How to calculate dTons of a ship?

[Disco Soup]

So I'm working on a ship concept, and I've got its physical dimensions down, but I want to know how many tons to give it for creating it stats. It's a rocket with a diameter of 28 meters and a length of 78 meters. The engine takes up the back 33.5 meters, which leaves the 44.5 meters for the mission module. That module has an internal volume of 11,325 meters. Can anyone tell me how I should calculate the dTons of this baby?

 

[whulorigan]

So I'm working on a ship concept, and I've got its physical dimensions down, but I want to know how many tons to give it for creating it stats. It's a rocket with a diameter of 28 meters and a length of 78 meters. The engine takes up the back 33.5 meters, which leaves the 44.5 meters for the mission module. That module has an internal volume of 11,325 meters. Can anyone tell me how I should calculate the dTons of this baby?

V_Cyl = πr²L

V_Cyl = Volume of Cylinder (in m³)
r = Radius of cylinder (in meters)
L = Length of Cylinder (in meters)
​

1.0 dton = 14.0 m³

 

[Disco Soup]

TYVM. I am familiar with the formula for the volume of a cylinder, but that should also help anyone else who searches this.

Looks like when you account for the cone and the empty space in the engine section we're looking at a 1445 dton ship.

 

[atpollard]

... a rocket with a diameter of 28 meters and a length of 78 meters. The engine takes up the back 33.5 meters, which leaves the 44.5 meters for the mission module. That module has an internal volume of 11,325 meters. Can anyone tell me how I should calculate the dTons of this baby?

V_Cyl = πr²L

V_Cyl = Volume of Cylinder (in m³)
r = radius of cylinder (in meters)
L = Length of Cylinder (in meters)
​

1.0 dton = 14.0 m³

Looks like when you account for the cone and the empty space in the engine section we're looking at a 1445 dton ship.

I come up with different numbers for the answer ...

R = 28/2 = 14 m
L = 33.5 + 44.5 = 78 m

Whole ship:
14m x 14m x 3.14 x 78m = 48,004 cubic meters.
48,004 cu.m. / 14 = 3429 dTons

Engines Only:
14m x 14m x 3.14 x 33.5m = 20,617 cubic meters.
20,617 cu.m. / 14 = 1473 dTons

Mission Module:
14m x 14m x 3.14 x 44.5m = 27,387 cubic meters.
27,387 cu.m. / 14 = 1956 dTons

[Somebody might want to check MY arithmetic.]

 

[pendragonman]

Other that pi is not 3.14...but I guess that is close enough for an engineer.

 

[whulorigan]

I come up with different numbers for the answer ...

R = 28/2 = 14 m
L = 33.5 + 44.5 = 78 m

Whole ship:
14m x 14m x 3.14 x 78m = 48,004 cubic meters.
48,004 cu.m. / 14 = 3429 dTons

Engines Only:
14m x 14m x 3.14 x 33.5m = 20,617 cubic meters.
20,617 cu.m. / 14 = 1473 dTons

Mission Module:
14m x 14m x 3.14 x 44.5m = 27,387 cubic meters.
27,387 cu.m. / 14 = 1956 dTons

[Somebody might want to check MY arithmetic.]

Your math looks good, atpollard.

 

[WistfulD]

Other that pi is not 3.14...but I guess that is close enough for an engineer.

You are already limited to 2 s.d. with 1 dTon=14 m^3. Refining the accuraccy of pi will not increase the accuraccy of your calculation.

 

[atpollard]

Other that pi is not 3.14...but I guess that is close enough for an engineer.

Your math looks good, atpollard.

You are already limited to 2 s.d. with 1 dTon=14 m^3. Refining the accuraccy of pi will not increase the accuraccy of your calculation.

:rofl:
I love this place. Where else can you have conversations like this.

Disco Soup:
Since I hate to stress over the decimal points and I am usually satisfied with single digit precision, I would call it a 3500 dTon ship with a 2000 dT Mission Module.

 

[Disco Soup]

Yes, but the engine section is really not as bit as it seems. This thing is basically a barbell with one side shaped like a bullet head.

 

[elbmc1969]

Yes, but the engine section is really not as bit as it seems. This thing is basically a barbell with one side shaped like a bullet head.

Could you give the actual dimensions of the sections, then?

Is there a reason for the "shaft" of the barbell, other than the rule of cool?

 

[pendragonman]

Could you give the actual dimensions of the sections, then?

Is there a reason for the "shaft" of the barbell, other than the rule of cool?

Saves mass. Actually makes the dtons smaller as well, since the narrowed neck was not considered.

 

[Disco Soup]

Yeah, I can't actually determine the exact dimensions of the shafts (there are several, they serve as shock absorbers), so I made a guesstimate and used that. This is based on old tech and uses a fission reactor. The engine is way bigger than Traveller rules call for, so I just noted that the engine section is also fuel storage and called it good.

 

[Disco Soup]

And part of my problem is that I just looked at the plans again. The original has the mission module with a diameter 2 meters thinner than the pusher plate. It's actually 24 meters wide.

 

[Disco Soup]

The original plans say that the there's 11,326 cubic meters in the mission module, but running it at a radius of 12 meters and a length of 44.5 meters, I'm getting 20121 cubic meters. Shaving off 25 percent for the cone still gives me 15,090, which translates to 1077 dtons.

The main engine section past the pusher plate is also 24 meters, so I've got to recalculate that, too. No big.