Border security helo down with fatalities 3/10/2024

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Dave Taylor
I'm intrigued.
Looks like a flat crash with not a lot of forward speed. Not much blade damage either, so rotor speed might've been on the low side at impact.
Engine failure in a hover, and not enough power to keep it in the air on the other one?

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Transmission failure at a high hover (~200 ft) is the most likely cause I can come up with. @Velocity173 would know what’s taught at the schoolhouse nowadays regarding autorotations but I hear it isn’t much—no more full autos to the ground. So there’s another theory that it was a botched auto. Agree that this one makes no sense at first glance.
 
Transmission failure at a high hover (~200 ft) is the most likely cause I can come up with. @Velocity173 would know what’s taught at the schoolhouse nowadays regarding autorotations but I hear it isn’t much—no more full autos to the ground. So there’s another theory that it was a botched auto. Agree that this one makes no sense at first glance.
Current instructor at FT. Novosel (Rucker) here. Autorotations haven’t been taught to the ground in some time. All the helicopters that the students train on are multi-engine. Army regulation prohibits autorotations to the ground in multi-engine helicopters, so all are terminated with power. So yes, most flight school students aren’t particularly skilled at autorotations. We are transitioning to an Army with pilots that will have never practiced a full touch down autorotation.
 
Transmission failure at a high hover (~200 ft) is the most likely cause I can come up with. @Velocity173 would know what’s taught at the schoolhouse nowadays regarding autorotations but I hear it isn’t much—no more full autos to the ground. So there’s another theory that it was a botched auto. Agree that this one makes no sense at first glance.
SWP, LTE, engine / trans failure. Heck, could’ve shutoff the wrong engine and not have been in SE envelope. That’s happened before. RIP.

Not sure about the SE performance in Lakota but you could go all the way down to around 100 ft hover in a Black Hawk and fly out of it. Below that, you’re gonna have to land now with a hard landing. In my experience though, there are a lot of pilots that get taught canned scenarios for SE failure. It’s almost always at cruise and ends with a roll on / run on. They get too accustomed to going to an approved landing site vs land ASAP below you. I used to try and teach my guys the limits of the aircraft and that engine failures don’t always occur when it’s convenient.
 
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Heck, could’ve shutoff the wrong engine and not have been in SE envelope.
Quite possible as in the Duke EC145 accident which had a similar result. Looks like a 72A so very similar to the Duke aircraft. Regardless, its definitely was a high velocity impact given the extensive damage especially on that model. The fact someone survived and it didn't burn is interesting. FYI: this model also has separate engine fuel supply tanks which are filled via elec main pumps.
 
SWP, LTE, engine / trans failure. Heck, could’ve shutoff the wrong engine and not have been in SE envelope. That’s happened before. RIP.
Human failure adds on to mechanical failure like icing on a cake. At least it looks like there’s enough wreckage left to figure this one out. Another reminder that anything with rotors on it can hurt you quick. Sad loss of life and sincere respects to all onboard and their loved ones.
 
Quite possible as in the Duke EC145 accident which had a similar result. Looks like a 72A so very similar to the Duke aircraft. Regardless, its definitely was a high velocity impact given the extensive damage especially on that model. The fact someone survived and it didn't burn is interesting. FYI: this model also has separate engine fuel supply tanks which are filled via elec main pumps.

When I was in Iraq we had a Black Hawk crash while doing high hover training. All they had was an engine chip light but they pulled off the engine at a high hover. They didn’t even think about the fact they weren’t in a SE envelope. OGE, heavy and hot, she ain’t gonna maintain a hover in those conditions. Destroyed the aircraft with injuries.
 
When I went to flight school early 80s probably 50% of landings were one autorotation or another…including low level low airspeed 100ft/40knots for the Scout track, day and NVG. Annual A part check rides also often included an Auto to the ground if the unit IP was checked out and approved.Of course all single engine aircraft…that change quickly with twin engine aircraft simulated to a 50 ft hover seemed to become the norm…
 
Another reminder that anything with rotors on it can hurt you quick
If the wings are traveling faster than the fuselage, it's probably a helicopter - and therefore, unsafe.

