EC 130 down at the Grand Canyon
A few people here and there is a small price to pay.
Keep calm and carry on.
Keep calm and carry on.
I think we can all agree it has seriously reduced the number of deaths from survivable accidents.
In this day and age there is no excuse for putting something as simple as a bladder tank in an aircraft - apart from money, that is.
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That's actually not entirely accurate in the US. Because, you know, this is 'merica, baby. While Robinson did issue a factory service bulletin (SB) in Dec 2010, SB's are not mandatory for FAA Part 91 op's without an attendant AD, only Part 135 op's. And the FAA never issued an AD for this. Hell, technically you could even get away with it under Part 135 if you can get the FAA to sign off on your maintenance program, but I don't believe that anyone has tried that. So there are still a finite number of 44's and 22's flying around without bladders in Part 91 service.
It has been mandatory for some time in most civilised parts of the world
The FAA get a lot right but they seem determined to get a lot wrong.
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In this case it is easy to suspect that both Robinson and the FAA believed that between all the Astros having to get the hydraulic refit and the 12 year overhaul cycle, most owners would ultimately get the bladders by default. Since essentially all the Astros had to go to the Robinson factory for the refit Robinson would have forced that issue. But some number of Ravens built between when they were introduced in 2000 and the 2010 SB, even potentially having undergone more than one overhaul cycle, don't have them because the owners didn't/don't want to incur the cost. The sheet metal work, and the subsequent requirement for a paint job, drives the cost up quite a bit. Not saying it's right or wrong. It does make you wonder exactly how many are left like that.
In its final report into the incident, the National Transportation Safety Board (NTSB) in the US concluded tailwinds, potential downdrafts and turbulence were the probable cause of the loss of control of the aircraft.The "most significant factor" affecting survival of those on board the helicopter was the post-crash fire, according to the findings.
The aircraft was "not equipped, nor was it required to be equipped, with a crash-resistant fuel system".
After the crash, the helicopter company announced that it would fit crash-resistant tanks to its fleet.
https://www.bbc.com/news/uk-england-sussex-55674015
The aircraft was "not equipped, nor was it required to be equipped, with a crash-resistant fuel system".
After the crash, the helicopter company announced that it would fit crash-resistant tanks to its fleet.
https://www.bbc.com/news/uk-england-sussex-55674015
The report basically accepts that a freak wind caused the accident.
Maybe doing the same thing again and again without a problem causes complacency to creep in? A priori, the approach to the west helipads would be flown with visual reference to the terrain. Add a strong tailwind or gust, and take your eyes a moment off the airspeed, and within a second he might have lost effective translational lift.
However freaky the gust, it wasn't entirely unexpected.
The seventh pilot to land entered the canyon at 1709. During his approach to the west pads, his intended destination, he recalled that the helicopter's tail swung rapidly due to strong winds and he applied significant right pedal and crabbed the helicopter to maintain the approach.
The last helicopter to land before the accident entered the canyon at 1710 and touched down about 2 minutes before the accident occurred. The pilot had experience flying in mountainous terrain, knew of the presence of 15-20 kt winds from the east, and thus anticipated windshear during the approach. While turning toward the west pads, he experienced a strong wind that swung the nose of the helicopter about 90° to the left.
The last helicopter to land before the accident entered the canyon at 1710 and touched down about 2 minutes before the accident occurred. The pilot had experience flying in mountainous terrain, knew of the presence of 15-20 kt winds from the east, and thus anticipated windshear during the approach. While turning toward the west pads, he experienced a strong wind that swung the nose of the helicopter about 90° to the left.
Maybe the mishap pilot did everything possible to avoid the crash, to no avail. There is something strange though:
A pilot on the ground at the landing site reported that the accident helicopter began to decelerate as it approached the landing pads and entered a nose-up attitude, then turned left toward the landing pads, transitioned through several pitch oscillations, and drifted aft.
