It appears that AnubisTTP may be right about the lowest ID number.
I had created a plug to make Manta Bays and Mantas available in the Federation to see how they performed. I had used the Manta Nil'kimas as ammo, and discovered that it wouldn't dock.
After reading this, I went and exchanged the Nil'kimas and the standard Manta in the plug, standard Manta ID315 and Nil'kimas ID161, and reset the bay to use 161 as its standard ammo.
Started up, bought a Manta Bay and six Mantas, spaced out and launched my fighters, and then recalled them. They docked immediately without problem.
When I had tried to dock them in the previous setup, they just swung from side to side of my starbridge, but wouldn't dock, even after 11 minutes of swinging by my watch.
Incidentally, while I am nattering, does anybody else feel as I do that the mass of a fighter bay should be set high enough that only large ships willing to convert some cargo space could manage to buy them. When you carry fighters in your ship, you not only have to have space for the fighters, but in reality you would also need extra space for fuel, for maintenance crew, for the fighter pilots, etc. Seems to me that smaller ships should not be able to carry them, only larger ships like carriers.
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