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triflyman View Drop Down
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    Posted: 31 Dec 2015 at 8:36pm
Have not been able to make the fuel cross-feeds work.  I have the new SP and am trying this on both the 21 & 33.

Found a post from last year on this subject from sevenflyer that tells how it should work but engine dies that I trying to cross-feed to as soon as it's tank runs out of fuel or if (as the post says) I put the Center Wing Aux lever down.  Have also tried cross-feed before any tank is empty but nothing from the feeding tank goes to the receiving engine.

Just Flight has been no help on this...just saying no one else is having a problem and I need to read the manual.

Any one been able to get it to work and if yes what are the settings you use.

Thanks
Garry
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Mustang1977 View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Mustang1977 Quote  Post ReplyReply Direct Link To This Post Posted: 23 Feb 2017 at 7:09pm
Hey hello,

Same suspiction here. Did my 1st Testflight today with the 32. The Balancing is not the problem, but I wanted to use only the 2 inner Tanks because the outhers running dry.

Tried several combinations with the Crossfeed-Levers, but the outher engines don't want to take fuel from the inner tanks Thumbs Down

Will make further tests, but it doesn't looking good Ermm
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Mustang1977 Quote  Post ReplyReply Direct Link To This Post Posted: 23 Feb 2017 at 9:47pm
Hello again,

After further investigation I've found an error in the Fuel-Tank Configuration.

First, have a look at this scheme I've created. It represents the exact Fueltank Config as show up in the "Fuel & Payload" Dialog:



As you can see, the Center and the Left Tank positions must be changed.

I'am not able to correct this via the aircraft.cfg because the Tanks Center 1-3, Left Main and Right Main have the same Lateral Positions. I think the error have to be corrected in the VC itself (Model or Gauge-Files).

But I'am not sure if this error is the cause of the Fuel-Crossfeedsystem is not working.

Last but not Least: As you can see in the Wikipedia, the Total amount of fuel for the 32 is not correct. Fuealquantitiy in aircraft.cfg: 22 058 GAL - Real (Wikipedia): 23 313 GAL. But this can simple corrected in the aircraft.cfg.

I will contact the Support in this matter, maybe they can help Smile


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triflyman View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote triflyman Quote  Post ReplyReply Direct Link To This Post Posted: 23 Feb 2017 at 10:08pm
Originally posted by Mustang1977 Mustang1977 wrote:

Hello again,

After further investigation I've found an error in the Fuel-Tank Configuration.

First, have a look at this scheme I've created. It represents the exact Fueltank Config as show up in the "Fuel & Payload" Dialog:



As you can see, the Center and the Left Tank positions must be changed.

I'am not able to correct this via the aircraft.cfg because the Tanks Center 1-3, Left Main and Right Main have the same Lateral Positions. I think the error have to be corrected in the VC itself (Model or Gauge-Files).

But I'am not sure if this error is the cause of the Fuel-Crossfeedsystem is not working.

Last but not Least: As you can see in the Wikipedia, the Total amount of fuel for the 32 is not correct. Fuealquantitiy in aircraft.cfg: 22 058 GAL - Real (Wikipedia): 23 313 GAL. But this can simple corrected in the aircraft.cfg.

I will contact the Support in this matter, maybe they can help Smile



Thanks Mustang.  After my first lie from support (that no one else was reporting this) I sent them copies of reports from their own forum proving that several people did report the problem.  They never replied.  Please let me know if they respond to your inquiry.

For over the last year there is supposed to be a new "fix" for all the things wrong with the model (it's a lot)...but has still not come.  Although I have a past relationship with the real DC-8's...and would love to be able to fly her properly, I finally gave up and asked for my money back...which they gave me.  I have not flown her for about a year...just to many issues.  When they refunded my money, I asked when the fix was coming and they only said "not tell after February", so we'll just have to wait.  Meanwhile I just enjoy flying the new A2A Connie and the new version of the C-47 V3 that just hit...now if we can get the PMDG DC-6B for FSX almost all will be good until JF releases the update.
Garry
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Mustang1977 Quote  Post ReplyReply Direct Link To This Post Posted: 23 Feb 2017 at 10:25pm
Hey,

No problem man, I will write here if (or if not) they reply.

