Value proposition of Starship Earth-to-Earth

[mikelepage]

Hi all,

EDIT: I'm modifying the original post here in response a mod suggestion to merge with this older thread here
https://forum.nasaspaceflight.com/index.php?topic=45376.0 on SpaceX plans to transport passengers around the world through orbital flight.  Gwynne Shotwell has claimed costs will be somewhere between that of an equivalent economy class and a business class air ticket for the same trip.

TLDR: My main question is in response to the "how does Earth-to-Earth get started" thread.  Will PTP travel be valuable - not because it can get to the destination quickly - but because it makes suborbital space tourism obsolete (see my 3 questions at bottom of thread)?

State of things:
*Dragon 2 DM-1 due to launch NET March 2019.
*Yusaku Maezawa has funded SpaceX to the tune of several 100s of million USD, to help complete the #DearMoon project in 2023 (effectively an Earth-to-Earth flight with a detour  )
*Raptor engine has now achieved flight thrust/pressure requirements.
*Starship hopper flight program planned during 2019.
*Starship orbital flights aiming for 2020.

My additions:
*Rumours of Starship Super Heavy class sea platform under construction? This is assumed to be of a jack-up barge configuration, which are plausible in up to 100m water depth.
*My calculations for noise around Starship Super Heavy launches suggest they're likely to be marginally worse than Falcon Heavy.  Exclusion zones are estimated at around 16km (10 miles) and, depending on atmospheric attenuation, noise levels are likely to be unacceptable if the launch pads were within 65km (40 miles) of most major cities.
*While SSH is potentially launch-able from KSC 39A/Brownsville, the likelihood of a pad failure during initial launches suggests they will do all test launches from their sea platform, minimising risk to Falcon 9/FH operations.
*Because such sea platforms could be built to spec, one could see them being produced relatively quickly (say, 1-2/year) and installed around the world as spaceports. 

I've just been having a look at http://map.openseamap.org/ which gives a good idea of sea traffic, and it can be configured to show the depth of 100m around coastlines, all around the world.  It's because of this, as well as the noise-exclusion zones, that I think most platforms will be some distance away from major cities (which usually tend to have major sea ports), and using ferries to send people out to the launch platforms will be impractical in most places.  IMO it's better to use large-capacity helicopters such as the Boeing-Vertol 234 (civilian version of the Chinook CH47) which can transport up to 44 passengers at one time, at much higher speeds than any ferry.

Some questions come to mind:
1) Where will the first passenger-ready launch platform in the US be? Outside the US?
2) Is speed of transit the most important thing? If a 24 hour transit (e.g. New York to Melbourne) is only reduced to an 8 hour transit, but passengers get to experience 4 orbits (6 hours) of zero G, is that a more saleable proposition?
3) What about this as a way to make suborbital tourism obsolete? It's true that some (most?) people won't want to actually land in a different country, so you could have two Starships launch less than an hour apart into the same orbit, dock to each other, transfer those passengers who want to travel to the other spaceport, and then each Starship lands again at the pad from which it took off.  (Launching in pairs as standard practice could also mean long term improvements in safety - you'd always have a backup craft in case of any Columbia-type accidents on the way up).

[guckyfan]

I wonder how they plan to get the cost that low. I recall that Gwynne Shotwell mentioned 100 passengers.

I have always argued against SSTO. Elon Musk has said Starship is SSTO capable but it is not worth it.

We know the Raptor has more thrust than needed. So they could make the tanks larger, reducing the passenger volume to the tapered nose cone, still plenty for 100 passengers. Also the orbit can be very low, maybe 150km, still good for a few orbits. 100 passengers may need 20t payload. I can imagine that setup, without the Super Heavy, would make operations much easier and bring cost down. Is this idea feasible in any way?

[su27k]

Yeah, I'm a big fan of the SSTO for P2P idea, but with all the recent changes it's hard to say how feasible this is. But at the very least they can use a shortened SuperHeavy for P2P, for example the 19 Raptor SH proposed in the other thread, this would reduce both the noise level and fuel consumption, so win win.

[mikelepage]

I wonder how they plan to get the cost that low. I recall that Gwynne Shotwell mentioned 100 passengers.

I have always argued against SSTO. Elon Musk has said Starship is SSTO capable but it is not worth it.

We know the Raptor has more thrust than needed. So they could make the tanks larger, reducing the passenger volume to the tapered nose cone, still plenty for 100 passengers. Also the orbit can be very low, maybe 150km, still good for a few orbits. 100 passengers may need 20t payload. I can imagine that setup, without the Super Heavy, would make operations much easier and bring cost down. Is this idea feasible in any way?

I do wonder whether those cost estimates are anything more complicated than taking the expected cost of propellent per flight (~$200k), adding one 1/1000th of $300 million per SSH ($300k), and dividing by 100 passengers to get a $5k ticket price.  Simplistic, but perhaps not reasonable to do anything more at the moment. 

