Until further notice https://www.airforcetimes.com/news/...g-fortress-planes-grounded-over-safety-issue/
It is an AD, that (minimally) requires pulling a few bolts and doing NDI. Unless you've already done that in the last X years. Doing the inspection probably isn't a big deal relative to the scope of B-17 ownership. The challenge is when/if you find a problem.
Hate to say it, but given recent crash history and use of this platform for large groups of paying riders, not surprising that the FAA has a lower tolerance for risk. Another Nine-O-Nine would probably end the "ride a WWII bomber" thing for good.
Being as there are only two flying B-17's in the US and one in Europe that are not already undergoing wing pulls for this AD, you can probably expect them to do the wing pull also. All the other potential flyers around the world, are undergoing heavy maintenance or restoration and have their wings off, so the fittings will be pulled and inspected. The big problem is the wing spar chord members are unobtainium, and all the usable ones are already in flyers. I suspect the B-17 consortium is already working on the process to make new spar chords, or engineer a better replacement.
This. The wing spar is a truss. The upper and lower members are internally tapered rectangular tube extrusions. Nobody has the tooling to make them today. Gonna be very spendy to make new ones. And installing new ones will be a huge undertaking.
I suspect that what is going to be done, is go with a constant section tube, with enough milling to fit the attach fittings. At 25 feet in length, about the only way you can easily taper the inner profile, is using a custom extrusion press and a set of closed dies. You are probably talking well into 7 figures to create the dies and the press. Going with a constant profile is way less expensive, but at the cost of a slight increase in weight. The weight increase isn't really a factor, as all of the a/c are operated well below combat weights. I'd be willing to be Ray Moore is deeply involved in the project, as he's already built a number of both fuselage and bomb bay trusses for various B-17 restorations as well has his new construction one.
I saw the AD specifics elsewhere. I'm no A&P, but it did stick with me that the estimated inspection costs are ~$38K at $85 hourly, and the AD made a note that it is very difficult to estimate this since there are so few examples. It's wonderful to see these fly, and there is so much time, effort, energy, and money behind the scenes to make that happen.
