Fuel&Engine questions

[Artur]

1. Have noticed that cannot start engines no 1&4 if there is no fuel in respective tanks, even cross feed valves are opened - is it normal ?
2. Fuel consumption for engine 3 and 4 are always higher than for 1 and 2 (?)
At the end of flight, fuel imbalance is considerable, but FE does not care about it
3. In very cold conditions ( -30C outside ) it is not possible to start engines unless "auto start" function is used.
Oil dilution done prior last flight does not help.
4. Fuel consumption given in manual for FL210 is 525 lbs/h, actual consumption is Ä…prox. 700 lbs/h ( rpm set for 2120, torque 144 PSI, free air temp. - 43C )
Why so big discrepancy ?
5. Is it possible to have climb data for FL220/230 and 240 ? ( manual page 137 )

[alan CXA651]

Hi.
1/ Are you doing the engineers job or are you letting him take full control .
Also i think the tanks need fuel in the respective engines tanks , and on fuel transfer it just ballencies the fuel tanks , if tanks 1&4 are empty , then you need to transfer fuel from the other tanks before trying to start engines , as i believe each engine fuel feed comes from their respective tanks.
2/ fuel consumption will be different for each engine , as they wear differently , you have to play with the throttles to balance power/fuel usage , also would depend if you had crosswinds , as this would also effect the power/fuel usage as in a real aircraft.
3/ these are extreme cold conditons , and might require oil change prior to starting , in the real world at these extreme temps , they would run the engines every 30 min to 1 hr to keep them semi warm.
4/ these figures are only guide examples and your engine wear will determine actual usage.
5/ i find my aircraft even at full load gets a good climb speed at 500ft min rate of climb , with 35mp 23 rpm , but i have not as yet gone to 25000ft , highest i have gone at full weight is 20000ft , at full weight you would need a step climb method to get to max alt.
regards alan.

[Artur]

We are talking about situation where engines are brand new, and systems are managed by FE

3. Maybe A2A can simulate some engine pre-heat system or cart ? Would be nice
4. We talk about new engines, and i feel discrepancy is too big
5. I do my fuel planner in Excel, so those figures i need for that purpose, although i have doubts about accuracy manual data/flight

[alan CXA651]

Hi.
Even new engines will use fuel and power at different rates in the real world , and in this connie , as A2A designed it to mimic real world conditions , as no two engines will be the same.
regards alan.

[LostSoul]

Regarding the capability of engines running on different tanks:

The fuel system is very simple. It basically consists of 4 main lines from tank to engine with respective aux. electric pumps and crossfeed valves inerconnecting all 4 fuel lines. So as a result as long as there is fuel in ONE tank and all crossfeeds are open and the aux. pump of the respective tank is running, there is fuel supply granted to all engines.

In this Connie however the engines behave very strange. If you empty a tank with the engine runnning (all crossfeeds open and pumps on), the respective engine rpm drops to a very low state and remains there, the oilpressure warning lights come on almost instantly, the FUEL PRESSURE however remains in NORMAL RANGE (which is correct)! Adding fuel again in the emptied tank will result in the engine recovering to normal running (you might need to add some power for a moment). There is something wrong in that behaviour. There is no reason for the engine RPM to drop as long as the Fuel Pressure for the respective engine remains in nomal range.

[CAPFlyer]

1) Why are you trying to do this? This is an incorrect fuel configuration and creates multiple problems within the fuel system by allowing air into feed lines and making it where the engine pump will be unable to maintain pressure because of it.

2) How much higher? If it's more than 100 lbs/hr difference, then something is configured wrong or you need to do a re-install. Don't know why the FE wouldn't balance however unless you have him turned off because we've tested him extensively and never had an issue with him balancing as long as you're not interfering with his operation.

3) It takes technique and patience, but it's not impossible. Search the main Connie forum as there are several threads on cold starting the engines and tricks people have found for starting in extreme cold. The biggest thing is you can much more easily over-prime the engine in that extreme cold, so most likely you're flooding the engine and that's why they won't start.

