Proponents are on both sides when it comes to deciding whether or not the Coanda-1910 was the first modern jet. Based on the wikipedia information, I learned that the Coanda-1910 was the first modern jet, yet unofficially. Its engine did combust in the air and propelled the aircraft, but other say otherwise. It did have an experimental aircraft engine, and it did work to a certain extent.
No, I do not think that the Coanda-1910 can be considered a precursor to the modern jet, because Conada had lots of stories about what the Coanda led to, but the stories were not true. In fact, there was not evidence that the airplane ever even flew. Coanda simply liked to boast, but really, his prototypes did not lead to the modern jet.
I do not think it was the precursor to the jet because it was only a prototype. While it was built, it was never fully developed and if it did have any potential it was never realized. The only way something could be the first of something is if it actually did that something.
A jet is a ducted fan with the energy to drive the fan derived from the combustion of a fuel air mix pressurized by the action of the compressor in the front and with the combustion exhausting through a nozzle in the rear providing the some or all of the forward thrust as well as the energy to drive the compression stages. Although Coanda claimed that he worked with this prior to the appearance of other jet engines, his claims could not be verified.
No, the invention of the Coanda-1910 does not justify his recognition as
father of the jet. There is sufficient controversy, to this very day,
surrounding the claims made by Henri Coanda. A number of aviation
experts and historians argue that the Coanda-1910 failed to actually
fly. Certainly, the work of Henri Coanda lead to the successful creation
of jet power but not until other notable individuals refined and the
developed the technology.