing the BFR and BFS as they foresee
using upper stages as fuel tankers to rendezvous and dock with a nearly empty BFS.
After the tanker refills the spacecraft, it will land back on Earth.
They might do this up to 5 times on some interplanetary missions.
So they will have an awful lot of practice landing both stages of the BFR and if they
can manage to do this reliably, why not start putting humans onboard?...
Well let's address some of the issues.
Let's talk about the feasibility of using a ROCKET as a transportation service.
There's several factors that come to mind including; reliability, passenger health and
safety, noise, economics and the legality of flying a rocket to and from different countries
around the world landing near highly populated areas.
First up: Reliability.
Can rockets really be reliable enough to be a viable form of mass transportation?
One of the major design aspects of the Space Shuttle was to make it airliner like, routine
and safe.
As a matter of fact after the first four test flights of the Space Shuttle, crew onboard
forwent wearing pressurized spacesuits and instead wore essentially a pair of blue coveralls
and a crash helmet.
They did this right up until the space shuttle's 25th flight when disaster struck with the
loss of Space Shuttle Challenger and its 7 crew members.
We're not going to get into why the space shuttle ended up being unsafe in today's
video, but I bring this up so we can reflect on the fact that NASA thought the Space Shuttle
would be so safe, it would almost be airliner like…
But this doesn't reflect modern day, right?
We've learned a lot since then, so let's take a look at SpaceX's track record on
their current workhorse rocket, the Falcon 9.
To date, the Falcon 9 has launched 43 times with 2 loss of vehicles, giving them a current
success rate of 95.5% compared to the Space Shuttle's 98.5% success rate.
Now one could argue that in the case of the SpaceX failures, had there been humans on
board, they would've probably would've been fine due to the presence of a launch abort
system, but that's actually the kicker here.
First off, the BFR doesn't appear to have a launch abort system and second in order
for mass transportation to be considered a viable option, you can't go losing 4.5%
of your rockets or 1.5% or heck, even one in a thousands failure rate would be far too high!
But, at the pace of SpaceX's launch cadence, they clearly seem to be getting the reliability
thing down and I would love to see SpaceX hit 99% success with the Falcon 9 by 2020.
Considering even in 1960, when airliners weren't nearly as reliable as they are today, there
was still an impressive 99.995% success rate, or a failure just once in every 20,000 flights.
And although there isn't good data from the very early days of airliners, it's still
safe to assume they were much more reliable than 99 percent.
Elon reiterated how important safety is when he answered questions on a reddit "ask me
anything" recently.
He mentioned that safety, "will be especially important for point to point journeys on Earth.
The advantage of getting somewhere in 30 mins by rocket instead of 15 hours by plane will
be negatively affected if "but also, you might die" is on the ticket.""
That being said, there's still hope.
For instance, take SpaceX's workhorse rocket engine, the Merlin 1D.
Due to the high pressure and stresses, its safe to assume that the rocket engine is the
most dangerous and the least reliable part of rockets, despite this, SpaceX has flown
435 Merlin engines and has only experienced ONE fail in flight, which was safely contained
and the flight was still a success.
That's getting pretty darn reliable.
Not only this, the BFS will have 3 engines for landing as opposed to the one engine that
lands the Falcon 9.
Also, despite the fact that landing the first stage of the Falcon 9 is still considered
to be experimental, SpaceX has managed to land 14 in a ROW.
It seems now that they've got it figured out, it's a pretty reliable system of recovery.
And the good news is that SpaceX continues to pick up its launch cadence, up from just
2 launches 5 years ago to hopefully 20 in 2017!
They're even planning on 30 launches for 2018 and they show no signs of slowing down.
This of course means that they'll have many chances to learn from anomalies and design
new reliability methods often.
With airliners flying multiple times a day for several hours, there's troves of data
to make aircraft safer, and now hopefully, we'll begin to see more reliable rockets
as the cadence picks up.
Not only this, but since SpaceX has successfully recovered so many first stage boosters, they've
been able to collect data and analyze their vehicle more than previously possible!
Which should lead to an even better and safer rocket.
There's one more factor to keep in mind.
That's the fact that SpaceX will be building the BFR from the ground up with full reusability
in mind.
This is different than current rockets that still share their heritage with expendable
launch vehicles.
They're currently made to be as light, high performance and inexpensive as possible.
The BFR overcomes some of these barriers with its sheer size, its massively efficient Raptor
engines as well as advanced carbon fiber construction.
One of the biggest issues with the space shuttle was having to inspect and replace the 20,548
different high temperature reusable surface insulation tiles that made up the heat shield
on the underside of the shuttle.
