Police helicopter crashes onto Glasgow pub
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yes, why was this task extended? and why is it so quiet now from the police, the customer? they were on a observation task, non urgent - at that time..
perhaps something was developing, not untypical on a Friday night, and the crew wanted to go back to base, refuel and get airborne asap again. Or the next crew was waiting to take over? Old instincts to get back to base, or as close as possible? Bear in mind he was convinced he had enough fuel to get home - and indeed, he had. But not the engines. Could it be some medical issues affected the pilots performance, something he was maybe not at all aware off and caught by surprise during flight - so in such a case perhaps he felt not comfortable to land in a field or city at night and the decision to return to base was simply HIS best option at the time? who knows.
perhaps something was developing, not untypical on a Friday night, and the crew wanted to go back to base, refuel and get airborne asap again. Or the next crew was waiting to take over? Old instincts to get back to base, or as close as possible? Bear in mind he was convinced he had enough fuel to get home - and indeed, he had. But not the engines. Could it be some medical issues affected the pilots performance, something he was maybe not at all aware off and caught by surprise during flight - so in such a case perhaps he felt not comfortable to land in a field or city at night and the decision to return to base was simply HIS best option at the time? who knows.
But he had been off on extended leave recently. So how current was he? How long since converting from the Chinook? At moments of extreem pressure does one revert to the more familiar?
How would One ever be able to confuse a Chinook cockpit with a 135 Cockpit and completely confuse One's Self about the Fuel Systems?
Jesus Wept....and all the Disciples Chanted.....give it a break will you?
Chief Bottle Washer
It's obviously time for yet another reminder to refrain from going over issues that have been asked and answered, sometimes more than once.
It may be a long thread but the professional pilots here are quite justified in getting short with those who either too lazy or too selfish to be aware of the details that have been patiently explained, often in very specific detail.
Any posts that go over old ground will disappear without explanation, as will any dealing with alien abductions.
It may be a long thread but the professional pilots here are quite justified in getting short with those who either too lazy or too selfish to be aware of the details that have been patiently explained, often in very specific detail.
Any posts that go over old ground will disappear without explanation, as will any dealing with alien abductions.
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BLADECRACK - I about 2k emergency hours on 355 and 105. Both types require careful fuel management when the fuel states get close to the MLAs.
In this case there was plenty of fuel in the main tank. It remained there because the pilot did not switch the transfer pumps back on. As a consequence the LOW FUEL warning illuminated (recorded by the VMS) and the RFM requires a landing within 10 mins. To an experienced pilot this means land ASAP. These two facts are the most significant in the report.
I wonder how many times this situation had arisen where the outcome was favourable.
What you, and many others on this thread fail to appreciate is that in attempting to discredit the fuel contents and indicating system you are actually promoting a culture where indications are no longer relied upon are indeed acted upon.
As such, two habits form. 1. Lack of trust and therefore conservative application of limits OR 2. lack of trust leading to a belief that there is probably more fuel available than indicated.
This aircraft, based on the total contents indicated AND the pilots in flight airmanship was already below the MLA in the OM and he had still not reached his landing site. To me this indicates a habit based on condition 2 above. Complacency leading to mismanagement of the fuel system.
It is remarkable simple if you think about it. With less than 100 kgs in the main tanks at least one or both TRFR pumps needed to be on. I would think that is an obvious requirement regardless of the perceived pressures of the task.
Fuel system indications are a lot more robust that posters on this thread like to intimate. As such, if the LOW FUEL lights illuminate in flight.....hers my to tip. LAND ASAP.
DB
In this case there was plenty of fuel in the main tank. It remained there because the pilot did not switch the transfer pumps back on. As a consequence the LOW FUEL warning illuminated (recorded by the VMS) and the RFM requires a landing within 10 mins. To an experienced pilot this means land ASAP. These two facts are the most significant in the report.
I wonder how many times this situation had arisen where the outcome was favourable.
What you, and many others on this thread fail to appreciate is that in attempting to discredit the fuel contents and indicating system you are actually promoting a culture where indications are no longer relied upon are indeed acted upon.
As such, two habits form. 1. Lack of trust and therefore conservative application of limits OR 2. lack of trust leading to a belief that there is probably more fuel available than indicated.
This aircraft, based on the total contents indicated AND the pilots in flight airmanship was already below the MLA in the OM and he had still not reached his landing site. To me this indicates a habit based on condition 2 above. Complacency leading to mismanagement of the fuel system.
It is remarkable simple if you think about it. With less than 100 kgs in the main tanks at least one or both TRFR pumps needed to be on. I would think that is an obvious requirement regardless of the perceived pressures of the task.
Fuel system indications are a lot more robust that posters on this thread like to intimate. As such, if the LOW FUEL lights illuminate in flight.....hers my to tip. LAND ASAP.