I am fairly sure that PTP by SSTO with a modified Starship might be a technically solvable problem that could be optimised for, they're just not going to do it, based on comments by Musk and previous SpaceX history of optimisation choices.  They're building an interplanetary vessel, and Earth-to-Earth is a side project.

[mikelepage]

Yeah, I'm a big fan of the SSTO for P2P idea, but with all the recent changes it's hard to say how feasible this is. But at the very least they can use a shortened SuperHeavy for P2P, for example the 19 Raptor SH proposed in the other thread, this would reduce both the noise level and fuel consumption, so win win.

The wise heads on this forum always caution against the "lego rocket" mentality, but seeing as SpaceX has already identified a 19 raptor Super Heavy (does that make it just a "Heavy"?  ) as part of their development pathway, maybe this is a real possibility for use in PTP applications.  Noise exclusion zones would drop to only a little more than that of Falcon Heavy, and environmental impacts would be proportionately lower. 

I don't think they would shorten the booster, as that would require retooling the factory and affect all the landing infrastructure  - e.g. require another crew access arm at different height.  But it could be a way of flight testing new boosters in a less demanding regime before you add the extra engines.

[M.E.T.]

I’m not a point to point fan, as I question the value of saving a few hours at the cost of an order of magnitude higher risk of death, but to answer the cost per ticket question, were they not planning to increase it to maybe 300 passengers for these short trips?

The 100 passenger limit related to the Mars voyages where a lot of supplies and equipment had to be brought along too. If you cram 300 people in, it reduces the cost per person by a factor of three.

[RobLynn]

shuttle had about 500km long boom path during last stages of re-entry.  Nimbys won't permit that over their heads if it's frequent.

[guckyfan]

I’m not a point to point fan, as I question the value of saving a few hours at the cost of an order of magnitude higher risk of death, but to answer the cost per ticket question, were they not planning to increase it to maybe 300 passengers for these short trips?

The 100 passenger limit related to the Mars voyages where a lot of supplies and equipment had to be brought along too. If you cram 300 people in, it reduces the cost per person by a factor of three.

It is an option. But Gwynne Shotwell mentioned the 100 passenger number for those flights. I imagine it is not easy to sell that many tickets at these prices.

[Cheapchips]

Shotwell also mention that they plan to fly multiple times a day, maximising vehicle use.  There's quite a lot of logistics and cost wrapped up in passenger and tanker trips to the platform before you get to the rocket bit. 

[Slarty1080]

I can' see Point to Point happening any time soon. First they need to get Starship/Superheavy operational, that’s going to take a few years. Then they will need to kit out a Starship for the DearMoon mission and even more importantly get Starlink up and running by 2024.

When that's starting to earn money the profits will go into debt repayment and the multitude of things they will need for Mars, more unmanned precursor missions, orbital refuelling, increased cadence, a sea launch platform or two perhaps, pressurized rovers, Mars grade ECLSS, extra SH/SS's, vacuum raptor, Mars power options, ISRU development and stuff and things they will need on Mars like suits etc etc etc.

IMO Musk only views point to point as a means to an end. For Musk Mars settlement is an end in in itself, so if the money keeps coming in from Starlink IMO he will just ratchet up the number of Starships going to Mars. But if money is still an issue and point to point is seen as a key means to increase revenue then perhaps in the 2030's they might get round to it.

[dubya]

As others have said if P2P happens at all, it is a LONG way down the road.
Assuming all the development works out I would expect to see orbital and lunar space tourism first. As a path to P2P space travel will probably follow the same path as air travel did though. That is, cargo first. Not sure how large the market is for ultra time critical cargo is however.

[Ludus]

It would get started from the minimum infrastructure which is a single passenger Starship with a single launch facility, so orbital Space Tourism. Presumably Blue Origin and Virgin Galactic would have already been doing suborbital flights with a handful of people for $200k a ticket. Virgin Galactic is more about the branding than the tech so they might operate the booking for Starship (it would kill the suborbital biz anyway). We know that SpaceX is building a passenger Starship configured for SpaceTourism for the Moon flyby anyway and that’s what would be used.

100 passengers at $200k a ticket would bring in $20M per flight which is probably enough. It would probably stay in orbit for awhile and offer various entertainments and amenities.

Add another launch facility on the other side of the world and there can be point to point cruises as well and exploratory quick no frills flights, testing the business market.

It might also do occasional repeats of the Moon flyby Cruise at much higher prices that test orbital propellant transfer. I suspect SpaceX’s plan for this is aggressive enough that 50 tourists on a Lunar Cruise could standby and watch NASA’s astronauts on Orion’s first historic mission to the LOP-G

[Slarty1080]

I wonder how they plan to get the cost that low. I recall that Gwynne Shotwell mentioned 100 passengers.

I have always argued against SSTO. Elon Musk has said Starship is SSTO capable but it is not worth it.

