The fuel tank selector of Cessna 207 does not have a BOTH position. Any idea please?
I assumed the real plane does not have it.
Fuel is supplied to the engine from two tanks, one in each wing. Usable fuel in each tank, for all flight conditions, is 29 gallons for standard tanks and 38.5 gallons for long range tanks. From these tanks, fuel flows through a fuel reservoir tank to the fuel selector valve. Depending upon the setting of the selector valve (fuel cannot be used from both fuel tanks simultaneously), fuel from the left or right tank flows through a by-pass in the electric auxiliary fuel pump and fuel strainer to the engine-driven fuel pump. From here fuel is distributed to the engine cylinders via a fuel control unit and manifold. Vapor and excess fuel from the engine-driven fuel pump and fuel control unit are returned by way of the selector valve to the reservoir tank of the wing system being used.
Dear:
Thanks for the detail info.
But in the sim, while switching from left tank to right tank, there is an OFF position. The selector first goes to OFF, then to Right. In OFF position, engines starves fuel and sometimes shuts down. How can I avoid this OFF position?
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Added tag.
Same question from yours truly here in the main 207 thread:
Do it quickly. There’s plenty of planes with similar fuel switching mechanisms. As long as you don’t starve it completely and force a shutoff.
Also check the procedures for the aircraft in question when switching tanks, as that model may require you to turn the fuel pump on when switching.
eg:
http://www.askacfi.com/2778/switching-fuel-tanks.htm
Cautionary tale:
@Sonicviz, that’s not what happens IRL and there’s no need to do it quickly because the engines continues to operate without power loss with the selector in the OFF position until the fuel from the fuel line has been used.
Sim is not real life, they’re models made by many developers of differing skill levels and quality. Just sayin. I’ve had engines cut out quickly in a transition off position in a few sim planes, so obviously the residual fuel in the lines isn’t well modelled (if at all) and it takes the cue from the fuel switch (more or less I guess).
So it’s add on dependant . You (as in anyone, not you specifically) should do your own testing per plane to confirm the tolerance of residual fuel in case of fuel off position impacting the engine state.
Or perhaps, just do it quickly😂
I don’t have the 207 so can’t speak to that, my comments are “in general” for sim aircraft.
The reaaon why I replied was to clarify that this is a bug in the game, so armchair pilots don’t believe that this happens IRL as well.
It’s not “a bug in the game”, it’s inconsistently applied fuel system behaviours on an individual aircraft level. It’s just another thing to understand about how well a specific aircraft may be modelled.
I don’t blame any dev for not fully modelling the fuel system to that level of detail anyway. It’s a bit of work, even a “simple” aircraft has a few variables to consider there. iirc there are some that have had a stab at it, but could be wrong.
In any event, there’s no logical reason to dawdle in the off position while switching tanks in either case. You’ll find out soon enough if there’s a switch/switching issue causing a fuel starvation problem.
