This makes no sense to me

A Living Legend
new reply
JanF
Airman First Class
Posts: 83
Joined: 19 Oct 2018, 14:10

This makes no sense to me

Post by JanF »

When I made a flight with the B17G in P3D 5.2 HF1 I experienced this. Fuel tank 1 and 4 run out of fuel during the flight. The crew informed me that engine 1 and 4 quit. The rpm decreased somewhat. And I could see that the propellers was still turning like before. When I feathered propeller 1 and 4 they did stop.
Two questions here
1) Does engine 1 and 4 only run of fuel from tank 1 and 4 ? That seem somewhat strange since they appear smaller then 2 and 3 in the 2D pop up window.
2) Should not the propeller stop when the engine quit or at least turn very slowly ? Also I did not notice any drop in speed when the engines was told to have quieted ? That seem very strange to me.

alan CXA651
Senior Master Sergeant
Posts: 2438
Joined: 15 Mar 2016, 08:23

Re: This makes no sense to me

Post by alan CXA651 »

Hi JanF.
I dont have P3D or HF1 , i use FSXA and sometimes Active Sky , lets clear some confusion here with regards to
1. fuel tanks , ENG 1 and 4 tanks hold 425 gals of fuel ENG 2 and 3 have two fuel tanks for each eng , but both tanks equal 425 gals. IE on lt load ALL engs have same amount of fuel of 425 gals each .
2. If an engine quits , it will windmill in the airflow , this causes drag and will slow you down , thats why you have to feather the prop , to stop the windmill and reduce drag on dead engine , but you have to be quick , because you cannot feather if oil pressure drops in the engine , as the dead engines oil is used for feathering its prop.
Did you have any faults in the hanger , or did you not fill the fuel tanks to same ammount , also the engines have got to be trimmed out with same prop RPM/MAN and even then you will get uneven fuel burn depending on state of engine ware and hours , this is why you need constant monitoring of systems , so you can spot problems developing and take actions to prevent it as best you can.
regards Alan. 8)
Image
Image
Image
Image

JanF
Airman First Class
Posts: 83
Joined: 19 Oct 2018, 14:10

Re: This makes no sense to me

Post by JanF »

alan CXA651 wrote: 23 Jul 2021, 09:11 Hi JanF.
I dont have P3D or HF1 , i use FSXA and sometimes Active Sky , lets clear some confusion here with regards to
1. fuel tanks , ENG 1 and 4 tanks hold 425 gals of fuel ENG 2 and 3 have two fuel tanks for each eng , but both tanks equal 425 gals. IE on lt load ALL engs have same amount of fuel of 425 gals each .
2. If an engine quits , it will windmill in the airflow , this causes drag and will slow you down , thats why you have to feather the prop , to stop the windmill and reduce drag on dead engine , but you have to be quick , because you cannot feather if oil pressure drops in the engine , as the dead engines oil is used for feathering its prop.
Did you have any faults in the hanger , or did you not fill the fuel tanks to same ammount , also the engines have got to be trimmed out with same prop RPM/MAN and even then you will get uneven fuel burn depending on state of engine ware and hours , this is why you need constant monitoring of systems , so you can spot problems developing and take actions to prevent it as best you can.
regards Alan. 8)
That is strange since I first didn't feather the prop but during this time I didn't notice any loss of speed. Eventually (but I was not quick) I did feather the props and it did work.
I did not fill the tanks to the same amount didn't think I needed. No mystery that I emptied the tanks.
If I understand you correctly I should fly the plane in such a way that equal amount of fuel remains in the tanks ?

alan CXA651
Senior Master Sergeant
Posts: 2438
Joined: 15 Mar 2016, 08:23

Re: This makes no sense to me

Post by alan CXA651 »

Hi JanF.
You do not need to keep all tanks absolutly the same , as ware and tare on the engines will differ as the hours go by , but if they are close to each other say within 4 to 5 gall , this helps to keep the aircraft trimmed out better , and easier to fly , as well as keeping all the engines running , also if you get a dead engine , use the fuel from the dead engine to transfer this fuel to the other good engines to keep the fuel more or less even in all the tanks .
regards Alan 8)
Image
Image
Image
Image

new reply

Return to “B-17 Flying Fortress”

Who is online

Users browsing this forum: No registered users and 2 guests