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-   -   AW139 Crash in Bahamas - 7 Killed (https://www.pprune.org/rotorheads/623218-aw139-crash-bahamas-7-killed.html)

the coyote 26th Aug 2020 12:36

10 degrees nose down for 1 second on takeoff in the 139 is a standard profile and should be so rehearsed to be second nature, and definitely no big deal in the dark.

As professional pilots in custody of other peoples lives, if we aren't all over our power and attitude settings and the resulting aircraft performance during such a takeoff we simply shouldn't be out there doing it, or flying IMC.

To me and others I'm sure, the CVR transcript is horrifying from the start. Lack of command leadership, cockpit workload management and discipline, standard procedures or use of checklists, lack of basic familiarity with aircraft systems. If I was in the back listening to the pilots I would have been terrified.

A tragic human factors failure in a very capable machine that didn't fail them, and in fact tried its best to save them from themselves.

We bang on about respecting aircraft limits, but it is crucial that we set and respect personal limits. After many years flying HEMS single pilot IFR, there has been countless times not adhering to personal limits could have brought us unstuck. Ego's simply do not belong in the cockpit in my view.

[email protected] 26th Aug 2020 13:32


Since when is rotating 10 degrees nose down disorienting on an IFR departure in a helo?
when it is in the dark with no lighting except the landing lamp and you are not practised in the technique.

It is fine if you are on instruments as you rotate but if your IF ability is poor and you are trying to look outside instead of inside, there is every chance you will hit the ground/sea.

Ask anyone with experience of night deck departures from a ship where you go from some external references to none at all just as you transition.

wrench1 26th Aug 2020 15:00


Originally Posted by Twist & Shout (Post 10870643)
If someone was in the position to own and operate an AW139 for personal use, how would they ensure their pilots were up to the task? What could the owner have done to discover or rectify their total lack of proficiency?

In all honesty the owners don’t care or care to know. In my experience with owners of these types of operations, it is not a priority per se if their pilot/mechanic skill set is top notch but rather if they produce results when the owner wants them. The rest is secondary. Same goes with the mechanical condition of the aircraft in most cases. And unfortunately if said pilot, or mechanic/shop, does not perform to the owners satisfaction they will be let go as there is always someone else to step in.

It’s this same type of owner that if they had the desire/capabilities to fly would be making the same type flights and killing those close just like these pilots. Are there smart owners? Sure. But you never see them in the news as they maintain/operate their aircraft at a level we understand or use a fractional aircraft to achieve that same level.

And while most of us who work/worked in aviation day in and day out cannot fathom how any aircraft can be operated in such a manner, most of us usually worked under a veil rules, policies, and procedures that gave us a route to decline a flight or ground an aircraft. Whereas the career future of most pilots and mechanics that work for these fringe Part 91 private ops is based on a single yes or no.

So unless global regulatory authorities move to require a higher oversight of all Part 91 type ops, there will still be accidents like this without fail. And if you look at the data, money doesn’t have anything to do with it. It’s strictly a mindset.

ShyTorque 26th Aug 2020 17:21

There’s been a lot of discussion around takeoff profiles. It’s important to understand that the “performance” profiles are to mitigate the risk following a single engine failure, nothing else. Below TDP the idea is to land safely back on the departure point. If you lose sight of it as soon as you have lifted, due to insufficient lighting, there is little point in planning to carry out the performance profile. That is why there are rules and regulations appertaining to public transport flights regarding minimum pad size and minimum lighting (it appears that this was not such a flight).

Better in cases like this to concentrate on a safe transition from external cues to instruments and accept the possibly far lesser risk of an engine malfunction.

Whether this meets the legal requirements of public transport or not is another matter. In ideal circumstances a flight like this should have been flown from a properly laid out and lit helicopter landing site, but it appears that things had already gone beyond legality at the planning stage for other reasons. Irrespective of that, it could still have been safely flown.

Same again 26th Aug 2020 20:15

What he said. Thank you Shy Torque.

[email protected] 26th Aug 2020 21:12

Shy - :ok: and we are back to the IF take off - don't know why there is resistance to it's use.

