AAIB Bulletin: Morecambe Bay
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Goonsuits?
Do the CHC aircrew suits have a full neckseal? Many years ago I suffered subtle incapacitation from a new and overtight neck seal and nearly blacked out on finals to a ship at night - fortunately had a co-pilot to hand over to.
Gyro failures that can bite you.....what kind of gyro failure affects all three attitude indicators?
The standby should have an independent power source so that it remains operable even under a complete electrical failure (loss of both/all generators/inverters) should it not?
I always thought step one in an unusual attitude indication or upset....is to poll the jury and go with the two AI's that agree and ignore the odd man out. Or am I getting senile here.
The standby should have an independent power source so that it remains operable even under a complete electrical failure (loss of both/all generators/inverters) should it not?
I always thought step one in an unusual attitude indication or upset....is to poll the jury and go with the two AI's that agree and ignore the odd man out. Or am I getting senile here.
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The way the report reads both pilots appear to have had a go in correcting what started as a pretty outrageous UP (38 degrees nose down & 38 degrees AOB) which would infer that each was flying by reference to his own independat flight instruments.
In addition the lack of any CVR evidence to suggest any other factors in play and the final report statement that the aicraft from FDR/CVR data appeared to behave in response to control inputs paints a fairy strong argument for disorientation and failure to recover fully from the UP. The question remians - WHY?
I do this thing every day and I cannot imagine how the AC was able to achieve such an extreme UP during a go-around when both pilots should be concentrating or at least alert enough for the NHP to intervene as the UP developed. I am also concerned that the initial report from AAIB does not explain how quickly the original UP developed and therefore how much time the NHP had to react.
Also I cannot imagine what took place that would lead the co-pilot to effectively "give-up" and ask for help. In my experience when the suituation is thus (ie in the simulator) the HP is so overaroused there is no brain power left to ask and the NHP intervenes naturally.
Finnally the Commanders failure to correct the UP fully in the time frame the report suggests does not feel right either.
The report does a really good job at inferring that these two experienced well trained flight crew loss control and flew into the sea. I am really struggling to accept that to be the case.
In the offshore industry, airspeed is probably the number one referenced instrument during approaches offshore due to the performance issues we operate under. During a go-around it is also watched carefully by both HP and NHP. The report provides FDR evidence of very high airspeeds throughout the UP and very high RODs. Both of these parameters whould lead to a powerful desire by both pilots to pull up the nose and yet the opposite happened in both cases.
In addition the initial approach was poorly handled by the co-pilot despite the fact that these crews are in engaged in a very high number of approaches and landings in the shuttle sector.
If I were a betting man I would look closely at the pitot-static system!!!!
In addition the lack of any CVR evidence to suggest any other factors in play and the final report statement that the aicraft from FDR/CVR data appeared to behave in response to control inputs paints a fairy strong argument for disorientation and failure to recover fully from the UP. The question remians - WHY?
I do this thing every day and I cannot imagine how the AC was able to achieve such an extreme UP during a go-around when both pilots should be concentrating or at least alert enough for the NHP to intervene as the UP developed. I am also concerned that the initial report from AAIB does not explain how quickly the original UP developed and therefore how much time the NHP had to react.
Also I cannot imagine what took place that would lead the co-pilot to effectively "give-up" and ask for help. In my experience when the suituation is thus (ie in the simulator) the HP is so overaroused there is no brain power left to ask and the NHP intervenes naturally.
Finnally the Commanders failure to correct the UP fully in the time frame the report suggests does not feel right either.
The report does a really good job at inferring that these two experienced well trained flight crew loss control and flew into the sea. I am really struggling to accept that to be the case.
In the offshore industry, airspeed is probably the number one referenced instrument during approaches offshore due to the performance issues we operate under. During a go-around it is also watched carefully by both HP and NHP. The report provides FDR evidence of very high airspeeds throughout the UP and very high RODs. Both of these parameters whould lead to a powerful desire by both pilots to pull up the nose and yet the opposite happened in both cases.
In addition the initial approach was poorly handled by the co-pilot despite the fact that these crews are in engaged in a very high number of approaches and landings in the shuttle sector.
If I were a betting man I would look closely at the pitot-static system!!!!
Combine Operations
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One of my constant concerns when approaching a platform was that for quite some time in the final stages, the PNF (Pilot Not Flying) has no visual contact with the helideck, because it is obscured by the instrument panel. The aircraft heading is offset by the PF so that he can have a better view of the deck. Depending on the size and layout of the platform, that might also be out of the PNF's view.