And before you all lynch me, joking aside, they are amazingly complex machines which do not tolerate substandard maintenance and poor pilot skills.
 
they are amazingly complex machines which do not tolerate substandard maintenance and poor pilot skills.
I wish that were true. Helicopters are not as fragile as some people think and can be abused on all levels. Unfortunately, bad, lazy owners are not exclusive to the airplane side of the business.
 
When I went to flight school early 80s probably 50% of landings were one autorotation or another…including low level low airspeed 100ft/40knots for the Scout track, day and NVG. Annual A part check rides also often included an Auto to the ground if the unit IP was checked out and approved.Of course all single engine aircraft…that change quickly with twin engine aircraft simulated to a 50 ft hover seemed to become the norm…
I hear you sir. My Army flying era started in 67. Not quite the wild west but close. Kept at it twenty years in the guard and reserve. Many simulated hydraulic failures with run-ons, simulated t/r failures with run-ons, and autorotations as a sport. After flight school when I thought no one was looking I would do some solo straight in autos in a Bell OH-13. This was while waiting on RVN orders. None of it was hard or fear inducing. I guess the Army decided the airframes were getting too expensive to risk, or something. I vote to put @Velocity173 and @Warlock in charge of IERW training. I'm too old (but have good stories).

On a serious note, the emergency procedures seem to have gotten more complicated, and the cockpit panels more cluttered. There are more bells, lights, buzzers, and whistles to contend with or so I'm told. And the guys and gals are getting less flight time to stay proficient with it all. A situation ripe for trouble. I wish them well with all my heart.
 
I hear you sir. My Army flying era started in 67. Not quite the wild west but close. Kept at it twenty years in the guard and reserve. Many simulated hydraulic failures with run-ons, simulated t/r failures with run-ons, and autorotations as a sport. After flight school when I thought no one was looking I would do some solo straight in autos in a Bell OH-13. This was while waiting on RVN orders. None of it was hard or fear inducing. I guess the Army decided the airframes were getting too expensive to risk, or something. I vote to put @Velocity173 and @Warlock in charge of IERW training. I'm too old (but have good stories).

On a serious note, the emergency procedures seem to have gotten more complicated, and the cockpit panels more cluttered. There are more bells, lights, buzzers, and whistles to contend with or so I'm told. And the guys and gals are getting less flight time to stay proficient with it all. A situation ripe for trouble. I wish them well with all my heart.
I’ve always been a fan of autos to the ground but that’s based on single engine aircraft. Still think the Army should’ve gone with a cheap single turbine like the Navy’s TH-73. Oh well.

In twins, I just think the chances are pretty remote for dual engine failure to warrant the training risk. Even loss of tail rotor thrust, while the EP calls for an auto, you could do a mini run / roll on and pull it off without having to auto.
 
This sounds like a well informed crowd. To those of us who know next to nothing about helicopters (other than they appear to violate every known law of the universe and common sense) this conversation sounds much like
 
This is what a helicopter blade does 5 or so times a second. Still want to fly in them?

 
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Now I am retroactively stressed about helo rides I took earlier in life.
 
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This is what a helicopter blade does 5 or so times a second. Still want to fly in them?
Why not? Do you even know what is going on in the video?

Regardless, you didn't even pick the best video....

 
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Now I am retroactively stressed about helo rides I took earlier in life.
Well if they were commercial rides, heli accident rates are roughly half that of non-commercial fixedwing. Most people on POA engage in non-comm fixedwing on a regular basis.
 
I am not talking about anything to do with logic. This is straight up heeby-jeebies.
 
Do you even know what is going on in the video?
No, I have no clue... please explain. While you're there, you can also talk to me about phase lag, why it's not 90 degrees, and how delta-3 plays into this.
Regardless, you didn't even pick the best video....
Maybe I was trying to emphasize the pitch change motion more than the actual blade flap.

