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FAI into Clutha crash opens

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FAI into Clutha crash opens

Old 16th Apr 2019, 11:17
  #41 (permalink)  
 
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Delta-Ng. - your last 2 posts - Spot on.

Pittsextra - option B - know what you have to start with and updated / re-assessed as you go.
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Old 16th Apr 2019, 11:31
  #42 (permalink)  
 
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Pittsextra,

the trouble is fuel flow is not at a constant rate. Demands in S&L flight at 110 kts say could be a chunk less than sitting in the hover. Taking off with an hours worth of fuel, is that at best endurance or highest likely fuel flow required?
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Old 16th Apr 2019, 12:41
  #43 (permalink)  
 
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Well quite but the general point being that with your expected endurance of 1 hour (via one assumes a combo of calculated/finger in the air from experience of your expected mix of best endurance v max fuel flow) if you see a fuel alarm at 50mins then surely your first thought is "oh i hadnt realised id been so greedy with the fuel today" rather than "the alarm is erroneous lets push on".?? Even with the fuel remaining had the aircraft landed successfully at its home goodness knows how these guys are living if landing with so little is standard.
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Old 16th Apr 2019, 13:29
  #44 (permalink)  
 
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Originally Posted by Pittsextra View Post
Well quite but the general point being that with your expected endurance of 1 hour (via one assumes a combo of calculated/finger in the air from experience of your expected mix of best endurance v max fuel flow) if you see a fuel alarm at 50mins then surely your first thought is "oh i hadnt realised id been so greedy with the fuel today" rather than "the alarm is erroneous lets push on".?? Even with the fuel remaining had the aircraft landed successfully at its home goodness knows how these guys are living if landing with so little is standard.
Landing with so little???? 80kgs is more than the VFR FRF.
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Old 16th Apr 2019, 15:20
  #45 (permalink)  
 
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FRF / MLA is a limit not a target.
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Old 16th Apr 2019, 15:46
  #46 (permalink)  
 
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Originally Posted by Fortyodd2 View Post
FRF / MLA is a limit not a target.
Obviously not an Offshore pilot because the FRF is often all that's left unless the air gods have been kind and left a little contingency to sweeten the deal!
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Old 16th Apr 2019, 15:55
  #47 (permalink)  
 
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Correct, not an Offshore Pilot - and if that's the "Offshore Attitude" to FRF / MLA then glad I stayed clear of it.
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Old 16th Apr 2019, 17:08
  #48 (permalink)  
 
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FRF Should give you 20 minutes at loiter (VFR) and 30 minutes (IFR) and still be able to land safely.
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Old 16th Apr 2019, 17:14
  #49 (permalink)  
 
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Originally Posted by DeltaNg View Post
FRF Should give you 20 minutes at loiter (VFR) and 30 minutes (IFR) and still be able to land safely.
HI Delta
Unless my memory has let me down again, the VFR requirement is based on 20 mins cruise whilst the IFR requirement is 30 mins at holding speed - in the end they tend to produce a similar value.
Cheers
TeeS
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Old 16th Apr 2019, 18:44
  #50 (permalink)  
 
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It’s so simple you say. Start the clock and you should know what your endurance is?

WRONG

I have got airborne in a helicopter with faulty fuel gauges. They SHOWED 1:30 fuel but were over-reading by 15 minutes worth. In other words the fuel was not there at the start. It got very tense when the other warnings came on.

The only time you can be confident of your contents is when the tank is brimmed full or empty.

If this aircraft had faulty gauges, it could have lifted with god only knows what in the tanks. The stopwatch call would be irrelevant

As I said above, it happened to me
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Old 17th Apr 2019, 06:32
  #51 (permalink)  
 
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Originally Posted by Fortyodd2 View Post
Correct, not an Offshore Pilot - and if that's the "Offshore Attitude" to FRF / MLA then glad I stayed clear of it.
FortyOdd, I like your feeling towards this and cannot fault you for wanting to avoid being low on fuel. It sucks and always will. However, its not an "Attitude" in HOFO its sometimes a commercial necessity and the Commander needs to be comfortable with it otherwise he can take "Additional Fuel required by the Commander" as is his prerogative under the rules. Majority of HOFO Pilots I have worked with like to take as much fuel as they can get in but sometimes the client wants all the available payload. That's the nature of the job. However, you can bet your pay packet that on those occasions we is watching the fuel gauges with deep suspicion until we land safely. We employ lots of little tricks to justify a little more fuel like planning with winds more punitive than forecast so the system calculates more fuel. It takes a really brave soul to plan minimum wx/absolute minimum fuel without at least a tweak here and their for the "wife and kids". Often this happens subconsciously during the planning. One day the bean counters will eventually stand over our shoulders and the cat will get out of our nav bag. Rue the day!!
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Old 17th Apr 2019, 06:48
  #52 (permalink)  
 
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Originally Posted by DOUBLE BOGEY View Post
Landing with so little???? 80kgs is more than the VFR FRF.
Are we not nit picking? Using your 80kgs and the averged 3.3kg/min consumption at the point it fell through a roof, and that roof was a distance away from the planned landing site and absolutely no margin for any precautionary alternative....at night.

