2 killed in plane crash west of Daytona Beach

Fearless Tower said:
When metal is visibly distorted after a landing, that’s a good indication.

This is the right wing of an Arrow just above the landing gear.
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ouch
 
Not flying an Arrow, nor do I think I will be. But if I were I would like to know it had been inspected for these cracks.
 
PaulS said:
Not flying an ERAU Arrow, nor do I think I will be. But if I were I would like to know it had been inspected for these cracks.
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FIFY.

...and i agree, i wouldn't rent an ERAU arrow either. so yeah, have THEM incur the cost of their own dereliction, instead of subrogating it to me. i thought this was personal responsibility, puritan work ethic no social net of consequence America. oooh you mean deep pockets get the carve out darling treatment? well golly gee, color me naive.

If that sweatshop was flying Bos and they flew a wing off one, you'd see the same nonsense panic befall the cheap seat pharisees on here. But boy would the sparks fly if you told beech owners their personally owned 33/35/36 was a death trap because ERAU broke one. you havent seen mouth frothing tribalism quite like the bonanza cult. cherokee owners are frankly kindergarteners compared to these folks on that account.

at any rate, my point with that is, I dont care if you never fly a pa28, but dont legislate my purview with your panic. thats ultimately my only dog in this fight. i would feel the same way if they were picking on cessnas or beech products. its about holding erau accountable for their behavior, instead of paying off the hall monitor so we all get to wear diapers because our pockets are small.
 
hindsight2020 said:
FIFY.

...and i agree, i wouldn't rent an ERAU arrow either. so yeah, have THEM incur the cost of their own dereliction, instead of subrogating it to me. i thought this was personal responsibility, puritan work ethic no social net of consequence America. oooh you mean deep pockets get the carve out darling treatment? well golly gee, color me naive.

If that sweatshop was flying Bos and they flew a wing off one, you'd see the same nonsense panic befall the cheap seat pharisees on here. But boy would the sparks fly if you told beech owners their personally owned 33/35/36 was a death trap because ERAU broke one. you havent seen mouth frothing tribalism quite like the bonanza cult. cherokee owners are frankly kindergarteners compared to these folks on that account.

at any rate, my point with that is, I dont care if you never fly a pa28, but dont legislate my purview with your panic. thats ultimately my only dog in this fight. i would feel the same way if they were picking on cessnas or beech products. its about holding erau accountable for their behavior, instead of paying off the hall monitor so we all get to wear diapers because our pockets are small.
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I'm not so sure blame can be assigned as an ERAU issue, yet, and I'm leaning toward no, unless they had a maintenance screwup. Hopefully the labs will be able to definitively understand and describe what the failure mechanism is, that would be good for Piper, and owners in general, especially if it weren't a design or material issue. Like I said, I have no plans to fly an arrow, and that's unrelated to this, but if I owned one, I'd want it checked as soon as reasonably possible, that's just me.

I feel bad for people who own these AC and are going through watching this unfold.
 
hindsight2020 said:
FIFY.

...and i agree, i wouldn't rent an ERAU arrow either. so yeah, have THEM incur the cost of their own dereliction, instead of subrogating it to me. i thought this was personal responsibility, puritan work ethic no social net of consequence America. oooh you mean deep pockets get the carve out darling treatment? well golly gee, color me naive.

If that sweatshop was flying Bos and they flew a wing off one, you'd see the same nonsense panic befall the cheap seat pharisees on here. But boy would the sparks fly if you told beech owners their personally owned 33/35/36 was a death trap because ERAU broke one. you havent seen mouth frothing tribalism quite like the bonanza cult. cherokee owners are frankly kindergarteners compared to these folks on that account.

at any rate, my point with that is, I dont care if you never fly a pa28, but dont legislate my purview with your panic. thats ultimately my only dog in this fight. i would feel the same way if they were picking on cessnas or beech products. its about holding erau accountable for their behavior, instead of paying off the hall monitor so we all get to wear diapers because our pockets are small.
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I am not disagreeing with you in the slightest. But a few things need to be clarified. Is this a problem that extends beyond ERAU? Are other training Arrows owned by other schools showing similar problems?

What constitutes excessive use and abuse? A plane use for XC flight in theory does receive less wear and far fewer landing cycles, I want to know how many landing cycles this plane received not its flight hours. Like many jets, should there be regulations about the number of cycles as opposed to airtime?

