EC225 crash near Bergen, Norway April 2016
It seems surprising that after 5 years there has not been a test to destruction of the gear box design involved.
Afaik, we have a plausible failure sequence, but no firm take away conclusions that would allow future designers to avoid a similar disater.
Can anyone shed light on the state of play in this area?
Afaik, we have a plausible failure sequence, but no firm take away conclusions that would allow future designers to avoid a similar disater.
Can anyone shed light on the state of play in this area?
You have pretty well summed it up.
It’s likely, in any operation where the people on board, IE pilots/pax, have any say, that an EC225 won’t be used.
It seems surprising that after 5 years there has not been a test to destruction of the gear box design involved.
AFAIK, we have a plausible failure sequence, but no firm take away conclusions that would allow future designers to avoid a similar disater.
Can anyone shed light on the state of play in this area?
AFAIK, we have a plausible failure sequence, but no firm take away conclusions that would allow future designers to avoid a similar disater.
Can anyone shed light on the state of play in this area?
You can test the gearbox to destruction but that would be pointless unless you had some idea as to what you would do to initiate it.
This is a seriously deep rabbit hole!!
And yet look at that recent report about the S92 in Canada. Ok they missed the sea by 13’ but it was very close. And not the first time. The 225 may have a quickly-detachable rotor head but the autopilot made the aircraft much safer in the face of loss of SA/pilot incompetence. But as ever, unfortunately humans don’t evaluate risk logically or rationally.
And yet look at that recent report about the S92 in Canada. Ok they missed the sea by 13’ but it was very close. And not the first time. The 225 may have a quickly-detachable rotor head but the autopilot made the aircraft much safer in the face of loss of SA/pilot incompetence. But as ever, unfortunately humans don’t evaluate risk logically or rationally.
Look at G-REDU, that flew itself straight in... no upper modes...
And yet look at that recent report about the S92 in Canada. Ok they missed the sea by 13’ but it was very close. And not the first time. The 225 may have a quickly-detachable rotor head but the autopilot made the aircraft much safer in the face of loss of SA/pilot incompetence. But as ever, unfortunately humans don’t evaluate risk logically or rationally.
And yet look at that recent report about the S92 in Canada. Ok they missed the sea by 13’ but it was very close. And not the first time. The 225 may have a quickly-detachable rotor head but the autopilot made the aircraft much safer in the face of loss of SA/pilot incompetence. But as ever, unfortunately humans don’t evaluate risk logically or rationally.
The thing that resonates with me is: If the rotor head departs, no matter what, no matter how good or lucky you are as a pilot, you have a few seconds of terrifying life left.
Most of us believe, rightly or wrongly, that catastrophic incompetence can be avoided, or even recovered from, as in the S92 near miss referenced.
I agree about the risk evaluation not necessarily being logical.
The thing that resonates with me is: If the rotor head departs, no matter what, no matter how good or lucky you are as a pilot, you have a few seconds of terrifying life left.
Most of us believe, rightly or wrongly, that catastrophic incompetence can be avoided, or even recovered from, as in the S92 near miss referenced.
The thing that resonates with me is: If the rotor head departs, no matter what, no matter how good or lucky you are as a pilot, you have a few seconds of terrifying life left.
Most of us believe, rightly or wrongly, that catastrophic incompetence can be avoided, or even recovered from, as in the S92 near miss referenced.
It's been a long while since I strapped into a 225, but I dont think this is entirely accurate. The 225 flown without any upper modes would still get you into trouble. The hidden protections would only help with at least 1 upper mode engaged. So in this instance (I dont think the 92 had any upper modes engaged) then the outcome may have been the same. (Assuming the 225 gearbox could take the ramp up in torque that the 92 took)
Look at G-REDU, that flew itself straight in... no upper modes...
Look at G-REDU, that flew itself straight in... no upper modes...
Of course since I left the N Sea in 2013 things have moved on to the 175 and 189, which probably have good autopilots (well the 175 certainly does) but then again, have the fatal design flaws on those new aircraft manifested themselves yet? Who knows!
you are correct on a simplistic level. But the point is that the 225’s upper modes are so capable that they tend to get used eg on a visual segment post-MAP, and any sensible operator encourages or mandates it. The S92s upper modes can’t be used at low IAS and anyway are quite soggy, so it’s back to the human and fallible pilot by necessity.
