1g Ships and Size:7 worlds...

[Spinward Flow]

The difference between Physics and Engineering (as illustrated by a joke)

Physicist: Assume a spherical chicken of uniform density-
Engineer: HOLD IT!

 

[Grav_Moped]

Traditionally, the spherical livestock is bovine, and frictionless.

 

[atpollard]

And now for something completely different ...

Using Third Imperium TL 12+ technology fusion tunnel a tube completely through the center of a Size 10 World. The landing pad at the Starport tips the ship and drops it nose-first into the tunnel where it accelerates at 1G towards the Center of the planet and is accelerated forward at 1.25 G by the Planetary Gravity (V = 2.25 G = 225 mm). Since the Diameter of the world is only 160 mm, the ship ends its Turn 1 vector 65 mm from the planet surface (in the 0.25 G band). Turn 2 the ship continues to accelerate at 1G (+100 mm) with no gravity applied based on the midpoint of the 225 mm vector and ends the turn 390 mm from the planet with a 325mm vector away from the world.

TL 12 Vertical launch from a size 10 world at 1G.

 

[Grav_Moped]

And now for something completely different ...

Using Third Imperium TL 12+ technology fusion tunnel a tube completely through the center of a Size 10 World. The landing pad at the Starport tips the ship and drops it nose-first into the tunnel where it accelerates at 1G towards the Center of the planet and is accelerated forward at 1.25 G by the Planetary Gravity (V = 2.25 G = 225 mm). Since the Diameter of the world is only 160 mm, the ship ends its Turn 1 vector 65 mm from the planet surface (in the 0.25 G band). Turn 2 the ship continues to accelerate at 1G (+100 mm) with no gravity applied based on the midpoint of the 225 mm vector and ends the turn 390 mm from the planet with a 325mm vector away from the world.

TL 12 Vertical launch from a size 10 world at 1G.

Keeping the tunnel from collapsing (especially as it penetrates the planet's molten core) is left as an exercise for the student.

 

[Grav_Moped]

Keeping the tunnel from collapsing (especially as it penetrates the planet's molten core) is left as an exercise for the student.

At a shallower angle, it can be used to transport burritos. (PBS.org)

 

[AnotherDilbert]

Like these …

A rocket that launches vertically?

Yes, if we have thrust > weight things are simple.


If we look at a real live smallcraft with supersonic performance that can land on and take off from commercial runways:

It apparently needed significant wing area. The fuselage is about 20 Dt and the wing area ~360 m².

 

[AnotherDilbert]

Using Third Imperium TL 12+ technology fusion tunnel a tube completely through the center of a Size 10 World. The landing pad at the Starport tips the ship and drops it nose-first into the tunnel where it accelerates at 1G towards the Center of the planet ...

By RAW you don't even need the tunnel. I don't think there is a specific rule preventing you from flying inside a planet...

 

[kilemall]

By RAW you don't even need the tunnel. I don't think there is a specific rule preventing you from flying inside a planet...

Pretty sure there was a default rule about planetary impact auto destroys the ship.

 

[AnotherDilbert]

Pretty sure there was a default rule about planetary impact auto destroys the ship.

Can you find it? I have been looking...

 

[mike wightman]

Instead of Concorde look at the wing area of the F104.

 

[AnotherDilbert]

This?

36 m² wing area for a mass of 24 tonnes, or 3000 m² per Free Trader.


Did you mean the F-104 Starfighter, the Widowmaker, the Lawn Dart?
18 m² wing area for 13 tonnes MTOW, or ~2800 m² per Free Trader.

Not very remarkable?


The Concorde used 360 m² for 185 tonnes, or 3900 m² per Free Trader. Not so different.

 

[Condottiere]

Swing wing.

Extended for maximum lift.

 

[mike wightman]

Yes I meant the F104 - failing eyesight and not reading what I posted

 

[mike wightman]

 

[Condottiere]

As I recall, one issue being stall speed, so establish if the spacecraft first can take off and not fall down.

 

[AnotherDilbert]

Swing wing.

F-14:

94 m² wing area (incl. fuselage) for 34 tonnes, or 5500 m² per Free Trader. No panacea?

 

[mike wightman]

F15 E - 57m² 37 tonnes - and will fly with at least one wing shot off.

 

[AnotherDilbert]

F15 E - 57m² 37 tonnes - and will fly with at least one wing shot off.

So, 3000 m² per Free trader (with both wings).

It will fly with one wing (~1500 m² per FT), but what's the MTOW and take off speed with one wing?

I suspect fly with one wing means stay aloft for a while (partly on drive thrust), then make a controlled crash landing?

Yes, stayed in the air 10 miles requiring afterburner, but no, controlled landing (just about).

 

[AnotherDilbert]

I believe very firmly in the movement system, but the paired combat system does need some tweaking to make it the full on terror it should be.

Closing battles would take longer to prosecute then one shot in most cases when we are talking the average battle space, inside the 100D limit.

The problem is planning ahead to actually achieve your goal, not just accelerate wildly...

I made a spreadsheet to visualise future movement.
Here is a scenario where a ship (red) jumps in ~1 000 000 km from a planet (blue) that is moving at a constant rate, and a second ship (green) moves from the planet to intercept the red ship. Both ships have 4 G.

The ships start at the botton of the graph and moves upwards. The red dots mark turn 8, that is when the green ship has to turn over to accelerate back towards the planet to intercept the red ship.


Round 15 the red ship turns over to decelerate:

Range is below 300 000 km for the first time.


Interception happens around turn 21 20, when the red ship is slightly behind, but with a slightly higher velocity:

So, we have to plan more than 10 turns ahead to make a simple intercept.


At round 30 29 both ships have matched vectors with the planet




The red ship could deny interception by accelerating hard to the left, passing the green ship (and the planet) at high speed.

 

[kilemall]

The hits start landing once below 500000 km, several turns of that. Which will effect intercept either way, the intruder avoids the interceptor by damaging drive/power or the intruder loses accel thus not able to avoid interception and will miss the planet.

Anything and everything ship combat/ops requires planning ahead. Vee is destiny.