Job offer

I recently was offered a verbal job offer on july 1st, which i accepted. I am still waiting for the official job offer through global staffing. I have been in touch with the hiring manager several times but it seems hit or miss....and he is not sure why it is taking so long. Says he will check on it but it is going on 6 weeks now. Is this normal or should I be concerned? I know i have nothing to worry about with my background check other than a bankruptcy. The hiring manager did send it back 4 weeks ago to change the job description some.

Congrads RJ. Any word back yet?

It is not unusual to have to wait 2-4 months for an official job offer to come from Global Staffing after receiving the initial job offer from the hiring manager. It's unfortunate it takes so long, especially if you are unemployed at the moment!
There are a lot of factors going on in the background which you can't see, but don't worry, unless word of a hiring freeze comes down from higher up the food chain, (not likely at any time in the foreseeable future), your paperwork is slowly making it's way across all of the desks of those who have to review and approve hiring decisions.
In the interim, call or send a short, to the point email along the lines of "Hi, I'm just checking in to see if you've heard anything?" to your Boeing contact. If anything goes awry, they are likely to be the first to know. Otherwise, just try to be patient, the offer is coming.