FAA grounds all B-17E,F, & G models

[GeeRam]

Please forgive my ignorance but why is it impossible for them to reproduce the tapered spar tubes?

The tooling no longer exists to do it, so the expense of building new bespoke tooling to draw the tubes with an internal taper, for the small run of tubes needed, is just cost prohibitive. Some of the restoration shops that have worked on B-17's in the USA started looking at this issue several decades ago, and they eventually found that the tooling may have been sold off to China back in the 70's, but the trail basically ran cold after that. Back in the 90's when there were double the number of B-17's still airworthy, it was cost prohibitive to make new tooling, and now with less aircraft, its very much cost prohibitive.

[browningautorifle]

The tooling no longer exists to do it

So after 80 years they well may just become desirable trophies...at least we'll have them to see.

[GeeRam]

Well, two of the B-17's have now been checked as per the FAA directive, and passed clear, and are now back flying again. CAF's Sentimental Journey returned to the air again on the 10th to join Madras, Oregon based Ye Olde Pub, which was passed clear to fly again recently.

[Sapper740]

I was a volunteer at the Vintage Flying Museum in Ft. Worth and helped Chuckie regain her Airworthiness Certificate after the wing spar AD in 2001. We volunteers were very unhappy when a few years later, after Doc Hospers passed away the estate sold Chuckie to the Military Aviation Museum in Virginia Beach.

[Sapper740]

Oregon based Ye Olde Pub, which was passed clear to fly again recently.

Speaking of Ye Olde Pub, Franz Stigler was an associate of mine and a fellow member of the R.C.A.F. Association in Abbottsford, B.C. Canada. Franz and Charlie Brown (Ye Olde Pub pilot) were finally able to meet but Unfortunately I had been deployed overseas. Franz, knowing how much I would have liked to meet Charlie Brown got him to sign a copy of the print, "The Ultimate Honor" by R. Harper who was an Intelligence Officer at the time. Franz signed it too and it now resides in a place of honor in my study.

[Bob Womack]

I was a volunteer at the Vintage Flying Museum in Ft. Worth and helped Chuckie regain her Airworthiness Certificate after the wing spar AD in 2001. We volunteers were very unhappy when a few years later, after Doc Hospers passed away the estate sold Chuckie to the Military Aviation Museum in Virginia Beach.

She was out here a few years and got a ball turret and some restoration and was sold to Erickson Aircraft Collection where she became “Madras Maiden”. Ericson leased her to the Liberty Foundation, had her painted olive drab, removed the chin turret and Cheyenne tail turret position, and renamed her "Ye Old Pub."

Bob

[GeeRam]

Well, the Sally-B team have just confirmed that the inspection on their B-17G has been completed at Duxford, results sent to CAA and FAA, and both have sanctioned her return to the air, and she should be flying again this weekend.
So, that's 3 of them back flying now.

[GeeRam]

Now seen confirmation that the last of the four currently flyable B-17's, Yankee Lady has now also passed inspection as per the new AD, and will be returning the air shortly. So, that's now all 4 back in the air, with none showing signs of the issues as seen on the EAA's Aluminum Overcast back in 2021, which lead to this AD being issued.

[browningautorifle]

Franz Stigler was an associate of mine and a fellow member of the R.C.A.F. Association in Abbottsford

I didn't know he lived in the area... Adolph Galland didn't know about the incident until several decades later during a televised interview when Franz told the story. Galland turned and said "I'd have SHOT you"...

[Bruce_in_Oz]

A tapered spar tube?

There are several ways to produce a tapered tube, on any scale.

If the tube, be it steel or of some interesting aluminum alloy, is ductile enough, it cam be run into a gigantic "sizing" die, or "spun" with traveling dies", squeezing the parallel tube into a "conical" tube. This process will ado elongate the tube, in much the same way the starting blanks for hammer-forged barrels "stretch" as they are hammered.

NOT ALL ALLOYS are equal. Choose wisely and get opinions from several actual metallurgists.

IF the spar is readily removed and replaced, IFF replacements are available, then do it.

Failing that; perpetual hangar queens. Wreckage-strewn craters are a "different" sort of "interesting".