HAWK21M From India, joined Jan 2001, 31201 posts, RR: 58 Posted (1 year 1 month 3 weeks 1 day 7 hours ago) and read 2228 times:
In case there is an unfortunate damage to the RVSM area around the static port area,which is beyond go limits needing a patch repair under the Static port & expanding outwards say approx 3-4 inches,but since the patch in the RVSM zone....What transpires.
Will that Aircraft always be required to fly NON RVSM or how can RVSM status be restored on that Aircraft?.
fr8mech From United States of America, joined Sep 2005, 4245 posts, RR: 12 Reply 1, posted (1 year 1 month 3 weeks 1 day 5 hours ago) and read 2201 times:
The local engineering department, in accordance with manufacturer and regulatory guidance, will make the final determination as to the repair scheme. But, I have seen a small area of damage enlarged so that the repair area grows. It's quite possible and likely that a flush repair be ordered instead of a doubler/tripler as the case may be.
I can't imagine that an operator would even consider remaining non-RVSM for a long period.
737tdi From United States of America, joined Sep 2007, 465 posts, RR: 0 Reply 3, posted (1 year 1 month 3 weeks 10 hours ago) and read 2030 times:
If I recall correctly on the 737, the existing static port would be removed then a repair large enough to regain distance limits around/over the port would be installed, then a new port would be installed and spotfaced to limits. With the SRM changing quite a bit it may have changed since the last time I saw it done.
Thats what I think too....If the patch covers the entire static area requiring to be dent free & reinstallation of the Static port over the patch,it should be ok.
However I've noticed a couple of aircraft flying RVSM & having a patch stretching only 3-4 inches in the RVSM zone.I'll try & get a pic if I come accross the Aircraft in future.
767eng From United Kingdom, joined Oct 2010, 47 posts, RR: 0 Reply 5, posted (1 year 1 month 3 weeks 4 hours ago) and read 1957 times:
I'm not sure, I've seen a couple of aircraft with scab patches encroaching into the RVSM area around the static ports but still flying RVSM with the repair approved and permanent.
We've also replaced and entire skin panel on a 320 because someone hit the RVSM area with a set of steps and dented it badly.
boeing767mech From United States of America, joined Dec 2000, 992 posts, RR: 3 Reply 8, posted (1 year 1 month 2 weeks 6 days 11 hours ago) and read 1790 times:
Quoting fr8mech (Reply 1): I can't imagine that an operator would even consider remaining non-RVSM for a long period.
Depends on the carrier and the aircraft's mission, my little bankrupt carrier has a 757 that has been out of RVSM complience for a couple of years now because of a dent in the RVSM critral inspection area. Since this aircraft is a NON-ETOPS and NON-OVERWATER aircraft and the damage is allowable without a repair. The company doesn't want to spend the money to repair the dent to make the airplane RVSM qual'd
tdscanuck From Canada, joined Jan 2006, 12709 posts, RR: 81 Reply 10, posted (1 year 1 month 2 weeks 5 days 18 hours ago) and read 1681 times:
Quoting HAWK21M (Reply 9): Quoting fr8mech (Reply 7):
If the engineering department says it's ok, then it's ok
shouldn't it be approved by the Manufacturer & regulatory first
In order to be approved by engineering, it has to be approved by the regulator. This doesn't necessarily mean the regulator actually explicitly approved it though...many airlines have their own engineering capability and delegated authority to approve repairs. This is very similar to what the OEM's do...the regulators actually explicitly approve only a vanishingly small number of repairs. The regulators delegate their authority to qualified engineers at the OEM's, and some airlines if they can demonstrate the capability.
HAWK21M From India, joined Jan 2001, 31201 posts, RR: 58 Reply 11, posted (1 year 1 month 2 weeks 5 days 15 hours ago) and read 1661 times:
Quoting tdscanuck (Reply 10): The regulators delegate their authority to qualified engineers at the OEM's, and some airlines if they can demonstrate the capability.
Agreed.....But what explains the variation in the RVSM Area repairs.....Who is wrong.
tdscanuck From Canada, joined Jan 2006, 12709 posts, RR: 81 Reply 12, posted (1 year 1 month 2 weeks 5 days 14 hours ago) and read 1659 times:
Quoting HAWK21M (Reply 11): But what explains the variation in the RVSM Area repairs.....Who is wrong.
Possibly none of them...the ability to approve a repair is directly related to how well you know, exactly, what the actual requirements are and how your repair will impact them. That, in turn, depends on your engineering analysis capability and your access to the original requirements and specifications. The very same repair may be approvable by one organization and not approvable by another because one may have the ability and authority to show compliance and the other may not.
HAWK21M From India, joined Jan 2001, 31201 posts, RR: 58 Reply 13, posted (1 year 1 month 2 weeks 1 day 21 hours ago) and read 1395 times:
Quoting tdscanuck (Reply 12): The very same repair may be approvable by one organization and not approvable by another because one may have the ability and authority to show compliance and the other may not.
Shouldn't an approved organisation for that task have the capability if approved.
tdscanuck From Canada, joined Jan 2006, 12709 posts, RR: 81 Reply 14, posted (1 year 1 month 2 weeks 1 day 13 hours ago) and read 1355 times:
Quoting HAWK21M (Reply 13): Quoting tdscanuck (Reply 12):
The very same repair may be approvable by one organization and not approvable by another because one may have the ability and authority to show compliance and the other may not.
Shouldn't an approved organisation for that task have the capability if approved.
Not really; any organization that's approved to certify their own repairs still needs to complete paperwork so say that they certify that the repair meets the FARs (or whatever the equivalent is in the relevant country). The trick is in being able to prove that you meet the FARs. A complex repair in a tricky area is difficult to analyze; a large MRO or airline with a very capable engineering group might be able to do very detailed analysis to show that the repair is good. A small operator, faced with the same repair, might not have the capability or know-how to show that the repair is good so, even though they're an approved organization, they may not be able to approve that particular repair.
A big kicker with repair design is knowing the loads; usually on the OEM knows that. That leaves 3rd parties with the task of proving that the repair is at least as strong as the original (hence must be strong enough for the loads)...that can be very easy or very difficult to do depending on the complexity of the repair.