Helicopters are not as fragile as some people think and can be abused on all levels.
They can tolerate some abuse. But all it takes is a metal particle about 0.016" trapped between the outer race of a compound bearing/planet gear and the bearing rollers to cause a spall that leads to a fatigue failure in the planet gear which leads to the whole epicyclic module bursting, releasing the entire rotor assembly in the process. And there are more examples of things that would absolutely cause a bad day in a helicopter, while only causing an emergency diversion in the fixed wing world.
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But all it takes is a metal particle about 0.016" trapped between the outer race of a compound bearing/planet gear and the bearing rollers to cause a spall that leads to a fatigue failure
Same thing can happen if said particle gets caught in the critical internals of a Lycoming or Continental engine as well. So whats your point?
And there are more examples of things that would absolutely cause a bad day in a helicopter, while only causing an emergency diversion in the fixed wing world.
And the same can be said for fixed wing as well. You ever check the fatal rates on engine failures between fixed wing and rotor wing? Pretty much more airplane people have a worse day than helicopter people when the engine stops. And that’s just one example. As mentioned above if you compare the commercial helicopter accident rate… where the vast majority of helicopters operate… to the Part 91 non-commercial rate, you have a much better chance of bent metal in a private airplane than in a helicopter. So percentage wise you may want to 2nd guess the next time you sit in your buddy's Cessna.

FYI on your pics. That was the 2nd epicyclic failure with loss of MR assembly for that model/variant aircraft. The OEM blamed bad maintenance on both with their final determination the 225 transmission fell off a truck during transport some 1000 hours previous. The rest of the world found that in both accidents it was more the OEM had exceeded the transmission design limitations. The last I heard there were calls for the OEM to change the type design by clean-sheeting a new transmission that could handle the loads properly. So its a bit more than a single... " metal particle about 0.016" trapped between the outer race ...."
No, I have no clue... please explain. While you're there, you can also talk to me about phase lag, why it's not 90 degrees, and how delta-3 plays into this.
Ha. Your posts sure seem to be big on questions and short on answers. But I’ll amuse you even on the specific rotorcraft items that you conveniently bring up.:rolleyes:

In very general terms... in order for a helicopter to change directions in flight the “rotor disk” must be tilted toward the desired direction. What you are seeing in the video is the “cycle” of one blade out of four reducing pitch and increasing pitch to achieve the disk tilt as inputted from the cyclic stick.

In order for the rotor disk to tilt in the same relative direction as the pilot’s cyclic stick, that cyclic input must happen at a specific point in the rotor’s rotation. The reasons this phase lag can be less or more than 90 degrees depends on a number of factors: rotor design, rotor classification, flap hinge offsets, control speed, blade reaction speed, etc.

In short, when a pilot pushes the cyclic forward, that input is fed to the swashplate mounted on the main transmission via control tubes, mixing bellcranks, and servos. The sw/plate tilts at the prescribed point in the rotor rotation so that the retreating blade will increase to its max required pitch directly opposite of the “requested” direction thus tilting the rotor disk forward. The amount of degrees between the swashplate input and the blade reaching its full required pitch is called the phase lag. So in the video you'll notice the blades achieve full required pitch approximately as it crosses the tailboom which would "lift" the rotor disk and propel the helicopter forward.

If needed, Delta 3 angle will be added into the design equation to stabilize cyclic inputs, reduce external forces on the rotor, and so on by further offsetting the flapping hinge so that any flapping action of the rotor will modify the pitch of the blades. In other words, make it easier to fly. And as I recall, not much Delta 3 in the video design.

Now your turn to answer:
Why is the rotor system in your video more unique in terms of phase lag and Delta 3 than other rotor systems like on a R44 or AS350?

And while you're at it, we’re still waiting on your answer from the “minor alteration thread” on the reason(s) why you completely changed your mind on the topic after vehemently arguing it was not possible in your previous posts?
https://pilotsofamerica.com/communi...ied-avionics-be-so-crappy.146259/post-3493452
 
Same thing can happen if said particle gets caught in the critical internals of a Lycoming or Continental engine as well. So whats your point?
Will that make the wings fall off?

