Winged vs. propulsive landing of rockets

[TomcatViP]

You can hear Buzz Aldrin saying "Picking some dust"

Takeoff method is specified in the video and the text that comes with: oblique

The velocity imparted to dust particulates is a function of the thrust needed on landing, hence the mass of the lander and the the gravity of the celestial body.
You can see when probes land on meteors that the danger is real with recirculating dust particulates and rocks that are lifted and follow a sub-orbital trajectory (being "airborne" for many cycles). Invariably, you'll have the same concerns with massive rockets landing on the moon repeatedly... Until someone build a landing pad strong enough and stays there to maintain it!

The Lunar STOL landing method exposed in that video (The Squirrel Moonwalk) is there just for that, as to make cargo handling operations much simpler.
The problem is quite similar on earth with off-field landings (ex. military). I use the Brownout term on purpose.

 

[martinbayer]

You can hear Buzz Aldrin saying "Picking some dust"

Takeoff method is specified in the video and the text that comes with: oblique

The velocity imparted to dust particulates is a function of the thrust needed on landing, hence the mass of the lander and the the gravity of the celestial body.
You can see when probes land on meteors that the danger is real with recirculating dust particulates and rocks that are lifted and follow a sub-orbital trajectory (being "airborne" for many cycles). Invariably, you'll have the same concerns with massive rockets landing on the moon repeatedly... Until someone build a landing pad strong enough and stays there to maintain it!

The Lunar STOL landing method exposed in that video (The Squirrel Moonwalk) is there just for that, as to make cargo handling operations much simpler.
The problem is quite similar on earth with off-field landings (ex. military). I use the Brownout term on purpose.

No wonder I had no idea what you were talking about - Aldrin actually said "*kicking* (NOT picking) some dust", see for example the transcript at https://www.vaticanobservatory.org/sacred-space-astronomy/kicking-dust-apollo-11-memories-part-1/! Aldrin's remark seemed however more like an observation than a concern, and obviously they made it safely down to the surface after all through that dust storm .

I concur that at least your video is oblique - for whatever reason it is heavily censored, see my screengrab below. It cuts the description as well as the diagram off right were it looks to become interesting, so would you mind adding a plain text description of your concept (and the full screen video as well, for that matter)?

 

[TomcatViP]

I have to admit that It's too hard for me to tell with certitude what Aldrin said. Here is a screen grab of the footage discussed above.

Data are proprietary but the acceleration curve tells the viewer that there is nothing spiking above 5g (unit is cumbersome)

A descriptive text can be accessed by clicking on "Show more":

Lunar gravity and atmosphere
Lunar regolith with related properties
50km/h approach speed - STOL glide slope
Boosted recovery (2x burn with variable boost setup simulated)
Max impact load on structure: 3g
No attitude thruster needed
Simulated landing mass: 285t (metric)
Landing distance: 100m
Near tangential burn only
No brown-out condition
Dust and rocks free landing (risks of puncturing damages reduced)
Horizontal attitude for cargo operations

The rocket is then raised partially for an oblique takeoff (dust & rocks damages free)
Earth STOL is possible with only partial lift (ex. 70% results in a 300m landing on sand)

 

[martinbayer]

View attachment 664919
I have to admit that It's too hard for me to tell with certitude what Aldrin said. Here is a screen grab of the footage discussed above.

Data are proprietary but the acceleration curve tells the viewer that there is nothing spiking above 5g (unit is cumbersome)

A descriptive text can be accessed by clicking on "Show more":

Lunar gravity and atmosphere
Lunar regolith with related properties
50km/h approach speed - STOL glide slope
Boosted recovery (2x burn with variable boost setup simulated)
Max impact load on structure: 3g
No attitude thruster needed
Simulated landing mass: 285t (metric)
Landing distance: 100m
Near tangential burn only
No brown-out condition
Dust and rocks free landing (risks of puncturing damages reduced)
Horizontal attitude for cargo operations

The rocket is then raised partially for an oblique takeoff (dust & rocks damages free)
Earth STOL is possible with only partial lift (ex. 70% results in a 300m landing on sand)

What kind of infrastructure is required for the partial raising of the craft, and will it fit on board of the first lander, or will it have to be prepositioned by a dedicated one way lander?

