Police helicopter crashes onto Glasgow pub: final AAIB report

[8Pieced]

Fortyodd - I think you may just have solved the Puzzle!!!!!

FortyOdd I think you have just helped me to solve the mystery!!!! I wish I could shake your hand now!!!!!


I was driving along this evening thinking, 8Pieced you silly ****, how could you forget that you still have the F PUMP FWD or the F PUMP AFT cautions staying on the CAD at the LOW FUEL Warning stage for GSPAO, but seemingly I seem to have not been acknowledging them anymore? See my post 349 to illustrate my apparent stupidity - I promise I will not edit the post.


Then it struck me that hovering, changing to forward flight etc, in the police role, we are getting Fuel Pump cautions all the time, acknowledging them as they flash, switching the pump off then being 'rewarded' by confining that 'ok to have' caution to the top middle of our CAD, then flying around with our 'Ok to have' cautions. So we effectively have a part of the CAD to which we have become used to seeing these cautions, and hence have become almost invisible, and perfectly normal. That is the key here, so imagine what may happen with a fault such as GNWEM/GXMII?


If you can't imagine the significance, reread my post 278 in which I have just edited an important bit in CAPITALS, to reflect my apparent stupidity.


Or I'll quickly explain here. So the F PUMP FWD caution appears over Dalkeith (I'm still absolutely sure that I can prove this could happen in hover attitude at 200 kgs total). The caution is cancelled and then sits as an 'ok to have ' caution on the top middle part of the CAD.


During transit back to Glasgow, the F PUMP AFT caution is activated, we only see the flashing caution, so simply acknowledge it, look up, switch off the pump and don't necessarily recheck the CAD, so we now have the two cautions still sitting in the 'ok to have' area at the top middle part of the CAD, where they could go unnoticed but the next safety kicks in.


So with a correctly indicating fuel system we will get decreasing supply tank levels, which I would say would become noticeable, but even if not, you will then get a flashing FUEL caution. At this point a quick look at fuel supply tank levels will tell you that you have forgotten to put the transfer pumps back on.


But with a faulty fuel system like GNWEM/GXMII you won't have a flashing FUEL caution to acknowledge, and your supply tanks will indicate full and guess what, the two F PUMP cautions are still sitting in the 'Ok to have' area on the CAD!


I rest my case.....how bloody scary?!?!


Once firmly dismissing those Low Fuel Warnings, and lets say it took 1 - 2 minutes to convince the crew that this was ok, the fuel would not have dropped by much in reality 5 kgs, hardly noticeable, needing a bit longer to see that the main tank gauge isn't changing....


Thankyou again Fortyodd for kicking my ass!!