And the same can be said for fixed wing as well. You ever check the fatal rates on engine failures between fixed wing and rotor wing?
See above - show me an example of the wings or tail falling off because of some internal engine failure. Even in the recent example of Continental engines losing their counterweights that wasn't the case.

Ha. Your posts sure seem to be big on questions and short on answers.
Do you even know what is going on in the video?
You seem to be the one asking all the questions. Notice the was no question mark at the end of what I said.

FYI on your pics. That was the 2nd epicyclic failure with loss of MR assembly for that model/variant aircraft. The OEM blamed bad maintenance on both with their final determination the 225 transmission fell off a truck during transport some 1000 hours previous. The rest of the world found that in both accidents it was more the OEM had exceeded the transmission design limitations. The last I heard there were calls for the OEM to change the type design by clean-sheeting a new transmission that could handle the loads properly. So its a bit more than a single... " metal particle about 0.016" trapped between the outer race ...."
At least we're in agreement on how poorly and unethically Airbus handled this, blaming everyone else for things they didn't do. The indentations were actually found in the planet gear fragments found in the first crash, I don't think they found enough planet gear remains from the second one. It was a poor design that was pushed to the limit, but a lot of people still agree that contamination trapped between the rollers and the bearing race portion of the planet gear was the straw that broke the camel's back and allow the crack to start forming. Even if you disagree with that conclusion, we go back to the statement above - show me a fixed wing aircraft where an internal powerplant failure caused the wings to instantly part way with the fuselage.

Helicopters are not as fragile as some people think and can be abused on all levels.
Then go ahead and put an R22 in a zero/negative G condition and come back to tell us about it. Oh wait, you couldn't.

In very general terms...
Surprised that you didn't even mention the advancing/retreading blade part of the explanation. That's as general as it gets. If I had to explain delta-3, I'd use the example of the anti-servo tab on a stabilator (that can also react to wind gusts), which is something easier to grasp for someone that comes from the fixed wing world (even if not perfect). Sometimes more is less, and you have to gauge your audience and use appropriate terminology.

Why is the rotor system in your video more unique in terms of phase lag and Delta 3 than other rotor systems like on a R44 or AS350?
Hingleess rotor with a stiff hub. No real pitch-flap coupling because of the stiff hub, all flapping action happens in the blade cuff after the feathering hinge. This rigid rotor configuration also has a phase angle significantly lower than the articulated rotors. Makes for a very responsive machine, which is why you see the Bo-105 doing all sorts of fast maneuvering at airshows.

And while you're at it, we’re still waiting on your answer from the “minor alteration thread” on the reason(s) why you completely changed your mind
We'll continue that when you quit being selective about how you read things. I told you I agreed with the things you did, but there were things you did not do which I considered to be required in substantiating your finding. I even told you what those things were and where they were addressed in the installation manual. It's like your driving examiner telling you that everything you did during your test was good, but you didn't stop for the pedestrians when making a right turn on red. You failed not because of the things you did, but because of the thing you didn't do.

Read the whole post, edit your response accordingly, and we can continue that conversation in a civilized manner. Same applies here.
 
Not sure why we’re talking about random aerodynamic helicopter features. So a video of a rotor blade constantly changing pitch means they’re dangerous? There’s not even that much stresss involved. The rotating swash plate is spinning around the non rotating. The PC links are just along for the ride. The feathering bearing gets probably most of the stress but they’re not exactly a common replacement part either.

So a rotor separates from a xmsn? Ok, how many times has that happened vs a FW spar breaking? Delta 3 hinge? Another random aerodynamic device that some aircraft have and some don’t. The aircraft I fly doesn’t even have one. It’s not exactly critical to most helicopter main rotor systems.

Read the most current Nall Report. Simple fact is helicopters are on par with their FW counterparts. Any advantage that one has over the other is minor.
 
Will that make the wings fall off?
So you are now implying when any helicopter gets a “… a metal particle about 0.016" trapped between the outer race… “ in the main transmission the “wings” will fall off?

