Starship “EP2P” (Earth Point-to-Point) Discussion

[ecarfan]

The entire history of space travel has had 18 in flight fatalities out of 536 people in space (including sub-orbital). Total fatality events was 4 out of 319 launches, and in each of these the root cause was identified and mitigated in future launches.

I am certain that is a much better safety record than the first 319 powered aircraft flights (by “powered” I mean by some sort of mechanical engine).

It has been interesting to read this thread as the discussion has developed. I recognize that there are significant obstacles to making EP2P flights a reality. I believe regulations will evolve to accommodate them and I am confident there is a significant market. With a ticket price between economy and business, the attraction of reducing transit time from 12 to 14 hours to 30 to 40 minutes will be a powerful draw. I think that the time spent at the “spaceport” before boarding will be comparable to the time we now spend at the airport (about 2 hours minimum for an international flight).

Loading passengers into a BFS shouldn’t take longer than loading a trans-oceanic jet. In fact it could take less time since for a BFR flight passengers shouldn’t be allowed to take carryons; all luggage will have to be very securely stowed in the cargo bay for safety and to avoid damage. Passengers won’t be allowed to use laptop computers or tablets during the flight and I question whether they should even be allowed to keep their phones with them since the flights are so short and you want to minimize the objects that they can have access to that might get loose in the microgravity phase and then end up who knows where in the cabin when the descent phase begins. It seem to me that passengers won’t be allowed to leave their seats during the flight and there will be no bathrooms available. Disembarkation should be fairly fast compared to any long haul jet flight.

Reducing the BFS turnaround time to a few hours will be a serious challenge. It sounds like the plan is to have a BFR (1st stage) available at the landing site and then the BFS will be placed on it. Elon talked about landing directly on the launch mounts.

 

[mongo]

I like the no carry on idea, but that would not be popular with executives with laptops or other expensive items. Perhaps individual storage cubbies? If all the seats are the same, then boarding should be faster. Although, it will be strange depending on the seat orientation for launch. Perhaps the seats start upright and rotate back for launch?

With a ticket price between economy and business, the attraction of reducing transit time from 12 to 14 hours to 30 to 40 minutes will be a powerful draw.

Or in the case of the new New York to Singapore route, 20 hours.

Reducing the BFS turnaround time to a few hours will be a serious challenge. It sounds like the plan is to have a BFR (1st stage) available at the landing site and then the BFS will be placed on it. Elon talked about landing directly on the launch mounts

From things I've seen, I think BFR does a return to base and lands back on the launch mounts. BFS lands next to it and gets craned back on top. Based on cabin door position, de-embarking may happen after the restacking.

Given the reduced performance requirements, the fuel and oxygen will not need to be sub chilled, so fuel loading can occur earlier in the process.

 

[e-FTW]

I am certain that is a much better safety record than the first 319 powered aircraft flights (by “powered” I mean by some sort of mechanical engine).

It has been interesting to read this thread as the discussion has developed. I recognize that there are significant obstacles to making EP2P flights a reality. I believe regulations will evolve to accommodate them and I am confident there is a significant market. With a ticket price between economy and business, the attraction of reducing transit time from 12 to 14 hours to 30 to 40 minutes will be a powerful draw. I think that the time spent at the “spaceport” before boarding will be comparable to the time we now spend at the airport (about 2 hours minimum for an international flight).

Loading passengers into a BFS shouldn’t take longer than loading a trans-oceanic jet. In fact it could take less time since for a BFR flight passengers shouldn’t be allowed to take carryons; all luggage will have to be very securely stowed in the cargo bay for safety and to avoid damage. Passengers won’t be allowed to use laptop computers or tablets during the flight and I question whether they should even be allowed to keep their phones with them since the flights are so short and you want to minimize the objects that they can have access to that might get loose in the microgravity phase and then end up who knows where in the cabin when the descent phase begins. It seem to me that passengers won’t be allowed to leave their seats during the flight and there will be no bathrooms available. Disembarkation should be fairly fast compared to any long haul jet flight.