We know the Raptor has more thrust than needed. So they could make the tanks larger, reducing the passenger volume to the tapered nose cone, still plenty for 100 passengers. Also the orbit can be very low, maybe 150km, still good for a few orbits. 100 passengers may need 20t payload. I can imagine that setup, without the Super Heavy, would make operations much easier and bring cost down. Is this idea feasible in any way?

I do wonder whether those cost estimates are anything more complicated than taking the expected cost of propellent per flight (~$200k), adding one 1/1000th of $300 million per SSH ($300k), and dividing by 100 passengers to get a $5k ticket price.  Simplistic, but perhaps not reasonable to do anything more at the moment. 

I am fairly sure that PTP by SSTO with a modified Starship might be a technically solvable problem that could be optimised for, they're just not going to do it, based on comments by Musk and previous SpaceX history of optimisation choices.  They're building an interplanetary vessel, and Earth-to-Earth is a side project.

I doubt the calculations are that simple. The life span of the Starship ealy versions will be much less and later versions will be unproven until some have flown a lot of missions. You may also want to check your sums there, its never going to cost $5.

[Lemurion]

I don't see point-to-point coming any time soon largely because I don't think anyone has a handle on the regulatory environment. Once they figure out what's legally possible, they can work on solving the rest of the issues.

[spacenut]

I too do not think point to point will begin anytime soon.  Maybe 20-50 years.

One, SS/SH will be very busy with lunar, Mars, a fuel depot (maybe), LOP-G deliveries (maybe), visiting ISS (If it is still operational when SS begins operations, and Starlink II launches.

Two, it has to shoe extreme reliability doing the above.

Three, the Air Force/Army might consider it for troop transports with supplies at various hot spots like Bono's Rombus idea from the 1960's.  This would encourage civilian flights. 

Four, a nation this point to point would serve would have to build facilities for launching and landing.  This would run the gambit for safety, reliability, timeliness, etc.  The location of these facilities would have to be several mile away from a heavily populated area, off shore, etc. 

Five, Concord failed because of cost to operate.  Tickets were expensive in comparison to say a 747.  Then there is jet lag problems. 

Therefore 20-50 years into the future. 

[Lee Jay]

I’m not a point to point fan, as I question the value of saving a few hours at the cost of an order of magnitude higher risk of death,...

An order of magnitude?  Try 5 orders of magnitude.

[Coastal Ron]

I too do not think point to point will begin anytime soon.  Maybe 20-50 years.

At the iteration rate SpaceX has, the Starship as we understand it today won't be flying anymore in 20 years. It will have been replaced by something else.

One, SS/SH will be very busy with lunar, Mars, a fuel depot (maybe), LOP-G deliveries (maybe), visiting ISS (If it is still operational when SS begins operations, and Starlink II launches.

All of those objections seem to be based on the idea that there can only be a limited number of Starship vehicles. Which we know is not the plan, since Elon Musk plans to ramp up the number of vehicles that can launch to Mars every launch window. In other words, they will build as many as there is demand for.

Five, Concord failed because of cost to operate.  Tickets were expensive in comparison to say a 747.  Then there is jet lag problems.

There is a market risk for this, but unlike the Concord, which was only used for passenger point-to-point transportation, the Starship has many other uses and SpaceX will have the ability to experiment with this service without betting the company on its success.

Therefore 20-50 years into the future.

I don't see how any of your objections have solutions out more than just a couple of years - or never do. Which is why I don't think "20-50 years" has any basis in reality.

[Lar]

(fan) 100 passengers is way too low. 500 is more realistic.
(mod)
1 - OP, did you crosslink this with the original thread? Can you PM me a compelling reason not to merge them? Name change isn't compelling. We can rename the original thread.
2 - Everyone else, please make sure you're not just rehashing arguments from the original thread.

[Beratnyi]

I will try to calculate the passenger capacity of Starship when traveling point-to-point. If we divide the observation deck and the cargo hold into two floors, then there will be 10 decks in the ship. The area of each deck is about 55m2-in total 550m2, which exactly corresponds to the area of the A380 decks! Airbus accommodates 853 passengers in economy class, which means $ 5,000,000 for launch / 853 = $ 5862 for a ticket!

[spacenut]

There may be a point to point with mixture of passenger/cargo.  Especially cargo that may be time sensitive.  Point to point will only take about 45 minutes.  Say one extra hour to fuel/load cargo.  Then one hour to unload get sensitive cargo unloaded and on its way to destination.  That is about 2.4-3 hours anywhere in the world vs about 12+ hours from say America to South Africa or Australia. 

I do know he will keep manufacturing many SS/SH's.  Infrastructure to handle them will be a huge cost factor unless governments or other private companies help build the infrastructure to handle take-offs and landings, plus metholox cooling storage and systems.  Initially this would limit locations to say 3-5 miles offshore of liquid methane shipping cities and receiving locations.