Project Bases to Land Planet Hopper Class star ships

[TCR_500]

I'm going to build several bases to hold a Planet Hopper class shar ship. One on Earth (4 runways, 2 4-mile, 1 5-mile, 1 2-mile), one on Mars (1 runway, 1 1-mile) and one on the Moon (1 runway, 1 1-mile). The one on Earth will be a complete space port ready to carry almost any vessel. The one on the Moon can carry the Planet Hopper class star ship and smaller crafts. The one on Mars will just be a landing site for a while while the base is constructed. I've completed 3 of the 4 runways on the Earth base, although I'm going to have to put more texture segments on the large runways. It's comming along pretty well.

 

[garyw]

So show us some screenshots then.

Pictures are worth 1,000 words.

 

[T.Neo]

I'm going to build several bases to hold a Planet Hopper class shar ship. One on Earth (4 runways, 2 4-mile, 1 5-mile, 1 2-mile), one on Mars (1 runway, 1 1-mile) and one on the Moon (1 runway, 1 1-mile). The one on Earth will be a complete space port ready to carry almost any vessel. The one on the Moon can carry the Planet Hopper class star ship and smaller crafts. The one on Mars will just be a landing site for a while while the base is constructed. I've completed 3 of the 4 runways on the Earth base, although I'm going to have to put more texture segments on the large runways. It's comming along pretty well.

Firstly, I'm begging you to use metric. It will make your life much easier, and is an overall better measurement system.

Secondly, runways on the Moon are utterly pointless, as they are intended for atmospheric craft. The Moon has no atmosphere, and landings are done vertically with rocket engines. The same is the case for Mars, although the thin atmosphere does allow for some atmospheric flight.

 

[tl8]

So show us some screenshots then.

Pictures are worth 1,000 words.

^Agreed^

 

[Urwumpe]

But you can't land on Mars properly at least not without propulsive support (Too high ground speeds for producing lift). The VECTOR approach would be the closest you can get to Earth like conditions (but the AOA would be close to 90°), but well... I guess TCR 500 knows more about physics than we do.

---------- Post added at 02:32 PM ---------- Previous post was at 02:31 PM ----------

So show us some screenshots then.

Pictures are worth 1,000 words.

Agreed!

 

[ThatGuy]

Much easier when you start with metric
(Estimates)
4 mile= 6.5 km
5 mile= 8 km
2 mile= 3 km

Also, 8 km/5 mi is quite a long runway. Most are under 8000 ft/ 2.5 km

 

[TCR_500]

Ok, I'll have a screenshot by the end of the week of the Earth base. For the runways on the other planets, they are just to allow for some forward speed tollerance. You'll need to have the hovering thrusters fired or you'll over-shoot the runway. You might run out of runway anyways if you don't fire the retro thrusters after you make contact with the surface.

The Earth base is completed enough so an aircraft/spacecraft can land on any of the landing pads, or the three runways I have completed.

By the way, the Surface Base Wizard is giving me some problems. Something about "Run-time error '9': Subscript out of range". Is there a limit to the number of sub segments a runway can have? Because I was able to build the base, I just can't open it. Well, I was until I changed the configuration of the runway.

 

[garyw]

Why the end of the week? Sounds like you have already done a lot of dev work completed for the Earth base - go on, just a sneek peak!

Maybe raise a bug report with the author of the Surface base wizard?

 

[T.Neo]

Ok, I'll have a screenshot by the end of the week of the Earth base. For the runways on the other planets, they are just to allow for some forward speed tollerance. You'll need to have the hovering thrusters fired or you'll over-shoot the runway. You might run out of runway anyways if you don't fire the retro thrusters after you make contact with the surface.

Have you even landed at Brighton Beach on the Moon?
No runway is needed whatsoever. And any lateral velocity, forward or otherwise would be canceled out just before landing. Remember, that the Moon has no atmosphere. Lunar craft don't fly like airplanes.

And Star Wars physics isn't real.

 

[Sky Captain]

For Mars you will need a looong runway and your tires are likely to explode from excessive speed. XR5 needs 5 km to take off like a plane (with help of RCS) from Mars. Heavier craft with less thrust to mass ratio will need even longer runway.

 

[TCR_500]

I know that the space crafts fly differently in space than they do an atmosphere. Some can't fly like an aircraft even in an atmosphere. I did a test landing at the moon base I started building and I had to make sure that I didn't overshoot the runway, or land too hard or too fast.

I already have taken tire pressure into account. The tires on a Planet Hopper class starship are going to be thicker that other aircraft/spacecraft. And it's going to be layered. This will allow for faster landings as one of the layers are blown off on impact (mabey), but I wouldn't recomend landing at more that 1.5 m/sec verticle velocity. Plus, land with too much forward velocity, you'll over shoot your landing target anyways.

Ok, I'll get a screenshot out as soon as possible. I'll also have a video out showing me landing on a runway on the moon (once I get the orbiter replay converted to something like AVI). I've put the lunar base at a position that should be ideal for flight back to Earth.

And I don't get any physics from star wars.