I am inclined to think this is not a Piper issue or a design problem. The PA28 has existed for 50 years plus years, and over 30k units built. Wings coming off are in the single digits. What precisely is being done to the planes that is accelerating the fatigue? Is it just high landing cycles which is implied here? Is it just training use and ERAU maintenance procedure that are at fault?

Sent from my SM-G950U using Tapatalk
 
PaulS said:
I'm not so sure blame can be assigned as an ERAU issue, yet, and I'm leaning toward no, unless they had a maintenance screwup.
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It’s not the maintenance so much as it’s the use. Again, ERAU is using these airplanes in a way that is probably not what anyone at Piper imagined.

In 10,000 hours (pretty typical of Arrows) an ERAU Arrow will likely see two to three times more landings than your average flight school airplane. That’s a lot of long term abuse on an airplane and that’s the kind of thing that causes metal fatigue which is what the NTSB has found in two ERAU Arrows (the accident airplane one one other).

Now, just basic statistical probability: if an ERAU airplane is seeing 2-3 times more landings, they are also more likely to experience more ‘hard landings’ than the average flight school.

Now, the real truth as to whether this problem is an ERAU issue or airframe design issue won’t really be known until they start doing inspections on other high time (non-ERAU) airplanes.
 
drotto said:
Are other training Arrows owned by other schools showing similar problems?
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We don’t know yet, but I would imagine that someone from the NTSB or FAA is looking into that. I sure hope that they would before publishing some widespread AD.
 
Fearless Tower said:
It’s not the maintenance so much as it’s the use. Again, ERAU is using these airplanes in a way that is probably not what anyone at Piper imagined.

In 10,000 hours (pretty typical of Arrows) an ERAU Arrow will likely see two to three times more landings than your average flight school airplane. That’s a lot of long term abuse on an airplane and that’s the kind of thing that causes metal fatigue which is what the NTSB has found in two ERAU Arrows (the accident airplane one one other).

Now, just basic statistical probability: if an ERAU airplane is seeing 2-3 times more landings, they are also more likely to experience more ‘hard landings’ than the average flight school.

Now, the real truth as to whether this problem is an ERAU issue or airframe design issue won’t really be known until they start doing inspections on other high time (non-ERAU) airplanes.
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Unless it's a material issue or a design issue. While these airplanes have been around for years, changes are constantly made in a manufacturing environment. Different suppliers, different processes, different vendor suppliers, etc. My intuition makes me think something like that happened. Maybe a series of serial numbers might need to be inspected. Who knows. Airplanes should be able to withstand takeoffs and landings, even to excess. Not enough data yet, and as I said, I hope the answer is found.
 
Fearless Tower said:
We don’t know yet, but I would imagine that someone from the NTSB or FAA is looking into that. I sure hope that they would before publishing some widespread AD.
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I agree. Maybe it is ERAU, maybe it's the metallurgy of certain year's production models, or something else. Hopefully they conduct due diligence before issuing anything. They sure seem to be trying to investigate at a much faster pace than usual which I think is a good thing as long as it is thorough and doesn't prematurely jump to conclusions. If I owned an arrow I'd be comfortable flying in the mean time but following very closely.
 
Is the moral of this tragic accident not to fly or buy low wing airplanes from flight schools
 
I am trying to understand why a hard landing might cause metal fatigue. I mean, before I'd expect a spar to experience irreversible damage, I would think that a pilot's back or neck muscles would incur serious injury. I realize that repetitive hard landings by different pilots might be one reason, but really, how many student pilots are really making such hard landings to warrant this concern?
 
sarangan said:
I am trying to understand why a hard landing might cause metal fatigue. I mean, before I'd expect a spar to experience irreversible damage, I would think that a pilot's back or neck muscles would incur serious injury. I realize that repetitive hard landings by different pilots might be one reason, but really, how many student pilots are really making such hard landings to warrant this concern?
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I would bet there are very few student pilots that haven't landed hard at least once. I know that some of my early touch and goes were more accurately referred to as a "crash and dash".

A hard landing every once in a while might not be a big deal, but hundreds or thousands of them could conceivably cause a problem over time.
 
sarangan said:
I am trying to understand why a hard landing might cause metal fatigue. I mean, before I'd expect a spar to experience irreversible damage, I would think that a pilot's back or neck muscles would incur serious injury. I realize that repetitive hard landings by different pilots might be one reason, but really, how many student pilots are really making such hard landings to warrant this concern?
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There may be several mechanisms at play here. It may start as stress corrosion cracking and then transition to fatigue cracking once the cross section is reduced. It could be there is a problem with the metallurgy. It could be a problem with manufacturing and assembly.

