I never heard of the term.. what do you mean Licensed Airworthiness Engineer ? You mean an Airline QA engineer? those are the ones who ensure everything conforms to airworthiness regulations similar to working for the CAA..
or you mean you want to be a Licensed Aircraft Maintenance Engineer ? Those are the ones who do the actual job..
Anyway, the two starts with the same route, but QA usually requires more exeperience.. so Basically you need an EASA 66 license.. there are many threads here on how to get one..
The pilot exams doesn't help in engineering careers to my knowledge unless you get a job at Safety.. when the two combined might make your CV look good..
I hope that helps.. and you may wanna clarify more on what you do and what exactly do you want if you want further help..
regards,