SpaceX's approach will be to mount heat shield plates directly to the primary talk
wall for simplicity and for being the most mass efficient method.
This should make for refurbishment and servicing quicker and easier.
Due to the fact that the BFS won't quite be getting up to orbital speeds on these suborbital
point to point hops, the reentry heating will be much less than the Space Shuttle, but it
will still probably be pretty high and will probably be a major factor in the viability
of this concept.
Due to heat increasing by velocity CUBED (not squared), it means if the vehicle comes in
just 10% slower than that of orbital velocity, it would receive 25% less heat on reentry!
If you want to learn more about the effects of reentry heating, I suggest you check out
my video titled "Can SpaceX reuse a second stage?"
So now what about the logistics of passenger safety?
Forget the reliability of the rocket, what are we going to do about having an 85 year
old grandparent experiencing 3 g's of acceleration for 7 minutes, followed by zero G's for
several minutes, followed by another 3 g's of deacceleration.
Forget puke bags, this thing is going to be a giant flying puke bucket!
Well, perhaps there's something SpaceX can do to lower the G forces and make the flight
more enjoyable.
In fact, Elon addressed this in a tweet stating, "Assuming max acceleration of 2 to 3 g's,
but in a comfortable direction.
Will feel like a mild to moderate amusement park ride on ascent and then smooth, peaceful
& silent in zero gravity for most of the trip until landing."
Elon went on further to talk about how the landing portion will be as low as 1.3 g's,
which is the same as the initial launch.
Since the BFR is capable of going into a high Earth orbit, it's safe to assume that the
BFR could still reach its destinations while throttling down the engines to provide a less
punishing ride to space.
Rockets experience gravity loss on ascent and when propulsively descending, so it is
more efficient to accelerate quickly.
But since these are suborbital hops, they won't require the full performance of the
vehicle and we could assume they can throttle down a little for passenger comfort.
I speculate that unlike airlines today, there would need to be a rigorous health and background
check in order to be a passenger onboard a BFR.
This is something that perhaps could be a yearly check up and a yearly background check,
but hopefully it wouldn't impede travel too much.
It surely might weed out a few people, but I suspect rocket travel isn't for everyone
in the first place.
Speaking of impeding travel.
One of the biggest points of criticism I've heard was the time it would take to board
a BOAT, yeah a BOAT, and then get all those passengers up on top of a rocket.
Well, first off, I genuinely can't believe they didn't show using a hyperloop instead
of a boat.
I mean this is the future after all.
If we factor in check in, security check, a 20 or 30 minute boat ride, an elevator,
boarding, fueling, and all that, there could easily be 2 to 4 hours of preflight for the
passengers.
So some flights might not even make sense, but obviously, the payoff becomes greater
and greater the further away your destination.
While we're on the topic of boarding, how will passengers sit?
My guess would be the seats will start upright and then they'll rotate back before launch
so passengers are on their backs.
Like this.
Maybe a little smoother than that.
How far out would the launch and landing pad have to be from a populated area for the sound
to not be an issue?
Let's use the Saturn V as a reference which was 91 db's at 10 kms or 6 miles away, and
considering the FAA defines significant noise as 65 decibels we'd want these launch pads
to be much further away than that.
If the pads were 38 kms or 24 miles out, the launch would be a much less noticeable 79
db's, but that's still pretty noisey.
To get down closer to 65 decibels, the launch pad would need to be nearly 160 kms or 100
miles away from populated areas….
Hope they still aren't planning on getting there by boat!
If you've ever tried to catch a rocket launch in person, then you're probably familiar
with the term scrub.
When a launch gets delayed for any multitude of reasons, whether it be mechanical, range
safety or weather, the launch is scrubbed for its next available slot, which is often
the following day or sometimes a few days later.
This is something that will just take time to improve.
For now, there's NO WAY you could rely on a rocket launch to get you to an important
meeting on the other side of the world, but with experience and time, hopefully scrubs
will be a thing of the past.
For instance, when SpaceX first started using super chilled propellant and oxygen, the industry
poked fun at them, saying it's impossible to master and they're just wasting their
time trying.
At first, it seemed like everyone was right too.
SpaceX would have scrub after scrub after scrub as they tried to perfect their prop
loading procedures.
As a casual (or obsessed observer), this period of time was frustrating and almost scary.
A lot of us fans wondered whether or not the others in the industry were right and that
perhaps SpaceX was getting greedy trying to squeeze too much performance out of the Falcon 9.
Well, fast forward to less than two years later and the Falcon 9 has been hitting every
launch on time lately without fuss.
No resets, no scrubs, nothing.
