Kinunir-class landing gear

[abomination]

Not quite as large but my 440t fast trader (cough corsair) has an extra set of 1g grav plates on base of the hull. Power is diverted to these for horizontal flight, so the main drives are reduced to 2g.

If you aren't using grav tech. What you are trying to do is overcome friction.Instead of an wheeled/tracked undercarraige how about some sort of frictionless surface? Like the top of one of those air hockey tables that used to be popular.

 

[leopard]

IIRC the tracked landing gear worked, was just a maintenance nightmare and the noise was supposed to be "impressive" to say the least.

Didn't go as far in anything I designed as an extra set of grav plates, what I did was "assume" the main drive could operate off axis at full power at a cost of churning out a lot of waste heat - thus only could only do it for a while to land/take off not for prolonged hovering - allows "rescue" type operations with GM defined longer term effects as an when required.

Craft take off vertically, but quickly move to horizontal flight to avoid the drive plates melting - ditto for landing, come in using forwards flight, "air stilting" to drop speed before a final vertical touch down.

Larger craft could be given a dedicated 1G drive if not a tail sitter for landing, military stuff that can burn to 6G won't overheat as much to drop off axis at 1G for landing or 1.1G for take off.

 

[DangerousThing]

IIRC the tracked landing gear worked, was just a maintenance nightmare and the noise was supposed to be "impressive" to say the least.

Didn't go as far in anything I designed as an extra set of grav plates, what I did was "assume" the main drive could operate off axis at full power at a cost of churning out a lot of waste heat - thus only could only do it for a while to land/take off not for prolonged hovering - allows "rescue" type operations with GM defined longer term effects as an when required.

Craft take off vertically, but quickly move to horizontal flight to avoid the drive plates melting - ditto for landing, come in using forwards flight, "air stilting" to drop speed before a final vertical touch down.

Larger craft could be given a dedicated 1G drive if not a tail sitter for landing, military stuff that can burn to 6G won't overheat as much to drop off axis at 1G for landing or 1.1G for take off.

I've always assumed that grave plates were designed for at least 1.5g and capable of being used for landing. If an air/raft can get to orbit on its grave plate, then I think a space ship should be able to use them for hovering for a reasonable period without melting down.

 

[McPerth]

I've always assumed that grave plates were designed for at least 1.5g and capable of being used for landing. If an air/raft can get to orbit on its grave plate, then I think a space ship should be able to use them for hovering for a reasonable period without melting down.

I agree that ships land on their grav plates, but I'm not so sure they are enough finely tunnable as to be used for taxing along the starport. I envision this more being done with landing gear, either wheels or tracks.

IMHO to assume they don't taxi once landed is to say starports have less landing capability than they could (and so quite inefficient).

 

[leopard]

Point in the overheat was simple, to provide a hook to cause damage if it got abused, nothing else really. In effect also a way to run the drive on "overload", requiring more power - thus a commercial trader is going to find it hard to hover with all guns blazing - but can trade firepower for the ability to hover/land etc at will.

Also as an aside allowed for craft to mount powered fans to cool the plates in atmospheres - hot down draft and a nice sound effect, plus the "pink pink" sound as they cool down after.

Pure Roleplay effects really combined with a bit of a hand wave.

Feeds nicely into space combat as well, "redline the drive!!" to try and escape - works for short bursts - military craft are assumed to have better cooling and be able to sustain that setting etc.


Also assumed something close to "ground effect" with the grav plates working much more efficiently at very low altitudes (as in a few cm ground clearance) from a high density surface - thus craft can "taxi" over a suitable roadway at lower power settings (still assume a craft is not silent though) - needs a suitable taxiway to support it.

Again a pure gaming effect to allow craft to work the way I wanted them to work at the time, on occasion players, being players found other inventive ways to use these abilities (overloading the drives on a customs cutter to melt its landing gear into the ground was a fun one)

 

[ashiruni]

Personally, I've always used a variation out of Bill Baldwin's Helmsman series.

Starports are always located on the coast-line to minimize over-land travel (because in his setting Grav engines are insanely loud). Once they get ground-side they've got essentially a 'grav pool', or a hangar-like apparatus with a high-powered antigrav that evenly distributes the antigrav effect where it's needed to make the vessel effectively mass-less and just hovers at the right height. Once you establish that, adding in a set of air-way stairs or something similar to let you (dis)embark is easy.

For the actual runway, the grav landing pad gradually increases the power-output (thus giving a bit of altitude to clear the landing facility) and the ship's own gravs take over.

As something of a side note: I don't see why, should you need a runway, you can't vary this idea a bit and have an entire strip of grav plating running down the length of the runway, with a higher-density and output at one end, and the lower on the side closest to the terminal. If you wanted to make it especially effective at breaking/accelerating, you could even toss them in at a 45 degree angle with the shorter angle facing away from the terminal. The grav ought to provide stronger pressure toward something coming toward the terminal, and a bit of an extra push to something leaving it. For emergencies, add a high-density bit of plating built into the terminal as a means of stopping anything that the runway's plating couldn't stop.

For parking, should you use that runway, just include some train tracks that go around to all the terminals, then you make a custom cargo-rig that has a set of grav plating built into the flat-bed train cars. With your ship effectively reduced to little or no mass, the train can easily move it along and can 'park' the ship by detaching the engine from the cars.

A slightly more practical idea, however, would be a more mobile grav plate, which you could do by either having a landing pad like arrangements that holds itself up on gravs and either lets something land on it directly, or has an appropriate arrangement (I'd suggest an outer wall) to prevent the vessel from sliding around on a grav plate that's highly powered enough to handle the ship. Should it be a problem, you could even park that sucker by landing it and just plugging it into the local power grid. Power costs would just be subsidized as 'expenses' for the landing fee.

All in, most of this is reasonable at most TLs, tho TL's lower than ten might have to import the gravs. I'm sure the Imperium wouldn't mind partially subsidizing the costs if they get access to it

 

[Doyle Hunt]

A lot of the above will determine if 3000 psi, 4000 psi or greater psi will last very long under use.
Of course footing and foundation and the ground make a lot of difference

I will not go into the Engineering aspect of concrete, but I will say that if done properly and poured correctly, concrete will last 1,000 of years (depends on the concrete material and of course environment.)

That life span is entirely speculative. As an engineer, I'm personally familiar with structures made of 3000 psi concrete that are well over 100 years old. Some intact, some patched repeatedly to keep them from crumbling to gravel. The oldest structure in the real world made of 4000 psi concrete is Bonnet Carré Spillway in Norco, LA. The Corps of Engineers invented 4000 psi concrete when designing that structure, which started design in 1928, and finished construction in 1932. So it's only 80 years old, but still in use today with no sign of damage to the concrete.

One important point to consider, concrete is NOT the load-bearing component of the runway. The true load-bearing component is the soil beneath the runway. The aggregate layers provide for drainage, and the concrete merely provides a surface that won't get torn up by the planes, fuel and fire trucks, etc. The concrete transfers the load to the aggregate, and thence to the soil.

If the soil is not adequate to support the load imposed on your runway, there are numerous solutions. Such as driving pilings about every 1.5m on center under the runway to provide the necessary load bearing, and incorporating grade beams into the foundation design.