Thank you! The venturi explanation (including the air-brush example) helps so much! I've been trying to figure out how the feeder tank is fed reliably even in zero gravity for a few hours, this video finally gave me the answer!
Thank you, your videos are great to watch. I have been out of flying for 9 months on the ATR 600 series and welcome the visual refresher which is optimum learning for me.
Graet video as usual 🙂. Regarding the question what force moves fuel from vent tank to the main tank - this is the slight air overpressure above the fuel in the vent tank , provided by the profile of the NACA duct in fligt. It overpress and turns back the fuel from vent tank to the main tank. Thank You Capt. Magnar for the great work!
Yes, you are right. FCOM states that there's one drain valve in each tank. I missed that and used an inaccurate drawing as reference. Thank you for correcting me.
Captain, thanks for clear fuel system explanation. I have a question: How can I to identify whether fuel leak between feeder tank and HP fuel pump (Video 19:27) or fuel leak between HMU and Fuel Flow meter (Video 20:12)? Both have the same indications: “FUEL UNBALANCED” + Fuel Used 210L/210R + Fuel QTY 780L/990R + FF 340L/340R + ELEC PUMP RUN. Best regards: Carlos.
Hi capt, would like your explanation on, why is there only 1 fuel temperature indicator on left feeder tank, is there any specific reason? Thank you…very knowledgeable video!
Hello Magnar, being new to the ATR's systems a question from watching this video: does anti skid only work when normal brakes are used, or does anti skid also work when braking from the accumulator when normal brakes are lost? Best regards, Boy
@@FlywithMagnar Thank you for that very quick reply! I now see that I posted my question in the wrong video but the answer is very much appreciated even if not linked to fuel system at all :-))
Hello again Captain! I'm running through your videos today! I had another question. The only reason why the low level light would come on while the tank is still showing more than 160kg could be because there is a leak in the feeder tank. The checklist says keep fuel crossfeed closed in this case. But according to the diagram you have showed in the video, I don't see why the crossfeed cannot be opened, since the line runs directly to the LP on the other side without mixing with the fuel in the affected feeder tank? Also question 2: the unusable fuel is 130kg in the tank according to the same checklist, does this mean the engine will quit at 130kg? Is this figure accounted for in your alternate aerodrome calculation by your computer flight plan?
Hi, there might be several reasons for why the feeder tank is not full. Examples: 1) Fuel leak from the feeder tank (as you mentioned). 2) A clogged jet pump preventing the feeder tank to be filled up. 3) A leak in the line from the feeder tank to the LP valve. If the latter is the case, use of crossfeed will result in unnecessary loss of more fuel. Since the pilots cannot determine the cause, the most conservative procedure is applied. Question 2: Unusable fuel is 130 kg only if the feeder jet pump has failed. Since the pilots cannot determine the cause for the fuel low level alert (when the fuel quantity is >160 kg), the most conservative procedure is applied. (FCOM PRO.NNO.ABN.28)
Thank you so much captain, I'm preparing for command interview! Your videos give me the confidence about the aircraft! Your help is greatly appreciated
Gravity. The fuel tanks are above the engines. If you forget to select the electrical pump ON before start, there's already fuel in the line, and the HP pump will very soon assist the gravity by sucking more fuel from the feeder tank. However, the motive flow valve remains closed as long as the fuel pump is selected OFF. Therefore, the feeder tank will not be topped up, and you will sooner or later receive a LO LVL alert. That should wake you up!
Thank you for the video about fuel systems. Does FOB number must always be inputed manually into the flight management system? Do pilots get this number only from refueling handling staff?
Yes, FOB must be entered manually into the FMS. No, we read the fuel quantity indicators. The point is that FOB and the fuel quantity indicators show the same numbers when we start the engines. The refuelling handling staff give us a receipt showing how much fuel they have added to the tanks. For example, if we landed with 800 kg in the tanks and ordered 2,000 kg, we should have received 1,200 kg / 0.785 = about 1,530 litres. If the receipt show something very different, we must find out why. It happened to me once; we received 200 litres more than the receipt showed. The refuelling staff insisted he was right. If he was right, then our indicators were wrong. We used the magnetic indicators to cross-check that the fuel indicators were correct. This is the only time I have used them.
