Forthcoming B-17 wing AD

[aerovin]

Looks like an AD will be issued on Wednesday, 5/17. This link shows what is coming.

https://public-inspection.federalregister.gov/2023-10624.pdf?fbclid=IwAR0UajFGs1C54k5CkSiSxy_MPKUUo1zrpyNklNxjD8uVAbRd8fKRVTRVUTs

I think Vintage Aviation News was the first to spot it.

https://warbirdsnews.com/

Effective date appears to be 15 days after issuance.

[bdk]

My interpretation: So, perform an inspection unless you have already performed the 2001 AD mandated inspection... Once you perform the 2001 AD inspection you have ten years/2500 flight hours until you need to inspect again.

This AD doesn't appear to be nearly as dire as many predicted, unless of course you have damage like the EAA found. Kudos to them for identifying the failure before a risk to flight safety was realized.

FAA estimates the following costs to comply with this AD:

Inspections* 25 work-hours X $85 per hour = $2,125 $25 $2,150 $38,700
Reporting 1 work-hour X $85 per hour = $85 $0 $85 $1,530
*Estimates are provided for the eddy current bolt hole inspections of the most inboard fastener
only.

(g) Inspection
Before further flight: Perform inspections to detect cracking and corrosion by
doing the actions specified in either paragraph (g)(1) or (2) of this AD. No action is
required by this AD if all wing terminal fittings have been inspected in accordance with
paragraph (b)(1) of AD 2001-22-06, Amendment 39-12485 (66 FR 54111, October 26,
2001), and, as of the effective date of this AD, no more than 10 years or 2,500 flight
hours have accumulated since that inspection.

(1) Separate all 8 wing terminal-to-spar chord joints (wings off) and perform a
magnetic particle inspection of the steel terminal fittings and an eddy current inspection
of the 8 inboard holes in the end of the spar chord, in accordance with procedures
approved by the Manager, West Certification Branch, FAA.
(2) On the left and right lower forward terminal fitting-to-spar chord joint
assemblies, remove the most inboard fastener common to the spar cord and the terminal
fitting, and do an eddy current bolt hole inspection on the steel terminal fittings and on
the aluminum spar chord in accordance with procedures approved by the Manager, West
Certification Branch, FAA.

[lmritger]

I am not a B-17 operator (obviously) but considering the costs and effort involved in keeping such a large and complex aircraft airworthy, this seems like a very reasonable directive... and it's not some snipe hunt, either, it's based on documented evidence.

Question - I've been hearing a lot of murmuring about spars lately, was that due to uncertainty over what was found on Aluminum Overcast, and what the remedy might have required? In other words, do we still need to be concerned about spars being a weak point or possibly subject to a separate AD?

Lynn

[aerovin]

After a close read, I posted a detailed look at what I think the AD entails at aerovintage.com

https://www.aerovintage.com/home/blog/

[TAdan]

Excellent write up Scott. Thanks.

[aerovin]

So it seems the Arizona Base CAF people are unofficially and informally saying that the inner spar tube-to-wing attach fitting inner-most bolt was removed and inspected on Sentimental Journey in accordance with the AD and, once put back together, it will remain airworthy and meet its summer tour schedule. If all that is correct, that is great news.

Removal of that inner bolt is problematic because structure has to removed to provide access. Whatever, the CAF guys figured out how to do it.

So, no cracks or corrosion evidently found on one of the three airworthy B-17s directly covered by the AD.

https://www.facebook.com/groups/9261317727/permalink/10160962380137728/

[bomberfan]

So it seems the Arizona Base CAF people are unofficially and informally saying that the inner spar tube-to-wing attach fitting inner-most bolt was removed and inspected on Sentimental Journey in accordance with the AD and, once put back together, it will remain airworthy and meet its summer tour schedule. If all that is correct, that is great news.

Removal of that inner bolt is problematic because structure has to removed to provide access. Whatever, the CAF guys figured out how to do it.

So, no cracks or corrosion evidently found on one of the three airworthy B-17s directly covered by the AD.

https://www.facebook.com/groups/9261317727/permalink/10160962380137728/

I saw that too, I figured this was going to be a tougher procedure than that. Hopefully the rest have similar luck.