Reducing the BFS turnaround time to a few hours will be a serious challenge. It sounds like the plan is to have a BFR (1st stage) available at the landing site and then the BFS will be placed on it. Elon talked about landing directly on the launch mounts.

This all sounds fair enough.
It is now too late for my “But will my giant carry-on fit in the overhead?” joke.

For such short flights, I agree that there is no point in having your devices with you. It will be a hard sell to separate humans from their phones though. But then again, they may be permanently implanted by then. Almost completely joking...

 

[RDoc]

If (false) then

<pretty much anything>​

else

<reality>​

end

 

[PhantomX]

I am still trying to figure out how a rocket transport is going to be cheaper than a supersonic airplane transport system?

BTW, regulator only makes things harder when new technologies are introduced. Take a look at the new regulations and requirements that were introduced when Boeing and Airbus decided to put composite wings into commerical passenger transports. FAA and other regulators will take the most conservative approach first when dealing with new technologies in commercial transportation of human beings. I really don't see exception to that when it comes to BFR EP2P.

 

[ecarfan]

I am still trying to figure out how a rocket transport is going to be cheaper than a supersonic airplane transport system?

A company named Boom (odd choice for a name, in this case) is trying to build a commercial supersonic plane but it will be small, only 55 seats according to their website. The company claims ticket prices will be like “business class”. Boom - Supersonic Passenger Airplanes

Supersonic Planes Are Mounting a Comeback—Without That Earth-Shaking Boom
Supersonic jets may be about to make a comeback (Paywall)

I question how a plane that small will be able to offer ticket prices that low.

Gwynne’s main argument seems to be that a BFR could fly anywhere on Earth so quickly that the same spaceship could be used many times per day, which cuts costs, with tickets being less than business class. Obviously there are huge challenges that have to be overcome to make that a reality. But she seems like a very reality-based person.

I suspect that a BFR could accommodate several hundred passengers per flight. So that would help reduce ticket prices After all, it has the interior volume of a jumbo jet. Supersonic aircraft in contrast have very limited interior volume. The Concorde was a 2+2 seating arrangement, and the Boom aircraft appears to be a 1+1 seating arrangement.

Interesting times!

 

[mongo]

I am still trying to figure out how a rocket transport is going to be cheaper than a supersonic airplane transport system?

Tl;dr
Built BFR/BFS, fly on earth for some profit, use to send BFS send to Mars, go back to making money on earth hops.
Vs
Build BFR, use to send BFS to Mars.

Like @ecarfan said, the available volume and cargo mass is much higher along with more flights per day.

Also, SpaceX needs to make the BFR/BFS for the Mars missions, but they can only launch every 22 months or so. Their choices are:

• Massively parallel manufacturing that finishes all rockets just in time for launch
• Serial construction with finished goods waiting 0-22 months for launch.
• Serial construction with BFR used for earth hops until being set to Mars. (BFSs might be unique, but could be reused shells with updated interiors).

SpaceX is going to have hardware sitting around regardless, so unless Earth hops wear out the BFR, there is little vehicle amortization needed in the earth hop ticket cost. Plus, it is subsidizing flight/ durability/ cycle testing.

There are major advantages to not having them sitting around (assuming you even had enough space for them too).

This does assume that they will be sending more than just a couple ships to Mars.

The BFRs can also cycle themselves through the various landing sites, so the one that flew New York to Hong Kong one week can be the same one that launches a satellite the next week and refuels a BFS heading to the moon base the week after.

 

[Grendal]

I may have already mentioned this but I expect that SpaceX will splinter off a separate company for doing Earth hops. That company will buy BFS's and maybe BFR boosters from SpaceX for the Earth transportation system.

 

[N5329K]

I am still trying to figure out how a rocket transport is going to be cheaper than a supersonic airplane transport system?