Capt Nordal, May i ask whats ur take on MEL on ATR 72-600 28-42-1 FUEL QTY INDICATION It says Number installed 2 does ATR mean 2 as 1 in cockpit MFD and 1 in refueling panel or 1 quantity indicator for each wing in MFD??
There are two fuel quantity indicator systems, one for each tank. The fuel quantity in each tank is shown in the cockpit and the refueling panel. One of those tweo fuel indication systems may be inoperative for dispatch, provided you comply with the conditions in MEL, including checking the fuel quantity in the affected tank by using manual (magnetic) indicators after each refueling.
Hi captain, thanks for your video. I do not understand why if there is an excessive fuel flow the checklist tell us to operate the xfeed valve. Excessive fuel flow is an engine leak so with xfeed the leak will still be there ?
In the QRH, there's no checklist for excessive fuel flow. The nearest checklist is FUEL LEAK. Here, it is written: "If excessive fuel flow was identified before engine shutdown: FUEL X FEED VALVE CAN BE OPENED." That means you can use fuel from both tanks to feed the operating engine. The reason is, when you see excessive fuel flow, the leak is after the fuel flow meter for that engine. The fuel tanks are not affected.
@@FlywithMagnar thank you for this quick answer. I probably miss something but what I understand it’s that if you open the cross feed valve you will continue to feed the leaking engine and so the failure will remain ?
@@Xavieralberici, no, the engine is shut down as prescribed by the checklist. The failure is in the engine, not the fuel tank. Watch from 20:22 in the video.
Captain, sorry for asking one more question, what if the leak is confirmed from the tank? The cabin crew tells you that there is spray from the wing, you only have a fuel unbalanced alert, I would keep the engine running, the electronic checklist gives you a choice, either ,leak from engine or not located....in this scenario (leak from the tank) it would be not located, is it correct? Thanks a lot
Currently, I don't have access to the electronic checklist. If there's a discrepancy between the electronic checklist and the QRH, then the QRH has priority. QRH procedure: If leak from engine? No. (Don't shut down the engine.) If leak not located? No. (You can use cross-feed.)
@@FlywithMagnar Thank you for your answer, the ECL is the same as the QRH, I thought you had to choose one of the options, that's why it didn't make any sense for me in case of a leak from the wing tank (leak not located, when indeed it is , and close the xfeed), now it's clear, according to your answer, there is no need to shut the engine down, and you can keep engine running with x-feed open, but you have to be sure 100% that the leak is from the tank, again thank you, really appreciated
The temperature in the left fuel tank is more or less the same as the temperature in the right fuel tank. Therefore is only one temperature sensor required.
Finding the single engine rate of climb requires some serious calculations. Instead, we calculate maximum weight that enables us to climb at a specific gradient and to clear obstacles after take-off and during go-around. At 22 tons in standard atmospheric conditions, the single engine ceiling is 14,400 ft. The numbers vary considerably with aircraft weight and temperature. You might find it interesting to watch this video: th-cam.com/video/AIfwMy-rhig/w-d-xo.html
The ecotank is empty when the engine is running. Therefore, a leak can only be detected after the engine is shut down and there's fuel in the ecotank. I'm not a mechanic, but troubleshooting should be quite easy, as the ecotank is located below the engine and is relatively easy to access.
The fuel delivery pressure is less than 4 PSI. Probable causes: 1. The assosicted fuel pump is selected OFF. This closes the motive flow valve. Therefore, the first line in the FUEL FEED LO PR checklist is to verify that the fuel pump is ON. 2. Jet pump failure + electrical fuel pump failure. 3. The motive flow valve is jammed shut + electrical fuel pump failure. 4. Something is partially blocking the fuel from flowing from the tank to the engine. 5. Fuel leak between the fuel tank and the pressure sensor. This might result in a significant loss of fuel from the associated tank. In that case, the procedure is to shut down the engine (and hope that there will be no fire).
The engine will run fine with the fuel pump selected off. The low pressure light should not be illuminated, because the engine driven fuel pump will suck fuel from the tank.
If the valve does not open, there will not be any blue light on the refueling panel. If manual control does not help, the option will be fueling by gravity.