[bdk]

So it seems the Arizona Base CAF people are unofficially and informally saying that the inner spar tube-to-wing attach fitting inner-most bolt was removed and inspected on Sentimental Journey in accordance with the AD and, once put back together, it will remain airworthy and meet its summer tour schedule. If all that is correct, that is great news.

But numerous sources stated that the fleet was grounded indefinitely!

[JohnH]

So it seems the Arizona Base CAF people are unofficially and informally saying that the inner spar tube-to-wing attach fitting inner-most bolt was removed and inspected on Sentimental Journey in accordance with the AD and, once put back together, it will remain airworthy and meet its summer tour schedule. If all that is correct, that is great news.

But numerous sources stated that the fleet was grounded indefinitely!

Must be the same internet experts on Racer that said on Monday, “Graham Rahal will NEVER drive the DRR car this weekend at Indy.”

[Xray]

So it seems the Arizona Base CAF people are unofficially and informally saying that the inner spar tube-to-wing attach fitting inner-most bolt was removed and inspected on Sentimental Journey in accordance with the AD and, once put back together, it will remain airworthy and meet its summer tour schedule. If all that is correct, that is great news.

But numerous sources stated that the fleet was grounded indefinitely!

The fleet of 3 ?
Yankee cancelled the entire 2023 season for their B-17 because of this, easy to crow from hindsight.

[Archer]

UK-based B-17G G-BEDF 'Sally B' is also staying on the ground for now, see here: https://www.sallyb.org.uk/news.htm#grounded23

[bdk]

The fleet of 3 ? Yankee cancelled the entire 2023 season for their B-17 because of this, easy to crow from hindsight.

The FAA is using this AD note to gather more data. The risk is that once the current inspections are done and the aircraft are reassembled, the FAA will revise the AD (or issue a new one) requiring the operator to remove the wing again and do more. For some, just waiting for the final result makes more sense, especially if any ride program does not generate sufficient revenue to give a clear return on investment.

[Xray]

The fleet of 3 ? Yankee cancelled the entire 2023 season for their B-17 because of this, easy to crow from hindsight.

The FAA is using this AD note to gather more data. The risk is that once the current inspections are done and the aircraft are reassembled, the FAA will revise the AD (or issue a new one) requiring the operator to remove the wing again and do more. For some, just waiting for the final result makes more sense, especially if any ride program does not generate sufficient revenue to give a clear return on investment.

Makes sense, so they are grounded ,,, Indefinitely ??

[aerovin]

So it seems the Arizona Base CAF people are unofficially and informally saying that the inner spar tube-to-wing attach fitting inner-most bolt was removed and inspected on Sentimental Journey in accordance with the AD and, once put back together, it will remain airworthy and meet its summer tour schedule. If all that is correct, that is great news.

Removal of that inner bolt is problematic because structure has to removed to provide access. Whatever, the CAF guys figured out how to do it.

So, no cracks or corrosion evidently found on one of the three airworthy B-17s directly covered by the AD.

https://www.facebook.com/groups/9261317727/permalink/10160962380137728/

So, now I have it on good authority that Sentimental Journey is not, in fact, ready to go. The inspection required by the AD is complete but the FAA needs to approve the inspection. The B-17 has come off the first stop of the summer tour (ABQ) and Loveland-Fort Collins is doubtful. Check here for the published AZ CAF schedule. https://www.azcaf.org/tour/

I hope to post more info at my aerovintage.com site later today: https://www.aerovintage.com/

[Matt Gunsch]

So, now I have it on good authority that Sentimental Journey is not, in fact, ready to go. The inspection required by the AD is complete but the FAA needs to approve the inspection. The B-17 has come off the first stop of the summer tour (ABQ) and Loveland-Fort Collins is doubtful. Check here for the published AZ CAF schedule. https://www.azcaf.org/tour/

I hope to post more info at my aerovintage.com site later today: https://www.aerovintage.com/

They do not have to wait for the FAA, once the inspection is done, a logbook entry is made stating that the AD had been complied with and the method, and the report sent to the FAA, all it takes to return it to service is the signature and certificate of the A&P doing the AD.
With the Eddy current inspection once it is done, they will receive a report from the NDT tech, if no flaws are found, per the AD, no further action is required. logbook entries and done.