Of course since I left the N Sea in 2013 things have moved on to the 175 and 189, which probably have good autopilots (well the 175 certainly does) but then again, have the fatal design flaws on those new aircraft manifested themselves yet? Who knows!
Of course since I left the N Sea in 2013 things have moved on to the 175 and 189, which probably have good autopilots (well the 175 certainly does) but then again, have the fatal design flaws on those new aircraft manifested themselves yet? Who knows!
Anyway, thread drift etc...
.......things have moved on to the 175 and 189, which probably have good autopilots (well the 175 certainly does) but then again, have the fatal design flaws on those new aircraft manifested themselves yet? Who knows!
As an Aircraft as a whole - I really like it (AW189). Hoping for no undiscovered “fatal design flaws”.
I keep thinking that SpaceX appears to have transformed launch economics by focusing on robustness rather than peak performance.
Is a similar shift in philosophy potentially possible in the helicopter market?
That is pretty disappointing. Is there a broader trend, that the more recent helicopters are less durable?
I keep thinking that SpaceX appears to have transformed launch economics by focusing on robustness rather than peak performance.
Is a similar shift in philosophy potentially possible in the helicopter market?
I keep thinking that SpaceX appears to have transformed launch economics by focusing on robustness rather than peak performance.
Is a similar shift in philosophy potentially possible in the helicopter market?
For safety: Obviously.
Then with fleet information gleaned over time from inspections and testing of “time EX” gearboxes (for example), TBO’s could often (usually) be extended.
For reduced operating costs: Obviously.
Anecdotally, increased competition and greed now mean pushing everything to it’s limit*. For the brochure. Then, when a few fail, reducing the TBO is the easy, and potentially profitable way out, for the manufacturer.
EC225’s had a MTOW of 11200Kg*. What did the Puma start out at 8350Kg? (Or less? - I never flew a non “Super” Puma.)
Last edited by Twist & Shout; 3rd May 2021 at 21:37. Reason: 300kg reduction in MTOW - thanks.
When I started flying Puma in 1971 the MAW was 6,400 kgs. and the gearbox life was 900 hrs. Around 1973 the AUW was increased to 6,700 kgs and at the same time they initiated the CAAP Programme. (Component advanced ageing programme)
The was a programme to fly selected aircraft; two RAF and four French Army, one hundred hours a month each with the gearboxes stripped every two hundred hours so as to extend the fleet's life to 1800hrs.
This was successful so the Puma entered the civilian market. I flew the 'J' model with plastic blades up to 7.400 kgs.
The was a programme to fly selected aircraft; two RAF and four French Army, one hundred hours a month each with the gearboxes stripped every two hundred hours so as to extend the fleet's life to 1800hrs.
This was successful so the Puma entered the civilian market. I flew the 'J' model with plastic blades up to 7.400 kgs.
As I mentioned in a previous post: Too much new wine in old bottles.
I had a chance to convert to them late in my working life but being one of HC's 'Old Dinosaurs' I didn't like the way it was operated so I backed out and stayed on the 332L1.
I had a chance to convert to them late in my working life but being one of HC's 'Old Dinosaurs' I didn't like the way it was operated so I backed out and stayed on the 332L1.
Join Date: Mar 2020
Location: Germany
Posts: 13
Likes: 0
Received 0 Likes
on
0 Posts
As we all know it was the same crack in a second stage planet gear on G-REDL on 01.04.2009 and LN-OJF on 29.04.2016, which caused the MR to separate. After all the measures taken, like reduction of the MGB TBO to roughly one third of the initial TBO, installation of another mag plug, flight ban on one type of planet gear etc etc, the 225 could be considered as safe for flight (again), imho. Especially the more frequent scheduled MGB removals drive the costs per flight hours, but who cares.
However, after thousands of engineer hours and millions of Euros for the regarding technical investigation, the reason why a crack (twice) could propagate inside the gear rim, undetected by e. g. HUMS and the classical methods like mag plug and filter, remains still unknown. Strange, isn't it?
