EC135
Joined: Nov 2005
Posts: 281
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From: UK
May respectfully suggest that all crew go on a FACTORY training course ensuring that they fully and correctly understand the systems they are operating.
BC
Joined: Feb 2006
Posts: 1,067
Likes: 40
From: On the big blue planet
I have asked how you manage the TRANSFER PUMPS to ensure that one is submerged in fuel with the change in pitch attitude with no reply.
My understanding is the one pump may be above the fuel and switched off.
My understanding is the one pump may be above the fuel and switched off.
skadi
Joined: Dec 1999
Posts: 2,584
Likes: 0
From: UK
May respectfully suggest that all crew go on a FACTORY training course ensuring that they fully and correctly understand the systems they are operating.
Would he have the decency to explain the whys an wherefores of this extraordinary accusation, and what evidence he has to support it?
Or else perhaps to apologise fulsomely for such an unwarranted slur against
the Professionalism of those crew alluded to?
For shame.
Joined: Jul 2013
Posts: 59
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From: Uk
I thought these are diaphragm not impeller pumps? I'm sure I read that and would seem to me to be the better choice with these low fuel flow rates.
Joined: Dec 2007
Posts: 160
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From: UK
Robin400 - I'm sure if I ask nicely my CP wont mind if I and the other 70 odd pilots nip over to Germany for a few days at the company's expense for a bit of fuel system training and sightseeing. God knows I could do with it this time of year...
All part of the expense running a safe professional outfit.
Maybe the concern in Germany will pay the bill
Last edited by Robin400; 12th January 2014 at 20:13.
Joined: Dec 2007
Posts: 160
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From: UK
My posts are not intended to be a slur on all pilots involved in the operation of the 135, if you feel that that is the case I apologise unreservedly. I accept that all the posts on here are not from 135 pilots.
From the posts on here I am left with a sense of unease regarding the level of understanding.
From the posts on here I am left with a sense of unease regarding the level of understanding.
Joined: Dec 2007
Posts: 160
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From: UK
Thats the procedure according FLM. A dry running fuelpump gives a CAUTION and has to be switched off. So when in hover atttitude, the FWD pump will be the first when the main tank is coming to around 60 kg. In cruise flight ( nose low ) it will be the AFT pump. You have to consider it, when transitioning to cruise after long hover flight and low fuel in main tank -> AFT pump off and FWD pump ON again!!!
Skadi.
Thank you very much. That is exactly as I imagined it would be.
Joined: Nov 2005
Posts: 281
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From: UK
All part of the expense running a safe professional outfit
There seems to be a lot of concern about pilot familiarity and understanding of the 135 fuel system on this thread from non 135 people. The system hasn't changed markedly from when I was taught about it 7 years ago and I am still happy with how it operates practically day to day as a pilot. I don't feel I need further training and as to all the minute design intricacies etc. I am happy to leave that to the engineers and boffins in white coats.
BC
Joined: Dec 2008
Posts: 843
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From: N/A
10 pages of disagreements about how the fuel system works - uphill syphoning , swirl, pump types, CoG attitude changes, ltrs / kgs water in capacitive fuel senders, confusion about wether one engine should stop first or both might stop at about the same time - leads me to beleive that the understanding amongst the population of 135 pilots is clearly appropriate (not) - carry on.
Anyone with a clear understanding of the system care to explain what scenario leads to a double engine stoppage ? Just incase there is any 135 pilot out there who doesn't know..
What are the combinations of possible failure with 12 hoses 6 fuel pumps and 4(?) non-return valves - does the pilot need to understand that? No - not if it's all working properly i guess.
Remember the A109 in Wales because of the misunderstanding of a transfer pump failure?
Anyone with a clear understanding of the system care to explain what scenario leads to a double engine stoppage ? Just incase there is any 135 pilot out there who doesn't know..
What are the combinations of possible failure with 12 hoses 6 fuel pumps and 4(?) non-return valves - does the pilot need to understand that? No - not if it's all working properly i guess.
Remember the A109 in Wales because of the misunderstanding of a transfer pump failure?
Joined: Feb 2006
Posts: 1,067
Likes: 40
From: On the big blue planet
Quote:
Thats the procedure according FLM. A dry running fuelpump gives a CAUTION and has to be switched off. So when in hover atttitude, the FWD pump will be the first when the main tank is coming to around 60 kg. In cruise flight ( nose low ) it will be the AFT pump. You have to consider it, when transitioning to cruise after long hover flight and low fuel in main tank -> AFT pump off and FWD pump ON again!!!
Skadi. Thank you very much. That is exactly as I imagined it would be.
Thats the procedure according FLM. A dry running fuelpump gives a CAUTION and has to be switched off. So when in hover atttitude, the FWD pump will be the first when the main tank is coming to around 60 kg. In cruise flight ( nose low ) it will be the AFT pump. You have to consider it, when transitioning to cruise after long hover flight and low fuel in main tank -> AFT pump off and FWD pump ON again!!!
Skadi.
Thank you very much. That is exactly as I imagined it would be.
skadi
Joined: Jul 2013
Posts: 59
Likes: 0
From: Uk
AnFi,
Police helicopter crashes onto Glasgow pub, thread. Post 1471
There is also a very good post by Giovanni cento nove back in 2004 I think, about the 135 fuel system, but can't remember what thread.
Ah just found it! Post 83 this thread.
Anyone with a clear understanding of the system care to explain what scenario leads to a double engine stoppage ? Just incase there is any 135 pilot out there who doesn't know..
There is also a very good post by Giovanni cento nove back in 2004 I think, about the 135 fuel system, but can't remember what thread.
Ah just found it! Post 83 this thread.
Last edited by PieChaser; 13th January 2014 at 17:39.
Joined: Jan 2008
Posts: 292
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From: UK
Complexity and permutations as described there make 'pilot error' inevitable - it's a shame they call it pilot error...
Joined: Feb 2006
Posts: 1,067
Likes: 40
From: On the big blue planet
Up to date 44% of the whole fleet have been checked and 2% had faulty indications:
EC135 fuel probe malfunctions in 2% of cases - 1/14/2014 - Flight Global
skadi
EC135 fuel probe malfunctions in 2% of cases - 1/14/2014 - Flight Global
skadi
Chief Bottle Washer
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Aviation Qualifications: ATPL
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From: PPRuNe
Rotorheads A haven for helicopter professionals to discuss the things that affect them
Purveyor of Egg Liqueur to Lucifer
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From: Alles über die platz
Trying to bring the fuel talk here, rather than the Glasgow thread.
AnFI (really!)
"Confusing and unexpectedly complex set of actions!"
LOW FUEL 1 and/or2
Check fuel contents
If pos contents, check XFER pumps on
Check cb's in
If remains on, switch off bleed air
Land within 10 mins
(That Land being an immediate action!)
It is patently obvious that, with such a high unuseable fuel quantity, the cockpit situation faced by this pilot may well have left him with an excessively confusing and unexpectedly complex set of actions. Maybe unpredictable issues of timing wrt Governor response rates and pilot action. Everything points to that.
LOW FUEL 1 and/or2
Check fuel contents
If pos contents, check XFER pumps on
Check cb's in
If remains on, switch off bleed air
Land within 10 mins
(That Land being an immediate action!)