 

[TomcatViP]

Integrated. Landing mass minus Payload times the relaxed gravity give us favorable parameters for this.

 

[RanulfC]

@RanulfC : VTHL does not works on the moon?

Check this:

https://www.secretprojects.co.uk/threads/artemis-moon-program.32471/post-484360

It also can work on earth (300m landing distance). So far I haven't run a Simulation for Mars.

It's not easy but I did point out Kraft Ehricke's concept for the "Slide Out" lunar lander

And NASA looked at that for the Apollo program, not that it doesn't "work" it's that it's far from easy or really something you want to do on a regular basis. There have been a number of "horizontal" landers for the Moon and Mars, (been looking into Boeing's "not-a-Starbug" lander concept recently ) as it brings the crew and cargo closer to the surface and makes ingress and egress vastly easier. The biggest issue is the designs don't really lend themselves to single payload launches on 'conventional' boosters as well as a vertical, in-line design.

Neat stuff btw

Randy

 

[publiusr]

Now wings will not produce lift -of course- in the vacuum above the Moon...but something the shape of Buran would be a good design for a slide out-no rolling to the side. This craft is a sliding erector launcher--the wide footing is your launch deflector. A flap to keep debris down. Jack up the footing for a shed to keep micrometeoroids from damaging anything parked beneath. Even in the vacuum of space...wide surface areas can be handy. Modularity not had with rockets that must all look like telephone poles.

 

[TomcatViP]

Not specifically related but would be interesting to see the merits and drawbacks in that context:

View: https://youtu.be/thS5oSwhRF8

 

[publiusr]

That's the best thing Elon has done---putting rockets back on the table in other roles besides sat-launch....the first to do so since Bono/Medaris, etc.

You might even have something like this as a shelter

MTKVA

MTKVA

www.astronautix.com

MTKVP: Glushko’s Opening Gambit

What it was: A fairly sophisticated 1973-76 attempt to square the circle between the ballistic capsules favoured by Russian spacecraft designers and the Space Shuttle analog being demanded of them …

falsesteps.wordpress.com

И.Афанасьев. МТКК с вертикальной посадкой

This concept I have been trying to find for years:

https://www.frassanito.com/work/images/planning02.jpg

This project ever have a name?

 

[TomcatViP]

It's hard to think at such a massive vehicle landing under parachutes with all going well in 100% of the time. Parachute recovery is not that reliable.

 

[publiusr]

If it is cargo only you can still salvage things. It is what we slide out the back of planes.

Getting back to the idea of slide-out landings on the Moon, I see the fuselage on a sliding foot being a frame on shocks.

Assemble the wedge like segments into a larger pad for things like Starship…and combine the small TEL frames into a big one. Starship will be the workhorse, but I see Old Space as doing specialty craft…one-offs…oddball craft that can work in concert with what Musk is trying to do.

Titan…not Mars…has my interest. Those hydrocarbon seas are screaming to become plastic. Bypass asteroids…build fuel bases and work back to asteroids. Starships on Titan become tanks once more.

 

[RanulfC]

No, Merlins do not need "lot of inspection and maintenance between flights"
80 successful landings means they are "very controlled and easy"
Falcon does not use hydrazine.
TEA/TEB is easier to use than hydrazine. It does not require SCAPE gear.

Yes they do require a lot of inspection and maintenance, it takes about two days to inspect and refurbish the engines according to SpaceX. It takes less than 10 minutes to inspect and certify a jet engine.

80 landings is not "controlled and easy", several MILLION take offs and landings is "controlled and easy".