The really wonderful thing about metallurgy is that even the experts will argue about the causes.
 
sarangan said:
I am trying to understand why a hard landing might cause metal fatigue. I mean, before I'd expect a spar to experience irreversible damage, I would think that a pilot's back or neck muscles would incur serious injury. I realize that repetitive hard landings by different pilots might be one reason, but really, how many student pilots are really making such hard landings to warrant this concern?
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I’ve flown with some riddle pilots who were making hard landings well after the student pilot phase.

(seriously, I grounded the airplane and they had to do a hard landing inspection)
 
Repeat hard landings that cause the spar to separate should have crumbled the landing gear many times over. Did that happen? Did the landing gear and struts undergo replacements on this aircraft? I guess we'll eventually find out, but something seems odd. I suspect it is a manufacturing fault.
 
sarangan said:
Repeat hard landings that cause the spar to separate should have crumbled the landing gear many times over.
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Why would you expect the landing gear itself to fail before the wing structures the gear is attached to???

Go back in this thread and look at the photo I posted of the top of the wing. The gear on that airplane was absolutely fine. The wing, not so much....
 
Nobody has mentioned that the reports show that FAA found similar cracking in a non-ERAU privately owned aircraft not regularly used for flight training, and with similar total time on the airframe.

I missed it in the report also, but AvWeb pointed it out in a Flash release the same day as this NTSB report came out.

Also if others didn’t notice it, there is a link in the report that leads up a level to a website NTSB has created to store all documents for this particular investigation. (Maybe the other aircraft report was in there? I haven’t had time to look yet.)
 
The report didn’t say who owned the second plane that they found cracks on but it did list the serial number. Looking up the serial number shows that the plane is registered to Embry Riddle. It did state that the plane had a similar number of total airframe hours and cycles and that it was used exclusively for flight training.
 
I remember when a pipeline patrol PA28 lost a wing and there was talk about grounding the fleet or something like that, but they determined it was due to flying in turbulence all the time. Where I used to instruct there were several Arrow wings in permanent storage because they were ruined by rental pilots. The gear is bolted to the spar and twists it upon landing. If it twists far enough the skin wrinkles. If someone tries to land close to the beginning of the runway, say during a short field landing, and hits a snow bank... well, you can imagine. Say it hits the butt end of the concrete...
 
Fearless Tower said:
Why would you expect the landing gear itself to fail before the wing structures the gear is attached to???

Go back in this thread and look at the photo I posted of the top of the wing. The gear on that airplane was absolutely fine. The wing, not so much....
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The impact force from hard landing is transferred through the gear assembly to the wing. The gear needs to withstand the impact before any of that momentum change is transferred to the wing. That's why they make the front end of cars to crumble easily, so that they protect the impact from traveling to the passenger in case of a front end collision. I would assume, and hope, that the wing spar is a lot stronger than the landing gear. If it is really the other way around, that makes no sense to me.
 
sarangan said:
The impact force from hard landing is transferred through the gear assembly to the wing. The gear needs to withstand the impact before any of that momentum change is transferred to the wing. That's why they make the front end of cars to crumble easily, so that they protect the impact from traveling to the passenger in case of a front end collision. I would assume, and hope, that the wing spar is a lot stronger than the landing gear. If it is really the other way around, that makes no sense to me.
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It’s really the other way around in this case.
 
sarangan said:
The impact force from hard landing is transferred through the gear assembly to the wing. The gear needs to withstand the impact before any of that momentum change is transferred to the wing. That's why they make the front end of cars to crumble easily, so that they protect the impact from traveling to the passenger in case of a front end collision. I would assume, and hope, that the wing spar is a lot stronger than the landing gear. If it is really the other way around, that makes no sense to me.
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That’s not physically possible. In order to make the wing structure stronger than the gear itself, the airplane would be so heavy it would never leave the ground.
 
FT, I have to disagree with you for the first time. Piper knows that the PAs they sell ERAU are used for training, and that they’ll be cycled through more hard landings than any other aircraft out there. Knowing that, there really should be extra steps taken for those aircraft. It could be something as simple as putting in their sales contract that they must dispose of the aircraft after a certain number of calendar or tach hours. (Dispose doesn’t mean destroy...more likely sell)

Those planes can only take so much abuse before bad things happen, and you’re never going to catch every problem that arises, like this one, regardless of how close you look.
 
unfortunately.....the lawyers will take care of ERAU now. After this....It should sort itself out....;)
 
denverpilot said:
FAA found similar cracking in a non-ERAU privately owned aircraft not regularly used for flight training, and with similar total time on the airframe.