Smooth sailing.
Practice makes perfect and with SpaceX launching more rockets than anyone, they certainly are
getting better and better.
Now what about weather delays?
One fun note is weather might actually be less of a challenge for rockets in some ways
than it is for airliners.
A rocket would only be in the atmosphere for a minute or two and then from there on out,
it'd be smooth sailing.
So as long as the weather is good enough for launch, there should be no turbulence or weather
issues during your travel.
In fact, the Soyuz rocket can take off during storms, high winds, rain and snow.
Hopefully SpaceX will figure out how to make it so the BFR can take off in just about any
situation that an airliner would be able to take off in… but we'll see!
And although SpaceX isn't planning on using a launch abort system, they claim that they
can get to airliner like reliability and safety.
This would be an absolute must if there is an absence of an abort system.
It will probably take hundreds if not thousands of successful flights of the BFR before anyone
considers it a viable mass transportation method… but seeing how often SpaceX is launching,
perhaps this will be sooner rather than later.
So now we need to bring up cost.
With the Falcon 9 currently costing around 60 million per launch, it's hard for us
to picture a scenario where it would be even remotely affordable even the richest people
to fly on a rocket…
But with a fully reusable system, the launch cost will eventually just be the cost of some
fuel, some check ups and the occasional servicing, just like a jetliner.
And luckily for future ticket holders, the methane fuel that powers the BFR is a lot
cheaper than the RP1 fuel used by the Falcon 9.
According to Elon, he foresees the cost getting down to that of a full fare economy ticket
on today's airliners.
Although that seems VERY unlikely at this point in time, even if they can get it down
to say $20,000 per ticket, they still might have a valid business case for the ultra rich.
One more small detail is that it's currently illegal to fly a rocket from one country to
another due to rockets being able to deliver quickly deliver nuclear weapons.
But, this could likely change if it is seriously pursued.
And lastly, I think perhaps the biggest bonus is how many people would get to experience
the overview effect.
The overview effect is a an awareness reported by some astronauts and cosmonauts during spaceflight,
often while seeing the Earth from orbit or from the surface of the moon.
It refers to the experience of witnessing with your own eyes the reality of the Earth
in space, as a tiny and insignificant ball of life.
From space, nations borders disappear, the petty conflicts that divide people becomes
less important, and the ultimate desire to unite all humans becomes apparent.
To me, this unifying effect might be the most important reason we need the BFR.
So to summarize, I think its best thing we take a quick look back at history.
Once upon a time, only about 100 years ago, if you needed to travel from say Europe to
New York, you'd hop on board a ocean liner and 5 to 7 days later you'd arrive at your
destination.
A first class ticket would cost around $50,000 USD with the cheapest tickets being around
$172 in today's costs.
Now if you were onboard one of these ships and someone came up to you and said "In
just 40 years, you'll be able to do this same trip in around 6 hours for about $500"
you'd ask them "How much did you have to drink tonight?"
It would've been simply impossible to imagine a world a world where in just 40 years, the
average person would be able to fly on a jet powered airliner that would go across the
Atlantic Ocean.
Let's do this again with another moment in history.
On October 14th, 1947, pilot Chuck Yeager climbed aboard his Bell X-1 rocket plane and
broke through the sound barrier, something that most people thought was physically impossible.
Now despite this, in less than 30 years, you could purchase tickets on the supersonic jetliner,
the Concorde.
And although the Concorde was forced into retirement due to rising costs and low passenger
numbers, it does goes to show how quickly we can go from something being impossible
to something anyone with enough money can experience in less than 30 years.
Elon Musk seems to thrive off this type of nay saying.
People laughed when he said he was going to launch a liquid fueled rocket into orbit.
People laughed when he said he was going to dock with the International Space Station.
I was there when SpaceX rolled out the first Falcon 9 with landings legs for mission CRS-3
in 2014.
I heard the laughter of how silly it was to put landing legs on a rocket.
People are laughing now when Elon says we can go anywhere around the world in less than
an hour by putting people on top of the world's largest rocket… well I'm not a betting
man, but if I were, I wouldn't bet against Elon musk.
So what do you think?
Do you really think people will be boarding a rocket and getting anywhere around the world
in under an hour?
Take the poll and let me know your thoughts in the comments below!
That being said, make sure you're subscribed so you can join the discussion when we continue
to learn more about the BFR.
Also remember I live host SpaceX launches starting about 30 minutes before lift off!
So come ask questions and join in the conversation live!
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Tell a friend!
Thanks everybody, that does it for me.
I'm Tim Dodd the Everyday Astronaut.
Bringing space down to earth for everyday people.
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