Saturday, July 8, 2017

DCS Bf-109 K4 - How to Take Off

Topic for today: taking off in the Bf 109 K-4 Kurfürst. This is from a custom-made scenario played in DCS World Alpha, with the Normandy map. The take offs shown in this post are from the Carpiquet airfield.

In a clear day like this and in a clean configuration, we fly.
The K, as many of the other variants, had a powerful engine (a 1,800-hp DB 605 D), a narrow landing gear plus a small tailfin and rudder. This particular combo may put you virtual pilots in a pickle during take offs. I know it did for me.

According to the DCS manual, you should set up your trim at +1, set flaps to 20 degrees, give it throttle to 1.35 ATA and then -in an understatement of colossal proportions- "proceed with take off".

In some airstrips across Europe, mostly the ones where German allies got acquainted with their new Bf 109s, there was a so-called "Messerschmitt corner" where Bf 109s would be literally driven to by rookie pilots during failed take offs. The corner was beyond the end of the runway, to the left of the direction of the take off.

If you find yourself a dweller of the Messerschmitt corner, you should read this post.

I take off with the Governor Automation Switch in the automatic position. You can set it to manual, but the automatic position is able to deal with the pitch changes during of take off.

That little black switch below the throttle assembly is the Governor Automation. Set to "Auto" (down) right now.

Pitch trim to +1. The pitch trim is set with one of the big wheels on the left.

The other wheel shown above is for the flaps setting. For take offs I set it to 20 degrees, as stated in the manual.

I then step on the wheel brakes (the red triangular symbols in the controls indicator shown in the bottom left), and I increase the throttle to 1.35 ATA or so. This has to be done not so abruptly to avoid tipping and hurting the nose of the Bf 109.

I let the brakes go and the aircraft starts moving, slowly veering left. I counter this tendency with the right wheel brake. See the red triangle in the control surfaces indicator (bottom left corner).

Critical moment. At around 100 Km/h, there will be enough airflow to feed the rudder (i.e. making it an effective control surface). There is a sound queue for that, a small shudder sound. Kudos to DCS for that important detail.

As soon as the rudder becomes effective, use it. Otherwise the aircraft will roll left as shown here.

The first use of the rudder should be a kick on the right pedal, then use both pedals to correct any tendency to roll right or left. The tail wheel comes up shortly after that. I don't do anything to push the tail up, but some people do. 

Fun fact: the tail section of most of the K's was made of wood, but as it turned out this material made the tail heavier than the ones made of aluminum.

And then I am airborne. What a beautiful day to fly, fellows!

One important part I didn't mention is that if everything goes right, there is no need to adjust the throttle from the initial 1.35 ATA manifold pressure. I suppose this will depend on the configuration.

And finally, I made a short video to show these take offs. A link is provided below. This video contains some graphic scenes of bad pilotage while I was learning. The last take off is the one that you should see.



Marco Diaz said...

Nice, the german planes are more difficult to take off and hard to land. It's something that I don't get why they have such a problems in design that in the end cost them a lot of planes, just in operational losses.

JC said...

Relatively speaking (i.e. compared to today) maybe a fighter aircraft was cheaper back then? I agree with you, but also one has to recognize that many of the physical cues one has in a real aircraft are absent in the virtual world.


Marco Diaz said...

Yeah but also in comparison with UK forces of the time, the operational lost ratio was too high. Perhaps it come from the experten mentality, tough planes make tough pilots?

JC said...

Well, there is also this "if it is not hard it's not realistic" hardcore design that DCS and fans gloat about. The lack of sensory feedback also helps to make it harder. But I doubt that in real life an aircraft made in such quantities would be a nightmare to handle.