Wing fuel tanks - not correctly operating (need to reopen that topic)

[Gene Z. 2]

Hi,

 

Following up on the topic about incorrect operation of the wing fuel tanks, I checked with the Twin Otter manual & the engines are NOT supposed to quit once the fuel runs out in wing tanks.  See the page from the manual below.  Now, this is from the DHC-6 Series 200 manual, but I am assuming they have not changed this in -300.

(The quote is from PDF page 220, Supplement 11, Auxiliary Wing Tanks.)

 

Actually, I forgot, but I posted on the same topic around Jan 28 (Wing Tanks, under Systems).  And at that time MK stated as follows, regarding possibility of implementing correct tank operation.  So, topic is sort of closed, until further notice ....

 

Quote

Yes, that could be done if we would rewrite the whole fuel system and that is simply not part of this 30 euro project. The issue has been discussed with Microsoft and we have good hopes the fuel system of the sim will be updated soon so it will work fully as the schematics in the manual indicate.

 

Gene

 

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[xiphias 8]

The AUXILIARY WING FUEL TANKS supplement in the 300 AIM says the same thing.

 

Here is an overview of the fuel system. The fuel from the wing tanks are connected to the same fuel line as the main tanks without any switch or valve between them. The fuel supply should just continue uninterrupted from the main tanks when the wing tanks are empty.

 

 

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[EDNR-Cruiser 319]

This looks like a quite modern semi-automatic fuel supply system, not sure if all, especially older variants, were equipped with such a system. I've seen many changes in such details over the production lifespan of an aircraft.
Again, I need to say that I am not familiar with this particular aircraft or series of aircrafts and also don't have that model in any of my flight sims. I am just saying that this might not be a bug at all but just a different original system which was modelled. The Twin Otter was built over a long period of time...

[tommyh454 0]

On the P3D version , wing tip tank empty, low level light on, pumps on , engine runs just fine. 

[xiphias 8]

The 300 AIM with the fuel system schematic concerns all Twin Otter Series 300 with serial numbers 130, 210, 231 to 844 (serial numbers 6 to 115 are Series 100, serial numbers 116-230 are Series 200, but serial numbers 130 and 210 were converted to 300s).

[Aerosoft Team [Inactive Account] 51558]

Okay we'll revisit that. In the mean time just make sure you check your gauges.

[meierzwo 17]

With the latest Update, this Bug is still not fixed. And yes, it is a Bug. In real Life, the Wing Tanks Fuel Pumps have a higher Pressure and override the AFT/FWD Fuel Pumps. If the Wing Tanks run dry, the AFT/FWD Pumps will feed the Engines without interruption. You see the the Pressure Warning Lights for the Wing Fuel Pumps start to Flicker, Fuel Flow for the Wing Tanks stops, Fuel Flow for AFT/FWD Tanks is rising up and you have to shut off the Wing Fuel Pumps. That's all, the Engines never shut down.
With the Aerosoft Twotter, you still have Fuel Flow and Fuel in the Wing Tanks, no Warning Lights for low Fuel Pressure and suddenly the Engines run dry. That's wrong.

[amahran 603]

Yeah, this caught me off-guard. I forgot I had the wing tanks feeding and looked away for 5 minutes. Came back to find my Twotter stalling out of the sky from fuel starvation.

[meierzwo 17]

On Cruise Level (40% Torque, 75% Prop) at 6000 Feet you have Roundabout 45 Minutes of safe Fuel Time if you don't use them earlier for Start or Climb.  The next 5 Minutes are Lottery.  It's still 9,72 lbs Fuel in the Wing Tanks when the Engines running dry. I don't know if the whole Capacity of the Wing Tanks can be used but the Needle is not on Empty.

 

Crosscheck on X-Plane with the Payware Twotter and the very good User Mod.
Needle goes on Empty, Fuel Pump Pressure Warning Light goes on and the Engines are still running from the AFT/FWD Tanks .  As is should be. Fuel Capacity in the Wing Tanks is Zero. The only thing to do is switching off the  Fuel Pumps.
With the Aerosoft Twotter you are now practicing Emergency Procedures.