Can someone verify if this is fact or fiction?

That would be a rough fifteen seconds for the two guys in the plane.
 
Saving those who are interested the effort to find the NTSB report:

THE PLT WAS EXECUTING A HIGH SPEED PASS OVER THE RWY AT ABOUT 250 FT AGL. THE PLT THEN BEGAN A RAPID PULL-UP & BOTH WINGS SEPARATED JUST OUTBOARD OF THE ENG NACELLES. RECONSTRUCTION OF THE SEQUENCE FROM A VIDEOTAPE REVEALED THAT THE ACFT'S SPEED AT THE TIME OF THE WING SEPARATIONS WAS 220 KTS. VNE FOR THE ACFT IS 193 KTS. IT WAS CALCULATED THAT, AT 220 KTS & AN 8 DEG NOSE-UP PITCH, THE 'G' LOAD AT THE TIME OF THE WING SEPARATIONS WOULD HAVE BEEN 8.3 G'S.

The National Transportation Safety Board determines the probable cause(s) of this accident as follows:

IN-FLIGHT PLANNING/DECISION..IMPROPER..PILOT IN COMMAND
OVERCONFIDENCE IN AIRCRAFT'S ABILITY..PILOT IN COMMAND
AIRSPEED..EXCEEDED..PILOT IN COMMAND
WING..OVERLOAD
DESIGN STRESS LIMITS OF AIRCRAFT..EXCEEDED..PILOT IN COMMAND

Contributing Factors:
WING..FAILURE,TOTAL
WING..SEPARATION
 
EchoKilo said:
I've always heard from various people over the years that the specs of an airplane as listed in the manual are actually half of what the plane will actually do. So take for example that the Cessna 150 has a useful load of roughly 475 lbs., does that mean 475 is actually half of what it will hold? Just curious. Thanks.
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Let's just cut to the chase: whatever you're thinking about doing, don't.
 
dmspilot said:
DESIGN STRESS LIMITS OF AIRCRAFT..EXCEEDED..PILOT IN COMMAND
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I suspect that it wasn't this one pass that did it. The wings probably had been repeatedly overstressed by the pilot with similar maneuvers until "she couldn't take any more, Captain."
 
flyingron said:
I suspect that it wasn't this one pass that did it. The wings probably had been repeatedly overstressed by the pilot with similar maneuvers until "she couldn't take any more, Captain."
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So, who gets concerned about flying their old aircraft when it's really rough? I start to think about that 35yr old spar, all those 35yr old rivets, etc., and I start dialing it back. How many whumps and bumps over the years before she gives way?
 
What you're hearing is engineering buffer. Many engineers will include a cushion in their specs so that they're not operating right on the limit. It makes sense if you want to have a reliable and durable product or if you live in tort infested world. I claim my airplane will fly at 100 kts, but I've designed it to fly at 150. If you fly it at 100kts then it should last a long time. Somewhere around 150kts, it will fall apart.

Not every limit is 50%. Especially in aviation where that 50% costs performance.

Bottom line - it's fiction. There is probably some buffer, but you don't know what it is and the only way you'll find out is to discover it when it breaks apart.
 
Bill Jennings said:
So, who gets concerned about flying their old aircraft when it's really rough? I start to think about that 35yr old spar, all those 35yr old rivets, etc., and I start dialing it back. How many whumps and bumps over the years before she gives way?
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That's why you inspect things and NEVER intentionally exceed the limits. Vno and Va are your friends.
 
I'll bet Bob Hoover never exceeded the structural limitations of any of the aircraft he flew in air shows. His loops probably never exceeded 3 g's and his rolls were very smooth and easy on the aircraft. The Partenavia is a capable aircraft if flown within its limitations. Sad to see what happens when you disregard limitations thinking "they always overbuild these things anyway."
 
SoCal RV Flyer said:
That report said that the maximum maneuver load factor, regardless of cargo load, with any flap extension, is 2.0g. It was estimated they were pulling 2.4g, with 50 percent flap extension.
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True but there were some maintenance issues too. The same company had another aircraft lose its wings that same summer. There was a big investigation by the department of interior fire guys in parallel with the NTSB. That company is no longer in business and some major changes came down for how exmilitary aircraft were maintained while operating in the fire environment.

The whole situation was mired in lots of bureaucracy involving private contractors and several federal agencies that made it hard to really know what the heck was going on. From my own research and talking to a few friends that were in the industry when it happened it sounded like a combination of maintenance, operating practices and probably a little of the old NASA style risk acceptance from continued expansion of the operating practices.

To be clear I’m not saying the maintenance was neglected rather the inspection processes were not tailored to the operating environment to effectively find problems before failures occurred.
 
SoCal RV Flyer said:
That report said that the maximum maneuver load factor, regardless of cargo load, with any flap extension, is 2.0g. It was estimated they were pulling 2.4g, with 50 percent flap extension.
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Yeah I may need to retract that statement about exceeding the limits, but as others have pointed out, lots going on there.

Besides the other stuff going on, exceeding 2.0 also isn’t something most pilots would be attuned to, considering most of us have done it in a botched steep turn. Your brain wouldn’t be triggering any warning bells at all.

You’d have to have a very strict training program and a G meter in the aircraft with mandatory monitoring by the PNF to get most pilots to even notice they were encroaching on a 2.0 limitation doing work like that over fires.

The up and downdrafts often would exceed limits, from what I hear from folks who do that type of flying work.
 
denverpilot said:
You’d have to have a very strict training program and a G meter in the aircraft with mandatory monitoring by the PNF to get most pilots to even notice they were encroaching on a 2.0 limitation doing work like that over fires.
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That, or maybe the C-130 just isn't the right tool for the job, given its limitations and the operating environment.
 
SoCal RV Flyer said:
That, or maybe the C-130 just isn't the right tool for the job, given its limitations and the operating environment.
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Possibly. A decision way out of my swim lane. But I suspect that they endure a lot more than 2.0 G in that configuration in combat environments but also don’t have sketchy maintenance in that environment, well usually anyway.
 
P.S. The above is considering that I know someone who was flying one when the entire right inboard flap was blown off by an RPG on takeoff.

Airplane flew an hour or so to a suitably long runway for recovery when they couldn’t get the rest of the flaps up after that.

He said it wasn’t particularly fun to fly it like that but the airframe wasn’t coming apart.
 
Tarheelpilot said:
I don’t think anyone here implied they were weak.
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I know, was just pointing out that sometimes the book numbers and engineering reality can be wildly divergent. In this case, the aircraft exceeded both book and design limits by a substantial amount and survived.
 
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