Either way, the pilot coming in just 5 min before the mishap pilot, reported that he managed to handle the situation as per text book (increase airspeed, give the Fenestron the boot). Somewhere else we read that this pilot now has misgivings that he didn't alert is fellow pilot. I would feel the same. Here is what this pilot told the accident investigators:
The airspeed rapidly decayed and it required all of his effort to maintain control of the helicopter. As the helicopter began to descend, he increased collective to arrest the descent and was able to maintain control by pushing the cyclic forward and right to increase airspeed while applying full right pedal to keep the nose straight. He successfully landed the helicopter on one of the west pads.
The mishap pilot had 2,400+ HRS TTRW, of which 1,000+ on type. The latter acquired over the past four years flying for this operator. However, he only flew 2 HRS in the past 30 days before the accident. The report doesn't dwell on this any further.
Another point that puzzles me is that 2,396 HRS of 2,423 HRS TTRW were PIC. That only leaves 27 HRS dual instruction over his entire flying career. These are also the numbers stated in the "Accident Report" (not the investigation report, but the initial report to the FAA). Don't they record recurrent training and line checks as "Dual"?
So what do we learn?
Last edited by Hot and Hi; 17th Jan 2021 at 19:32. Reason: Spelling
Another point that puzzles me is that 2,396 HRS of 2,423 HRS TTRW were PIC. That only leaves 27 HRS dual instruction over his entire flying career. These are also the numbers stated in the "Accident Report" (not the investigation report, but the initial report to the FAA). Don't they record recurrent training and line checks as "Dual"?
In the US, once you have a certificate or rating for an aircraft type, then ALL time flown after that is logged as PIC. If there is an instructor on board and you are recieving instruction then it would be logged as PIC and Dual. Therefore those numbers are correct---he would have recieved 27 hours dual non-PIC only during his initiall PPL training.
Problem is, before they can issue an AD, by law, the FAA needs a cost/benefit analysis to show that the benefit outweighs the cost. That's always tricky for crashworthiness changes since they only come into play after the aircraft has already crashed - makes it's hard to define lives saved. It's much easier for airworthiness changes since you can say it'll prevent a crash (note that this isn't the case for new regulations as they only apply to new certifications - not retrofit - no cost/benefit required).
You would be hard pressed to find a 135 set of ops spec that do not make so called mandatory service bulletins for engine, emergency equipment, and for airplanes their propellers a requirement under said Ops. Specs. Many also include ,mandatory airframe bulletins but it depends on who is doing the approving on the FAA side.
They did not quote dual, they quoted TT and PIC.
In the US, once you have a certificate or rating for an aircraft type, then ALL time flown after that is logged as PIC. If there is an instructor on board and you are recieving instruction then it would be logged as PIC and Dual. Therefore those numbers are correct---he would have recieved 27 hours dual non-PIC only during his initiall PPL training.
In the US, once you have a certificate or rating for an aircraft type, then ALL time flown after that is logged as PIC. If there is an instructor on board and you are recieving instruction then it would be logged as PIC and Dual. Therefore those numbers are correct---he would have recieved 27 hours dual non-PIC only during his initiall PPL training.
Understandably, the emotional response here focusses mostly on crash-resistant fuel tanks, as in this case this is likely to have made a significant difference to an otherwise well-survivable accident. And because the idea of passengers burning to death is so horrendous.
On the other hand, the fuel tank issue is rather coincidental, as it has nothing to do with the cause of the accident. And amongst the bad luck of the post crash fire it was sheer luck that the mishap helicopter didn't roll down the ravine, killing all on board by blunt force trauma, even without a fire.
Do we accept that the accident itself was caused by an Act of God, as the report seems to suggest?
- Do we then accept that the airframe in question has a design fault that could even take out experienced pilots? This so far has been the exclusive domain of another, American OEM whose products are so often belittled here for exactly that reason.
- Or do we say that the wind situation the mishap pilot encountered was in all likelihood not significantly different from what the two pilots in the 10 min before him encountered? Challenging, but ultimately they was able to deal with that.
I don't see that we have another alternative: Either is was pilot error, or the anti-torque device of the EC130 doesn't have sufficient authority. (Or both of course.)
We are taught to land into the wind for a reason. And not just because birds do it instinctively. So we all must understand something: You can land a helicopter with a strong tailwind, but it take meticulous planning and skill...and even maybe a measure of luck. You have to be ready for anything...but you especially have to be ready for the thing to want to swap ends on you if you let the airspeed get low. You can get away with some crazy antics in a helicopter when you're into the wind. But downwind? All bets are off.
