Camel Fuel Gauge?

[RNAS10_Oliver]

I've just been doing some practice landings and etc with the Sopwith Camel. I am noticing that the fuel gauge tube shows empty when taking 30 percent (50 litres) and shows full when taking 36 percent (60 litres). Due to this seems to be more use as a "low" fuel warning indicator. I did not seem to remember the same being the case in Rise of Flight so I've just gone and installed the game. And indeed the fuel gauge tube in Rise of Flight does not have such an limited range indicated.

 

Anyone know how and what the fuel gauge tube indicated in the real life Sopwith Camel?

 

I am curious whether the manner in which I am seeing it function in Flying Circus is an error or something fixed to resemble real life compared to the Rise of Flight version. And if the latter then am interested to know how the tube functioned and what it indicated about the tanks levels (which are 136 and 32 litres according to google searching) etc.

Edited August 29, 2019 by Oliver88

[unreasonable]

I am happy to be proved wrong, but after having thought about your question I would say that RoF is wrong and FC is right. Quite apart from the general expectation that the developers are learning rather than "unlearning", the design of the gauge suggests the FC treatment is better.

 

It is certain that the fuel gauge contains actual fuel connected by fuel lines to the main tank. I think - with considerably less certainty - that the gauge is a simple open tube with a connection to the tank top and bottom, in effect an extension of the tank, so that the level of the fuel in the tank is level with the level of the fuel in the tube. In that case, for the tube to show 0-100% of the range of fuel contents, it would have to be as deep - top to bottom - as the fuel tank. Which it is not.

 

This also seems to suggest that the level of the fuel in the tube might alter if the plane is pitching up or down, although in the game it seems not to. There may well be some valve arrangement to prevent the level in the tube changing too rapidly.

 

I am quite possibly wrong about this, since I cannot find a primary source, in which case someone will come along soon enough to shoot down my hypothesis - in flames.    

Edited August 29, 2019 by unreasonable

[SeaW0lf]

I noticed the difference a while ago and it would be nice to confirm it right or wrong (Camel enthusiasts anyone?). If it is the latter, we can report the bug.

[SeaW0lf]

So Kermit explains with some detail how the gauge works on the Snipe. He starts talking about the fuel at 13:26, and at 15:27 he talks about the pump system and how the gauge works (but it is good to watch from 13:26 onwards). It might be different on the Camel, but it might give us an idea. I'm not used to engines and such, so his explanation wasn't that clear to me.

 

 

[BMA_Hellbender]

From a historical perspective, I really have no idea. Fuel gauges were notoriously unreliable. Still are on modern planes.

 

From a software development point of view, if there’s a subsystem or function that behaves differently from (pre-2014) RoF, it should be treated as a defect until rejected by the devs. We can add this to the list of Albatros engine seizure at prolonged max AoA climb (may very well have been a real problem) and Halberstadt CL.II gun angle reduction (gunner compartment was notoriously cramped).

[unreasonable]

The Camel fuel gauge - as is the case on some other aircraft - is a sight gauge. Effectively the pilot is just looking into the tank through a transparent window. There is no mechanical gizmo to go wrong, as far as I can see.  See this page on Camel reconstruction. 

 

http://www.johnsshawaviation.co.uk/wordpress/le-clerget-9ba-rotary-engine/sopwith-camel-fuel-system/

 

And these picturs showing size of the tank and guage.  While I cannot find a photo or drawing that shows both tank and gauge together, it looks fairly obvious to me that the tank is much longer, top to bottom, than the gauge.

 

 

 

[Zooropa_Fly]

I knew it was there, but now I've seen pic #1 above.. I'm not sure I want to fly it again.

[Trooper117]

This should help...

 

[JGr2/J5_Baeumer]

Looks like a simple sight guage that's of (roughly) the bottom half or bottom quarter tank of fuel, which of course, would be of the most interest to any pilot.

[RNAS10_Oliver]

12 hours ago, Trooper117 said:

This should help...

 

 

Erm sorry perhaps I am missing something but I'm not sure what help showing a labeled picture from Rise of Flight provides? It's how the gauge functions and what the guage at full/empty indicates about your fuel tanks in Flying Circus compared to Rise of Flight that we are confused over. We are not confused over where the fuel gauge is located.

 

19 hours ago, Zooropa_Fly said:

I knew it was there, but now I've seen pic #1 above.. I'm not sure I want to fly it again.

 

Be glad then that we do not have the Snipe then huh given that Kermit states in the Snipe "the fuel that I am sitting on".