I merely provided an example of a similar mechanical failure mode in airplanes. Didn’t realize you were emphasizing the “wing” aspect at the end of your comment. Context is everything.

Same with your R22 analogy. Negative Gs are an operator failure. Not the aircraft. Same happens to fixed wing except its usually +Gs. There’s been several recent accidents where the wings pulled off due to operator failure. And I think one of them was an engine failure…
Sometimes more is less, and you have to gauge your audience and use appropriate terminology.
Exactly. That’s why I used very general terms. Not too many rotorheads on PoA. However, my reply was only based on what you had questioned even though you forgot the question marks.:rolleyes:

But you do get a gold star for the Bolkow reply.
We'll continue that when you quit being selective about how you read things.
I even told you what those things were and where they were addressed in the installation manual.
So still no answer. Speaking of selective reading… what installation manual are you referring to from my marine radio example? You know the example you stated I couldn’t substantiate in Post 55 and expanded on in Post 72 in that thread? So what changed from Posts 54/55 to Posts 74/75?

I’m all for civilized discussions but it needs to be a two-way interaction in order for it to work.
 
So you are now implying when any helicopter gets a
Aaaaand we're back to our regularly scheduled programming of you putting words in people's mouths. Same as you did in the other thread.
All it takes to develop lung cancer is years of regular smoking, but that does not imply that all smokers will get it.

Helicopters are not as fragile as some people think and can be abused on all levels

same with your R22 analogy. Negative Gs are an operator failure. Not the aircraft.
You're contradicting yourself.

I’m all for civilized discussions but it needs to be a two-way interaction in order for it to work.
Like the ones above? Sure. You first, please.
 
Aaaaand we're back to our regularly scheduled programming of you putting words in people's mouths.
Interesting. So, asking you a question to clarify what you are trying to say about helicopters, now puts words in your mouth?
You realize a simple “no” would have sufficed?

Okay, we’ll keep it simple for you:
What exactly are you trying to say about helicopters with your posts of a video showing a normal helicopter flight function and the pictures of the results from an extremely rare helicopter transmission failure in Norway?
 
Okay, we’ll keep it simple for you:
What exactly are you trying to say about helicopters with your posts of a video showing a normal helicopter flight function and the pictures of the results from an extremely rare helicopter transmission failure in Norway?
What I stated at the beginning of this thread:
they are amazingly complex machines which do not tolerate substandard maintenance and poor pilot skills

And about this bit:
normal helicopter flight
It is normal and understood for people that spent a lot of time around them. I have done an "Introduction to Helicopters" presentation to multiple audiences, and this is the one thing that makes most fixed wing and non-aviation people wary of them. It's not something you notice when you just see them flying around, and a vast majority of people with some level of mechanical knowledge are aware of what cyclic loads do to mechanical things, in terms of fatigue failures and stuff working itself loose.
A B-737 has a design life of about 90000 cycles. Increase that by 20 to account for turbulence-induced cycling of the wings and fuselage on top of the pressurization. A helicopter rotor will go through that many cycles in 100 hours. This then gets used to explain the significant amount of design work put in place so that all those fatigue loads are accounted for to make them the safe machines they are. All that also helps them understand why helicopter maintenance (and therefore their hourly costs) are significantly higher that what they'd see in the fixed wing world for a similarly-sized aircraft.
I have no problem explaining to people how the sausage is actually made, and I like to throw some humor in the mix as well. But they can be very vulnerable to small mistakes, and it takes a lot of extra effort on all fronts to keep them as safe as they are.

And because I like adding a bit of fun into my day to day life, I'll end this with my favorite helicopter definition:

1710686229518.png
 
What I stated at the beginning of this thread:
AV8R_87 said:
they are amazingly complex machines which do not tolerate substandard maintenance and poor pilot skills
And that is the point you continue to miss. Maybe thats the limits of your experience? I don't know. But helicopters are no less tolerant to substandard mx and poor pilot skills than airplanes are. They are not that fragile. In reality, all aircraft “can be very vulnerable to small mistakes" with each model having their own limits. Its not just a helicopter thing. But don’t take my word for it, ask any longtime rotor person to include the ones on PoA. They’ll tell you the same.