Nescafe 27th Aug 2020 08:31

https://www-ainonline-com.cdn.amppro...ce-aw139-fatal

According to the NTSB, the AW139 crashed shortly after lifting off from a private helipad in the Bahamas shortly before 2 a.m. on a private medical evacuation flight to Fort Lauderdale, killing the pilots and five passengers. The NTSB’s performance study indicates that one minute and two seconds into the flight, the helicopter hit the water at a speed of 141 knots.







The study concludes: “While longitudinal input was not initially different from the prior 10 flights, the combination of high collective input and increasingly forward longitudinal cyclic inputs lead to significant nose-down attitudes during the flight that led to losses of altitude. A calculation of apparent pitch showed that it was possible for the pilots to have misinterpreted the helicopter’s nose-down attitude to be nose up for the entirety of the flight.”

Other documents contained in the docket, including the transcript from the cockpit voice recorder (CVR) and human factors report, fashion a mosaic of two pilots with marginal training performance, still unfamiliar with key systems of their aircraft, and a lack of crew resource management. The accident PIC was faulted for a basic lack of skills and knowledge during initial and recurrent training in 2017 and 2018. During 2018 recurrent training, “progressive training/checking was halted and changed to traditional 61.58 training due to the applicant not reaching the required proficiency and failed more items than required.”

Meanwhile, during the SIC’s initial training, instructors noted that he struggled with the FMS and had crew resource management “issues;” could be “overwhelmed” with weather, ATC, and flying; and did not always use a checklist, which led to “momentary loss of situational awareness during the flight.” Similar to the PIC’s 2018 recurrent training, the SIC’s training reverted to 61.58 due to failures. He also scored below average for Category A takeoffs and use of the flight director. His instructor noted, “The SIC was not trained or he received substandard initial training for all the maneuvers he failed.” Additional training led to a proficiency check pass.

Before the accident, the PIC and the SIC had flown together 14 times between November 2017 and February 2019. Ten of those flights were daylight, the other four could not be determined. On all flights, the PIC was always the pilot flying.

Twenty-three seconds before impact, the PIC appears to recognize and momentarily recover from pitch down attitude, acknowledging, "Yeah, we were diving," before reinitiating it. Fifteen seconds before impact, against the background of multiple electronic voice terrain warning alerts, the SIC remarked, “There was a fatal accident in the UK and this is exactly what happened there.”

If there was a recipe for disaster, it would start with ‘take 2 substandard pilots, add a complex machine, darkness and a high pressure tasking.’

Twist & Shout 27th Aug 2020 09:03

Nescafe

There are some sobering, salient, and frankly scary points in your post.

It’s the equivalent of employing a Limo driver who has lost his licence several times, and crashed a heap of cars in the last few years. Unbelievably.

nomorehelosforme 27th Aug 2020 10:45


Originally Posted by Twist & Shout (Post 10871593)
Nescafe

There are some sobering, salient, and frankly scary points in your post.

It’s the equivalent of employing a Limo driver who has lost his licence several times, and crashed a heap of cars in the last few years. Unbelievably.

It really does make grim reading to say the least, surely the pilots must have felt nervous about taking this flight with their experience...makes you wonder if they questioned the risks involved with themselves and or the owner prior to taking the flight or did they just bow to peer pressure to get on with the job?

Nescafe 27th Aug 2020 10:58


It really does make grim reading to say the least, surely the pilots must have felt nervous about taking this flight with their experience
You don’t know what you don’t know.

[email protected] 27th Aug 2020 11:00

Given their woeful training history and complete lack of basic CRM, they don't seem to have had the capacity to question why they were flying that night, let alone how they should best conduct the flight,

Very scary that pilots with such low standards are allowed to hold licences and fly pax.