If you are looking for a good airplane similar to the DC-8 maybe the Captain Sim 707 is for you. This is one of my favorite planes and she is a bit faster than then DC-8 (Mach 0.92 is possible).

And, the Fuelsystem is free of errors and work as it should! Thumbs Up 

The only (bigger) bug she has is a gauge that is not working correctly under P3D v3 (it has to be disabled).
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Post Options Post Options   Thanks (0) Thanks(0)   Quote triflyman Quote  Post ReplyReply Direct Link To This Post Posted: 23 Feb 2017 at 10:33pm
Have that and it is great...flown it quite a bit but it's just not a DC-8.  Interesting that about a year ago I was flying KJFK to Europe (don't remember which airport) in the DC-8 and since I use CalClassic Scenery and AI's there was a 707 flying just off my right wing about a mile away at the same altitude.  I had also previously noticed the 707 was slightly faster but with this CalClassic AI I was slowly going by her.
Garry
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Mustang1977 Quote  Post ReplyReply Direct Link To This Post Posted: 24 Feb 2017 at 12:07pm
Nice!

So, here is the answer from the JF-Support:

Hi Matthias

They are still working on updates for the DC8 products so I have passed your comments on to them to see what they say

regards

Martin Wright

Okay, then he have to wait. I'am sure the DC-8 Bugs are not the only things they have to be worked on.

In the meantime, I have made a little "fix" for the crossfeed-problem.

Simply adjusted the Fuel-Levels from the inner- and outer tanks so they are balanced now. Bevor the fix the outer tanks had a combined amount of 4.518 GAL, the inner 4.435. I added the missing 83 GALs to the inner (wrong) left which has now 2672 GALs and the Center 2. Both sides are balanced now with 4.518 GALs.

Furthermore I've corrected the Total Quantity from 22.058 to 23.393 GALs. Simply added the missing fuel to the Center3 (middle). And of course I have subtracted the additional 83 GALs, so a total amount of 23.393 Gallons are guaranteed.

If you want to use this fix unless an official service pack come out, simpliy copy and paste these section in the aircraft.cfg below [fuel] (delete the old entries first)

//Longitudinal (feet), Lateral (feet), Vertical (feet), Usable(gallons), Unusable (gallons)
//DC-8-32   155,797 lbs, 23,393 gals @ 6.8 #/Gal
Center1=7, 0, 0, 2976, 0    ;Right
Center2=7, 0, 0, 2672, 0    ;Center2
Center3=5, 0, 0, 5321, 0    ;Center Wing Aux
LeftMain=7, 0, 0, 2672, 0   ;Left
RightMain=7, 0, 0, 2976, 0  ;Right
LeftTip=5, -24, 0, 1542, 0  ;Left Tip
LeftAux=5, -20, 0, 1846, 0  :Left Aux
RightAux=5, 20, 0, 1846, 0  ;Right Aux
RightTip=5,  24, 0, 1542, 0 ;Right Tip

This fix can also used for the 42 but NOT FOR THE 10, 12, and 21 - they have different (lower) fuel levels which I haven't yet controlled.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote triflyman Quote  Post ReplyReply Direct Link To This Post Posted: 24 Feb 2017 at 8:30pm
Thanks Matthias...I'll hold on to this since I'm not currently flying the DC-8 in case the revision doesn't address this issue.
Garry
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Mustang1977 Quote  Post ReplyReply Direct Link To This Post Posted: 24 Feb 2017 at 9:06pm
Good evening,

How you like it! The question is, how long we have to wait for a new Service Pack Wink

New insights! And of course, I like to share these with you. After several tests I can say that it is not the crossfeed-system itself - it is the Tank-Selection-System. This were and is always a problem in JF-planes Thumbs Down

This is only for the 32 and 42

So, here we go: As you start up the DC-8-32 normally (and as shown in the tutorial flight) all seems to be working fine. Initially, the engines take fuel from the Center3 (Middle) Tank. Ok, why worry, lets take off!