The Astar pilot had reportedly been into that particular LZ *581* times! So it's not like it was inexperienced and unfamiliar with operations down there. This time, he just made a poor choice of approach profile - for some reason. Hey, we're human; we screw up sometimes. With a windsock at the LZ, it would be pretty poor airmanship to not check it out before commencing the approach. And if you look at the pictures taken at the site at the time of the accident, you'll see the windsock sticking straight out. Me (and probably you too), I would want to land *INTO* the wind in such a case.
We've all heard of pilots using the infamous "rogue gust of wind!" excuse for why they crashed a perfectly good helicopter. In this case, the pilot upped the ante and reported a "violent" gust of wind! Well...if you knew the weather down in that canyon was strong and gusty, and you decide to land downwind, shouldn't you be prepared for that? I mean, what do they pay us for?
Let's call it what it was: Pilot error.
Ultimately Yep.....
I don't classify it as pilot error (in addition to the accident of this topic, here are 3 similar accidents. There could be more, but currently the NTSB search function is limiting result to post 2010). Why, especially in today’s era, do we accept designs that are prone to LTE. I thought this deficiency was conquered in the 80s?
https://app.ntsb.gov/pdfgenerator/Re...mmary&IType=LA
https://app.ntsb.gov/pdfgenerator/Re...mmary&IType=CA
https://data.ntsb.gov/Docket/?NTSBNumber=CEN15FA164
https://app.ntsb.gov/pdfgenerator/Re...mmary&IType=LA
https://app.ntsb.gov/pdfgenerator/Re...mmary&IType=CA
https://data.ntsb.gov/Docket/?NTSBNumber=CEN15FA164
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According to the paper I posted in this link:
https://www.pprune.org/rotorheads/636375-r44-crashed-alps.html#post10916510
LTE is a myth, and helicopters that meet certification requirements always have plenty of anti-torque authority.
A few posts down from that one there is also a link to a video of the author's presentation but the paper by itself is better.
https://www.pprune.org/rotorheads/636375-r44-crashed-alps.html#post10916510
LTE is a myth, and helicopters that meet certification requirements always have plenty of anti-torque authority.
A few posts down from that one there is also a link to a video of the author's presentation but the paper by itself is better.
Thanks to the link reminder, that was indeed a good paper.
I think the essence of a good pilot, is to already predict the chain of event, and be ready to push that pedal (or decrease that collectives) because you saw it coming
I remember very early in my training:
was flying downwind on the upwind side of a hill, the aircraft was so gentle it was beautiful,
went around the hill, on the downwind side, the aircraft started sinking toward the ground
added a bunch of collective and the tail started to spin around, almost did a full turn (we were still downwind)
I didn't see it anything coming, missed all the signs passing by me, yet the fix was soo simple, Instructor just push the collectives slightly down and gently steer us toward the valley
Since then I have never tried to fight nature with collective, its a losing battle.
I think the essence of a good pilot, is to already predict the chain of event, and be ready to push that pedal (or decrease that collectives) because you saw it coming
I remember very early in my training:
was flying downwind on the upwind side of a hill, the aircraft was so gentle it was beautiful,
went around the hill, on the downwind side, the aircraft started sinking toward the ground
added a bunch of collective and the tail started to spin around, almost did a full turn (we were still downwind)
I didn't see it anything coming, missed all the signs passing by me, yet the fix was soo simple, Instructor just push the collectives slightly down and gently steer us toward the valley
Since then I have never tried to fight nature with collective, its a losing battle.
Last edited by Agile; 20th Jan 2021 at 01:34.
According to the paper I posted in this link:
https://www.pprune.org/showthread.php?p=10916510
LTE is a myth, and helicopters that meet certification requirements always have plenty of anti-torque authority.
A few posts down from that one there is also a link to a video of the author's presentation but the paper by itself is better.
https://www.pprune.org/showthread.php?p=10916510
LTE is a myth, and helicopters that meet certification requirements always have plenty of anti-torque authority.
