someone who actually has experience flying the real thing may have access to certain handbooks, data etc - so there /might/ at least be something to bring to the table to get this bootstrapped - like Thorsten said, at this point it's more about offering something so that others get interested in joining the "effort", even if just temporarily.
In general, it may help to split the effort into little tasks and see if someone shows up to help with something.
For starters, that may involve gathering technical data, 3-views, suitable artwork (licensing!) etc - and maybe starting a wiki article/forum topic to coordinate everything.
More often than not, this is more about being able to compromise than actually getting something done - for instance, 99% of the projects actually fail sooner or later because people are not willing to make concessions, or they don't see the potential of getting involved in other projects before starting their own.
Which is to say, that at this point, it may not be such a bad idea to look at other helicopter related projects and see who's been involved in any of those, and maybe get in touch with the corresponding folks to see if they're currently around or if they need a helping hand with something - for instance, even just providing feedback regarding the handling may suffice to get people interested in looking at your ideas.
Thus, my suggestion would be to do a little research first, look at similar efforts, and determine not just what you need, but also what you yourself can bring to the table to get other people interested in helping with some of this. Some of the most accomplished projects are literally projects that were started years ago, so there's that. Look at any of the helicopters that were created by HHS to see for yourself just much work this is.
That is one of the reasons why many aircraft we have today in FlightGear started out as "compromises" - for instance, by not having a proper FDM, or by having no 3D model - some did not even have a cockpit, others only had a 2D panel - and yet others had a highly realistic flight dynamics model (fdm), but no artwork at all.
As you can probably tell by now, "finishing" an aircraft in the sense of creating something that actually flies somewhat plausibly, is a rather tedious process and it has much more to do with being able, and willing, to make concessions and find compromises to find a working model that gets people motivated to collaborate with you.
And in the light of this being a volunteer-driven project run by people in their own spare time, the whole experience must be "fun", too.
Besides, don't just look at "helicopters" - look at the c172p or even the shuttle, and you will see for yourself, that "creating" an aircraft has more to do with collaborating with others, than doing immediately what you are interested in working on.
That is the primary reason why many interesting projects and ideas fail, usually because people hugely underestimate how much of an impact it has if you show a willingness to get involved in other (more or less related) efforts - which kinda is a "currency" around here, because people may feel that they'd like to help you to return a favor.
Then again, someone who has actual RL flying experience does have something to bring to the table, and depending on the team of volunteers you are able to gather around you, that may even suffice - for instance, HHS is highly interested in realism - and others are highly interested in FDM aspects of helicopters.
Anyway, don't assume for a single second that you'll have a flying Bell47 ready in a few weeks time - it is more likely to take many months, if not even years, to come up with something plausible that will impress a pilot who's actually rated on the real thing.
And like others said already, it does help if you are willing to learn new things and get involved in other projects - even if that only means taking screenshots of helicopters and ree-doing splash screens or other stuff like that with a low barrier to entry (think updating the wiki/docs, adding ratings, translations, contributing to the newsletter etc).
But if you should still have access to the real aircraft, I'd personally suggest trying to bootstrap the whole effort by taking close-ups of the aircraft and sharing this artwork here, so that others can get started with 3D modeling/texturing a simple 3d model for starters, possibly using the flight dynamics of another helicopter for now.
This kind of effort literally is a multi-year jigsaw puzzle, and it has more to do with herding cats and your social skills than anything else - unless of course, you happen to possess many relevant skills, such as holding computer science degrees, or a degree in maths/physics (for the FDM) and 5+ years doing 3D/texturing work