From whence I came.

Great observations...thanks!

Little has changed except we got all fancy with acronyms...our bombs hang on TERs...Triple Ejector Racks. A rack is a rack. Check out the rack on my sexy girlfriend...
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Speaking of load bearing on wings. I always regarded those F-16 outboard racks on 3 and 7 to be things of wonder. Without a TER they could hold a single 2000 pound bomb. The load on the wing there is just enourmous. When we let a 2000 pounder drop off, the whole wing would flick up elastically and jolt the entire plane like a rag doll. You could watch the wing spring up and down for a couple seconds afterward. The first time I let one go I about crapped my pants as I thought the wing was going to break off. Later, it was just cool. Always admired you guys who made these things work like they do. Thanks!

 

Bob, keep on "struttin' your stuff". You are awesome.

 

A far cry from the original concept of the F-16 as a simple, air-to-air fighter, rather like a latter-day F-86 Sabre. Could you imagine hanging all that stuff on a Sabre?

I think the silly "F/A-18" designation should be changed back to simply F-18, as it started out to be. After all, from the F-100 onward, just about every "fighter" aircraft ever since has really been an "F/A". (The F-102 and F-106 are the only exceptions I can think of.) Considering its dual-purpose development, I'm surprised (and happy) that the Lightning II has not been renamed "F/A-35".....at least, not yet, and I hope that it never is.

 

Except it is the JSF...Joint Strike Fighter. And the Brits call it the JCA...Joint Combat Aircraft. So nothing means anything anymore. The A-10 can do Air-to-air. They all do it all.

 

A-10?

Just fill the sky with depleted uranium...

 

A rack is a rack unless it is a BRU-3 (bomb release unit) that is still a rack or a LAU-88 (launcher assembly unit) that is a rack with a rail, or a MAU-12 (medium assembly unit), which is still a rack, but has 14" and 30" suspension lugs for lots of stuff. Now racks are often mounted on pylons on fighters, which are really struts with a streamlined cover. Only reason I mention this is that I have dropped/launched hundreds of weapons off our pivot pylons (pivoting struts with streamlined covers) using all of the racks above. Not to mention SUU-20s and 21s (suspension unit universal) which were practice bomb dispensers or mini-racks. The SUU-21 even had bay doors, necessary for overflight in the UK and Europe.

When we carried GBU-15s, we carried a MK-84 on the opposite wing to prevent the leans, same with a GBU-28 (4700 lbs). When we salvoed MK-84s (2000 lbs), only rarely, usually rippled them in singles or pairs, the aircraft leaped upwards, as did the wings. To be expected with an 8000 lb reduction in weight.

 

Cool!

 

Please explain the structural geometry and load paths of this 'strut'.

If I Google 'weapon strut' I get nothing. If I Google 'weapon pylon' there are numerous links.

Apparently the Marines are buying pylons for their F-35's.
https://news.usni.org/2015/08/13/davis-f-35b-external-weapons-give-marines-4th-5th-generation-capabilities-in-one-plane

 

Interesting observation..... One of the causes of fatigue in C-130 wing boxes was apparently from airdropping heavy loads. The load would go out the back and the fuselage would spring up and all the flexing was bad for the wing boxes. The situation was highlighted for everyone with the attention grabbing video where one had the wings fall off in flight:

https://www.youtube.com/watch?v=-A4QZAxrb28

Now I assume the F-16 is built to withstand heavier G loadings and the wing flex may not be such a concern but it's interesting to read similar type observations across very different platforms.

 

That video is real? It looks like a model when the wings are coming off.

 

Jim- We called them pylons, too. You are not likely to get too many engineering hits on the internet about the engineering of them, though.

 

Seriously? Doesn't look at all like a model.

I remember reading about it, happened in CA.

More recently the same thing happened to a PB4Y Privateer (similar to a B-24) firedropping here in CO, near Estes Park (lost one wing).

 

Yep, very real. It was a huge attention grabber for the C-130 community. There was another similar incident in Europe as well.

For a while about 8-10 years ago there were a bunch of C-130s that were speed limited at low altitude due to wingbox cracks. Nothing focuses the mind quite like the thought that the yolk might be unexpectedly yanked with crushing force into your lap momentarily as the wings depart the aircraft only to have the pressure released as the aircraft plummets to ground with mere seconds to recognize that the situation is futile.....😄 I have moved on to more modern aircraft where I fly an even more insane mission, but the wing box stress is fairly low so at least I don't have that to worry about. You will know if it doesn't work out someday as my wife will post something from my account in the subscribed section I suspect.

 

What do egg yolks have to do with it?????

 

You got to love the ERMA's (Easily Recognizable Military Abbreviations)

 

You are a bad bad man! Keep us safe in the world.

 

That airplane was a C-130A, which had a less-robust wing design, without a separate center-section, than the B-model and all later Herks. A beef-up within the wing carry-through structure hid metal fatigue that eventually led to the loss of the wings. That cannot happen on a B or later model C-130, and there are B models from as long ago as 1960 that are still providing reliable service around the world.

 

There were still wing box issues with E & H models and for a while there were a bunch of tails with speed, weight and maneuvering restrictions due to wing box cracks and cracked fasteners. I have one of the cracked fasteners on my desk at work from when they had to inspect the whole fleet back around '08 or so. They may not be as succeptable to the same failure mode as the A models but they are still subject to similar stress and eventually wear out.

 

Which is why we're still building center-wing replacement kits....