On a dark and stormy night he might have no external visual clues whatever in those latter stages of the approach - no moon, no horizon, an empty sea.
If the PF is late in realising he ought to go around or hand over control, or suffer subtle incapacitation, then it might be extremely difficult for the PNF to appreciate the gravity of the situation until it is too late.
Question: if there was a gyro fault such that, for example, there was a cockpit indication of a 38 degree AOB while the wings were level, what would the FDR indicate - level flight or 38 degrees AOB? The pitot-static system indications would surely be the same in the cockpit and the FDR? In the bulletin, there is nothing that suggests to me there was a fault there.
We obviously have to wait for the CVR data to be published. I know regular passengers were most concerned about the possibility of mechanical failure. Personally, I do not know what to wish for.
On a dark and stormy night he might have no external visual clues whatever in those latter stages of the approach - no moon, no horizon, an empty sea.
If the PF is late in realising he ought to go around or hand over control, or suffer subtle incapacitation, then it might be extremely difficult for the PNF to appreciate the gravity of the situation until it is too late.
Question: if there was a gyro fault such that, for example, there was a cockpit indication of a 38 degree AOB while the wings were level, what would the FDR indicate - level flight or 38 degrees AOB? The pitot-static system indications would surely be the same in the cockpit and the FDR? In the bulletin, there is nothing that suggests to me there was a fault there.
We obviously have to wait for the CVR data to be published. I know regular passengers were most concerned about the possibility of mechanical failure. Personally, I do not know what to wish for.
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To my knowledge, the info on pitch and roll comes from the copilots ADI, then fed in parallel to the IHUMS and FDR. There are 3 ADI's on the Dauphin.
Someone mentioned pitot static input. Remember that a trimble GPS is fitted, where groundspeed can be monitored and there are two independent pitot systems.
I can't see how a pitch and bank of 38 degrees can be put to a problem with air data instruments.
The data which is fed to the FDR is calibrated every 12 months.
Someone mentioned pitot static input. Remember that a trimble GPS is fitted, where groundspeed can be monitored and there are two independent pitot systems.
I can't see how a pitch and bank of 38 degrees can be put to a problem with air data instruments.
The data which is fed to the FDR is calibrated every 12 months.
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They still remained water tight. I used my suit for the dunker training which kept me dry.
They are also black which makes you very difficult to find in the water at night!
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The immersion suits used are Blue with reflective tapes on the legs.
If you have survived a ditching and inflated the lifejacket, the firefly strobe and sea light will aid any rescuer as well as the tapes on the Day-Glo orange jacket.
If you have survived a ditching and inflated the lifejacket, the firefly strobe and sea light will aid any rescuer as well as the tapes on the Day-Glo orange jacket.
Divergent - blue looks like black in the water in anything other than bright sunlight and if you don't inflate your lifejacket (incapacitated) you are therefore invisible (unless you can float with your legs in the air). People in orange/red suits are easy to see.
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Good to see from Double Bogey's last post some real effort to try and understand what was going on in the last moments of the flight and consider why. It is important to appreciate that this process is not about seeking to blame anyone but enable those of us that care, to focus on what could have gone wrong and where we might make even greater efforts to avoid errors - and that could refer to pilots, engineers and aircraft manufacturers. Doing so could well prevent more accidents during the time it takes for a full detailed report to be published.
I agree with Double Bogey, this does seem odd. Although not an offshore pilot, I too am baffled at just how such a big unusual attitude - especially 38 deg nose down - could occur with two experienced IR pilots.
The comment that "the crew became unhappy with the approach" etc is significant. It would be interesting to know exactly what was said on the CVR to know this. Presumably the PF Co-pilot was unhappy about something, but what exactly? How unusual is it for a missed approach and go-around to a rig to occur from a VFR approach? And when they do - let's say here because of poor visual reference in poor vis, what is the procedure? Clearly at this stage the flight is VFR, but is the policy to immediately fly by reference to instruments, or is to try and regain visual reference? If it was the former, it is harder to understand how such a big attitude change could occur - let's face it, 38 deg down looks pretty obvious and dramatic on the AI, and the starting point from a controlled approach and early go-around attitude would be a fairly normal AI picture. But if eyes were out of the cockpit believing adequate visual reference existed - maybe wrongly - I guess 38 deg down could well arise.
Whatever the level of concentration of the PNF on the approach - and clearly it should be high - one would assume it would be even higher as soon as the PF says he's unhappy and going around, with full orientation on all references - outside and instruments.