I missed it in the report also, but AvWeb pointed it out in a Flash release the same day as this NTSB report came out.
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Where do you see that? All I see is "The plane inspected had a similar number of total airframe hours and cycles and was used exclusively for flight training of students"
 
I saw this also. It said nothing about where the other affected plane came from. I though it was logical that it would be another of their planes, as well as the other 9 checked. Since it is a high volume school the FAA is also investigating their usage and maintenance procedures. This is not just about Piper.

I would be surprised if the FAA does not decided to go look at some random PA28R's at some point. And as someone said above, the serial numbers of the planes check do seem to be ERAU registrations.

Sent from my SM-G950U using Tapatalk
 
Clark1961 said:
The really wonderful thing about metallurgy is that even the experts will argue about the causes.
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True in some cases. But in my experience, of all the investigative methods out there, metallurgy is one of the more precise when tracking down the causes of failure. In this case, with such a "clean" sample, the experts will provide pictures of the initial point/start of the failure, any additional issues, and include the approximate number of cycles it flew before failure. And I believe since this accident has priority we will know some details sooner than later.
 
Bell206 said:
True in some cases. But in my experience, of all the investigative methods out there, metallurgy is one of the more precise when tracking down the causes of failure. In this case, with such a "clean" sample, the experts will provide pictures of the initial point/start of the failure, any additional issues, and include the approximate number of cycles it flew before failure. And I believe since this accident has priority we will know some details sooner than later.
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I cannot address your experience. I can caution folks to understand that when an expert stands up and says "this is..." that expert is only offering an opinion and that opinion frequently ignores many aspects of the particular thing upon which the expert is pontificating. Many lawyers and expert witnesses have made tidy sums of money because of these expert opinions. Metallurgy is particularly susceptible because one expert identifies a crack initiation point at some defect and says "ah ha", the next expert reviews the test coupon properties and says "ah ha", and then a design guy reviews the loads and says "ah ha". After that it gets complicated.
 
denverpilot said:
Who are these people who say “ah ha”? I usually say, “holy ****!” ;)
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It goes with the PhD and the expert witness fees. The judge doesn’t want to hear “holy sheet” in court. Guess he never heard of the shroud of Turin but that’s beside the point.
 
Clark1961 said:
It goes with the PhD and the expert witness fees. The judge doesn’t want to hear “holy sheet” in court. Guess he never heard of the shroud of Turin but that’s beside the point.
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Immaculate conception sounds nicer than “holy f***!”, too. You PhDs is smart and stuff like that. :)
 
Fearless Tower said:
The gear on that airplane was absolutely fine. The wing, not so much
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This has been my main gripe (outside of one door) on the PA28... the gear.. that stubby little oleo strut goes straight into the wing. Many other fixed gears transfer the load more directly into the wingbox and airframe core as opposed to somewhere out on the wing causing a massive momentary bending moment at the wing root. Look at Grummans, Cirrus, TTx, heck even the Piper Tomohawk and current Piper Sport LSA have a gear system that absorbs much more of that bending moment itself and transfer it right in the wing box / fuselage (kind of like a Cessna highwing) rather than punching it straight up into the wing

I seem to recall that this is where Boeing and McDonnel Douglas differed as well. The Boeing gear is not directly on the spar, so in the case of a very hard landing (like the BA 777 that had a total power loss and landed short) the gear goes up through the wing, rather than shearing the wing off. I recall at least one (maybe more?) MD-11 accidents were a hard landing turned into death and destruction from the wing itself coming off

sarangan said:
The gear needs to withstand the impact before any of that momentum change is transferred to the wing
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That's physically impossible the way the gear is set up, that force will be transferred one way or another up into the wing. The oleo strut can be made softer, etc., to help dissipate that energy, but ultimately it is going to be transferred up into the wing given its current design. Piper should have used Tomohawk, Piper Sport, Grumman, Cirrus, etc., style gear. I imagine that would have been lighter and easier on maintenance too