I don't think it ever will be cheaper, company prognostications aside. I fully expect to be at the controls of my flying car before regular, passenger-carrying BFS flights become anything like routine.
Though it will be a chuckle to be proven wrong!
Robin

 

[Model 3]

So that would help reduce ticket prices

One more thing: I suspect that the BFS don't need any pilot's, and with a shorter flight time I suspect they need fewer flight attendants.

 

[N5329K]

Barf bags will be known as "boarding passes."
Robin

 

[ecarfan]

One more thing: I suspect that the BFS don't need any pilot's, and with a shorter flight time I suspect they need fewer flight attendants.

All BFR “piloting” will be done from the ground-based mission control room, and I think that will require more highly trained staff than a commercial jet has on board.

As for flight attendants I agree, not many will be required. For a 30 to 40 minute sub-orbital flight where the passengers stay strapped in there is essentially nothing for flight attendants to do beyond getting everyone seated and buckled up. And once they are strapped in, passengers won’t be allowed to get out of their seats during the flight. Medical emergency? Too bad. Too little time between boost phase and landing phase to do anything about it.

 

[PhantomX]

Tl;dr
Built BFR/BFS, fly on earth for some profit, use to send BFS send to Mars, go back to making money on earth hops.
Vs
Build BFR, use to send BFS to Mars.

Like @ecarfan said, the available volume and cargo mass is much higher along with more flights per day.

Also, SpaceX needs to make the BFR/BFS for the Mars missions, but they can only launch every 22 months or so. Their choices are:

• Massively parallel manufacturing that finishes all rockets just in time for launch
• Serial construction with finished goods waiting 0-22 months for launch.
• Serial construction with BFR used for earth hops until being set to Mars. (BFSs might be unique, but could be reused shells with updated interiors).

SpaceX is going to have hardware sitting around regardless, so unless Earth hops wear out the BFR, there is little vehicle amortization needed in the earth hop ticket cost. Plus, it is subsidizing flight/ durability/ cycle testing.

There are major advantages to not having them sitting around (assuming you even had enough space for them too).

This does assume that they will be sending more than just a couple ships to Mars.

The BFRs can also cycle themselves through the various landing sites, so the one that flew New York to Hong Kong one week can be the same one that launches a satellite the next week and refuels a BFS heading to the moon base the week after.

This addresses non-recurring costs related to the hardware, but what about the recurring operating costs such as fuel and ground op? A Cathay Pacific business class round trip flight costs between LAX and HKG $6000, so a one-way EP2P flight of same trip with 100 passengers will need its operating cost less than $300,000 to compete on price. Assuming average weight of 200lb per passenger + luggage, that'll be $300K to lift 20,000 lb of payload into space, or $15 per pound of payload. I know it doesn't need to go into orbit, but that's still quite an ambitious cost target!

 

[PhantomX]

All BFR “piloting” will be done from the ground-based mission control room, and I think that will require more highly trained staff than a commercial jet has on board.

As for flight attendants I agree, not many will be required. For a 30 to 40 minute sub-orbital flight where the passengers stay strapped in there is essentially nothing for flight attendants to do beyond getting everyone seated and buckled up. And once they are strapped in, passengers won’t be allowed to get out of their seats during the flight. Medical emergency? Too bad. Too little time between boost phase and landing phase to do anything about it.

Again, going back to certification requirements. FAA states all commercial passenger flights need 2 attendants for the 1st 100 passengers, and additional 1 for every extra 50 passengers after that. This is for evacuation purpose, so unless SpaceX can convince FAA to rewrite its rule, then they'll need to follow the flight attendance requirements.

Same regarding number of pilots. The 2 pilots rule is a mandatory requirements, so going full autonomous will require a lot of work to convince FAA to change the rules.

 

[ecarfan]

so a one-way EP2P flight of same trip with 100 passengers will need its operating cost less than $300,000 to compete on price

I’m pretty sure that these BFR EP2P flights will carry far more than 100 passengers, given that the BFS pressurized volume will be similar to a jumbo jet.

