Me 110: Tank switch & 1-axis AP

[Redroach]

After my first rather lengthy flight in the Me 110 (140 mins), I'm a bit confused with the tank selection switches. The switch on the front panel to select which fuel tank quantity should be shown, seems to work fine. But the switch on the side panel, where you (presumably) actually switch from tank to tank (Front left, F/R, Back left, B/R) seems to be reacting a bit strange from my pov.
At some point, I've completely drained F/L - red light on the panel went on, the gauge showed empty. All in order so far, so I switched to the next tank - F/R, if I remember correctly. But later, the light for B/R went on, despite if selecting to show F/R on the dial, it seemed to be full. And, actually, I started to lose power, so I presume there could be something the wrong way round. I haven't tracked it piece by piece, but the final situation was: Light on for F/L and B/L, Gauge showing 0 fuel for F/L and B/R, and engines NOT losing power (i.e. tanks actually NOT empty) for B/L and B/R
Can somebody shed light on this? Or could it be declared a bug?

As for the second point, I'd really appreciate it if somebody could give me a short introduction for that shiny 1-axis-'course mode' autopilot in the Me110. I'm not really sure how to use the knobs and switches. After 'testing' around rather randomly, I've settled on a course that fit my desired one quite well, but the read-outs were rather awkward:
-Magnetic Compass showed 68° (Yep, I'm aware of magnetic N vs. geographic N ;) )
-'Daughter' Compass showed 71° (might be irrelevant with respect to the AP)
-upper dial in the AP controls showed 59°
-lower dial in the AP controls showed 55°
So, somewhere 'in the middle', I came home with that, but I'd like to understand it a bit better. It seems to be a neat tool, especially for the long channel transits :)

[W32Blaster]

Brief description for one axis autopilot (directional only)

First Gyro Compass has to be set to the same direction that magnetic compass is showing.
Gyro Compass is the one underneath the big 'DaughterCompass' the one with two bands for course and Libelle (BALL Intsrument) integrated.
Set course with the knob on the right of the instrument.
This has to be corrected every now an then. (i.e. at least every 5 min crosscheck gyro with magnetic)
(I dont know wether the need to correct that often isn´t a bug. I think it´s strange behavior, maby someone knows?!)

Desired Course for One axis autopilot has to be set with two-way-switch on left upper side panel labelled L and R.
Course which is set shows on lower gauge of gyro.

Switch on one axis autopilot with switch right underneath the ReVi, switch position 1
Position 2 is unused in Bf110.

Mismatch of steering course and course set with autopilot is shown by instrument labelled 'Kurs' right under ReVi.

Since Plane tends to roll when autopilot is correcting direction with rudder, keeep plane straight with corresponding aileron input.

Corrcet course for winddrift if wind is present.

Switch of with selectorswitch under ReVi prior to landing or manuevering, since autopilot will try to correct cours otherwise.

For question obout tank selection refer to:
http://forum.1cpublishing.eu/showthread.php?t=22852

[jojovtx]

I believe the fuel tank gauges do not coincide with the fuel tank selector switch. I fly with roughly 40% fuel all the time and that shows as roughly 250 litres in front left and right tanks. However, when my front left tank runs out and I change the selector switch to front right my engines die. I have to set me selector switch to rear left tank in order to draw fuel that the front right tank fuel gauge says I have.

Another issue I have is that my TG does not fire in MP. He will open the hood and track targets with his gun but he will not fire.

[Blackdog_kt]

For the fuel tank selectors, have a look here:
http://forum.1cpublishing.eu/showpost.php?p=298257&postcount=179

For the autopilot, Blaster is mostly correct and as with all gyroscope operate instruments, the gyrocompass needs adjustment every 15 minutes or so, or after violent maneuvers.

I only have two other observations to add. First, the big red "disengage AP" button seems to be a temporary switch: the AP is disengaged when you hold it down, but as soon as you release it the AP snaps back into action. This is probably only for minor corrections to the tune of "oops, i'm slowly drifting into the 88s i'm supposed to be escorting, let's temporarily disengage the AP and maneuver wide of them".

I use keys that i mapped to the "course autopilot next/previous" functions to really turn it off for good.

Second, there's an offset of between 5 to 7 degrees between the master gyrocompass and the desired/commanded heading compass card.

For example, let's say i'm flying a heading of 100 degrees back to base and i want to engage the AP and stretch my legs a bit to relax. I look at the magnetic compass, place the mouse cursor over it and it reads 100 degrees. I then turn the master gyrocompass to 100 degrees.

To make sure the aircraft won't drift once i engage the AP, i also turn the desired/commanded heading compass card (what i want the AP to maintain) to 100 degrees.

The AP works on a correlation between these two, it completely ignores both the magnetic compass (right hand side of the cockpit) and the magnetic repeater compass and its course finder (the compass rose with the airplane silhouette in the middle disc).

So, the way to do it is:
1) Read magnetic heading (add the magnetic deviation if you want to be really precise).
2) Input magnetic heading into master gyrocompass
3) Input the same heading into the desired heading compass
4) Engage the AP.

At this point the aircraft should maybe drift left and right a bit until the gyroscopes stabilize, but it should for the most part stabilize with all relevant instruments (magnetic compass and repeater, master gyrocompass and desired/commanded heading compass card) indicating 100 degrees.

Well, it doesn't. It actually banks the aircraft until it's 5-7 degrees off each and every time. Not a big deal because it's always the same amount roughly so you can account for it when setting it (i just give it a wrong desired heading by 5-7 degrees the opposite way so it evens out), i just don't know if this is realistic behaviour or a bug.

In the end, if for example i want to go north the instrument face looks like this:
------N--
----N----

When it should look like this:
----N----
----N----

I don't know if this can be zeroed out by maneuvering "against" the AP, as it's perfectly possible to use the controls while the AP it's doing its thing.

[Redroach]

Thank you, I've mostly found out things by myself in the meantime, but still, useful info!
Regarding that 5-7 deg. offset: It's actually 10.11deg (west), as was stated in some patch notes by luthier. I cross-checked this value with an US geomagnetic Survey site and it's fairly accurate for 1940 england.
This means that, in order to account for magnetic declination (offset between geomagnetic north, which is what the mag. compass shows, and geographic north, which is used in maps), you have to set your gyro compass (as well as the daughter compass, if you want it to show true north) 10 deg. forward with respect to the magnetic compass - then, the 1-a-AP works correctly, at least for me.

Regarding fuel tanks: The switch to the right and the switch + gauge + lights on the front panel are not actually connected. The actual tank switch is to the right, of course, but you can independently check your fuel tank contents with the front switch. But both switches are not correctly correlated; see my first post - I believe B/R and B/L are the wrong way around on the (actual) tank selector switch.

[335th_GRAthos]

Thanks guys,

excellent explanation on how to setup the course automatic on the ME110 !

...and I needed it badly today.

~S~