German compass navigation: degree per second turn indicator?

[Nealius]

I've been having trouble with compass navigation in the German warbirds due to the compass freezing up during turns. I discovered this is realistic and that pilots would turn x-seconds at a known rate before rolling level and checking the compass. In this video (timestamped) it's mentioned that the artificial horizon contains a rate-of-turn indicator in order to accomplish this. 

However, this isn't mentioned in the ED manuals or Chuck's guides for the German warbirds. Does anyone know how to read/use this rate-of-turn indicator in order to properly navigate with the compass? The video author also did not know how the instrument itself is calibrated.

 

[razo+r]

I'm going to guess it's the vertical needle on the artificial horizon. I suppose when the vertical edges of the white markings meet, you are flying a standard rate turn (or maybe another rate) . 

To verify that, you could enable the cockpit bar and count if you are doing a standard rate turn when you lined the markings up. If that's not the case, you would need to figure the rate out yourself, as I currently can't find any infos on that. 

Edited February 25 by razo+r

[Nealius]

I did some testing.

The vertical needle appears to function more like a bank angle indicator than a rate indicator. One block width is roughly equivalent to 10 degrees of bank, regardless of airspeed/altitude. But this is just a guesstimation because there's no gradations marked with which to be sure I'm actually two block widths and not 1.5 block widths.

At 4km, 400kph, 20deg bank my turn rate was approx. 1.6deg/s. White block of the needle was approx. two block widths away from the center block.

At 4km, 400kph, 30deg bank my turn rate was approx. 2.4deg/s. White block of the needle was approx. three block widths away from the center block.

So far no luck trying to figure out how to roll out on a precise desired heading without zig-zagging endlessly to sweeten my course after wings level. Really missing the gyro compass of the Allied warbirds.

Edited March 2 by Nealius

[razo+r]

In that case you might aswell go with a general rule of thumb for a standard rate:

Angle of Bank for standard turn rate = ( TAS (in kts) / 10 ) + 7 [Or in case of metric, it would be ( TAS in KPH / 20 ) + 7]

Now I know this is going to need a lot of conversions in order to do this and it's not really usefull this way, but if you simplify it, it should get you somewhere in the ballpark for a standard rate. And a standard rate is 3 deg/s.

To get KTS, just divide kph by 2 and add a tiny bit on top of it.

To get TAS, take your IAS and add 2% per 1000ft. 

Example: Lets take your 4km 400kph as an example.

4000m are 13'000ft -> 26%.

400kph are a bit more than 200kts. 26% of 200 kts is a bit over 50. So it would be ( 260 / 10 ) + 7 = 34

You got a little below a standard rate with 30 degrees bank, so 34, round up to 35, should put you quite well on a standard rate.

The lower you are, or the more standard the atmospheric conditions are, the less you have to fiddle around with TAS to IAS. But like I said, with all these conversions, it might not be the easiest thing to do on the fly. You might be better of simply taking a reference point by looking out the window, turn towards it, check the compass and correct.