I'm having trouble unlocking Sector 8, and have been for almost two weeks now. We've unlocked sectors 1-7 and 11, Our airship is rank 27, and we're using two Invincible parts(Propellers and Aftcastle) and two Enterprise parts(Hull and Forecastle). I've been alternating voyages between just sector 7 or a full trip of sectors 7-5-6-3, when I know I won't be able to attend to the airship for a span of time.

Is something going wrong? I feel our airship has adequate stats, and from what I understand sector 8 is discovered via sector 7, so I've been hitting that hard as I can. If we don't discover sector 8 in a few more voyages, we'll either have to say "screw it" to the second airship gained there, or miss out on going to sector 11 and beyond until the RNG is kind enough to us to give us access to sectors 8-10. Any advice would be appreciated.