A few months ago, there was a thread where we discussed what is the function of those two tubes on the underside of the YF-19's chest.
Some people thought they are chest guns, while others (me) thought they might be part of the transformation mechanism to lock the mecha together in fighter mode. In the end, there was no evidence either way to reach a firm conclusion.
I personally dispute the chest gun theory, namely because no chest guns are mentioned on the Macross Compendium, which is the most accurate and official English language source of information on the YF-19 and a direct translation of Japanese source material.
I couldn't find the old thread, so thought I'd start a new one as I possibly have some new information.
Yesterday, after a couple of years of procrasinating, I finally broke down and purchased the Hasegawa YF-19 model. On the instruction manual, I was surprised to find what appears to be some lineart of the underside of the YF-19's chest area , which looks to be drawn by Kawamori and has some writting perhaps explaining what the chest tubes are. See pic below.
Perhaps Renato would be good enough to translate, so we can end this mystery once and for all.
Graham