Next, after the go-around is commenced, the PF is concerned enough to ask for assistance. Is that unusual? I would have thought so, assuming he's not feeling unwell. Anyway now our hopefully orientated formerly PNF commander takes over - and within a second the aircraft is 38 deg nose down and 38 deg banked right. Another 3 seconds later it's level but still 13 deg nose down, and over the next 5 seconds presumably little more control input happens until it hits the sea. Doesn't sound like someone grappling to establish a sensible attitude on the AI.
Seems all a bit odd to me, I must say. I look forward to reading the full report especially info relating to the instruments, but there again it had a full dual panel and two pilots couldn't sort it out.
I agree with Double Bogey, this does seem odd. Although not an offshore pilot, I too am baffled at just how such a big unusual attitude - especially 38 deg nose down - could occur with two experienced IR pilots.
The comment that "the crew became unhappy with the approach" etc is significant. It would be interesting to know exactly what was said on the CVR to know this. Presumably the PF Co-pilot was unhappy about something, but what exactly? How unusual is it for a missed approach and go-around to a rig to occur from a VFR approach? And when they do - let's say here because of poor visual reference in poor vis, what is the procedure? Clearly at this stage the flight is VFR, but is the policy to immediately fly by reference to instruments, or is to try and regain visual reference? If it was the former, it is harder to understand how such a big attitude change could occur - let's face it, 38 deg down looks pretty obvious and dramatic on the AI, and the starting point from a controlled approach and early go-around attitude would be a fairly normal AI picture. But if eyes were out of the cockpit believing adequate visual reference existed - maybe wrongly - I guess 38 deg down could well arise.
Whatever the level of concentration of the PNF on the approach - and clearly it should be high - one would assume it would be even higher as soon as the PF says he's unhappy and going around, with full orientation on all references - outside and instruments.
Next, after the go-around is commenced, the PF is concerned enough to ask for assistance. Is that unusual? I would have thought so, assuming he's not feeling unwell. Anyway now our hopefully orientated formerly PNF commander takes over - and within a second the aircraft is 38 deg nose down and 38 deg banked right. Another 3 seconds later it's level but still 13 deg nose down, and over the next 5 seconds presumably little more control input happens until it hits the sea. Doesn't sound like someone grappling to establish a sensible attitude on the AI.
Seems all a bit odd to me, I must say. I look forward to reading the full report especially info relating to the instruments, but there again it had a full dual panel and two pilots couldn't sort it out.
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When approaching a rig in night VMC the final approach provides plenty of visual cues to a reasonably experienced offshore pilot. Normally this terminates in a safe landing and for some pilots this will be the case for majority of their careers (when vmc). However, a go-around from a platform in VMC, where the immediate go-around area has no other lit objects to provide visual clues, or worse, an array of confusing objects at distance, it is very very easy to become disorientated and things happen quickly thereafter.
To my knowledge there have been at least 2 AC touchdowns into the water that have survived by rapidly apply pitch both attributable to disorientation in reasonable VMC but possibly confusing visual cues out of the windows.
Most offshore pilots who are regularly engaged in IFR operations, rig radar approaches etc, would normally immediatley convert to instruments should a go-around occur, vmc or otherwise as the dangers of not doing so are ussually experienced in the safety of a flight simulator. This critical conversion is not easy and requires the pilot to be skilled and practised and fully comfortable with what the instruments are telling him. At such a satge in flight the seat of the pants is as much use as a chocolate fireguard!
If it is proven beyond reasonable doubt that this was a disorientation followed by a failure to recover to controlled climbing flight then my deep conviction is that such events become less likely if both crews have experienced the event in the simulator beforehand and recieve regular recurrent training in the sim to re-inforce these critical periods of flight.
Without simulator training some offshore pilots may NEVER EVER experience a go-around in night VMC where they are required to establish quickly on the panel.
It has happended to me twice and both events left me feeling less secure in my own abilities to complete this manouvre with the ease that I would normally expect from myself. It is a VERY demanding manouvre and I have been a regular sim visitor for the past 10 years.
A go-around form a rig radar is very different from a VMC event as the HP remains handling and is on instruments throughout the procedure.
This unfortunate event and it resulting tragedy may finally be what it will take for the Authorities to mandate sim training for all offshore flight crews and give us all a reasonable chance of practising these critical flight conditions so that safety is assurred when the unexpected happens.
You can bet you bottom $ that the Authorities read these pages so lets hear from anyone else who has struggled with a Night VMC approach and go-around!! I strongly suspect there are a lot of us out there!!
