Systematic fuel warning after 10mn flight

[Sagal]

Hi guys, I do not fly often anymore, so I cannot tell exactly when the problem started (update 7?). Maybe it is something obvious I don’t know about. The fact is that whatever campaigns or theaters I’m using (tom’s korea 2015, tom’s 2014, if I remember correctly the original KTO, the latest Balkans or the latest IT) after 6 to 10 mn of flight, I heard a warning signal sound, then “Fuel” is displayed on the HUD and will stay blinking, then after a while, there starts to be an imbalance in fuel consumption (I would say between left and right tanks as the needles are not moving at the same speed/together anymore), then after a while I will run out of fuel despite the fact that the original fuel load should have be sufficient to conduct the full mission.

How can I fix this problem (apart from desinstalling an reinstalling F4 bms)? Any idea?

Thanks in advance.

[Raptor]

Left console > fuel panel > ENG FEED knob, do you have this on the NORMal position? Error is a imbalanced / trapped fuel state, surly happening after AB takeoff, that explains your distance covered before the error appears. Are the rest fuel-related switchology positioned correctly?

[mrwell]

And is you Steerpoint 1 in the correct position? Bingo is calculated with that waypoint.
Cheers!

[Shadow]

Reinstall with out all the addons/mods, then post back if you still have a problem.

[Dee-Jay]

… nothing related to add ons nor theater.

Check your ENG FEED knob and steerpoints selection.

EDIT: learn how fuel alarms are working and when they are triggered: https://www.benchmarksims.org/forum/showthread.php?9763-BMS-Dash-One-Manual-4-32

[Ironman53rd]

If in doubt “read the instructions” :uham:

[Blu3wolf]

@Sagal:

“Fuel” is displayed on the HUD and will stay blinking

How can I fix this problem?

Right click on the WARN RESET switch position on the upfront controls. This will remove the FUEL warning until it is recalculated by a change in parameters (for instance, if you go below the DTC bingo and then reset it, the FUEL warning will be displayed again once you go below HOM bingo calculation, and vice versa).

Cannot recommend appropriate dash thirty four guidance enough.

[b_bong12]

99% air source isnt to normal. right console

[Dee-Jay]

@b_bong12:

99% air source isnt to normal. right console

This would also trigger a FCR overheat.

[Frederf]

Fuel warnings are the pilot-set BINGO level and <800 lbs. HOME calculated value.

I tried to play with the qty selector knob to get the peticular behavior (interval v. total) with the warnings but I couldn’t get BINGO to go off with internal fuel below the set value but total above. Apparently when the qty switch is out of norm the values reported to the FCC for fuselage fuel are frozen which makes it much less likely to trigger bingo by internal total instead of total.

I was remembering that bingo would re-warn you every time the fuel was halved since the last bingo but that’s Falcon 4.0 behavior and out of date.

[Blu3wolf]

@Frederf:

Fuel warnings are the pilot-set BINGO level and <800 lbs. HOME calculated value.

I tried to play with the qty selector knob to get the peticular behavior (interval v. total) with the warnings but I couldn’t get BINGO to go off with internal fuel below the set value but total above. Apparently when the qty switch is out of norm the values reported to the FCC for fuselage fuel are frozen which makes it much less likely to trigger bingo by internal total instead of total.

I was remembering that bingo would re-warn you every time the fuel was halved since the last bingo but that’s Falcon 4.0 behavior and out of date.

Pretty sure that the fuel and bingo system works as per the dash with regards to the warnings displayed.

some of the CRUS HOM stuff is still not quite correct, but the bingo warnings should be the same as what the real manuals say, rather than say the original F4 manual.

Speaking of the real manuals, they do also predict possible fuel issues related to having the fuel qty sel switch out of norm, too.

[Sagal]

I effectively do not think it is related to addons. What I didn’t say clearly is I also do not have a lot of time for flying, therefore the campaign missions are started engine on on the runway, I do not touch any buttons, just engage after burner and cut it after take off. I’m quite sure my buttons are in Norm position. Why they shouldn’t be there by default anyway? I re-read the BMS dash one manual about that and maybe the imbalance is due to using after burner for too long. I will check again then.

