Yes you're right Henry, but it starts with 46/75/43 or whatever, and progresses from there. If you are concentrating on the imbalance, rather than the absolute value in the main tank, and you then saw 46/<fuel>/30...see what I mean?

Reely, thanks for that.

So assuming that the previous weeks fuel samples and the fuel taken from the ac wasn't water contaminated, can we assume that the F QTY DEGR & F QTY FAIL wouldn't have been on?

Also, if no contamination is found on the sensors/ probes, can we also assume that the FUEL light should have displayed as Normal?

If these statements are correct, I'm back to the question, 'What cautions are lost if the CAD fails? :eek:

Just so you can see what you get should the CAD fail or it's turned off;

http://i52.photobucket.com/albums/g1...ps2a7e3479.jpg

Which leaves the question, what cautions are lost with this situation?

http://i52.photobucket.com/albums/g1...ps2a7e3479.jpg

2) Yes. If CAD fails - no fuel indication available !

You will stay only on red warning lights on Warning Panel - LOW FUEL 1 (and LOW FUEL 2), which means that you must be on ground within 10 min (or 8 min in the earlier models)

...and ENG 1 will stop 3-4 minutes after that 10 minutes...and ENG 2 after next 1 and half min!

JR

"All in the green, good to go!" :ok:
(couldn't help, sorry;))

Jet Ranger;
...and the problem with trying to answer serious questions by being cocky, is that you end up cocking it up!

But didn't PPRuNe reach the conclusion that - while the amber caution lights might not be working - them red ones would come on for sure, as they are "driven by an independent measuring system" as EC brags:warning light sequence, acc. to AAIB: http://www.aaib.gov.uk/cms_resources...4%20G-SPAO.pdf
These are red warning lights. Could they have been recorded w/o actually illuminating?
(read: is that a record of the output driver circuit, or some real information about illumination of a light?)

Note: My VW Van knows and records when the central controller activates the break/turn signal/tail light output circuit, and they do not draw expected current.

If the cap fits ....
 

This afternoon has seen some utter ****e posted on this thread!

Scuffers
Take a quick glance across a room at an analogue clock and a digital clock. The information from the analogue clock is clearer and more quickly assimilated than that on the digital display. It is a quirk in human psychological and physical make up that has been proved by numerous experiments. Digital displays may be accurate, but it takes more thought to process that information and make sense of it. This can make a difference in stressful situations.

GOULI -
You think we take LESS notice of fuel at night, even though we know from earlier discussion there are LESS places to refuel at night in the UK? :confused:
I NEVER assume the XFER pumps are on, they either ARE on or a caution (should) tell me they are not.

Also the graphic for the fuel is displayed in such a way (see previous photos) that you can easily read all 3 figures, not look at the main and ignore the supply levels. :rolleyes:

And
I reiterate, you don't just reach up there and blindly switch a pump on and hope for the best! When you switch on a XFER pump you then look at the CAD to confirm the relevant caution has extinguished! :ugh:
In this instance the reason why both XFER pumps were off is unknown, but IMHO the fact the prime pumps were on is significant.

SiloeSid
Since the only major fault found in this incident (so far) is that the fuel prime and transfer switches were reversed from what would be expected in normal operations, the psychological factors that led to them being left that way until the engines flamed out are important. Why wasn't the mis-configuration picked up? Why wasn't the fuel display interpreted correctly? Why were the visual and audio alerts not actioned correctly? These are important issues and in the absence of evidence for mechanical failure we are left with trying to determine why the pilot did not carry out the appropriate drills.

G0ULIHave you read the report?

The graphic is both analogue and digital?

If you see the centre portion blue and the two sides black, you have a problem.

This is not rocket science.

G0ULI

Do you know why and when the pump selections were made???

SilsoeSid and Scuffers
I have downloaded and read the report thoroughly. That is why I am of the opinion that cockpit ergonomics and psychological factors led to a situation where a minor mistake in operating two switches cascaded into an in flight emergency culminating in the needless loss of a serviceable aircraft and many lives. We have a pretty good idea of how the helicopter crashed. The question remains as to why it crashed given that it was a modern design with multiple redundant systems. If there are no major mechanical faults that affected the airworthiness of the aircraft, then it ultimately comes down to human factors.

Back at NH
According to previous posters, the prime pump switches were probably turned on at the conclusion of the final tasking some 20 or so minutes prior to arriving back at Glasgow controlled airspace.

To the best of my knowledge, there is no reason for the prime pumps to be selected on during normal flight. They are only used during engine start and in flight possibly to diagnose abnormal fuel supply problems to an engine.

A prime pump could be used during an attempt to restart an engine in flight although I seem to recall that engine restarts in flight are contrary to advice in the RFM. (I might be wrong on that point).

Isn't it a bit more complicated than "analogue good, digital bad"?

Winding dials can be better for quick comparisons, and for expressing rate information and especially as an array of readings. Digital can be better for exact reading, providing errors, and careful use of colors can highlight both.

I don't see a graphic of tanks with numbers next to them being at all inappropriate to provide information about three volumes/masses (although the meters do seem to read volume/depth here).

That holds true for every minute of the flight....as fuel in the main tank really is of only administrative value.....lack of fuel in the Supply Tank is "Life or Death" value.

If for any reason....at any time after starting the Engine...or Engines...that the Supply Tank is not showing a proper indication for contents for that particular moment of flight...that is a sign of a very significant problem.

Add the Yellow and Red Lights that appear at various times...and you have secondary indications of problems if they occur other than when supposed to appear.

So you don't know. You are making assumptions that

If you really have read the report thoroughly, why do you say, "Since the only major fault found in this incident (so far) is that the fuel prime and transfer switches were reversed from what would be expected in normal operations, ..." :confused:

May I respectfully suggest that you go back to the report and search for the word 'fault'. It should be third in the list!