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flyby797
31st Aug 2014, 12:14
Hi everyone,
I do not know if this question has already been addressed here. If it is the case please bear with me.
Our B737NG fleet is all ETOPS (LOW FUEL at 2000 lbs/907 kgs per tank as per FAA ETOPS requirement to alert flight crew when fuel level reaches half an hour at MCT on both engines) and we fly them on ETOPS and non ETOPS flights.
Our final reserve as per local regulation is around 1.1 t. My question is: Is it normal when flying normal ops to end up in abnormal ops? i.e.: having a close ALTN can give us an arrival fuel at DEST (ALTN fuel + FINAL RSV) below LOW FUEL alert. The question was asked at Boeing who answered that the operator should address this issue. I do know that some colleagues consider FINAL RSV equal to the LOW FUEL alert. I wanted to know if some of you out there have the same issue and if some operators addressed it.
Thank you

BOAC
31st Aug 2014, 12:29
It was certainly a discussion point before I retired in 2008, where CMRs could be below 1800kg thus in theory requiring QRH action on reaching. I don't know if the issue has been addressed anywhere. The 'problem' only arose when the optional higher fuel state was introduced and as such in reality it does not constitute a 'crisis' since it used to be 'ok' to fly around above the lower warning level without action - and the engines have not changed!

May I suggest a formal query to your airline on how they expect crews to treat such a warning during 'normal' operations. They might wish to consider making CMR 1820 minimum? ...(or not........:))

Skyjob
31st Aug 2014, 19:16
This is certainly the case where ETOPS configured FUEL minimums for LOW alert are set and the flight is used on non-ETOPS sector.

Please bear in mind that Boeing refers to Operator (AO) as the Operator defines its own fuel policy based on local national legislation which thus may only require an mount less then the one where the alert is triggered.

The reason for referring to Operator is thus to enable the Operator to advise crew this possibility exists under certain conditions on (part of) its fleet. Boeing is unable to comment on Operator procedures as they are not involved in OMA etc defining such, but only to aircraft manufacturer defined manuals, FCTM, FCOM, etc

Piltdown Man
31st Aug 2014, 22:08
What action has to be taken with a LOW FUEL alert? If it is mainly a crew awareness message and a check to make sure the pumps are on and/or a pitch limit, does it really matter?

framer
1st Sep 2014, 02:08
What action has to be taken with a LOW FUEL alert?
Cross feed valve to open.

BOAC
1st Sep 2014, 07:06
Not forgetting the performance limitations for things like go-rounds, normal and TCAS climbs and descents, speed changes, speedbrake usage etc etc?

No Fly Zone
4th Sep 2014, 12:32
Ha! Even when the initial cost of a new airplane is $60Mil or $250Mil, whether one is buying one (perhaps a BBJ) or thirty, to upgrade a sand fleet, there are so many questions. While virtually no hardware is changed, the operating software is different for every buyer. A few standard packages are already certified, but unusual requests often require engineering and in-flight proof - and yes, that is expensive. Boeing will do it is one pays enough (or buys enough airplanes) and Airbus is reluctant, but can be pushed. Certificated modifications to the 'basic' operating software for today's new jets is certainly possible, but it can be extremely expensive. Smart BBJ operators accept the best off-shelf package; huge operators (sand airlines?) may buy a few changes to accommodate temperatures, and smart airlines buy what is available. Ever wonder why "Launch Customer" is important to some? For the most part, they get software modifications free, in exchange for their fleet-wide testing. If they already want a dozen or more copies, and generally fly routes within the marketing envelope, this can be a sharp move. The one or two-off operator cannot afford it.
Buying new airplanes at multip-$millions per copy is not easy. Unless buying to another's spec., it take at least 9-12 months to wiggle out the finer details - and ever change has a price. (Glad that I no longer sell them! I may keep my hand in, but I hate airplanes - or love them... I've never been sure which...):confused::ugh: .

flyby797
6th Sep 2014, 12:15
Thank you for your time and answers.
@BOAC Company was queried and we are still waiting for an answer...:ugh: As for "disregarding" the alert knowing that it is not an issue of uncovered fuel pumps, you understand that it is not a solution and cannot be tolerated.
@Piltdown Here's the note that we can read at the head of the LOW fuel C/L:
Note: Avoid high nose up attitude. Make thrust changes slowly and smoothly. This reduces the possibility of uncovering fuel pumps. Plus the cross feed
@skyjob I totally understand Boeing position and fully agree with it
The solution would be normally to put CMR at the highest alert level...or a software change on nonETOPS flights....

Skyjob
6th Sep 2014, 12:44
@flyby797: "The solution would be normally to put CMR at the highest alert level...or a software change on nonETOPS flights...."

Changing software or in this case pin settings costs money.
Crew instructions from AO do not...

BOAC
6th Sep 2014, 13:17
@BOAC Company was queried and we are still waiting for an answer... As for "disregarding" the alert knowing that it is not an issue of uncovered fuel pumps, you understand that it is not a solution and cannot be tolerated. - it sounds like an 'Ostrich' company to me. (Yes, I understand:))

If they persist in 'ignoring' this problem - they have caused - why not start with PAN calls and ASRs and see how they like it. WE both know the solution is VERY simple - and in their hands.