Only Coanda-1910 "unsuccessful" in the entire Timeline of aircraft engine development. Quite strange! 

I have noticed that the entire timeline of aircraft development, ranging from 1848 to 2004, has a single engine labeled as "unsuccessful". All other motors are considered successful also many o them are in the same situation as Coanda-1910. More, some engines never left the drawing board being years later developed by other inventors in efficient motors, with major modifications.

I will delete the epithet "unsuccessful" because I consider it was not placed in good faith. Coanda-1910 power plant itself was built, worked and it was an original design.