Falcon DOES use hydrazine it's part of the RCS propellant

TEA/TEB is about the same as hydrazine. While they don't wear the SCAPE gear specifically for the TEA/TEB they wear anyway since part of the pre-flight is inspection of the RCS and TEA/TEB system. It's just about as toxic and DOES require special clothing and handling gear including a ventilator or mask.

The "moving a light house" is an idiotic comment publiusr made about Starship and its booster.
Hover slam bothers the engines no more than entry does.
And wrong, powered landing for boosters has nothing to with landing on other bodies. It was specifically for booster reuse, because parachuting without entry burn didn't work.

VTVL boosters will always be cheaper than VTHL booster because of the minimalistic structure. The amount of mass needed to make a expendable booster a VTVL is much less than a VTHL

The booster IS moved in a vertical position from the barge or landing pad, then laid down onto a truck and driven back to the maintenance facility. You hook up a tow-bar and drive a horizontal lander with wheels back. Hover-slam exposes the engines to high heating with little cooling. They specifically fire an engine on reentry to keep the reentry heating away from the engines.

VTVL is far from the most efficient means of landing. Parachuting the booster back has been shown to work quite well it was just that SpaceX made the rookie mistake of disregarding aerodynamic entry forces and not having any plan for vehicle control on reentry, hence they lost control and broke up. And I'll point out that it was Musk himself who stated that the powered landing was specifically to prepare for such landings on Mars since you can't use "wings" on Mars to land.

Your assertion of expense is not supported, turning an 'expendable' booster into a glide back booster has been extensively studied and it's actually more efficient and economical than rocket powered VTVL. (Parachute and ocean recovery is actually the cheapest and easiest) The Air Force looked into turning the expendable Titan II stage into a reusable booster, (apparently many of them used for space launch actually survived reentry and were found floating "mostly" intact) and found that the payload hit for anything other than parachutes and a water landing or wings was to high. Again, SpaceX takes about a 15% payload hit with landing down-range and more than that with boost-back and landing.

Randy

 

[RanulfC]

@martinbayer : thanks, I wasn't aware of Ehricke's Lunar lander concept.

In anyway, however, the idea here is different. We are here in the terminal phase of the landing after the vehicle has been slowed down and is guided for terminal touchdown (remember Apollo video when the LEM begin the final approach gliding down the surface before landing vertically).
The goal of the Squirrel Moonwalk is to allow a massive rocket (285 metric tons) to land in a short distance (100m) without blasting half the moon surface back into orbit (no brownout condition) with its inherent hazard of damages from puncturation, offer a better way to handle cargo operations (the lean down attitude at rest), minimize fuel consumption and offer a similar rock blast free takeoff.

As I noted they looked at this for Apollo since the original plan was for Direct Ascent so that the lander would be a LOT taller than what we got.
See:

And



The idea is still around with things like the United Launch Alliance's Dual Thrust Axis Lander (DTAL), or the NAR Horizontal Lander concept up to the more recent EAGLE, (European Advanced Gear for Lunar Exploration) which is a favorite of mine

The "Squirrel Moonwalk" is an interesting concept

Randy

 

[RanulfC]

You can hear Buzz Aldrin saying "Picking some dust"

Takeoff method is specified in the video and the text that comes with: oblique

The velocity imparted to dust particulates is a function of the thrust needed on landing, hence the mass of the lander and the the gravity of the celestial body.
You can see when probes land on meteors that the danger is real with recirculating dust particulates and rocks that are lifted and follow a sub-orbital trajectory (being "airborne" for many cycles). Invariably, you'll have the same concerns with massive rockets landing on the moon repeatedly... Until someone build a landing pad strong enough and stays there to maintain it!

The Lunar STOL landing method exposed in that video (The Squirrel Moonwalk) is there just for that, as to make cargo handling operations much simpler.
The problem is quite similar on earth with off-field landings (ex. military). I use the Brownout term on purpose.