How bad a pilot do you have to be to confuse nose up attitude with nose down? A 5 degree nose up attitude in a 139 is accelerative - no need to push the nose down further.

homonculus 27th Aug 2020 12:29

Cant fault these comments. My take is they were able to fly daytime VFR to an extent that they survived. Now take an unexpected nighttime flight, illegality, plus sudden illness and a need to 'save a life' and the boss demanding it, and you have a set of circumstances that would stretch or degrade many competent pilots. Degrade pilots that demonstrate no CRM and are already marginal either in terms of PIC or as a crew and it becomes dangerous.

Once again it may be a failure to say no. A failure to resist the employer or commercial pressure. It happened with Michael Harding with a pilot leagues above this PIC in terms of capability and competence, and it is very hard to prevent it happening again.

FH1100 Pilot 27th Aug 2020 13:46

Okay, they screwed up and crashed and killed everybody. After the fact, we look for the "why" of it.

Best description that I've read of this accident: Two single-pilots flying a machine by themselves together that neither were familiar with nor comfortable in. At night. Over water. Under pressure.

We tend to assume that the guys flying the S-76's and AW139's and such are the "best of the best"...the most highly-trained (and paid!)...the most disciplined...why, the very cream of the crop of the rest of us R-44 goobers. Then we read a CVR transcript like the one from this accident and go, "Yikes! Them guys were two goobers just like me!" Makes you wonder, doesn't it?

What struck me was this: As the passengers were boarding, I expected that the two of them would engage in *some* sort of takeoff briefing. Something. Like, maybe one of them would verbalize what he was about to do so the other one would know what to expect. But no. All of a sudden, I'm reading and I understand that they'd already taken-off! Seemed to me like they both got Spatial-D pretty quick. The guy on the controls obviously had it, but the PNF probably had it too. Otherwise, as it was all going to hell (pear-shaped?) he should've said, "Okay, *I'VE* got the controls!" and then saved the day...night.

Very sad. I don't know that I'll ever look at corporate pilots the same way again.

Viper 7 27th Aug 2020 15:17


Originally Posted by [email protected] (Post 10871057)
when it is in the dark with no lighting except the landing lamp and you are not practised in the technique.

It is fine if you are on instruments as you rotate but if your IF ability is poor and you are trying to look outside instead of inside, there is every chance you will hit the ground/sea.

Ask anyone with experience of night deck departures from a ship where you go from some external references to none at all just as you transition.

5 years RCAF Sea King at sea and 15 years of SAR here.

Been there, etc.


Viper 7 27th Aug 2020 15:22


Originally Posted by [email protected] (Post 10871310)
Shy - :ok: and we are back to the IF take off - don't know why there is resistance to it's use.

Yup. ITO is simple and works extremely well in the dark, IMC and other degraded visual environments like sand/snow etc.

vaibronco 27th Aug 2020 19:40

In august 2016, after the G-LBAL accident I wrote this message to AAIB web-team.
I never got an answer.

"I disagree with:



1) “a slight tailwind may have affected the

helicopter during its departure; this would be one cause of a late registering of airspeed

in comparison with other, into-wind, departures”



In my experience, late registering of airspeed happens in all confined/vertical/short-field procedures, with front wind, and with a maximum 10° nose down pitch as indicated by the RFM.

Attitude recovering from -10° to 0° is commanded by time (2 seconds) and not by airspeed, ground speed or outside visual references.

The manual dictates then that the 0° pitch must be maintained till Vtoss is reached.

Several seconds with 0° pitch are necessary before suddenly airspeed gets “alive” and goes, in a very short time and sometimes instantly, from zero to 40/50Kts IAS.

During night VFR departures from coastal helipads, visual references are actually lost at TDP.

Take-off procedure is then performed from TDP with the sole reference to instruments till modes can be engaged (Phase 5 software) only at 60Kts IAS.

Experience in these procedures during day VFR operations integrates the type rating training, giving the pilot the absolute trust in the effectiveness of the sequences, even during the zero kts IAS phase.

Moreover, cues for pitch and power index are available (when set) in the PFD during all the sequence from hover to Vtoss, no matter if day or night operations.

Therefore, Cat A take-off procedures are actually performed with reference to instruments even during day VFR operations.

