Hundreds of F-35s have wrong fasteners

originally posted by: face23785
I guess it's naive of me to wonder how such a simple mistake makes it this far into the process.

Not the exact fasteners, but you get the idea. They don't look that different. The Fort Worth plant had the same problem with the F-16 because they look so similar.

Problem is all aircraft fasteners (should) have head markings to identify what type it is..

a reply to: Bluntone22

That's called a coincidence, or serendipity.

a reply to: manuelram16

Although it's tricky for nonEuropean mechanics, nobody uses the guide bolts, I don't.
Another irony is the bolt vs nut arrangement, I am pretty sure the reason for bolts is corrosion resistance, having the threads buried in hub instead of a nut exposed to the environment... that's just my theory. The reason sure isn't ease of installation!
I think the Lamborghini Ti bolts are around $14 vs $2 for a steel one. I only know this because they fit my Audi, but not my Mercedes. The wheels interchange between brands, but not the bolts.
Don't even get me started on cone seat vs ball seat.

a reply to: Blackfinger

Or a proprietary driver, like Triple square or XZN

Are the F-35 critical fasteners safety wired?

a reply to: mtnshredder
Only on systems I think.Structural fasteners usually have a wax or seal on them to show if they are turning..
For anyone interested in fasteners here is a quick guide..
Aircraft Fastener guide

a reply to: Blackfinger
OK thanks. I know fastener tech has changed over the years, so I wasn't sure how much safety wiring still went into modern day aircraft.

a reply to: mtnshredder
I work on the old stuff so safety wiring is still a thang with me..

a reply to: mtnshredder
Lock wiring/safety wire/safety cable, is used on system components like pumps, motors ,valves, actuators etc as Blackfinger eluded. Some lock wiring has been replaced with systems like safety cable which are quick and easy to install. Split pins are also still used. Structural assemblies by and large dont use such systems as they are designed to not come undone, however they are frequently potted in wet and/or sealed with airframe or tank sealant depending upon location and fastener type. The sealant is designed to limit corrosion and exposure to moisture or salt and corroding compounds. It can also act as a visual indicator when it cracks and twists if you have rotating or migrating fasteners much like torque stripe compound on nuts and bolts does (we call it cocky sh*t in Australia because of its resemblance to cockatoo poo!) Suspect fasteners can sometimes be permitted to remain in place so long as they are inspected on a scheduled basis. The usual step is to paint a net red stripe across the fastener head to either side, that way if it moves further the line will be broken and immediately visible as well as give an accurate measure of how much rotation occurring.

I expect that inspection cards will be drawn up for the F-35 fleet and will be carried out periodically and sample fasteners may be pulled to look for signs of damage, work hardening or corrosion. That way a trend line can be established and a tailored practical permanent solution devised.

originally posted by: Zaphod58

originally posted by: face23785
I guess it's naive of me to wonder how such a simple mistake makes it this far into the process.

Not the exact fasteners, but you get the idea. They don't look that different. The Fort Worth plant had the same problem with the F-16 because they look so similar.

I guess no matter how good your QC is there's no accounting for human error.

a reply to: face23785

The trick is to learn from previous lessons and come up with ways around human error.

a reply to: Zaphod58

Right. That's kinda what I expected should have already been done in this case. Surely this isn't the first time that company installed the wrong part on something. You'd think they'd have procedures in place to prevent that.

In the Air Force, I remember many instances of flight or squadron leadership trying to come up with such procedures in response to a mistake/accident. Sometimes they would go way over the top and do something so ridiculous and time-consuming that no one would follow it. Sometimes they were too worried about showing their superiors that they did something rather than coming up with something effective and sensible.

originally posted by: Blackfinger
Titanium work hardens and also gets harder with heat but yes Inconel is better for Corrosion resistance..Grease pencils and carbon pencils are a big nono with Ti...
If they are HiLoks its going to take some time to replace them..Cherry Maxes,well Id have a good mental support crew for the workers

Taper Loks no dont even ask...

Thanks. Now I'm having flashbacks.

a reply to: JIMC5499

You have a message that will probably give you flashbacks and cringe at the same time.

a reply to: face23785

That happened in the 80s. It turned into a disaster that everyone learned from, until everyone involved retired and it started all over again.

So, this is about 2 year old news. LM made it's own teams as well as putting NG on contract to handle this.

Always more to the story.

a reply to: thebozeian

Thx for the 411, learned a few things in this thread.

a reply to: Checkpointbravo

It is, but there are still a lot of aircraft out there that may need fixing and will need increased inspections.

a reply to: Zaphod58

That's what I mean.

They're literally tearing birds apart, running HFEC through the holes, oversizing if required, and putting new hardware in. There's a huge IMS and it's being done daily at sites all over.