Roseflyer From United States of America, joined Feb 2004, 10902 posts, RR: 52
Reply 2, posted (3 years 2 months 3 days 7 hours ago) and read 6915 times:
There is a process usually referred to as PMI. This is where airlines get parts from a supplier that was not the original supplier by Boeing or Airbus. There is a certification process for these parts. Using parts from alternate suppliers are not bogus parts. For example, airlines rarely use the original filter suppliers. They use alternate suppliers who still comply with FAA requirements.
If you have never designed an airplane part before, let the real designers do the work!
KELPkid From United States of America, joined Nov 2005, 6818 posts, RR: 3
Reply 3, posted (3 years 2 months 3 days 6 hours ago) and read 6895 times:
You still have the nutjobs around in GA circles who do things like stick a rebuilt Ford Mustang alternator from the nearest cheap auto parts store in a Cessna 172 when the alternator goes bad, rather than pay the mechanic to put the (PMA'ed version of) the same part in the plane. How these planes ever pass their annual, I'll never know...
Not exactly bogus parts, just unapproved ones (which renders the aircraft unairworthy! ) Not to mention people who overstep the boundary of mechanic and allowed owner maintenance...
Celebrating the birth of KELPkidJR on August 5, 2009 :-)
BE77 From Canada, joined Nov 2007, 455 posts, RR: 0
Reply 5, posted (3 years 2 months 2 days 19 hours ago) and read 6765 times:
Quoting KELPkid (Reply 3): How these planes ever pass their annual, I'll never know...
Quoting amccann (Reply 4): "The Fastener Quality Act" was passed in 1990
Easiest part would have been to pass the annual - they used to look 'exactly' the same as the original part (which is not a suprise, since it was the same, just bought at a different store). You would have had to really be looking for it to find it.
They used the same alternator on Ford tractors for a long time too - and those were even cheaper to buy way back when than buying the same alternator at the Ford auto dealer. Even if you're mechanic noticed it, he'd probably 'not notice' during the annual, since it was the same alternator and it didn't affect the airworthiness - remember too that the manufacturing QA/QC and supply chain processes for parts like this were essentially the same (basically non-existent) for Tractor/Car/Aircraft until conterfeit parts started becoming an issue - as amccam noted things didn't start to change until the 80's and 90's.
Not to say any of this was legal, but things were (really) different then (seatbelts in cars weren't mandatory, no baby seats, and light aircraft (and pickup trucks) had fewer and simpler systems that any backyard mechanic could generally understand and fix. I couldn't change the snake belt on my truck now, but in high school we'd stock fan belts and us kids would install them in 5 minutes at the fuel island as part of normal the service provided at the local 'full service gasoline station".
I do miss the $200 annual (same plane, and I am lucky to get out at $3000 doing all the legally allowed owner assistance tasks - of course is was new in the 80's too and now has 30+ years on it).
twincommander From United States of America, joined Apr 2005, 192 posts, RR: 1
Reply 7, posted (3 years 1 month 4 weeks 4 hours ago) and read 6220 times:
I changed a standby alternator on a caravan a while back... the one i removed had motorcraft stamped on it and the one installed had motorcraft stamped on it. the STC showed that exact ford part number. we paid $450 for the rebuilt replacement from someplace in anchorage, and napa had the same one for $56.40 before core.
however, while napa's would work fine, it would be considered a bogus part, as it is not certified for aircraft use.
aklrno From United States of America, joined Dec 2010, 1217 posts, RR: 0
Reply 8, posted (3 years 1 month 4 weeks 1 hour ago) and read 6185 times:
On a remotely related topic a large number of the parts on a Ferrari are from ordinary parts suppliers who put their ordinary part in a Ferrari box. The price is then multiplied by 10. A $3.50 Fiat oil filter is thus transformed into a $35 Ferrari oil filter. I cannot tell the difference, and I suspect my engine can't either. I once needed a servo motor that Ferrari wanted to sell me for $650. I found the VW version for $50. Worked just fine.
I realize that the difference is that if my car stops I am really just inconvenienced, and if a 747 stops several hundred people are dead, but I can understand the frustration in the budget limited Cessna owner. Still, I wouldn't want to fly in his plane, or be standing under it.
Very true. Also generally not safe, and may be really stupid to use.
There are some pretty unreliable approved parts too that we keep using because the certification isn't worth anyone's trouble.
A couple years ago I got caught in a electrical switch AD, and the $1100 replacement set which will eventually fail the same way could have been replaced with much better stuff for about $50, but it would have cost way more to certify than the $1000 cost per flying mid 70's to mid 80's Beech to certify.
Very true - and the supply chains are managed now to meet those rules, very aggressively.
25 or so years ago, not so much. It WAS the same part, and was tracked equally poorly. Even buying from an av supplier was not a guarentee of anything.
The paper trail, while expensive, has improved enough that it is getting much more difficult to get bogus parts in - and very few accidents are traced back to bogus parts.
(I suppose unapproved is the Ford alternator - maybe it's not bogus because it is the same part number, but it is unapproved since the paper trail back to Ford doesn;t exist, and so it might be bogus...)