Icarus Simulations were once one of the biggest names in the X-Plane scene, but since November 2017, the team has been split and it's payware DC-9 project seemingly abandoned due to inner turmoil at the Greek development group.
The split was announced via the group's Facebook page and split the company in two, with Skyline Simulations handling further scenery projects and Ilias Tselios handling aircraft development under the name ITX-Designs.
In late December last year, Tselios released a blog post with his side of events and reassurance that the DC-9 is on track, although progress is slow.
He writes about the whole Icarus story, from the announcement of the DC-9 in July 2013 until now and provides a rough roadmap for future developments on the aircraft. Tselios speaks of the DC-9 being on the back burner compared to the company's various scenery projects through the years and ultimately lead to some degree of neglect.
Since the blog post, the X-Plane.org forums thread has seen a resurgence with various development updates posted every few days - with the largest recent one explaining the weight and balance menus (the images had previously been posted in October, however a description of the systems was omitted until now)
In regards to navigational capabilities, the developer makes it clear the original aircraft was limited to VOR-to-VOR navigation and will not be integrated with the CIVA plugin as a result. Both the GNS430 and X-Plane FMC will be optional additions though.
Tselios notes that not many WIP previews are available due to the nature of the stage of development they're in, coding the avionics. Here are some early renders of the aircraft, published in 2013:
Many thanks to TestFlight357 for the tip on our Discord server.