Gerhardt said:
Piper knows that the PAs they sell ERAU are used for training, and that they’ll be cycled through more hard landings than any other aircraft out there. Knowing that, there really should be extra steps taken for those aircraft.
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I totally agree. The idea that "well this plane is used for training so the wings fall off at 7,000 hrs" is absurd. I have read that the PA28 airframe life is 62,900 hrs. **If an airplane is operated within its envelope then it should stay in one piece throughout its design life span** Sure, hard landings are an exception, but they DO happen.. and for a plane designed as a trainer as its primary role you would expect it to stay together, or be built with better failure modes that have a sheer pin between the wing and gear, or a different style gear altogether

I mean, how hard is ERAU "abusing" these planes? I've heard some really passionate opinions about them.. but how does such a large flight school actually beat on their equipment that hard? You would think with a large organization the training culture and curriculum would be a well documented and professional outfit. Some people here make it seem like ERAU is a group of teenagers thinking they're Top Gun and over G'ing the planes on flights and slamming them down onto the runway. I mean, outside of some solo and XC time aren't most of the ERAU planes flown with an instructor?

Remember also that even given the gear design that even when that plane is sitting on the ground that wing root joint is still under load.. so even when it is not flying and just parked happily that material is slowly but surely fatiguing away.. got a big fat dude that throws himself down onto the seat and the whole plane shudders? You guessed it, that 250 lbs just sent an additional momentary load straight out into the wing

I really like Pipers and their whole PA28 line flies really nice, it is a true, honest, sure footed, and predictable plane that makes a great instrument platform. Piper hit a lot of things out the park on that plane. But ever since I've been flying them (almost two decades at this point) the gear and wing attachment always bothered me
 
Clark1961 said:
Many lawyers and expert witnesses have made tidy sums of money because of these expert opinions.
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It is not the paid expert witnesses I refer to, but the staff lab techs who produce the reports that your paid experts offer their varying opinions on before the court. And in most cases, any potential plaintiff experts are not even invited to the party until after the investigation is over and a claimant is filed. So they must rely on the same lab tech report.

The science part of metal research is very exacting down to the point of origin. These reports are detailed enough that even a lay-person with a basic understanding of the item can follow the path of failure. Pull any similar metallurgy report from the NTSB public docket and the detail is self-explanatory.

But to get back on topic it will be interesting to read the full lab report from this accident. And if the feds follow normal practice we'll will get a gist of that report if and when an AD is issued. However, you are correct that once the full report is out (which usually shows a single point of origin) that when we enter the tort litigation arena then one expert will state the point of origin was due to faulty maintenance, with the next expert stating fault was improper manufacture, etc. etc.

At least that is my experience.
 
Bell206 said:
It is not the paid expert witnesses I refer to, but the staff lab techs who produce the reports that your paid experts offer their varying opinions on before the court. And in most cases, any potential plaintiff experts are not even invited to the party until after the investigation is over and a claimant is filed. So they must rely on the same lab tech report.

The science part of metal research is very exacting down to the point of origin. These reports are detailed enough that even a lay-person with a basic understanding of the item can follow the path of failure. Pull any similar metallurgy report from the NTSB public docket and the detail is self-explanatory.

But to get back on topic it will be interesting to read the full lab report from this accident. And if the feds follow normal practice we'll will get a gist of that report if and when an AD is issued. However, you are correct that once the full report is out (which usually shows a single point of origin) that when we enter the tort litigation arena then one expert will state the point of origin was due to faulty maintenance, with the next expert stating fault was improper manufacture, etc. etc.

At least that is my experience.
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It appears that you have missed my point entirely which is that the precise identification of the crack initiation site may have nothing to do with the ultimate failure. A simple example which may be relevant here is that if the ultimate design load was exceeded it doesn't matter where the crack started because the structure was going to fail some way some how.
 
Tantalum said:
......

I mean, how hard is ERAU "abusing" these planes? I've heard some really passionate opinions about them.. but how does such a large flight school actually beat on their equipment that hard? You would think with a large organization the training culture and curriculum would be a well documented and professional outfit. Some people here make it seem like ERAU is a group of teenagers thinking they're Top Gun and over G'ing the planes on flights and slamming them down onto the runway. I mean, outside of some solo and XC time aren't most of the ERAU planes flown with an instructor?
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good question....it might not be abuse as much as the flight profiles are intense & tough.....like take-off and landings only in certain aircraft with air work and x-country in another. That kind of intense use is not the norm across the PA-28 fleet nation wide. It would be a shame to implement some corrective action in an AD for all to perform.
 
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