Created attachment 523900 [details, diff]
Enable flite text to speech output.
Flightgear is currently not able to output speech.
The old festival system is not supported any longer (due to the data having been removed), so flite + htsengine are our only options.
This naturally needs app-accessibility/htsengine to be packaged first/added to the tree.
This patch was easily ported to flightgear-2018.3.2, and after defining htsengine, I was able to get TTS in my game. Thanks!