Edited September 1, 2019 by Oliver88

[unreasonable]

3 hours ago, Oliver88 said:

 

Erm sorry perhaps I am missing something but I'm not sure what help showing a labeled picture from Rise of Flight provides? It's how the gauge functions and what the guage at full/empty indicates about your fuel tanks in Flying Circus compared to Rise of Flight that we are confused over. We are not confused over where the fuel gauge is located.

 

I think he is saying that if you look at 1) where the gauge is located, 2) how long it is, 3) that it is a sight gauge, and 4) refer back to the size of the the main tank in the previous pictures, it is simply impossible for the gauge to show 0-100% of the fuel, so RoF is wrong.

 

The other thing to bear in mind is that the Camel had two fuel tanks - the main pressurized tank that the gauge measures, and a gravity tank. This would be useful in situations where your Rotherham pump (powered  by the little windmill) might fail and you have no time to use the manual pump to maintail fuel pressure. The RoF/BoX "fuel gauge" somehow has to take into account the contents of both tanks although it only measures one in RL. This simplification is generally true for all BoX planes, although I think modelling the contents of tanks a separate entities is in the work pipeline. 

[Trooper117]

8 hours ago, Oliver88 said:

 

Erm sorry perhaps I am missing something

 

 

Oliver,  I couldn't help you directly... but other people looking at this thread with interest who have never played RoF or FC, may not even be aware where or what the fuel gauge looks like in a Camel.

[Cynic_Al]

13 hours ago, unreasonable said:

 

I think he is saying that if you look at 1) where the gauge is located, 2) how long it is, 3) that it is a sight gauge, and 4) refer back to the size of the the main tank in the previous pictures, it is simply impossible for the gauge to show 0-100% of the fuel, so RoF is wrong.

 

 

 

It's not clear, but the the routing of the top tube connected to the gauge appears to be aft, suggesting it leads either to the rear gravity tank or to the selector valve, in which case perhaps it serves whichever tank is selected. In practice it probably was used as a 'not empty' indicator.

 

The RoF/BoX "fuel gauge" somehow has to take into account the contents of both tanks although it only measures one in RL. This simplification is generally true for all BoX planes, although I think modelling the contents of tanks a separate entities is in the work pipeline. 

 

That would entail the player having to switch between tanks. as required  I can't see that happening for WW1 types.

[unreasonable]

2 hours ago, Cynic_Al said:

 

It's not clear, but the the routing of the top tube connected to the gauge appears to be aft, suggesting it leads either to the rear gravity tank or to the selector valve, in which case perhaps it serves whichever tank is selected. In practice it probably was used as a 'not empty' indicator.

 

That would entail the player having to switch between tanks. as required  I can't see that happening for WW1 types.

 

You may well be right about the second point - we will see.  The top tube I think goes back to the main tank and connects at the point visible in the first of the pictures in my previous post at about the middle of the tank: at least it does in one of the scale models pictures I found! 

 

Anyway, this little mystery has motivated me to order the Haynes Sopwith Camel Manual, which should arrive in a week or so. Perhaps that will have a clearer answer.   

[RNAS10_Oliver]

13 hours ago, Trooper117 said:

 

Oliver,  I couldn't help you directly... but other people looking at this thread with interest who have never played RoF or FC, may not even be aware where or what the fuel gauge looks like in a Camel.

 

Ah fair enough, an incase anyone comes wondering in here as they are wanting to find where a fuel gauge might be found in the Camel.

 

[unreasonable]

Haynes Sopwith Camel book arrives: no relevant technical drawing unfortunately, but there is another photo of the partially rebuilt Camel - same one as in my earlier post - showing the top fuel lines from the tank to the gauge.  The top line goes into the attachment half way up the main tank visible in the post above. I cannot scan at the moment. 

 

Here is a horribly out of focus drawing of the tanks from another source:

 

 

 

 

So I stick with my hypothesis: the FC treatment is a much better simulation of what the pilot would observe in a real Camel than is seen in RoF, assuming he saved the gravity tank until his gauge showed empty.

 

The FC cockpit gauge is modelling the contents of only the main tank. It is just an open(able) tube connected to the main tank, so that the top of the fuel in the gauge finds it's own level with the fuel in the tank. The top tube is needed to equalize pressure.

 

When the sight gauge reaches the bottom you have 50lt left altogether, as the OP observes. That is about 25lt in the gravity tank plus about the same again left in the bottom of the main tank - I assume because the sight gauge cannot "see" low levels as the bottom of it is a little higher than the bottom of the main tank. To say if the FC amounts (gauge full and empty)  is exactly right one needs a complete drawing showing the level of the gauge and main tank.