@@FlywithMagnar or-use the tool provided with the airframe & open the valve manually. Remember-you will have NO overfill protection & will need to close the valve manually by removing the tool allowing the refuel/defuel valve to close.
Thank you! The venturi explanation (including the air-brush example) helps so much! I've been trying to figure out how the feeder tank is fed reliably even in zero gravity for a few hours, this video finally gave me the answer!
Thanks, this saved me a few hours in the FCOM.
Thank you, your videos are great to watch. I have been out of flying for 9 months on the ATR 600 series and welcome the visual refresher which is optimum learning for me.
Lol
We really appreciate your videos very helpful...thank you
Perfect explanation… Thanks Magnar!
Dear sir, your explanation is very good.i do learn it simply.
Thanks Magnar, very useful review👍
Thank you very much for your videos, they have been a great help. Keep them coming captain.
Really appreciate these in depth tech videos, cheers
Graet video as usual 🙂. Regarding the question what force moves fuel from vent tank to the main tank - this is the slight air overpressure above the fuel in the vent tank , provided by the profile of the NACA duct in fligt. It overpress and turns back the fuel from vent tank to the main tank. Thank You Capt. Magnar for the great work!
Thanks for the info!
Thank you very much, great help, I have been out of fliying for 9 months and those videos are amazing helphul
Amazing work there Magnar.
For ATR 72-600 In minute 1:22 the inboard water drain valve is for feeder compartment and the other is for wing tank
Yes, you are right. FCOM states that there's one drain valve in each tank. I missed that and used an inaccurate drawing as reference. Thank you for correcting me.
you're welcome capt
Excellent explanation , Magnar..amazing videos always
Thanks for the videos , great for a refresher !!!!
Thanks a lot captain for the informative videos . Waiting for your next video on engine oil system.
It's in the making! However, the engine is a large subject. It's more than the oil system. It takes a little more time before the video ready.
Captain, thanks for clear fuel system explanation. I have a question:
How can I to identify whether fuel leak between feeder tank and HP fuel pump (Video 19:27) or fuel leak between HMU and Fuel Flow meter (Video 20:12)? Both have the same indications: “FUEL UNBALANCED” + Fuel Used 210L/210R + Fuel QTY 780L/990R + FF 340L/340R + ELEC PUMP RUN. Best regards: Carlos.
great video, thanks for your effort
One of the most simple fuel systems around-dang near bullet proof.
Hi capt, would like your explanation on, why is there only 1 fuel temperature indicator on left feeder tank, is there any specific reason? Thank you…very knowledgeable video!
The fuel temperature is, under normal operations, identical in both tanks.
Hello Magnar, being new to the ATR's systems a question from watching this video: does anti skid only work when normal brakes are used, or does anti skid also work when braking from the accumulator when normal brakes are lost? Best regards, Boy
Hello Boy. Anti-skid only works with normal brakes. The emergency brake does not have anti-skid.
@@FlywithMagnar Thank you for that very quick reply! I now see that I posted my question in the wrong video but the answer is very much appreciated even if not linked to fuel system at all :-))
Very nice review thank you
Hello again Captain! I'm running through your videos today!
I had another question. The only reason why the low level light would come on while the tank is still showing more than 160kg could be because there is a leak in the feeder tank. The checklist says keep fuel crossfeed closed in this case.
But according to the diagram you have showed in the video, I don't see why the crossfeed cannot be opened, since the line runs directly to the LP on the other side without mixing with the fuel in the affected feeder tank?
Also question 2: the unusable fuel is 130kg in the tank according to the same checklist, does this mean the engine will quit at 130kg? Is this figure accounted for in your alternate aerodrome calculation by your computer flight plan?
Hi, there might be several reasons for why the feeder tank is not full. Examples: 1) Fuel leak from the feeder tank (as you mentioned). 2) A clogged jet pump preventing the feeder tank to be filled up. 3) A leak in the line from the feeder tank to the LP valve. If the latter is the case, use of crossfeed will result in unnecessary loss of more fuel. Since the pilots cannot determine the cause, the most conservative procedure is applied.