DB
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Originally Posted by Silsosid
There is only one warning system for fuel, the one that produces the FUEL LOW 1 & FUEL LOW 2 warnings on the single warning panel.
(or are we getting into a debate on semantics?)
the FUEL LOW 1 & FUEL LOW 2 warnings alarms are just that, last resort alarms, in normal circumstances you should never see these come on, or are you trying to suggest it's good practice to ignore your fuel gauges and carry on till you hit FUEL LOW 1 & FUEL LOW 2?
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There is still the note in the report to consider.
While the warning about fuel was logged in the computer, is it clear that the warning was actually displayed on the display? The report appeared to promise more on this later in the investigation, and that may be very pertinent.
While the warning about fuel was logged in the computer, is it clear that the warning was actually displayed on the display? The report appeared to promise more on this later in the investigation, and that may be very pertinent.
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Scuffers,
Is it yet clear what was displayed/annunciated/chimed? Not in time, but in total?
Are you confident that there are no mechanical/indication issues to be addressed or revealed in a more complete report, before the human factors take the stage alone?
Edited - not intended to revisit known details - but to emphasize that the AAIB did note and are continuing to investigate this failed display issue, as highlighted by SilsoeSid below. The experts seem to be clear that the suggested failure could remove cautions not warnings from view/hearing.
Is it yet clear what was displayed/annunciated/chimed? Not in time, but in total?
Are you confident that there are no mechanical/indication issues to be addressed or revealed in a more complete report, before the human factors take the stage alone?
Edited - not intended to revisit known details - but to emphasize that the AAIB did note and are continuing to investigate this failed display issue, as highlighted by SilsoeSid below. The experts seem to be clear that the suggested failure could remove cautions not warnings from view/hearing.
Last edited by awblain; 25th Feb 2014 at 09:59. Reason: Clarification
Purveyor of Egg Liqueur to Lucifer
I think it is important that we are specific with the terminology we use in respect of warnings cautions and indications.
As I understand it;
Warnings - Warning Panel - Red lights - Gong
Cautions - CAD display - Yellow lights - sometimes with 'beeps'
Indications - Other instrumentation
To put your quoted above post into context DB, this was in reply to your previous post;
.
As the report, that I'm sure you must have read, says, "The Central Panel Display System (CPDS) displays cautions and fuel status information to the pilot. It also records internal display system faults but no information relating to its indications."
The only recorded warnings were from the warning unit, as mentioned in the report, that I'm sure you must have read, "The Warning Unit has provided information on the order in which warnings were triggered during the flight but not when they occurred."
Therefore it stands that, as you quoted me saying - "There is only one warning system for fuel, the one that produces the FUEL LOW 1 & FUEL LOW 2 warnings on the single warning panel."
So, to answer your post;
my bracketed letters
a. Indications and cautions.
b. Not semantics, correct terminology.
c. No I'm not.
As I understand it;
Warnings - Warning Panel - Red lights - Gong
Cautions - CAD display - Yellow lights - sometimes with 'beeps'
Indications - Other instrumentation
Scuffers
Originally Posted by Silsosid
with respect, what do you call the fuel gauges and amber warnings then?
(or are we getting into a debate on semantics?)
the FUEL LOW 1 & FUEL LOW 2 warnings alarms are just that, last resort alarms, in normal circumstances you should never see these come on, or are you trying to suggest it's good practice to ignore your fuel gauges and carry on till you hit FUEL LOW 1 & FUEL LOW 2?
Originally Posted by Silsosid
There is only one warning system for fuel, the one that produces the FUEL LOW 1 & FUEL LOW 2 warnings on the single warning panel.
(or are we getting into a debate on semantics?)
the FUEL LOW 1 & FUEL LOW 2 warnings alarms are just that, last resort alarms, in normal circumstances you should never see these come on, or are you trying to suggest it's good practice to ignore your fuel gauges and carry on till you hit FUEL LOW 1 & FUEL LOW 2?
I think the pilot did not understand the fuel system. Thats why the transfer pumps were off. The VMS recorded the correct warnings and they were ignored. As was the flight manual requirement to land. As was the Company OM MLA requirement. Airmanship in terms of time/fuel calculations also ignored. In fact just about every safety break in place had been breached. Finally a poor response to double OEI
As the report, that I'm sure you must have read, says, "The Central Panel Display System (CPDS) displays cautions and fuel status information to the pilot. It also records internal display system faults but no information relating to its indications."
The only recorded warnings were from the warning unit, as mentioned in the report, that I'm sure you must have read, "The Warning Unit has provided information on the order in which warnings were triggered during the flight but not when they occurred."