Again, going back to certification requirements. FAA states all commercial passenger flights need 2 attendants for the 1st 100 passengers, and additional 1 for every extra 50 passengers after that. This is for evacuation purpose, so unless SpaceX can convince FAA to rewrite its rule, then they'll need to follow the flight attendance requirements.

Regulations can change over time to accommodate new technologies.

 

[mongo]

This addresses non-recurring costs related to the hardware, but what about the recurring operating costs such as fuel and ground op? A Cathay Pacific business class round trip flight costs between LAX and HKG $6000, so a one-way EP2P flight of same trip with 100 passengers will need its operating cost less than $300,000 to compete on price. Assuming average weight of 200lb per passenger + luggage, that'll be $300K to lift 20,000 lb of payload into space, or $15 per pound of payload. I know it doesn't need to go into orbit, but that's still quite an ambitious cost target!

Falcon 9 can put 50,000 pounds into low earth orbit. Dragon capsule weighs 10,000 pounds. So 40k net, or 200 passengers. Adjust for non LEO insertion, size of BFR, and you are talking a lot of tickets per flight.
BFR has an LEO spec (per wikipedia) of 330,000 pounds. Chop that in half for BFS and cabin comfort, and you are still talking 800 people.
Keeping the $6,000 ticket, putting 300 people on a flight is $900,000 gross per leg.

Methane ($0.36 gallon/ $0.085 per pound) is currently cheaper than jet-A ($2.21 a gallon), and liquid oxygen is also low cost ($70 a ton).
Interview with Muller from SpaceX.

One million pounds of CH4 is $85,000. And one million pounds of O2 is $35,000. The engines use 3.6 lbs of O2 per lb of CH4, so the cost of one million pounds of fuel is $46,000. BFR weighs about 6 million pound full, say it's all fuel that is $280,000. BFS holds a little over a million pounds, call it $60k, total fuel load for orbit is sub $350,000. (If I did my conversions right).

The really great thing is that with only electricity, water, and CO2 (collected from power plants or other means), they can make their own fuel. With solar, once the plant is set up, the fuel can be even lower cost.

 

[oneday]

I may have already mentioned this but I expect that SpaceX will splinter off a separate company for doing Earth hops. That company will buy BFS's and maybe BFR boosters from SpaceX for the Earth transportation system.

My guess is that Elon will use his old domain name of x.com for eXploration bookings. Earth hops and eventually flights to mars and other places.

 

[bxr140]

There is no reason to be doing in atmosphere maneuvering that isn't planned and modeled before the flight starts. Any alternate landing sites will be mapped out with orbit changes required and you will declare your landing spot and commit to it once you fire a deorbit burn.

I’m not so sure that’s how it will play out, for two reasons:

1. While certainly planned in advance as contingency, from a mass efficiency perspective I can see atmospheric maneuvers using control surfaces as a primary method of changing trajectory to an alternate landing site.

2. Many of these hops will be sub orbital. It simply doesn’t make sense to go orbital to get from from HK to Singapore, for instance. Even directly on the opposite side of the world is probably more mass and time efficient to just huck the thing through a ballistic arc. Maximum altitude and/or speed does not dictate whether an object is in a sustainable orbit.

 

[mongo]

1. While certainly planned in advance as contingency, from a mass efficiency perspective I can see atmospheric maneuvers using control surfaces as a primary method of changing trajectory to an alternate landing site.

BFS as shown has minimal lift/ control surfaces, it's meant less as a glider, and more as aero-braking (even the slight wing was an unwanted, but required, trade off for multi-atmosphere usability). I'm thinking they can adjust velocity in the flight to shift the landing point, if needed. Start burn sooner: land short, delay landing burn: land long. Rotate a few degrees first, land to the side.

 

[ecarfan]

Many of these hops will be sub orbital.

Based on what I have heard Elon and Gywnne say, all BFR EP2P flights will be sub-orbital.