To my knowledge there have been at least 2 AC touchdowns into the water that have survived by rapidly apply pitch both attributable to disorientation in reasonable VMC but possibly confusing visual cues out of the windows.
Most offshore pilots who are regularly engaged in IFR operations, rig radar approaches etc, would normally immediatley convert to instruments should a go-around occur, vmc or otherwise as the dangers of not doing so are ussually experienced in the safety of a flight simulator. This critical conversion is not easy and requires the pilot to be skilled and practised and fully comfortable with what the instruments are telling him. At such a satge in flight the seat of the pants is as much use as a chocolate fireguard!
If it is proven beyond reasonable doubt that this was a disorientation followed by a failure to recover to controlled climbing flight then my deep conviction is that such events become less likely if both crews have experienced the event in the simulator beforehand and recieve regular recurrent training in the sim to re-inforce these critical periods of flight.
Without simulator training some offshore pilots may NEVER EVER experience a go-around in night VMC where they are required to establish quickly on the panel.
It has happended to me twice and both events left me feeling less secure in my own abilities to complete this manouvre with the ease that I would normally expect from myself. It is a VERY demanding manouvre and I have been a regular sim visitor for the past 10 years.
A go-around form a rig radar is very different from a VMC event as the HP remains handling and is on instruments throughout the procedure.
This unfortunate event and it resulting tragedy may finally be what it will take for the Authorities to mandate sim training for all offshore flight crews and give us all a reasonable chance of practising these critical flight conditions so that safety is assurred when the unexpected happens.
You can bet you bottom $ that the Authorities read these pages so lets hear from anyone else who has struggled with a Night VMC approach and go-around!! I strongly suspect there are a lot of us out there!!
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Not that I'm suggesting we rely completely on autopilots, but the newer generation aircraft have a go-around facility at the press of a button. With heading engaged and go-around pressed it makes the change from visual to instrument a lot more comfortable. Those that have flown glass with 4 axis, generally never want to go back.
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Very interesting response Double Bogey from someone who obviously knows this environment. It is clear night rig approaches in VMC can transform from being relatively straightforward with good visual reference with the platform on approach to being really tricky on a go-around when the lights are gone and it's just inky blackness - and at low level. Hard to think how this should not automatically require an instant transition to instruments.
I too have had my most anxious moments in the potentially fluctuating transition phase from IMC to VMC flight when flying SPIFR on an approach. Letting down on instruments on a wet misty night can be reasonably straightforward until you become visual. At that point you are really reliant on continued vision of ground lighting and if that disappears - either because you've passed over what you were looking at or denser rain or mist is hindering visibility, it can get very difficult and all you can do is pull back up, get back on the instruments and rapidly climb to safe altitude and plan again. There is the added danger that if speed reduces with a flare on initially becoming visual, if that visual reference is lost the airspeed may be dropping below minimum IMC speed, especially with a rapid cyclic pull back to maintain obstacle clearance on reverting to instruments.
Is there a policy on night rig approaches even in VMC of the PNF following through solely on instruments, so that if the PF calls go-around the PNF can smoothly and calmly take over, already fully orientated on the instruments? Assuming Radalt monitoring in the scan, this would have the added benefit of safeguarding against disorientation on the approach.
I too have had my most anxious moments in the potentially fluctuating transition phase from IMC to VMC flight when flying SPIFR on an approach. Letting down on instruments on a wet misty night can be reasonably straightforward until you become visual. At that point you are really reliant on continued vision of ground lighting and if that disappears - either because you've passed over what you were looking at or denser rain or mist is hindering visibility, it can get very difficult and all you can do is pull back up, get back on the instruments and rapidly climb to safe altitude and plan again. There is the added danger that if speed reduces with a flare on initially becoming visual, if that visual reference is lost the airspeed may be dropping below minimum IMC speed, especially with a rapid cyclic pull back to maintain obstacle clearance on reverting to instruments.
Is there a policy on night rig approaches even in VMC of the PNF following through solely on instruments, so that if the PF calls go-around the PNF can smoothly and calmly take over, already fully orientated on the instruments? Assuming Radalt monitoring in the scan, this would have the added benefit of safeguarding against disorientation on the approach.
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There seems to be a trend in this thread to conclude that this accident was caused by dis-orientation. This may, after a full enquiry, be the case but there are still many unanswered questions.
The weather was fit for night shuttling with a useful 20+kts of wind to lean into. The crew had completed at least one night landing before the accident so were in the groove of night approaches. The crews at Blackpool regularly do several approaches each night so are well practised in low-level ops over the sea. The a/c was light with only 5 pax (10 can be carried) so performance wasn't an issue.
