Timeline for How can the fuel decrease evenly from both wing tanks when an A320 is running on APU only?
Current License: CC BY-SA 4.0
15 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Sep 4, 2020 at 16:50 | comment | added | Jai | @AnasMaaz yes our company's engineers operated the refuel control panel and the mode selector positions. | |
| Sep 4, 2020 at 16:48 | history | edited | Jai | CC BY-SA 4.0 |
added 1288 characters in body
|
| Sep 4, 2020 at 16:36 | comment | added | Anas Maaz | I believe your engineers operated the refuel panel then? That clears it up. | |
| Sep 4, 2020 at 15:55 | comment | added | Jai | @janhudec hope that answered your question. The fuel doesn't pass over the fuel pumps but goes through the refuel gallery to the open refuel valve the fuel inturn goes to the outer tank which spills over to the inner tank. I'm cass of the A321 there are only wing tanks and no outer and inner tanks | |
| Sep 4, 2020 at 15:52 | comment | added | Jai | @AnasMaaz in terms of fuel transfer the entire procedure was followed as per the FCOM ground fuel transfer procedure. Again as i mentioned I only explained the cockpit control changes we did and how that helps. To actually move fuel in between tanks as mentioned by you the defuel/xfr position has to be selected. Once done that valve opens. After opening of that valve again as mentioned by you we shut the refuel valve of the non recieving tank and open the receiving tanks side. The pumps in turn provide the necessary pressure to move the fuel. The fuel flows through the refuel gallery. | |
| Sep 4, 2020 at 14:44 | comment | added | Anas Maaz | And I am still very interested in knowing how you transferred fuel between tanks with X feed and tank pumps. | |
| Sep 4, 2020 at 14:42 | comment | added | Anas Maaz | @jai I am talking about your comment on how fuel is transferred in cockpit. Regarding the main question, I think OP asked why specifically the fuel burn is same between inner tanks in the 'fuel leak' procedure. That is exactly what is in the question. And I answered that. | |
| Sep 4, 2020 at 14:21 | comment | added | Jai | Also the procedure explained by you is the whole procedure as mentioned in the FCOM. Which is correct I only explained what system controls were manipulated while in the cockpit. | |
| Sep 4, 2020 at 14:13 | comment | added | Jai | @AnasMaaz you have addressed the fuel leak checklist. I am well aware of this procedure and what the FCTM also says. I have specifically addressed the doubt of the question as to how can fuel decrease evenly from both fuel tanks when only the APU is running. | |
| Sep 4, 2020 at 13:47 | comment | added | Anas Maaz | @JanHudec I am not sure how Jai did it. I hope he gives us a more detailed answer. The time I had to do it, it was a bit more tedious. You have to first turn on the wing tank pumps (the side you want to transfer fuel from), and then turn on cross feed. Then you have to go outside and on the refuel panel, set the refuel mode selector to Defuel/ XFR and then the refuel valve of the receiving tank to on. That should start the transfer. And you are right, the X feed is in the engine supply line. It cannot transfer fuel between tanks as far as my knowledge is concerned. | |
| Sep 4, 2020 at 5:21 | comment | added | Jan Hudec | @Jai, but how does the fuel actually get into the tank when you do that? The cross-feed valve connects to the feed line, which is connected to the tanks via the pumps on both sides, so the fuel can't flow directly into the tank. Either it has to be able to go back through the pumps when they are off, or flow around the engine and through the return lines. | |
| Sep 4, 2020 at 4:22 | comment | added | Jai | @JanHudec as far as the system function goes it's very simple you need some form of pressure to move the fuel from either sides tanks while on ground with the engines shut off. So in this case if we want to transfer fuel for example from the right tank to the left tank we will first open the cross feed valve and then switch on the right hand side tanks fuel pumps on. While running the pumps will now provide sufficient fuel pressure to allow the fuel to flow through the cross feed valve to other sides tanks. I have also had this situation while on ground during the refueling. We followed this. | |
| Sep 3, 2020 at 19:45 | comment | added | Jan Hudec | @wbeard52, the diagram (see the linked question) calls it a cross-feed valve and it does seem to be a cross-feed valve, connecting the left and right feed lines, not the tanks themselves. I am not sure how it works for transfer (either it can flow back through the pumps when they are off, or makes a detour through the engines and return lines) | |
| Sep 3, 2020 at 18:44 | comment | added | wbeard52 | Just out of curiosity. Is it actually called a cross-feed valve or a cross-flow valve. In my mind, a cross-feed system takes fuel from a different tank than normal and directly supplies it to the engine. In other words, the fuel doesn't flow from one tank to another for the engines to burn it... that would be a cross-flow system. | |
| Sep 3, 2020 at 17:53 | history | answered | Jai | CC BY-SA 4.0 |