A few posts down from that one there is also a link to a video of the author's presentation but the paper by itself is better.
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In the discussion of this accident in one of the Facebook rotorcraft groups, a guy - presumably a pilot but you never know - said, "I believe the primary cause of this accident was LTE."
It seems that there is a whole generation of pilots who've come to accept the myth of "Loss of Tail Rotor Effectiveness." They believe that the tail rotor can somehow get into a condition ("cavitation?") where it stops producing thrust and the helicopter will spin around like a top even with full power-pedal applied. This of course is nonsense. But pilots are loathe to apply and hold *full* pedal, even if it's called for. Because...I guess...if you do that in a hover when you're near a power limit, you could easily have an engine temperature or torque exceedance. And nobody wants that! But it's hard to understand why pilots would accept a crash as opposed to saving their skin.
The thing to remember...well, *two* things to remember are that: 1) The helicopter is a big weathervane and wants to point itself into the wind; and 2) As long as it's spinning, the tail rotor *never* stops working. If more pilots would just understand these two basic things, I'd bet there'd be fewer crashes where the pilot gets out and says, "It was LTE! The aircraft failed me!"
It seems that there is a whole generation of pilots who've come to accept the myth of "Loss of Tail Rotor Effectiveness." They believe that the tail rotor can somehow get into a condition ("cavitation?") where it stops producing thrust and the helicopter will spin around like a top even with full power-pedal applied. This of course is nonsense. But pilots are loathe to apply and hold *full* pedal, even if it's called for. Because...I guess...if you do that in a hover when you're near a power limit, you could easily have an engine temperature or torque exceedance. And nobody wants that! But it's hard to understand why pilots would accept a crash as opposed to saving their skin.
The thing to remember...well, *two* things to remember are that: 1) The helicopter is a big weathervane and wants to point itself into the wind; and 2) As long as it's spinning, the tail rotor *never* stops working. If more pilots would just understand these two basic things, I'd bet there'd be fewer crashes where the pilot gets out and says, "It was LTE! The aircraft failed me!"
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I fly almost exclusively a 120 - fenestron - though learned in a 44.
It has more than adequate thrust from the tail rotor.
However it is a fenestron, not a simple blade, and so the pilot has to understand how it works and what it will do when you disrespect it. compared to a simple blade design
1. Just as much "push" available
2. To access it will likely require significantly more pedel than a non-fenestron pilot will expect
3. There is also a "Big Wing" in the design. That introduces benefits (unloading the fan in forward flight, increased stability into wind) and issues (air flow angle of attack exceeds 20 degrees and suddenly you lose all assistance from the "wing" (it stalls), and it is a bigger "rudder" to drive you around if you get the wind wrong on the tail).
Suffers from LTE - no
Harder to fly - no, just different. If you trained G2 and moved on to 120 /130 I doubt you would even understand what the fuss is about
More dangerous - certainly not. I happily put the world's most precious cargo (to me) in one
In this case, landing down wind in gusty conditions without adequate planning was asking for it (in any helicopter, I think)
It has more than adequate thrust from the tail rotor.
However it is a fenestron, not a simple blade, and so the pilot has to understand how it works and what it will do when you disrespect it. compared to a simple blade design
1. Just as much "push" available
2. To access it will likely require significantly more pedel than a non-fenestron pilot will expect
3. There is also a "Big Wing" in the design. That introduces benefits (unloading the fan in forward flight, increased stability into wind) and issues (air flow angle of attack exceeds 20 degrees and suddenly you lose all assistance from the "wing" (it stalls), and it is a bigger "rudder" to drive you around if you get the wind wrong on the tail).
Suffers from LTE - no
Harder to fly - no, just different. If you trained G2 and moved on to 120 /130 I doubt you would even understand what the fuss is about
More dangerous - certainly not. I happily put the world's most precious cargo (to me) in one
In this case, landing down wind in gusty conditions without adequate planning was asking for it (in any helicopter, I think)
Possibly compounded by the terrain. These ravines can act as funnels if the wind is pointing straight onto them and create much stronger local winds. If I interpret the situation correctly it went out of control pretty much in the middle of that funnel/ravine.