 

[Artlav]

Now, why is a runway totally pointless on the Moon?
For things like Earth-Moon shuttles you'd likely to have the same approach vectors, so instead of wasting reaction mass slowing down to full stop, a ship may only slow down enough to hover onto the runway, and use the brakes to kill the rest of the velocity.

Since wheels will not likely stand a 1-1.5 km/s speed, something like ablative sleds might work better.

Lithobraking, survivable kind.

 

[ex-orbinaut]

...And it's going to be layered. This will allow for faster landings as one of the layers are blown off on impact (mabey), but I wouldn't recomend landing at more that 1.5 m/sec verticle velocity....

Concorde?

Now, why is a runway totally pointless on the Moon?
For things like Earth-Moon shuttles you'd likely to have the same approach vectors, so instead of wasting reaction mass slowing down to full stop, a ship may only slow down enough to hover onto the runway, and use the brakes to kill the rest of the velocity.

Since wheels will not likely stand a 1-1.5 km/s speed, something like ablative sleds might work better.

Lithobraking, survivable kind.

It is a good point. However, I do have a question. What solution would there be for the reduced braking effectiveness due to the low gravity environment, in this case? The wheels don't "press down" as hard as on Earth, so would "lock up" easier, wouldn't they?

 

[Artlav]

What solution would there be for the reduced braking effectiveness due to the low gravity enviornment, in this case? The wheels don't "press down" as hard as on Earth, so would "lock up" easier, wouldn't they?

Um, long runway, wide sleds/wheels?

Maybe some kind of decelerator - a train on maglev moving at near-orbital speed that a ship "docks" to, then the former hits the magnetic brakes?

 

[Urwumpe]

Artlav: You are now going from the hundredth into the thousandth. :lol:

Cold mathematical fact is: The difference in fuel between a horizontal landing and a vertical landing on the moon, is exactly the fuel needed for slowing down from maximal horizontal ground speed to zero (Gravity losses don't apply, control losses are ignored as they are not comparable in any case).

If you land on the moon with 150 m/s horizontal speed, on a Deltaglider like vehicle, this means you just saved about 13 seconds of engine burn time that way. You may calculate yourself, how many percent fuel this is.

 

[ex-orbinaut]

Artlav,
Magnetic brakes sounds just the thing. Like the monorail technology. That more or less solves it. I have seen and got most of your excellent add ons, so I hazard to ask; could this be simulated accurately in Orbiter? The runway on the moon solution would save some retroburn and hover fuel, if you are arriving with low fuel already, as I tend to.

Just seen Urwumpe's post (posted while I was writing mine). I think the angle is that you would still have some forward velocity at touch down, maybe miniscule in comparison to what you have already lost, but it would be some help to get rid off that with an external system like magnetic brakes installed in the runway, for example. Avoids having those crucial minutes hovering up to the pad when you have low fuel. It was just a thought...

 

[RisingFury]

Artlav,
Magnetic brakes sounds just the thing. Like the monorail technology. That more or less solves it. I have seen and got most of your excellent add ons, so I hazard to ask; could this be simulated accurately in Orbiter? The runway on the moon solution would save some retroburn and hover fuel, if you are arriving with low fuel already, as I tend to.

Surface friction is implemented. So, you can "imagine" your magnetic breaks...

 

[ex-orbinaut]

Surface friction is implemented. So, you can "imagine" your magnetic breaks...

By conditionally "raising" the surface friction coefficient in the code, depending on the planet, maybe?

 

[Urwumpe]

Just seen Urwumpe's post (posted while I was writing mine). I think the angle is that you would still have some forward velocity at touch down, maybe miniscule in comparison to what you have already lost, but it would be some help to get rid off that with an external system like magnetic brakes installed in the runway, for example. Avoids having those crucial minutes hovering up to the pad when you have low fuel. It was just a thought...

Yes, and this is exactly what I modeled. Instead of touching down with vertical speed only, have some remaining horizontal speed, which you did not yet neutralize.

You only hover above the pad, if you have too much fuel. Landing on a runway or on a VTOL pad makes no difference in that case, except that you can hover if you go for a vertical landing, while you can't hover for a horizontal landing.

 

[TCR_500]

Magnetic Breaks? I never thought about that, but it does sound like a good idea. A lot of things are done with magnets. A magnetic field powerful enough will effect almost anything. And, a magnetic field can be simulated.

Break lockup is easier to accomplish with lower gravity, but most aircraft/spacecraft (at least that I know) don't have big enough break disks to lock up the wheels. However, since there is no atmosphere, I'd be more concerned with overheating the breaks than locking them up. On Earth, the wheels cool themselves down, which helps with overheating.

Upon review of the replay, I hit the runway at about 0.2 m/sec on the Moon. And just like I said in my previous post, here is the screenshot. I was in the Delta Glider when I took this screenshot. And, don't criticize that the airport is in the middle of the water. It's a fictional airport and the water is really the only place that I know is clear. Now to do the surface tiles to make it more like land.

And I did save some fuel by not using the retro thrusters when I landed. However, where I put the moon base is a spot where Earth is almost straight up. I may move it a little to make it straight up and to avoid any craters.