Therefore it stands that, as you quoted me saying - "There is only one warning system for fuel, the one that produces the FUEL LOW 1 & FUEL LOW 2 warnings on the single warning panel."
So, to answer your post;
(a) with respect, what do you call the fuel gauges and amber warnings then?
(b) (or are we getting into a debate on semantics?)
the FUEL LOW 1 & FUEL LOW 2 warnings alarms are just that, last resort alarms, in normal circumstances you should never see these come on, (c) or are you trying to suggest it's good practice to ignore your fuel gauges and carry on till you hit FUEL LOW 1 & FUEL LOW 2?
(b) (or are we getting into a debate on semantics?)
the FUEL LOW 1 & FUEL LOW 2 warnings alarms are just that, last resort alarms, in normal circumstances you should never see these come on, (c) or are you trying to suggest it's good practice to ignore your fuel gauges and carry on till you hit FUEL LOW 1 & FUEL LOW 2?
a. Indications and cautions.
b. Not semantics, correct terminology.
c. No I'm not.
Purveyor of Egg Liqueur to Lucifer
Scuffers;
Yes, BUT as people keep saying, that's just one warning, what about all the indications/warnings before this?
Yes, BUT as people keep saying, that's just one warning, what about all the indications/warnings before this?
awblain;
While the warning about fuel was logged in the computer, is it clear that the warning was actually displayed on the display?
.
.
Is it yet clear what was displayed/annunciated/chimed? Not in time, but in total?
While the warning about fuel was logged in the computer, is it clear that the warning was actually displayed on the display?
.
.
Is it yet clear what was displayed/annunciated/chimed? Not in time, but in total?
"The Warning Unit has provided information on the order in which warnings were triggered during the flight but not when they occurred. The unit recorded the normal warnings associated with starting the helicopter, followed by a warning free status. It subsequently recorded intermittent LOW FUEL 1 warnings for the left fuel supply tank, then a permanent LOW FUEL 2 warning for the right fuel supply tank. This was followed by a further temporary LOW FUEL 1 warning, before it became permanent for the remainder of the flight. These LOW FUEL warnings are triggered by thermal sensors in the supply tanks.
.
.
An alarm gong was also recorded followed by intermittent warnings relating to low rotor rpm. The penultimate warning recorded related to the battery discharging, which occurs when there is insufficient engine-driven generator power. The last warning related to an autopilot system failure. Investigation into the possible causes for the individual warnings is continuing."
However as you must have clicked on a link to the report, that I'm sure you both must have read, you must already know that, so what was the question?
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Despite the mods advice people are still repeating previously answered questions, and still using confusing half fact terminology.
Sid has told you, there is one warning system.
There are no amber warnings.
ALL of the CAUTIONS would have been displayed on the ONE CAD screen.
The AAIB report only comments on the WARNING panel not the CAD, because the cautions are not recorded.
If the CAD was not on due to fault/power loss (the AAIB are still investigating a display fault) then NONE of the cautions and Fuel information would have been displayed.
The Red Fuel Low WARNING would have been the very first and ONLY indication to the front seat occupants that there was a problem with the location of the fuel, if that warning did not display in time for the RFM '10 minutes to land drill' to be actioned because of sensor inaccuracy previously experienced (on other 135s) we can see how it MIGHT have left the crew with little if any time to act before flame outs occurred.
I do think that once and IF these issues have been robustly proved not to be the case, the pilots actions will rightly become the focus of attention.
Sid has told you, there is one warning system.
There are no amber warnings.
ALL of the CAUTIONS would have been displayed on the ONE CAD screen.
The AAIB report only comments on the WARNING panel not the CAD, because the cautions are not recorded.
If the CAD was not on due to fault/power loss (the AAIB are still investigating a display fault) then NONE of the cautions and Fuel information would have been displayed.
The Red Fuel Low WARNING would have been the very first and ONLY indication to the front seat occupants that there was a problem with the location of the fuel, if that warning did not display in time for the RFM '10 minutes to land drill' to be actioned because of sensor inaccuracy previously experienced (on other 135s) we can see how it MIGHT have left the crew with little if any time to act before flame outs occurred.
I do think that once and IF these issues have been robustly proved not to be the case, the pilots actions will rightly become the focus of attention.
Last edited by Art of flight; 25th Feb 2014 at 08:40.
Purveyor of Egg Liqueur to Lucifer
Some may be asking why so much talk about display systems;
http://www.aaib.gov.uk/cms_resources...4%20G-SPAO.pdf
The last few pages of this thread have given the scenario that the CAD had failed, yes this is purely speculation and conjecture.
However, this has highlighted the problems that this would cause, including such things as a total loss of fuel indication and the loss of the majority of cautions being displayed if the circumstances arose, such as the low fuel caution, the prime pumps on caution and the transfer pumps off/dry caution.