What really makes people wary of helicopters is the continued use of myths and misleading statements like the one above or posting videos of common helicopter control movements and following it up with comments like:
“This is what a helicopter blade does 5 or so times a second. Still want to fly in them?”

Perhaps in your next “Introduction to Helicopters” presentation state how on average helicopters are safer to fly in than your average Part 91 privately-owned Cessna or Piper. Or that a helicopter is no more complex than the Delta or United airliners they fly on every day. The results may surprise you.
 
Perhaps in your next “Introduction to Helicopters” presentation state how on average helicopters are safer to fly in than your average Part 91 privately-owned Cessna or Piper. Or that a helicopter is no more complex than the Delta or United airliners they fly on every day. The results may surprise you.
You know what is said about having a little knowledge.
 
I think y’all are just going round and round about this helicopter stuff. Everybody’s in a twist about blades, and I can’t bear to hear anymore about bearings. People are just flapping their gums, leading most of us on while others are lagging behind. Does what I’m saying resonate with anybody? Am I articulating properly?
 
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state how on average helicopters are safer to fly in than your average Part 91 privately-owned Cessna or Piper
You're assuming I'm presenting them as unsafe machines. It's more of a "here's why their design, maintenance and operation requires people to go the extra mile". I know what their safety numbers are and what it takes to get there.

And that is the point you continue to miss.
Do you really believe that an R44 (for example) would have the same safety record if it was maintained and operated the same way most GA fixed wing aircraft are today? Then why are their operational costs around three times that of an equivalent fixed wing?

Am I articulating properly?
I don't know, you seem a bit... rigid :p
 
Do you really believe that an R44 (for example) would have the same safety record if it was maintained and operated the same way most GA fixed wing aircraft are today?
Sure. Its been happening for years in certain circles. It was one of the reasons I stopped working on Robbies. I thought cheap owners were exclusive to airplanes. Did I get that wrong.
Then why are their operational costs around three times that of an equivalent fixed wing?
Simple. Helicopters have life-limited parts and a much smaller market then an equivalent airplane. Remove the time-limit costs and the DOCs between a helicopter and an equal airplane get a lot closer. Surprised you didn’t realize that.

Regardless, all that may change if Hill can get his HX50 off the ground. If his concept works, I think private aviation as a whole may take a much need detour than its present course via LSA, MOSAIC, and the current E/AB market.
 
SWP, LTE, engine / trans failure. Heck, could’ve shutoff the wrong engine and not have been in SE envelope. That’s happened before. RIP.

Not sure about the SE performance in Lakota but you could go all the way down to around 100 ft hover in a Black Hawk and fly out of it. Below that, you’re gonna have to land now with a hard landing. In my experience though, there are a lot of pilots that get taught canned scenarios for SE failure. It’s almost always at cruise and ends with a roll on / run on. They get too accustomed to going to an approved landing site vs land ASAP below you. I used to try and teach my guys the limits of the aircraft and that engine failures don’t always occur when it’s convenient.

Quite possible as in the Duke EC145 accident which had a similar result. Looks like a 72A so very similar to the Duke aircraft. Regardless, its definitely was a high velocity impact given the extensive damage especially on that model. The fact someone survived and it didn't burn is interesting. FYI: this model also has separate engine fuel supply tanks which are filled via elec main pumps.

Trying to figure out how to get sprag, translating, retreating, hanger, settling, droop stops into the conversation…but more so hope they figure out what happened…to absent companions…

My vote is for (1) Velocity's array of probable causes and (2) Bell's reminder of a similar incident with the Duke aircraft. My prayer is that investigators do get a good idea of what happened and more importantly translate that into training and material remedies. This is the best memorial to those lost in yet another helicopter crash. My use of humor was an attempt to defuse the interminable ****ing contest on this thread before it becomes unhinged.
 
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