You can make general points at the margin but fundementally you know how much fuel has been uplifted and the watch gives you the rest. If your SOPs and crew allow you to operate such that a couple of dozen kgs of fuel make the difference it hardly seems logical that this same crew are not then super attentive to all of the information presented to them around fuel including where that fuel is.
That will not be answered because all are dead but what can be is the acceptance or otherwise of the fuel management process. I doubt very much that a similarly operated aircraft could crash with similarly low levels of fuel remaining as far away from its base today, which suggests SOPs will have been revised, suggesting the process that allowed this situation to occur was flawed.
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Old 17th Apr 2019, 22:11
  #53 (permalink)  
 
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We are not nit picking. FRF figures are guidlines which are determined by Operators and Regulators with safety in mind as a sensible amount of fuel to land with as a minimum.

Fundamentally we all know how much fuel has been uplifted, and everyone who has flown for 20 years commercially is super attentive, but suddenly one day we don't just ignore a whole load of fuel warnings without some other factor in play.
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Old 18th Apr 2019, 07:42
  #54 (permalink)  
 
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Delta NG, that last line says it all
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Old 19th Apr 2019, 14:22
  #55 (permalink)  
 
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"There are many holes in the cheese that needed to line up. Some of them are already there, now, in our own working environments. Finding the holes and plugging them is the mission."
2 layers of cheese with 2 holes each is easy to avoid holes lining up
4 layers with 300 holes each is very difficult.

Tight on fuel to assure engine accountability during takeoff is clearly a false safety trade-off.
Complexity leads to pilot error. Pilot error is about 4/5ths of accidetnts.
Complexity increases the probability of System Failures. About 1/5th of Fatal accidents are system failures.

Engines 1%.
Complexity kills. (to paraphrase Occam: "a helicopter should have a single reliable engine")

There is a level of engine reliability at which the extra risks (of 2 engines) are not worth it.
Anyone got a handle on what that figure is? IS THERE AN EXPERT out there?
Should be easy to calculate. Probably somewhere around the 10^-3 to 10^-6 mark. Trying to improve on that risks shooting one's self it the foot with an overcomplicated gun.

"a pilot who understands the EC135 fuel system should NEVER end up with fuel starvation provided..."
and the number of pilots that don't is? : 1 per 100,000? 1 per 1000? 1 per 10?
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Old 20th Apr 2019, 06:30
  #56 (permalink)  
 
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ANFI we all know what your bee in your bonnet is and it has f***k all to do with this accident.
One day you will grow up and realise you live in the real world where problems are real. Not imagined. Not hypothesised. Just real.
DeltaNg summarises this event very well in his last line. I would add, given the nature and background of the pilot that night..........there is most probably more to this story than what the current evidence implies. The subject pilot deserves at least that consideration.
BTW he was 2 minutes from landing at his home base. His calculated FRF would have been intact. If the events had not unfolded as they did it would have been just another professional pilot exploiting his available endurance efficiently to serve the public.
That is what this is about. Complexity and no of engines play no significant part.
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Old 20th Apr 2019, 06:47
  #57 (permalink)  
 
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Pitts. UPLIFTED FUEL. In professional aviation we make a big effort to ratify/verify the amount uplifted against the difference on the fuel gauges before and after refuel. But it is meaningless if the gross amount displayed before refuel is already erroneous AND we did not fill and witness to the brim.

Read/listen to what is being written. Anecdotal evidence of fuel indicating in the supply tanks that wasn’t there.

FUEL ENDURANCE - unless you are Stephen Hawkins, mentally calculating the predicted fuel consumption on a Police Ops flight is practically impossible. Hovering, balls-out, loiter type circling and everything in between was taking place on this flight. Other than a vague notion of what could have been used the pilot could easily be 10-20% out. Thus a very heavy reliance on gauge indications is necessary. And that is assuming the value indicated at all stages of flight is correct.
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Old 20th Apr 2019, 07:10
  #58 (permalink)  
 
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Double Bogey- spot on

For the record, it may not have happened in this case. BUT, if the aircraft had the same fault that happened to the Barton aircraft a few days later and was discovered in a few aircraft in the fleet check, then that’s a game changer. What if the fuel wasn’t ever in the tanks at take off? All the stopwatches in the world wouldn’t have helped.

However, even if the fault had been present, there was enough belt and braces systems to give the pilot the information he needed.

IF HE HAD BEEN TAUGHT AND UNDERSTOOD THE FUEL SYSTEM PROPERLY

Not looking for an excuse, just looking for a reasonable understanding of why Dave might have been confused
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Old 20th Apr 2019, 17:39
  #59 (permalink)  
 
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Unfortunately, like an icicle used as a dagger, hard evidence of the fuel displays status & the water which caused the capacitance probes to fail has long since evaporated.

But I'd like to think others would consider the possibility that the professional pilot perhaps wasn't entirely to blame for this horrific event.
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Old 20th Apr 2019, 18:35
  #60 (permalink)  
 
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Originally Posted by DeltaNg View Post
But I'd like to think others would consider the possibility that the professional pilot perhaps wasn't entirely to blame for this horrific event.
Originally Posted by DrinkGirls View Post
However, even if the fault had been present, there was enough belt and braces systems to give the pilot the information he needed.

IF HE HAD BEEN TAUGHT AND UNDERSTOOD THE FUEL SYSTEM PROPERLY

Not looking for an excuse, just looking for a reasonable understanding of why Dave might have been confused
I agree with these 2 sentiments. From them and the pages of educational discussions on the EC135 fuel system, it is clear that it IS complex enough to expect a pilot failure rate. I don't think it's the pilots fault, just the complexity of what is required of him will result in accidents.

DB also 'Fuel Pressure', is a real world cause of accidents. AND "in the real world where problems are real. Not imagined. Not hypothesised. Just real." like this real world multiple fatal accident or Leicester? OR the imaginary world where engine redundancy is an imagined magic cure?
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