Confused about Eligible Additional Classes

[skeolan (OP)]

On the DAC/Rank/Information tab of the f5 Class Design window, there's a list field titled:

Eligible additional classes if this is primary class for a shipyard

This is empty for all of my ship designs but seems like it ought to contain other sufficiently similar ship designs.  Is this a list that gets populated automatically within a certan tolerance, or is there something I have to do manually?

For example, my Geosurvey and Gravsurvey ship designs are exactly equal in tonnage and carry identical components except as follows:

Code: [Select]

Geosurvey: 3x Ion Engine + 3x Geological Survey Sensors
Gravsurvey:4x Ion Engine + 2x Gravitational Survey Sensors
. . .  and these engines and sensors all have the same tonnage and crew requirements.  Seems pretty interchangeable to me! But neither ship is listed as an alternate build option for the other.  Is there a way for me to make that happen?

[Hawkeye]

Any class, that has a maximum refit const of, I belive, 20%, can be build by the same shipyard without retooling.
It is not about mass, but about cost (upgrading armor is a huge factor for refitting, for example)


Edit: Those kind of questions are better asked in the Academy

[Brian Neumann]

Hawkeye is correct.  A good example is to design a standard freighter, then use the copy design button and replace the cargo holds with twice as many cryogenic compartments.  This will give you two ships the same size.  Normally the colony design will show the freighter as a possible ship to build in the shipyard.  The cargo ship however will not show the colony ship as a possible design as it is considerably more expensive.

Brian