No wonder I had no idea what you were talking about - Aldrin actually said "*kicking* (NOT picking) some dust", see for example the transcript at https://www.vaticanobservatory.org/sacred-space-astronomy/kicking-dust-apollo-11-memories-part-1/! Aldrin's remark seemed however more like an observation than a concern, and obviously they made it safely down to the surface after all through that dust storm .

In context, (and you folks are probably past this by now ) the concern is not so much for the vehicle itself but any and all Lunar operations that might be impacted (literally and figuratively ) by the dust plume. Apollo 12 found that their landing had blasted a lot of dust into Surveyor 3 and there was a LOT more dust, (easier to see due to the lighting during that landing) than expected.

More landings (and take offs) will result in more dust and debris being kicked up which is a concern

Randy

 

[RanulfC]

Now wings will not produce lift -of course- in the vacuum above the Moon...but something the shape of Buran would be a good design for a slide out-no rolling to the side. This craft is a sliding erector launcher--the wide footing is your launch deflector. A flap to keep debris down. Jack up the footing for a shed to keep micrometeoroids from damaging anything parked beneath. Even in the vacuum of space...wide surface areas can be handy. Modularity not had with rockets that must all look like telephone poles.

Your problem with something like Buran, (other than getting it to the Moon in the first place ) is that it's not really a good 'shape' for landing on such a surface. The 'good' news is the wings will nicely deflect the dust and debris back down onto the surface. The bad news is it's going to help deflect dust and debris back down onto the surface by having it deflect off the wings and lower surface which it going to sand blast them into junk

Randy

 

[RanulfC]

That's the best thing Elon has done---putting rockets back on the table in other roles besides sat-launch....the first to do so since Bono/Medaris, etc.

You might even have something like this as a shelter

MTKVA

MTKVA

www.astronautix.com

MTKVP: Glushko’s Opening Gambit

What it was: A fairly sophisticated 1973-76 attempt to square the circle between the ballistic capsules favoured by Russian spacecraft designers and the Space Shuttle analog being demanded of them …

falsesteps.wordpress.com

И.Афанасьев. МТКК с вертикальной посадкой

MTKVA was about as big an object as you'd ever want to try and land with parachutes, pretty much if one failed they would lose the vehicle.

This concept I have been trying to find for years:

https://www.frassanito.com/work/images/planning02.jpg

This project ever have a name?

Not really a 'project' but an idea for a biconic CEV concept that made the rounds. Blue Origins biconic capsule concept was close to this design.

Randy

 

[publiusr]

Here is a question on a way to soften vertical landings.

Imagine, if you will…landing legs that are also plungers. The harder the piston is jammed home…the more hypergolics are pushed out as thrust to soften said landing.

No computer controls needed as everything is self correcting…good for smaller landers perhaps?

 

[TomcatViP]

@martinbayer @RanulfC

New 4 min long Video that includes some of the results of the discussion:
(edited)

View: https://youtu.be/kfUFfCP5bEg

Data curves at the end of the video!

 

[TomcatViP]

Here is a question on a way to soften vertical landings.

Imagine, if you will…landing legs that are also plungers. The harder the piston is jammed home…the more hypergolics are pushed out as thrust to soften said landing.

No computer controls needed as everything is self correcting…good for smaller landers perhaps?

The problem in that is that you are reliant on the nature of the material you are landing on: if the ground is too soft, your landing won't be arrested as the plunger won't detect any contact (imagine splashing in water for example).
Apollo LEM had flexible sensing probes that are more easily adaptable to a wide variety of soils.

 

[robunos]

Assuming that there is sufficient atmosphere to allow for aerodynamic landing, I would have thought that it all comes down to weight and cost.
What's lighter and cheaper ? The extra structure needed for a winged landing, or the extra fuel and tankage for a propulsive one . . .
Just my two pence worth.


cheers,
Robin.