RFM and TRI should emphasize that

- Category A take-off procedures are actually performed with reference to instruments even during day VFR operations

- Delay in IAS is usual in these procedures and should be ignored till it gets “alive”



In my opinion, to be discussed:



“Safety Recommendation 2015-025

The European Aviation Safety Agency should amend its definition of Vmini, to

provide a clear definition that reflects the legitimacy of flight under instrument

flight rules by reference to external visual cues at speeds below Vmini.”

As per AW139 RFM, external cues are not utilized after TDP to perform a correct Cat A vertical/confined/short-field take-off."
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



funfinn2000 28th Aug 2020 08:17


Originally Posted by Nescafe (Post 10869625)
It’s very sad to reflect that if they had simply pressed the CAT A button they could have just followed the guide bars to safely depart and climb away. The fact that they didn’t know where the landing light was would indicate that they probably didn’t even know about the function that would have saved their lives.


This aircraft didnt have that phase of software.

212man 28th Aug 2020 08:55


Therefore, Cat A take-off procedures are actually performed with reference to instruments even during day VFR operations.

RFM and TRI should emphasize that

- Category A take-off procedures are actually performed with reference to instruments even during day VFR operations
I have not flown the AW139 (except as pax) but have flown a number of types with vertical Cat A procedures, including types that have a nose high hover attitude, and I would disagree with your assertion. Being able to set pitch attitude by external reference is such a basic concept, that (should) be inculcated into a student pilot from their very first lessons, that does not change once you operate a larger more sophisticated aircraft. I am reminded of line training brand new ab-initio co-pilots, who would fixate on the PFD/ADI during take off - particularly offshore. On one occasion I asked the individual how long they thought they had been 'eyes in' during a rig departure - they thought a couple of seconds, whereas it was actually 13. I would often cover the PFD with the checklist to enforce the habit of looking at the' real horizon' rather than the 'artificial horizon'!

At night or DVE with no discernable horizon or references it is a totally different case, and I absolutely advocate reference to the instruments during this critical phase of flight, and it would/should have been the difference between a successful departure versus what actually happened in this accident flight (and many others).

[email protected] 28th Aug 2020 12:04

But in order to fly a vertical helipad departure on instruments, you would have to sit left wing low and nose up (hover attitude) and maintain that until TDP (or you won't go vertical) - that is an IF take off in all but name.

sycamore 28th Aug 2020 12:15

For those interested if you read Document #22,P5,FIG 3 ,YAW PEDAL input,then go to P17,,paragraph starts"Figure13 shows......",and read the interpretation of the NTSB Performance specialist......

212man 28th Aug 2020 12:51


Originally Posted by [email protected] (Post 10872638)
But in order to fly a vertical helipad departure on instruments, you would have to sit left wing low and nose up (hover attitude) and maintain that until TDP (or you won't go vertical) - that is an IF take off in all but name.

Not sure if that's aimed at me? I fully agree - I just disagree that all 139 (or any type) vertical profiles should be done on instruments in day VFR.

[email protected] 28th Aug 2020 14:37


I just disagree that all 139 (or any type) vertical profiles should be done on instruments in day VFR
Agreed :ok:

ApolloHeli 28th Aug 2020 14:42


Originally Posted by sycamore (Post 10872652)
For those interested if you read Document #22,P5,FIG 3 ,YAW PEDAL input,then go to P17,,paragraph starts"Figure13 shows......",and read the interpretation of the NTSB Performance specialist......

Missed that the first time - Isn't the AW139 rotor system anti-clockwise? So surely power pedal is left pedal?

[email protected] 28th Aug 2020 14:59


For those interested if you read Document #22,P5,FIG 3 ,YAW PEDAL input,then go to P17,,paragraph starts"Figure13 shows......",and read the interpretation of the NTSB Performance specialist......
so either the specialist doesn't know which way round the rotor turns or has got his lefts and rights mixed up.

ApolloHeli 28th Aug 2020 16:04


Originally Posted by [email protected] (Post 10872774)
so either the specialist doesn't know which way round the rotor turns or has got his lefts and rights mixed up.