As a consequence of a CAD failure, the only indication of the aircrafts fuel state would be the LOW FUEL 1 & LOW FUEL 2 warnings on the warning panel and their associated 'Gong' audio warnings.
In the latest report (Special Bulletin S2/2014), there were at least 4 seperate red warnings that appeared in reference to the fuel state and each time they would have also produced a 'Gong' in the i/c system.
my brackets to total up the warnings, 4+
The big technical question that may never be answered is, when were these warnings and gongs presented to the crew?
However, the biggest question for me is;
Given that 4 minutes before the engines ran dry (22:22), ATC was contacted (22:18)
Approximately 4 minutes before that they were on a task to the East of Glasgow (Bargeddie area is 8 miles away)
The drill for LOW FUEL 1 & LOW FUEL 2 warnings is to land within 10 minutes.
Why would anyone continue to spend 2 minutes on a task with a LOW FUEL warning displayed?
Yes there's no getting away from the reports finding that the switches were not in a 'normal flight' configuration, but it appears to me that the system built in to warn of this, for whatever reason, didn't.
A fault relating to one of the display systems was recorded and further work is being undertaken to establish the meaning and possible causes of the fault.
The last few pages of this thread have given the scenario that the CAD had failed, yes this is purely speculation and conjecture.
However, this has highlighted the problems that this would cause, including such things as a total loss of fuel indication and the loss of the majority of cautions being displayed if the circumstances arose, such as the low fuel caution, the prime pumps on caution and the transfer pumps off/dry caution.
As a consequence of a CAD failure, the only indication of the aircrafts fuel state would be the LOW FUEL 1 & LOW FUEL 2 warnings on the warning panel and their associated 'Gong' audio warnings.
In the latest report (Special Bulletin S2/2014), there were at least 4 seperate red warnings that appeared in reference to the fuel state and each time they would have also produced a 'Gong' in the i/c system.
It subsequently recorded intermittent LOW FUEL 1 warnings for the left fuel supply tank, (1+) then a permanent LOW FUEL 2 warning for the right fuel supply tank. (1) This was followed by a further temporary LOW FUEL 1 warning, (1) before it became permanent for the remainder of the flight. (1)
The big technical question that may never be answered is, when were these warnings and gongs presented to the crew?
However, the biggest question for me is;
Given that 4 minutes before the engines ran dry (22:22), ATC was contacted (22:18)
Approximately 4 minutes before that they were on a task to the East of Glasgow (Bargeddie area is 8 miles away)
The drill for LOW FUEL 1 & LOW FUEL 2 warnings is to land within 10 minutes.
Why would anyone continue to spend 2 minutes on a task with a LOW FUEL warning displayed?
Yes there's no getting away from the reports finding that the switches were not in a 'normal flight' configuration, but it appears to me that the system built in to warn of this, for whatever reason, didn't.
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Purveyor of Egg Liqueur to Lucifer
What if the complete CAD hadn't failed and the fault found so far in the investigation is with one or a couple of the inputs, and a CAU DEGR was on the main CAD?
Any thoughts on what would happen in this scenario if, for example, the transfer pumps weren't switched on at all during the flight?
Any thoughts on what would happen in this scenario if, for example, the transfer pumps weren't switched on at all during the flight?
Any thoughts on what would happen in this scenario if, for example, the transfer pumps weren't switched on at all during the flight?
Are you suggesting the Prime Pumps got turned on during the Engine Start Procedure and never got turned off.....and the Transfer Pumps never got turned on?
It would have been a very much shorter Flight wouldn't it?
Purveyor of Egg Liqueur to Lucifer
It would have been a much shorter flight!
What is the fuel endurance of an EC-135 if the Transfer Pumps are not turned on during the Start....and left off during the flight. Start with the assumed 400KG of Fuel they had at the start. How long would you have been able to fly?
Purveyor of Egg Liqueur to Lucifer
Are you suggesting the Prime Pumps got turned on during the Engine Start Procedure and never got turned off.....and the Transfer Pumps never got turned on?
Assuming a normal start, if for some reason the transfer pumps were somehow left off or not operational how would the fuel flow work out?
As the initial job was to look for someone struck by a train, would some consider that enough to complete a 'fast start'?
Purveyor of Egg Liqueur to Lucifer
What is the fuel endurance of an EC-135 if the Transfer Pumps are not turned on during the Start....and left off during the flight. Start with the assumed 400KG of Fuel they had at the start. How long would you have been able to fly?
From the report, "Using an average fuel consumption of 200 kg/hr" (3.33 kg/min)
… about 97 minutes!
20:45 to 22:22 = 1hr 37 minutes!
So....Transfer Pumps serve no function?
Why the concern about the Transfer Pump Switches?
Why the concern about the Transfer Pump Switches?