 

[publiusr]

If you can catch the booster, you need neither wings nor legs.

Now, I still like a giant, scaled up Saturn IB where very long legs fit between the tanks—-no danger of punch throughs there.
Here, you might have a booster not need a pad…launch anywhere. Put a winged stage on top of that maybe…or vice versa. There is no one-best-way.

 

[martinbayer]

Assuming that there is sufficient atmosphere to allow for aerodynamic landing, I would have thought that it all comes down to weight and cost.
What's lighter and cheaper ? The extra structure needed for a winged landing, or the extra fuel and tankage for a propulsive one . . .
Just my two pence worth.


cheers,
Robin.

Operational reliability and safety, turnaround effort, and (for a reusable vehicle) durability/design life are also important considerations. Although they also influence cost, they are decision drivers in their own right as well, especially for crewed vehicles.

 

[Dilandu]

Propulsive landing have one enormous advantage: the stresses in the rocket structure always are in one direction. While winged rocket subjected to "vertical" stresses during takeoff, and "horizontal" while aerodynamic landing.

 

[TomcatViP]

@Dilandu : Longitudinal and vertical stresses

But see above in the video how stress can be mitigated during a lunar landing ~1g (earth equivalent) for example. Some parallels can be made for a similar landing on earth.

Otherwise, the loads involved during the landing phase of an Aircraft like rocket or Space ship are also generally low (as any passengers might know) when everything goes to plan and certainly milder than any boosted vertical landing.

The mass of the wings is more of a problem if we are comparing only the terminal landing phase.

 

[publiusr]

If you catch a rocket from the top…you might stove it in by accident. I think one reason Musk wanted a pure rocket centric approach was that meant he could avoid airfields and the blue suits that come with them

 

[TomcatViP]

A derivative of the above described landing technique, Earth operations, FOB (sand): landing speed 160km/h - landing distance 250m

 

[martinbayer]

A derivative of the above described landing technique, Earth operations, fwd OB (sand): landing speed 160km/h - landing distance 250m

View attachment 666024

What would be the potential advantages of landing on a random unprepared and likely remote terrestrial sandy touchdown site (desert or beach) as opposed to the plethora of already existing landing strips with even minimal infrastructure and logistics access around the globe?

 

[jeffb]

A derivative of the above described landing technique, Earth operations, fwd OB (sand): landing speed 160km/h - landing distance 250m

View attachment 666024

What would be the potential advantages of landing on a random unprepared and likely remote terrestrial sandy touchdown site (desert or beach) as opposed to the plethora of already existing landing strips with even minimal infrastructure and logistics access around the globe?

Larger margin of error?

 

[martinbayer]

A derivative of the above described landing technique, Earth operations, fwd OB (sand): landing speed 160km/h - landing distance 250m

View attachment 666024

What would be the potential advantages of landing on a random unprepared and likely remote terrestrial sandy touchdown site (desert or beach) as opposed to the plethora of already existing landing strips with even minimal infrastructure and logistics access around the globe?

Larger margin of error?

With readily available GPS navigation and touchdown precision of even vertical landing stages a la SpaceX sufficient to stick the landing on a comparative floating postage stamp, I'd accept that argument for our Moon and any other celestial bodies, but not for Mother Earth itself .

 

[Zoo Tycoon]

A derivative of the above described landing technique, Earth operations, fwd OB (sand): landing speed 160km/h - landing distance 250m

The nice thing about landing on sand is it’s high energy absorption during the roll out. Hence no need for heavy brakes, but the disadvantage is sands poor load bearing capability. However I guess the basic empty weight is pretty low so when the sums are done it might just come out ahead. Wheels and brakes are essential when wings are added to a vehicle and unless something clever is done they’re always gonna add mass. I once designed a skid and the clever bit is that the runway becomes part of the heat absorbing mass and a big one to boot.

