On Tue, Jul 18, 2023 at 03:42:02PM +0000, Traveller Mailing List wrote:
>
> ============================================================
>
> Well, what would/could be a procedure for xfer from an air/raft to an orbiting ship?
>
>
> 1) a/r toodles on up to an orbital altitude & then?
>
> Could one conceivably leave the ground here on Earth & eventually get to the moon?
>
> p.s. pre-MT please
>

Sorry about the late reply and, is 20 mCr = 0.02 Cr? I haven't read
the list in a while and this is a situation very similar to one I had
to deal with back in the day so I couldn't resist the reply.

I'll also start by stating the obvious, how you run your Traveller
campaign is up to you.

------------------------------------------------------------

Everyone refs Classic Traveller differently based on their knowledge
of physics and their interpretation of the rules. I think that's the
beauty of CT. But I also think that it's clear that as group, players
and referees don't have the actual contextual knowledge required to
operate within the envelope of physics in Traveller. It's _science_
**fiction**, that's what makes it interesting and fun. Mathematically I'm
saying that there's a surface in the space where the Y-axis measures
_science_ and the X-axis measures _fiction_ and the Z-axis is a
measurement of possibility or risk. One thing that should be said is
that: *It's okay to infer a contextual knowledge in your role playing
characters that your players do not have.* That becomes important in
this discussion.

*Can an Air/Raft reach orbit?* According the rules, yes but the rules
are mute on whether or not the Air/Raft can reach orbital
velocity. They are however clear that an Air/Raft can reach orbital
height above the surface of a world.

*Can an Air/Raft rendezvous with a ship in orbit?* According to
physics, _no if you assume that the ship is moving at orbital
velocity_. But the Air/Raft _can make the rendezvous if we can slow
down the ship to about 100km/h relative to the ground.

### Here's the rub:

*What's the situation going be like when you get to the ship? How
challenging will the circumstances be?* I wouldn't bet on the
survivability of any object more complex than a large rock that's
forced to move at 100km/h relative to the ground, at a height of 160km
above the ground of a size 8 world. I say this because the average
velocity of unpowered objects in this space must be in the 7km/s ~
8km/s range. A chance encounter with a speck of dust at that 7km/s
difference is going to liberate a lot of energy. A starship is probably built
to handle this, an Air/Raft almost certainly isn't.

### Of Note

It's important to note that depending on the world, a starship or
ship's boat at orbital height moving at 100km/h, ground speed 100+km
about the surface of a size 8 world will be **a huge hazard to
navigation** so trying to do this without drawing attention to ones
self may be a formidable challenge depending on the level of
navigational control in the space.

### The character's contextual knowledge:

YMMV but I referee this as follows: Every school child of Int: 4 or
greater that lives on a world with common space travel will understand
all of this implicitly. Anyone with Pilot-0+ or Ship's Boat-0+ will
also understand this. My son understands this from playing *[Kerbel
Space Program and
KSP2](https://en.wikipedia.org/wiki/Kerbal_Space_Program)*. If a
player says his/her character wants to do this, it's between you and
him/her to come to the mutual understanding that the risk of immediate
death from being hit by a stray piece of debris the size of a ball
bearing must be mitigated to attempt the task at all.

Again, and I might not be considering everything here, but I believe
that the risk can be mitigated. In actuality, the atmosphere is your
friend here. If you can arrange for the rendezvous, do it 75km rather
than 100km+. At some level below 100km there's enough atmosphere to
filter out the fast moving stuff that would damage your Air/Raft, your
ship, and you. You're still a hazard to navigation for any craft that
uses the atmosphere to generate lift.

I've actually been in this situation in the 1980s and I didn't handle
it this way because my knowledge and considerations of orbital physics
aren't what they are now. I also didn't know much about entropy and
angular momentum. This lack of knowledge was a factor in the problem
that I had to solve which was: *Can a Psi character who can teleport
regionally, teleport from the surface to his ship in orbit?* Finally,
I'm not saying that I'm a rocket scientist now, just that I was way
less of a rocket scientist in the 1980s. At the end, it doesn't
matter. I used a shallow interpretation of the CT rules and allowed
the rendezvous to happen in orbit.

--
Chris

      __o          "All I was trying to do was get home from work."
    _`\<,_           -Rosa Parks
___(*)/_(*)____.___o____..___..o...________ooO..._____________________
Christopher Sean Hilton                    [chris/at/vindaloo/dot/com]