Alright, the Center3 Tank runs dry and you are loosing ALL 4 ENGINES while airborne! This was happends to me - twice I think. So - PANIC! STRG + E - and success! All 4 Engines running again.

And this is the solution for the problem: STRG + E. This command triggers the "All Tanks" Selection. I have made onground tests with the Caravan-Tankselection-Gauge. Never touch it, only hovering over with the mouse - it tells you which tank the aircraft is being used.

With the "normal" start without STRG+E it shows always the Center Tank at the beginning. It does not matter what you are doing with the Tank-Levers: The engines will ALWAYS take fuel first from the Center3 til it's empty. Then you have a problem.

But if you start the engines at the beginning on ground with STRG+E you will have no problems in the air and NO SURPRISES! You never have to touch the Tank-Levers during the whole flight - you only have to monitor the Fuel-Gauges. The engines take fuel first from the outher Tips, then the Aux-Center2 and then the Left/Right. So you are able to use every drop of fuel without the danger to kill one (or more) engines.

I use this config after Enginestart on ground before flight:



After that I never have to touch anythink here again, only monitor the fuel-levels. I think this is a good solution for this problem - I will use it up to the SP's will released (or not xD ).

 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Martyn Quote  Post ReplyReply Direct Link To This Post Posted: 13 Mar 2017 at 9:38am
Thanks for reporting these issues. They've been logged and the development team are looking into them now.

Thanks
Martyn


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Post Options Post Options   Thanks (0) Thanks(0)   Quote Hangar200 Quote  Post ReplyReply Direct Link To This Post Posted: 30 Apr 2017 at 5:09pm
Originally posted by Mustang1977 Mustang1977 wrote:



First, have a look at this scheme I've created. It represents the exact Fueltank Config as show up in the "Fuel & Payload" Dialog:

Thank You! Thumbs Up

  I had figured this out a while ago and listed in on a "yellow sticky"…and then somewhere, somehow, sometime, lost the "yellow sticky".Unhappy
R/ Hangar 200
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Mustang1977 Quote  Post ReplyReply Direct Link To This Post Posted: 30 Apr 2017 at 9:14pm

No problem, but this scheme is out of date because of the last Update Wink
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Hangar200 Quote  Post ReplyReply Direct Link To This Post Posted: 30 Apr 2017 at 9:31pm
<sigh>…time to break out the "yellow stickies" again.Wink
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Mustang1977 Quote  Post ReplyReply Direct Link To This Post Posted: 04 Jul 2017 at 9:31am
Hey people,

Now I've got the time to feel the updated DC-8 "on the tooth".

Better than before, no question - BUT - I'am not able to use the Center Tank Fuel (Center3 with 4152 Gal).

Any suggestions? I've tried several combinations with the fuel levers and Boost Pump Switches.

EDIT 05.07.2016: Ok, at the last flight I was able to "pump" fuel from the Center3 to the Center Tank (2nd from the left) - the amount rises? wtf? - all Crossfeed Levers/Valves where open.

Furthermore, when I close the left CF-Valve the same effect at the Ext2 (2nd from the right) - VERY STRANGE. This cannot be a useful fuel strategy Exclamation With this the tanks became completely UNBALANCED.

I've also tested what happend if one of the tanks becomes empty but all Crossfeed Valves/Levers are open - the engine turns off -.-.

Now I've set the Center3 Tank amount to 1 in the aircraft.cfg and divided the amount through 8 and add it to the rest of the tanks. Now it is possible to make an "balanced flight".

This should be corrected in one of the further Updates.
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