4) You're either still in Auto Rich instead of Cruise Lean or you have a bugged install and need to re-install.

5) The charts included are the complete charts from the original manual. If you notice on the chart, those last 3000 feet of cruise altitudes give very little performance advantage over lower altitudes because the increase in fuel consumption is significantly more than the increase in speed achieved. As such, while listed, they're not considered "normal" cruising altitudes and thus any climb is done after initial cruise is established and you simply set climb power and climb to those altitudes or use a cruise climb to get there, so there's no real way to chart them because there are too many variables to getting there.

[Artur]

3. I do not flood the engines ( no hangar report about it ) - i can try half an hour and no success...
4. I'm in cruise lean ( as said, engines are maintained by FE ) - still see no reason and explanation for such discrepancy. Can u check fuel consumption during one of your flight ?
5. Thanks for clarification - this question is closed.

[alan CXA651]

Hi Artur.
Look at the connie 12 min introduction video , where scott explains about the engines being different from each other .
regards alan.

[Gypsy Baron]

Just a clarification on a statement made somewhere up-thread. If a fuel tank is EMPTY,
you can not transfer fuel from another tank to the empty tank. There is no facility
to do this, unlike the B-17G where that is possible.

All you can do is connect the engine with an empty tank to one with fuel via the
use of the X-Feed valves and Tank Cut-Off valves with the aux fuel pump ON for the
tank that is feeding the x-feed manifold.

Paul

[LostSoul]

Just a clarification on a statement made somewhere up-thread. If a fuel tank is EMPTY,
you can not transfer fuel from another tank to the empty tank. There is no facility
to do this, unlike the B-17G where that is possible.

All you can do is connect the engine with an empty tank to one with fuel via the
use of the X-Feed valves and Tank Cut-Off valves with the aux fuel pump ON for the
tank that is feeding the x-feed manifold.

I fully agree. Nevertheless it IS possible to run ALL FOUR engines one ONE single tank's fuel. Therefore - to go back to the initial question - it must also be possible to start all engines on ONE single tank, as long as the appropriate setting for fuel and crossfeed cocks is done. Whether this makes sense or not is beyond this subject. It's just about the technical possibilities.

[Artur]

Would it be possible for someone from A2A to clear question about big discrepancy with fuel burn ?
It is essential for more accurate fuel planning.

[CAPFlyer]

Have you tried re-installing the Connie yet as I suggested? You also still haven't answered my question about your issue #2 in the original post as to how much higher #3 and #4 are than #1 and #2, so we have no more basis to see what's going on.

There's not really much "someone from A2A" can do with your questions as the information given doesn't jive with what we saw in the BETA tests and what other users have seen since release to confirm our testing. I can only surmise that you've got something in your setup external to the Connie causing the problem because there's no reason to have such high fuel consumption if you've got everything set exactly to the charts.

[Artur]

Hi,

So i understand that your Connie burns aprox. 2100 lbs/h at FL210 with parameters set as given in manual, right ?

I have reinstalled my Connie 3 times, every time with 'administrator rights', every time installation was smooth and successful.
Apart of fuel burn discrepancy and problematic engine start during winter condition, everything works normal.
What can be wrong in my set up to cause higher fuel consumption ?
As said before - engines are controlled by FE, and are set for 'cruise lean'
What else can be on 'my side' ?

One thing more i have noticed - engines fuel burn is even higher ( aprox.800 lbs/h ) until FE set pressurization for actual cruise level.
As long as he announce 'pressurization set', fuel burn drops by aprox.100 lbs to level of aprox. 700 lbs/h.

[CAPFlyer]

To be honest, I don't know what within the Connie itself could cause that much of a discrepancy. Are you sure that all the realism settings in FS are correct and you don't any any addon programs operating that might be "adjusting" your sim's flight dynamics?

[Artur]

I'm sure.
I keep my sim simple and clean