By the way I do not understand the bolded part below (isn’t it the position by default):

"Five conditions must be met for a TRP FUEL warning to occur:
• FUEL QTY SEL knob is in NORM.
• Aerial refuelling has not occurred within the previous 30 - 90 seconds
• Fuselage fuel has been at least 500 pounds less than fuselage capacity for 30 seconds.
• Total fuel has been at least 500 pounds greater than fuselage fuel for 30 seconds.
• Fuel flow has been less than 18,000 pph for 30 seconds
A TRP FUEL warning may also occur with prolonged AB use if fuel flow to the engine exceeds the maximum transfer rate from the external tanks. This is not really a true TRP fuel and will clear as soon as AB is disengaged or when the fuel transfer rate decreases back within the maximum possible transfer rate of the external tanks."

[l3crusader]

Also possible : you took only one drop tank, and your warning is TRP FUEL.

-> solution : take tanks in pair

[Blu3wolf]

@Sagal:

By the way I do not understand the bolded part below (isn’t it the position by default):

Doesnt matter… Trust, but Verify (all switch positions prior to engine start).

Yeah, no time to check all that, starting on the runway and taking off…

Well, if you have any problems that COULD be the result of switches not being set correctly, then your apparent first course of action is to first CHECK those switches - and then start looking for other possible causes.

Ive never seen trapped fuel in BMS due to using AB for too long. In fact, come to think of it, Ive just not seen trapped fuel.

Id start by checking the fuel qty sel knob, the fuel source knob, the DTC BINGO setting, and the loadout.

[Frederf]

@Blu3wolf:

Pretty sure that the fuel and bingo system works as per the dash with regards to the warnings displayed.

some of the CRUS HOM stuff is still not quite correct, but the bingo warnings should be the same as what the real manuals say, rather than say the original F4 manual.

Speaking of the real manuals, they do also predict possible fuel issues related to having the fuel qty sel switch out of norm, too.

The BINGO logic should trigger if for example:

Internal fuel 4000 lbs.
Total fuel 6000 lbs.
Bingo setting 5000 lbs.

In BMS I can’t get the bingo logic to trigger in the case where internal fuel is less than bingo but totalizer is more which is a feature of the real jet.

[Leech]

The Bingo fuel warning is based either on fuselage fuel (ie. internal fuel only) with the FUEL QTY SEL knob in NORM, or on the total fuel (ie. including the fuel remaining in external tanks) with the FUEL QTY SEL knob out of NORM.

With the FUEL QTY SEL knob in NORM, the bingo computation is based on the lesser of fuselage fuel weight or total fuel weight. That is, with the FUEL QTY SEL knob in NORM, bingo fuel warning will be triggered when either fuselage fuel or total fuel decreases below the bingo fuel value.

With the FUEL QTY SEL knob out of NORM, the warning will only be triggered when total fuel decreases below the bingo value. The fuselage fuel is considered to be fixed at 6667lbs, and so a Bingo value set below this will never trigger a Bingo warning. With trapped external fuel, this could lead to fuel starvation before the bingo warning is triggered.

[Blu3wolf]

@Frederf:

The BINGO logic should trigger if for example:

Internal fuel 4000 lbs.
Total fuel 6000 lbs.
Bingo setting 5000 lbs.

In BMS I can’t get the bingo logic to trigger in the case where internal fuel is less than bingo but totalizer is more which is a feature of the real jet.

Out of interest, in BMS how did you get internal fuel less than full with tanks that still have fuel in them?

[Netstat]

@Blu3wolf:

Out of interest, in BMS how did you get internal fuel less than full with tanks that still have fuel in them?

Air Source out of position

[Leech]

@Netstat:

Air Source out of position

yup
trapped fuel in wing tanks

[Blu3wolf]

@Netstat:

Air Source out of position

in what position does it stop pressurising the tanks but still allow FCR operation?