On Thu, Jan 25, 2018 at 01:14:58AM -0500, Caleuche wrote:
> If you then compute where Hot chi will be in 780414 seconds and then
> compute the time of flight from start point to that and continue to
> iterate until you get the flight time with the minimum position
> error you end up with 780366 seconds. I think it's very close to the
> naïve estimate by luck

Not really by luck.  It's the effect of the ship's acceleration being
enormously greater than orbital accelerations.

> The most difficult part though, is that the difference of initial
> velocity of the Hamiltonian with the expected final velocity (that
> of Hot chi in 780366 seconds) is 22730.9 meters/second, requiring an
> additional 38m37s worth of thrust, and somewhat screwing up all
> previous calculations. Obviously this can be ignored for all but the
> most technical of games.

You can still do this in a "turnover" trajectory with the acceleration
in the second half not being precisely opposite the first.  The nice
part is that the obvious midpoint correction is also the best linear
approximation to the true requirement for this type of trajectory, so
the error at the end would be very minor.

> I wonder how many derelict spacecraft there are out there in the
> traveller universe, drive systems failed, drifting at >0.01c, doomed
> to wander the universe with the unfortunate player characters
> forever. It's one way to end a campaign.

It would have to be a pretty well-tuned disaster to knock out all of
the ship's drive systems as well as the drive systems of all carried
subcraft, without destroying the ship entirely.

But yes: given typical Traveller maneuver speeds, if drive systems do
completely fail mid-trip (even on a relatively short boost like planet
to 100D), then the ship isn't going to hang around in orbit of
anything.  It's going to head out in nearly a straight line.

- Tim