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The Aphid is a 4-launch, 1-furnace Factorio space ship which uses only Nauvis non-quality tech. EDIT see The Gnat for a faster 4-launch ship.
Shoutout: This ship is inspired by (and steals tech from) the minimalist ship designs of u/TrollDruel.
TL;DR: continuous-duty Nauvis/Fulgora lap time: 1.5 hours
In this route, we stock up on ammo only in Nauvis orbit and avoid loitering at Fulgora.
Youtube test footage of Nauvis/Fulgora laps: https://youtu.be/WcDLn2V3fr8
While a hop to Fulgora and back can be completed in just over 30 minutes, the ammo restock period at Nauvis pushes the total lap time to about 1.5 hours on average.
A route which loiters at Fulgora is not possible with only one furnace, as the resulting rate of ammo production is slightly less than the ammo consumption required to defend against asteroids, even with only a single turret. Very slowly, the ship will starve of ammo and be destroyed.
This ship suffers from some heavy compromises on practicality in order to fit in the "4 launch" category:
- When in hostile orbit, a single furnace barely breaks even with the ammo consumption of defending itself from asteroids. Restocking ammo while in Vulcanus, Fulgora or Gleba orbit is not practical. Accordingly:
- Only star-pattern routes are possible (Nauvis to X to Nauvis).
- The ship cannot loiter in any non-Nauvis orbit.
- The ship must bring enough ammo with it for both legs of a trip.
- Having only a single turret means speed must be kept below roughly 30km/s.
- Unfortunately, the fuel metering control is very imprecise, so the target speed must be set even lower (20km/s).
- Factorio space momentum seems to have an odd quirk, where a small amount of thrust does not appear to result in linear acceleration, but rather, the ship spends a brief amount of time first getting "unstuck", during which velocity is between 0 and 1km/s.
- In order to avoid saturating the thruster with fuel while the ship is parked, fuel production is halted when velocity is zero. The above momentum quirk means that fuel is not being producing during this "unsticking" period. If a thruster only has a small reserve of fuel, the ship can thus get stuck.
- To avoid this, fuel production must continue to run for some time after the ship stops, in order to build up enough reserve in the thruster to get it "unstuck" when the ship resumes travel.
- Because of the above situation, briefly running out of iron ore during transit can cause the ship to get stuck.
- To avoid this, the furnace is disabled while the ship is in transit, which further exacerbates the already long ammo restock period while in Nauvis orbit.
- Asteroid collector storage is not utilized (asteroids are crushed immediately).
However, if we work within the above limitations, the ship does seem to be reliable. But reliable does not equal practical :).
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