However, after thousands of engineer hours and millions of Euros for the regarding technical investigation, the reason why a crack (twice) could propagate inside the gear rim, undetected by e. g. HUMS and the classical methods like mag plug and filter, remains still unknown. Strange, isn't it?
Join Date: Oct 2002
Location: All over the place
Posts: 231
Likes: 0
Received 0 Likes
on
0 Posts
As we all know it was the same crack in a second stage planet gear on G-REDL on 01.04.2009 and LN-OJF on 29.04.2016, which caused the MR to separate. After all the measures taken, like reduction of the MGB TBO to roughly one third of the initial TBO, installation of another mag plug, flight ban on one type of planet gear etc etc, the 225 could be considered as safe for flight (again), imho. Especially the more frequent scheduled MGB removals drive the costs per flight hours, but who cares.
However, after thousands of engineer hours and millions of Euros for the regarding technical investigation, the reason why a crack (twice) could propagate inside the gear rim, undetected by e. g. HUMS and the classical methods like mag plug and filter, remains still unknown. Strange, isn't it?
However, after thousands of engineer hours and millions of Euros for the regarding technical investigation, the reason why a crack (twice) could propagate inside the gear rim, undetected by e. g. HUMS and the classical methods like mag plug and filter, remains still unknown. Strange, isn't it?
AIRBUS HELICOPTERS FINDS ROOT CAUSE OF THE TUROY H225 CRASH | OGPNetwork
OGP NETWORK OIL GAS & POWER LATEST NEWS
AIRBUS HELICOPTERS FINDS ROOT CAUSE OF THE TUROY H225 CRASH
ByOGP Network
-
September 13, 2019 On April 29, 2016, one H225 Super Puma helicopter operated by CHC Helicopter, en route from Gulfaks B to Bergen, went down close to the small island of Turoy, west of Bergen, Norway. All 13 occupants of the heavy-twin, two pilots and eleven oilfield staff died within the accident after the primary rotor separated from the plane at 2,000ft. The lack of the primary rotor in flight is essentially the most dramatic accident that may occur to a helicopter. There are not any phrases to explain it.
The UK journal Flight Global reported that Airbus Helicopters has recognized the basis explanation for the primary gearbox (MGB) failure behind the deadly 2016 crash of an H225 in Norway. In its last report in July 2018, Norwegian investigators decided second-stage planet gear within the MGB’s epicyclic module had failed as a result of sub-surface cracking and fracture of a bearing race. However, they have been unable to say what had triggered the occasion.
“The investigation has proven that the mix of fabric properties, floor remedy, design, operational loading surroundings and particles gave rise to a failure mode which was not beforehand anticipated or assessed,” the report says.
But the airframer has continued its personal evaluation of the occasion, says H225 programme director Michel Macia, resulting in identification of the basis trigger and a profitable replication of the failure in testing. That work has been externally validated, he says. Findings from that effort have been subsequently shared with Norway’s SHT accident investigation physique, regulators together with the European Union Aviation Safety Agency, and different producers, says Macia.
“Everyone now is aware of that the basis trigger is known and has been reproduced,” says Macia. Although he declines to element the failure, he says the security obstacles put in place to allow the H225 to return to service take care of the underlying difficulty. These measures embrace a heightened inspection regime, shorter life limits on elements and – considerably – the exclusion of one of many two totally different bearing designs used on the helicopter.
The H225 and the associated AS332 L2 have been grounded for 4 months following the crash, and though each at the moment are cleared for service, they’ve but to be introduced again to operation within the North Sea area for offshore transport. While that’s largely as a result of overcapacity within the sector, there stays vital opposition from the oil and fuel workforce to the H225.
But Airbus Helicopters chief government Bruno Even nonetheless believes the rotorcraft could make a comeback within the North Sea and says the plane wants time to realize acceptance.
“We are doing all that we’re capable of do, however ultimately, it’s the buyer who has to determine.”
The UK Civil Aviation Authority says its place on the H225 has not modified and it has but to obtain an software from an operator to renew H225 passenger flights within the nation.
(Source: Flight Global – Image: Aibn/Super Puma rotor on Turoy Island)