It would appear the labelling on the charts suggest right pedal was applied, so it's not a just the one typo, which is odd. Maybe they just read the FDR data backwards, but still not a mistake I'd expect to find in an NTSB report.

Arcal76 31st Aug 2020 23:27

What Vaibronco said is right !
We do all our vertical take-off, it does not matter how high you have to climb, the same way, day or night.
If you do that all time, you just know what you gone see and what the aircraft is doing. 10 degrees nose down 1 second, level off, you know that the airspeed won't show up until you reach 40, with VTOSS, 5 degrees nose up to reach Vy.
We don't have to guess what to do, it is always the same. Now, at night, it is crucial to follow your instrument, there is no other way. We only have NVG's for a 1 1/2 year, I flew 20 years without NVG's doing the same thing with all kind of weather and sites.
Is it easy ? no, it is not and sometimes you really have to concentrate and make sure the guy beside you makes the right calls and check you. The only thing the NVG brings on black hole is to see your reject area, when you rotate, you only look and follow your instruments.
Now, if you never do those profile and try to do it on a black hole, that's a different story, that's gone be difficult to go from 7 degrees nose up to -10 and you will have many risk of being disoriented.
They could have use the Transition up, but I am sure they never even it tried before, you can only do it on a flat surface, from hover, It is a little bit strange because the aircraft vibrate, move slowly initially until you reach enough speed to stabilize everything, departing above water using TU can look scary.
At the end of the day, it is very difficult to say and accept that you are not good enough or not trained enough to do a job, especially on VIP jobs. The only guys who could tell you is your partner (if he understand the situation) and the training guys.
But, it is another problem, we go to CAE and now flight Safety. Who is gone say, " We think you don't have the right level for the job you do". Nobody !!! Most of them don't even understand what we do. " Ho you Canadians, you do all those black hole profiles, it is crazy".Yes, it is but, it is part of the job and we tried over those years to improve those profiles to make them better. Now, with NVG's, we don't have problem to go anywhere as before, but the take-off is still something to manage properly.
All guys who did their training knew what problems those guys had and they should have react. Even you can't know what a customer is gone do with his aircraft, the minimum should focused on aircraft knowledge and management. They should leave the sim with a perfect knowledge of FMS, automation and crew management. Using automation without a perfect knowledge of is happening is a killer, the confusion you get is the best way to have a major mishap.

gulliBell 1st Sep 2020 01:25


Originally Posted by Arcal76 (Post 10875573)
...They should leave the sim with a perfect knowledge of FMS, automation and crew management..

They should arrive at the sim with a perfect knowledge, etc. The number of hours I've wasted teaching recurrent pilots in sims the basic stuff of what button to push and when, of systems knowledge, etc The sim is for honing technique, achieving finesse, doing stuff that you can't do in the real aircraft without risk of breaking it. It is not for teaching the basics.

Nescafe 1st Sep 2020 02:37


Originally Posted by gulliBell (Post 10875614)
They should arrive at the sim with a perfect knowledge, etc. The number of hours I've wasted teaching recurrent pilots in sims the basic stuff of what button to push and when, of systems knowledge, etc The sim is for honing technique, achieving finesse, doing stuff that you can't do in the real aircraft without risk of breaking it. It is not for teaching the basics.

There’s nothing like spending time in a sim that costs $1000s per hour, teaching someone something that ought to have been mastered in the aircraft in the hangar on external power.

212man 2nd Sep 2020 08:37


What Vaibronco said is right !
We do all our vertical take-off, it does not matter how high you have to climb, the same way, day or night.
If you do that all time, you just know what you gone see and what the aircraft is doing. 10 degrees nose down 1 second, level off, you know that the airspeed won't show up until you reach 40, with VTOSS, 5 degrees nose up to reach Vy.
We don't have to guess what to do, it is always the same.
I never said "guess" or use different profiles, I said use the visual references in daytime (when they exist) and use instruments at night, or in degraded day visual conditions. Are you saying you can't set 10 degrees nose down, or zero pitch by looking out the window?


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