So what caused the experienced current co-pilot to roll away from the rig, accelerate and increase power, then increase the roll while pitching nose down then ask for assistance? This doesn't sound like classic disorientation, as he would have had the deck in site for most of the initial manoeuvre. Something else must have distracted the crew or caused the initial roll/pitchdown. Let us wait and see what the AIB final report says.
As a matter of accuracy for previous posts:-
Cyclic - the Dauphine has a go round button, which sets 75kts so long as the coupler is engaged - not likely during an approach.
Doublebogey - you are looking at this accident from, I believe, a Puma viewpoint. We spend most of our time with the height and heading hold engaged and it is unusual for us to do more that 20 night rig approaches a yr. A Blackpool Dauphin crew will do that in 2 days during the winter and go rounds are not unusual as during a shuttle it is not unrealistic to have to do at least one overshoot due to a deck crew not being ready. The transition from visual with a rig to the big black hole is an every night occurrence.
SteveMc - The Dauphin autopilot has 2 lanes one fed from the captain's and the other from the co-pilot's AI and compass. A discrepancy in info causes that channel to drop out with an A/P red alarm. The Trimble GPS ground speed function would be a hindrance in this sort of scenario as it is difficult to see and well away from the normal instrument scan.
Rotorspeed - yes the PNF has a responsibility to monitor the approach, call 55kts and acknowledge the commited (to land) call. This accident was not at the end of a rig radar approach so your comments about becoming visual do not apply
Let us wait for the full report before trying to come to a firm conclusion.
332M
The weather was fit for night shuttling with a useful 20+kts of wind to lean into. The crew had completed at least one night landing before the accident so were in the groove of night approaches. The crews at Blackpool regularly do several approaches each night so are well practised in low-level ops over the sea. The a/c was light with only 5 pax (10 can be carried) so performance wasn't an issue.
So what caused the experienced current co-pilot to roll away from the rig, accelerate and increase power, then increase the roll while pitching nose down then ask for assistance? This doesn't sound like classic disorientation, as he would have had the deck in site for most of the initial manoeuvre. Something else must have distracted the crew or caused the initial roll/pitchdown. Let us wait and see what the AIB final report says.
As a matter of accuracy for previous posts:-
Cyclic - the Dauphine has a go round button, which sets 75kts so long as the coupler is engaged - not likely during an approach.
Doublebogey - you are looking at this accident from, I believe, a Puma viewpoint. We spend most of our time with the height and heading hold engaged and it is unusual for us to do more that 20 night rig approaches a yr. A Blackpool Dauphin crew will do that in 2 days during the winter and go rounds are not unusual as during a shuttle it is not unrealistic to have to do at least one overshoot due to a deck crew not being ready. The transition from visual with a rig to the big black hole is an every night occurrence.
SteveMc - The Dauphin autopilot has 2 lanes one fed from the captain's and the other from the co-pilot's AI and compass. A discrepancy in info causes that channel to drop out with an A/P red alarm. The Trimble GPS ground speed function would be a hindrance in this sort of scenario as it is difficult to see and well away from the normal instrument scan.
Rotorspeed - yes the PNF has a responsibility to monitor the approach, call 55kts and acknowledge the commited (to land) call. This accident was not at the end of a rig radar approach so your comments about becoming visual do not apply
Let us wait for the full report before trying to come to a firm conclusion.
332M
I have the feeling that this go-around function can be a little bit sluggish to recover an unusual postion at such a low height, with relatively high pitch and bank angle. It brings your "wings" level and looks for Vy but in a rather smooth manner....
There are so many thinks or combinations of factors that could have happened, once again, only the full investigation will tell.
There are so many thinks or combinations of factors that could have happened, once again, only the full investigation will tell.
I'll have to plead complete ignorance about a 365N autopilot system, but I find this tangent on "Go Around" as muddled and uncertain as that other red herring - the AVAD.
So let me put it out to all of you on the "Go Around" function and offshore approaches. Honestly, I didn't think anyone used it anymore for anything except perhaps an ILS. There are far more useful modes to couple to and stay coupled with. "Go Around" is for when you've gone brain-dead and can't think of anything else except not going any closer to the ground.
malabo
So let me put it out to all of you on the "Go Around" function and offshore approaches. Honestly, I didn't think anyone used it anymore for anything except perhaps an ILS. There are far more useful modes to couple to and stay coupled with. "Go Around" is for when you've gone brain-dead and can't think of anything else except not going any closer to the ground.
malabo