Question 2: Unusable fuel is 130 kg only if the feeder jet pump has failed. Since the pilots cannot determine the cause for the fuel low level alert (when the fuel quantity is >160 kg), the most conservative procedure is applied. (FCOM PRO.NNO.ABN.28)
Thank you so much captain, I'm preparing for command interview! Your videos give me the confidence about the aircraft!
Your help is greatly appreciated
hi captain, amazing videos, i always use them before going to sim. i had a question, how are we able to start the engines with the electric pump OFF?
Gravity. The fuel tanks are above the engines. If you forget to select the electrical pump ON before start, there's already fuel in the line, and the HP pump will very soon assist the gravity by sucking more fuel from the feeder tank.
However, the motive flow valve remains closed as long as the fuel pump is selected OFF. Therefore, the feeder tank will not be topped up, and you will sooner or later receive a LO LVL alert. That should wake you up!
Thank you for the video about fuel systems.
Does FOB number must always be inputed manually into the flight management system? Do pilots get this number only from refueling handling staff?
Yes, FOB must be entered manually into the FMS. No, we read the fuel quantity indicators. The point is that FOB and the fuel quantity indicators show the same numbers when we start the engines.
The refuelling handling staff give us a receipt showing how much fuel they have added to the tanks. For example, if we landed with 800 kg in the tanks and ordered 2,000 kg, we should have received 1,200 kg / 0.785 = about 1,530 litres. If the receipt show something very different, we must find out why.
It happened to me once; we received 200 litres more than the receipt showed. The refuelling staff insisted he was right. If he was right, then our indicators were wrong. We used the magnetic indicators to cross-check that the fuel indicators were correct. This is the only time I have used them.
@@FlywithMagnar Very interesting story. Thank you very much for extensive answer
Capt Nordal,
May i ask whats ur take on MEL on ATR 72-600
28-42-1 FUEL QTY INDICATION
It says Number installed 2
does ATR mean 2 as 1 in cockpit MFD
and 1 in refueling panel
or 1 quantity indicator for each wing in MFD??
There are two fuel quantity indicator systems, one for each tank. The fuel quantity in each tank is shown in the cockpit and the refueling panel. One of those tweo fuel indication systems may be inoperative for dispatch, provided you comply with the conditions in MEL, including checking the fuel quantity in the affected tank by using manual (magnetic) indicators after each refueling.
@@FlywithMagnar appreciated capt
safe skies 🙂
Thank you for another great video captain! Any thoughts about doing one for the engine\propeller systems?
It's in the making!
Hi captain, thanks for your video. I do not understand why if there is an excessive fuel flow the checklist tell us to operate the xfeed valve. Excessive fuel flow is an engine leak so with xfeed the leak will still be there ?
In the QRH, there's no checklist for excessive fuel flow. The nearest checklist is FUEL LEAK. Here, it is written: "If excessive fuel flow was identified before engine shutdown: FUEL X FEED VALVE CAN BE OPENED." That means you can use fuel from both tanks to feed the operating engine. The reason is, when you see excessive fuel flow, the leak is after the fuel flow meter for that engine. The fuel tanks are not affected.
@@FlywithMagnar thank you for this quick answer. I probably miss something but what I understand it’s that if you open the cross feed valve you will continue to feed the leaking engine and so the failure will remain ?
@@Xavieralberici, no, the engine is shut down as prescribed by the checklist. The failure is in the engine, not the fuel tank. Watch from 20:22 in the video.
@@FlywithMagnar that was the element missing : the leaking engine off. Thank you 🛫🛫
Terimakasih Capt 👍👍👍👍👍
Thank you from your time
tahnks for ur video really help me
Captain, sorry for asking one more question, what if the leak is confirmed from the tank? The cabin crew tells you that there is spray from the wing, you only have a fuel unbalanced alert, I would keep the engine running, the electronic checklist gives you a choice, either ,leak from engine or not located....in this scenario (leak from the tank) it would be not located, is it correct? Thanks a lot
Currently, I don't have access to the electronic checklist. If there's a discrepancy between the electronic checklist and the QRH, then the QRH has priority. QRH procedure: If leak from engine? No. (Don't shut down the engine.) If leak not located? No. (You can use cross-feed.)