Space.X’s “catch during a vertical propulsive landing” is likely failure intolerant;- one bad landing (or take off) has the potential to damage a lot critical essential operating infrastructure which is expensive/time consuming to replace . I’m surprised how close the tank farm is to the launch platform compared to others, and most others don’t have such a large prime mover filled with so much propellant. They’ve had plenty of landings go wrong (deep respect for their persistence) and at least one bad take off so I guess they’ve the background knowledge to figure out the optimum ground equipment separations…. but it’s only human to make mistakes.

 

[TomcatViP]

A derivative of the above described landing technique, Earth operations, fwd OB (sand): landing speed 160km/h - landing distance 250m

View attachment 666024

What would be the potential advantages of landing on a random unprepared and likely remote terrestrial sandy touchdown site (desert or beach) as opposed to the plethora of already existing landing strips with even minimal infrastructure and logistics access around the globe?

I used sand here as it was the closest material on earth related to the earliest study for STOL landing on the moon. It is also widely representative of FOB conditions worldwide. It has also good cyclic compressive strength. Any 300t vehicle repeatedly landing on the same patch of dry land will scrap the surface layer quickly in most location.
The main advantages of this kind of landing stand in being non-dependent of landing site infrastructures for cargo handling operations and generating a dust and debris safe zone for the landing vehicle while offering short field landing characteristics (land nearly anywhere).

It's mainly something in line with ASC Rocket cargo AFRL program.

 

[TomcatViP]

Forgot to say, Gif image above is for a landing boost of 2.6MN for a 300t landing vehicle!
Boost time is less than 10s.
Max deceleration load is 2.5G (can be reduced with a longer landing roll).
I wonder how that would compare with SpaceX Falcon 9, Falcon Heavy and Starship in a cargo resupply mission.

(and don't forget to watch (and like if relevant) the 4min video above to give me some energy and feedback for the one related to earth STOL)

 

[tequilashooter]

Only reason why I hear that winged is better than vtol for re-usability is it uses half the amount of fuel for payload and the other half to re-land(is that correct?)But I rather think that the decisions Roscosmos makes are really important such as even though Rogozin stated that Yenisei would be 4 times cheaper than SLS they than postponed their current design for methane engines to go further cheaper. Falcon 9 sells for 50 million minimum and they gave price estimates that they can sell it for 15 million dollars each based on 6 re-uses and refurbishment costs of the 1st stage. Although Amur a methane re-usable VTOL rocket has a smaller payload with 22 million dollars you can use 2 launches to have more payload and lower costs than Falcon and they state 300 re-uses like Musk states 1000 re-uses on starship. I am assuming that the Amur can still further lower its costs based on the recovery of 1st stages like the falcon 9

Perhaps the failure of baikal makes people suggest VTOL is a more simple approach and why the Amur was chosen. But one year ago a design bureau was created to create winged rocket designs. Therefore we are getting rocket designs like the krylo-sv which characteristics of engine are still unknown and until recently the Irkut rocket which uses methane with a weight of 25 tons. Besides wings I hear both designs will also use the assistance of parachutes and aircraft .engines for recovery. This makes me assume that winged rockets are better used for smaller payloads like a starlink or oneweb satellite which is why the irkut or krylo-sv were not VTOL rockets. I can't say for sure that they will create heavier wing based rockets or how much better they would be.

This sort of reminds me of the director of Energia being interviewed about methane rockets saying that there are even space companies going along with the idea to use methane rockets on Mars. And than was asked later what they would use for deep space travel like to Mars he states nuclear reactors and electric engines for better efficiency than LNG fuel(90%methane) sort of in a low key way making it look like Musks approach was idiotic in his interview which might raise fear here again about his self driving teslas in 2014, electric trucks working better than diesel despite battery weight, supersonic VTOL chairs and the Vegas loop. But I will still give the company a benefit of a doubt since thunderf00t(huge space x critic) has not bashed the use of methane inMars approach since he does have a PhD in chemistry.

