Fuel Quantity Selector Switch

[KewlerMouh]

Good day everyone!

 

Beyond the Fuel Qty indicator is the Fuel Selector Switch, which you can operate (standard mapping is Ctrl + D). It has the following working settings:

FEED - INT WING - TANK1 - EXT WING - EXT CTR

 

In the new Belsimtek manual is no explanation about the switch (page 44),

so supposed with 3 external drop tanks the different settings mean:

FEED - first the external tanks, then internal

INT Wing - self explanatory

TANK 1 - is this the internal tank in the fuselage?

EXT WING - the two external drop tanks at the wing, whose amount is indicated with "LEFT/RIGHT" above?

EXT CTR - the center external drop tank

 

Then there is the setting BIT below FEED, is this the Fuel Quantity Indicator Test button?

 

1) Can please anyone confirm or explain my assumptions?

 

2) Is anybody using any other setting as FEED and if, in which way and for what purpose?

 

Thank you in advance :)

[blkspade]

It has no real function other than to display how much fuel is left in a given tank. Your assumptions are mostly right though feed is only internal. There isn't much to be gained by switching the display, especially if you already know that 13,455 is the point where you are using internal fuel. Since the fuel is consumed equally (and incorrrectly) from all 3 external tanks simultaneously, there isn't even a proper point to drop the wing tanks while retaining the center.

[Robin_Hood]

The switch is the Fuel Quantity Indicator switch, and only changes the display. Actually, it only affects the LEFT and RIGHT counters at the bottom of the indicator.

 

Two things you need to remember:

 

1. The TOTAL counter and the pointer are not dependant on the switch position. The TOTAL counter always indicate total fuel (all internal + all external), while the pointer always indicate total internal only.

 

2. The LEFT and RIGHT counters are tied to the switch.

 

So for FEED, INTL WING and EXT WING, the LEFT and RIGHT counters indicate the fuel left in the left and right feed tanks, wings, and external wing drop tanks, respectively.

 

For the TANK 1 and EXT CTR, the LEFT counter indicates the fuel left in the Tank 1 (main internal fuselage) and external center drop tank, respectively.

 

The CONF position indicates fuel in the left and right CFT, but as they are unavailable in DCS, they will always show 0.

 

For fuel systems this page has some good info, though it has not yet been updated per the new working indicator switch.

 

Hope this helps :book:

[KewlerMouh]

Allright, it's clear to me now! I thought (and hoped) you can fiddle here around, like I used to play in the blackshark with the fuel pumps to steer the amount of fuel in the fwd and aft fuel tanks.

 

Anyway, thank you both very much for the explanatian!

[Akula]

I'm kinda in the same dilemma. My question is; assuming you have it set to FEED where the external tanks are used before the internal tanks, why don't both counters below the gauge lower as the external wing tanks are depleted? Makes sense to me or maybe I'm backwards on this.

[feefifofum]

The feed tanks are internal, and always refill themselves from any external tanks you may be carrying...for an example, try reducing your internal fuel to 10%, then adding wing tanks. As you fly, you'll see the bags pump into your internal tanks until either they're full, or the bags are empty. So, it's not exactly that external tanks are used first directly, it's that external tanks pump into the feed tanks, which supply fuel to the engines. Make sense?

The only way to monitor the precise amount of fuel in the external tanks is to change the fuel quantity selector to the external wing position.

[Delta99]

I use it to keep watch of external tanks so that I can drop them when needed

[GGTharos]

FEED just shows you the amount of fuel left in the FEED TANKS. It doesn't actually tell the fuel system to do anything.

 

FEED tanks are always supplied from the internal tanks and are kept as full as possible - they feed the engines directly, which is why they are called feed tanks.

 

You could deplete feed tanks before you deplete your fuel, thus causing the engines to shut down: You can do this by having very high AB consumption (very rare but possible), keeping your refueling slipway open or flying at 0g or less for more than a certain amount of time.

 

If you want to view the amount of fuel left in the EXTERNAL tanks, move the switch to point to the appropriate setting.

 

I'm kinda in the same dilemma. My question is; assuming you have it set to FEED where the external tanks are used before the internal tanks, why don't both counters below the gauge lower as the external wing tanks are depleted? Makes sense to me or maybe I'm backwards on this.