How can a part be milled to a smaller diameter and retain its original strength?
Why wasn't this heavy part made smaller and lighter to begin with?
Can you really determine if it's "crack-free"?
I'd rather have Superior give me a new crank.
Just sayin'.
I don't know 'bout you, but I'm at a loss on how this AMOC is a rational alternative. I have very little engineering background, but...
How can a part be milled to a smaller diameter and retain its original strength?
Why wasn't this heavy part made smaller and lighter to begin with?
Can you really determine if it's "crack-free"?
I'd rather have Superior give me a new crank.
Just sayin'.
Sounds like a plan! Will do!Glad to hear that Martin! Now I am positive you can make Osh-22. Reserve me a parking spot next to you in Sea of RVs I will be a bit late
1. Cranks can be ground undersize in different journal diameters for overhaul. The smallest diameter permissible is the strength limit.
2. So you can overhaul them in the future.
3. Yes, by several means of inspection.
4. Good luck with that.
any updates? I'm one of the lucky ones.
I'd really love to have a sit-down, off-line, discussion with an expert about the Baker-Risk reports and how this AMOC would solve the problems brought up there.
I've received no further news since my last post. I'm assuming that the AMOC has been submitted by now; they expected to submit it very soon after my last post.
Hello , that was we found .we opened it to change the crank shaft . the engine have only 140 hours. i really appreciatte your comments .
You're going to have to replace all of the bearings anyway with a replacement crankshaft. I wouldn't worry about it.
True, but you don't expect to see bearings wiped on a fresh engine. Something wasn't right.
I've already installed a replacement Lycoming crank and now that I understand Superior's plans for the proposed AMOC, I agree with the view across the pond that a reground crank would always be suspect. I don't know what if any financial relief I'll get from Superior, but for me peace of mind is worth the expense.For those of you with an affected crank, who is planning to go with the regrind option, and who is intending to fit a replacement?
For those of you with an affected crank, who is planning to go with the regrind option, and who is intending to fit a replacement?
Here in the UK there are six RV's (and a Fokker Triplane replica) that have Superior cranks in the affected serial number range. The general feeling is that a reground, reinstalled crankshaft will always carry a stigma that "it's one of those bad cranks." Come resale time, any prospective buyer that's diligent is will identify this, and they'd be crazy not to be deducting a chunk of value from the aeroplane to re-assure their purchase. That's if they don't just shake their head and walk away.
After how Superior handled their XP400/XP382 problem with the whole engine buy-back program, is it unreasonable to expect that affected owners are offered a buy-back option on the crankshafts that we do not wish to re-install?
After all, if Superior are confident in their AMOC, then surely their lawyers wouldn't have any issue in having a bunch of reground cranks with paperwork, returned to inventory that they can repurpose/resell?
Unfortunately I also have a crankshaft in the affected range but don’t share the same opinion as others. I think a crank like mine with 500 hours of trouble free operation that is inspected and repaired is likely more reliable not less reliable than a brand new crankshaft. I imagine new crankshafts are subject to the bathtub curve that many products experience, some fail early but those that don’t fail usually live a long life.
Just had the pleasure of talking to Justin Carter FAA engineering who would be one of the folks issuing the AMOC
He stated the AMOC request does not come directly to him first it goes to the district office for initial review.
FAA said:(i) Alternative Methods of Compliance (AMOCs)
(1) The Manager, Fort Worth ACO Branch, FAA, has the authority to approve AMOCs for this AD…
(j) Related Information
For more information about this AD, contact Justin Carter, Aviation Safety Engineer, Fort Worth ACO Branch, FAA, 10101 Hillwood Parkway, Fort Worth, TX 76177; phone: (817) 222-5146; fax: (817) 222-5245; email: [email protected].
I started looking for a replacement to buy since a rebuilt crank in a motor with less than 4 hrs makes no sense to me. I just hope Superior will eventually come to their senses and give their customers the support we're due.