 

[publiusr]

This is why….even if Bono’s saucer design wasn’t meant to be serious….I still want some billionaires to explore it. M-1 was powerful and partially tested…does not use the super greenhouse gas methane that suffers from supply chain problems anyway. Hydrogen engines like RD-0120 had simpler development than Glushko’s kero-burners. Wing loading may be less than on Big Onion that was to land on water…where Sea Dragon was going to get its propellant from through nuclear electrolysis. Fusion is making in-roads, and the magnets now coming for it are said to be able to lift an aircraft carrier…or maybe a huge superconducting LH2 filled disk shaped HLLV down a track. The ultra wide payload is perfect for dishes, optics. SPSS infrastructure, etc.

Though Bono may have not been serious, a lot of things are coming together to make large hydrogen filled lenticular designs a really if funding can be had. Everything is pointing in the direction of HTOHL…and a mag ramp a true “stage zero.”

Every recovery is Sully in the Hudson with flying saucer Catalinas.

Float it back over your mag ramp. No landing gear. No cherry pickers or super-cranes…no robot arms.

Tug boats, ropes, ramps and reactors.

No trucks—no airfields.

 

[Orionblamblam]

This is why….even if Bono’s saucer design wasn’t meant to be serious….I still want some billionaires to explore it.

So, rather than expend limited resources on systems that could work and be useful, you want them wasted on things that were acknowledged by the guy who came up with them as non-competitive at best, jokes at worst?

Why not trampolines?

How about this compromise: let's have billionaires and governments work on developing things that willa ctually work cost effectively, and when space launch gets cheap and easy enough that the design of launch vehicles is less about engineering than about art, *then* go and spend billions on saucers and similar ridiculousness.

 

[publiusr]

Now, had I advocated Starship-Super Heavy back twenty years ago on starship modeler-before either of us knew Elon from Adam-wouldn't you have called that ridiculous too? What a difference a hundred billion dollars makes. What I don't get is why so many space websites struggle- I would give you and our moderator here a milion each. Aerospace historians need funding. At any rate...I hear Stucky has allied himself with Blue Origin. They don't need a stick-and-rudder man as they are in the propulsive landing camp-but he might get Bezos to see another way...engineers are cowed by Bezos...but here the brashness of a pilot might be just what is needed to blow past Jeff's secretary and get Bezos out of this-well-funk. The future of winged spaceflight might well be in Stuckey's deft hands. The key is to be abrasive enough to get noticed-without getting fired. Kirk had his shot. Now we need to get Blue's attention....and you don't do that by being the meek 'blue shirt' Picard.

 

[TomcatViP]

Graph added (Speed [mm/s] and vertical acceleration [mm/s²]):
landing speed 100mph, slope angle 5°, Landing distance 200m, Surface material: sand, Span 55m, Cl 3.0 (landing configuration)

 

[Orionblamblam]

Now, had I advocated Starship-Super Heavy back twenty years ago on starship modeler-before either of us knew Elon from Adam-wouldn't you have called that ridiculous too?

Twenty years ago Starship might have seemed aggressive technologically. Twenty years ago Bono's saucer was thirty years into being a bad idea. An added twenty years hasn't made it any better. Any technological developments that may have made it somewhat less awful have made saner design options *better.*

 

[publiusr]

Now a saucer is wider…and that would reduce heating a bit would it not? Starship…for its size…is comparatively narrow..

A recent paper looked into 304 stainless as part of a TPS:

AIAA Aerospace Research Central

More recently Rice University’s George R. Brown School of Engineering had a breakthrough: “Engineers develop flexible, self healing material to protect steel from the elements.” Steel was put in sea-water for a month with no corrosion. Big Onion didn’t have that. Nuytco recently was allowed access to classified submarine steel secrets for their Exosuit 2000.

Combine that with the new magnets…and I could at least see flatter craft that can use the ocean and tugboats instead of gantries and cranes.