@@FlywithMagnar Thank you for your answer, the ECL is the same as the QRH, I thought you had to choose one of the options, that's why it didn't make any sense for me in case of a leak from the wing tank (leak not located, when indeed it is , and close the xfeed), now it's clear, according to your answer, there is no need to shut the engine down, and you can keep engine running with x-feed open, but you have to be sure 100% that the leak is from the tank, again thank you, really appreciated
Thank you Captain
Good morning Cap Magnar and thanks for this, whay there is only one a temperature detector on the left feeder tank
The temperature in the left fuel tank is more or less the same as the temperature in the right fuel tank. Therefore is only one temperature sensor required.
@@FlywithMagnar thousand tanks for your soon answer captain Magnar
Just out of curiosity what is the climb rate and single engine ceiling for ATR 72 at normal conditions and normal operating weight ?
Finding the single engine rate of climb requires some serious calculations. Instead, we calculate maximum weight that enables us to climb at a specific gradient and to clear obstacles after take-off and during go-around.
At 22 tons in standard atmospheric conditions, the single engine ceiling is 14,400 ft. The numbers vary considerably with aircraft weight and temperature.
You might find it interesting to watch this video: th-cam.com/video/AIfwMy-rhig/w-d-xo.html
THANKS FOR MANY TIMES
Is there any specific reason to have the FUEL TANK TEMP probe only on Tank 1
Yes, the fuel temperature in each wing tank is more or less the same. Therefore, it is not necessary to install temperature sensors in both tanks.
Can i ask? Do you encounter during hotelmode we have fuel leak on ecotank drain and what troubleshooting you give or advise
The ecotank is empty when the engine is running. Therefore, a leak can only be detected after the engine is shut down and there's fuel in the ecotank. I'm not a mechanic, but troubleshooting should be quite easy, as the ecotank is located below the engine and is relatively easy to access.
Hi captain! On ground engine is running --> Feed Lo Pr, what could cause this? thanks
The fuel delivery pressure is less than 4 PSI. Probable causes:
1. The assosicted fuel pump is selected OFF. This closes the motive flow valve. Therefore, the first line in the FUEL FEED LO PR checklist is to verify that the fuel pump is ON.
2. Jet pump failure + electrical fuel pump failure.
3. The motive flow valve is jammed shut + electrical fuel pump failure.
4. Something is partially blocking the fuel from flowing from the tank to the engine.
5. Fuel leak between the fuel tank and the pressure sensor. This might result in a significant loss of fuel from the associated tank. In that case, the procedure is to shut down the engine (and hope that there will be no fire).
@@FlywithMagnar Thank you Captain
Sir, i Want to ask, if fuel full tank at ATR-72 600 how many hours aircraft can flying, ?
Thank
Around 7 hours. Total capacity is 5,000 kg. For quick planning, we calculate 800 kg for the first hour and 700 kg for the next hours.
@@FlywithMagnar where i can get refensi for this capt, cause this my home work, thank a lot before
The fuel consumption depends heavily on the cruise level. The reference is found in FCOM PER (Performance).
Thank sir
Hallo sir, can you give me, fcom spesifik about this fuel consumtion if full tank
Hi Magnar Norwegian ?
thank you!!
Hi Captain
Question
The engine keeps running whith fuel pump off ?
Yes, the electrical fuel pump is only needed to start the engine. The engine drives a HP fuel pump, which has a much better capacity.
I mean with Push Button off with low pressure alarm
The engine will run fine with the fuel pump selected off. The low pressure light should not be illuminated, because the engine driven fuel pump will suck fuel from the tank.
Thanks a lot Captain
Actually that's the way to cross fuel when engine still running, thanks for videos
Thank for you sir
Roger that capr
If the left hand refuel valve failed?
If the valve does not open, there will not be any blue light on the refueling panel. If manual control does not help, the option will be fueling by gravity.
@@FlywithMagnar or-use the tool provided with the airframe & open the valve manually. Remember-you will have NO overfill protection & will need to close the valve manually by removing the tool allowing the refuel/defuel valve to close.
thanks
Whether ac can be filled by avtur indrum?
*_An electric pump is used to return fuel from the ventilation tank to the main_* ""🤣🤣🤣caaa💥boom"" did not wanna say that that's why😂
Blue skies.