Always full nose trim down?

[Tree_Beard]

I find that after I take off in the 109, putting the nose trim down all the way (+1.5) makes it much easier to fly level and control the plane in general. I leave trim like this for the duration of the mission, until I need to land. 

Am I putting myself at a combat disadvantage by doing that? Or is that how you are supposed to fly the plane? 

[motoadve]

On 8/5/2023 at 10:13 AM, Tree_Beard said:

I find that after I take off in the 109, putting the nose trim down all the way (+1.5) makes it much easier to fly level and control the plane in general. I leave trim like this for the duration of the mission, until I need to land. 

Am I putting myself at a combat disadvantage by doing that? Or is that how you are supposed to fly the plane? 

I doubt any Aircraft manufacturer will make a trim like this, has to be a bug, I was thinking just about it yesterday while flying the 109 inside the clouds for quite some time, it would have been very unsafe to fly in IMC conditions fighting the pitch all the time.

[grafspee]

At this stage K-4 at speeds 500kph has tremendous problem in pulling out of dive, not mention at higher speeds. Being able to trim further nose down would be straight forward lethal. Topic was discussed many times, and ED view on this topic is rock solid since i remember.

Edited August 8, 2023 by grafspee

[Nealius]

I set nose down trim max down and keep it there for all regimes of flight, at least at low altitudes. I wish I could trim down more because it tends to climb a lot, and the takeoff is spicy. 

[Art-J]

7 hours ago, motoadve said:

I doubt any Aircraft manufacturer will make a trim like this, has to be a bug, I was thinking just about it yesterday while flying the 109 inside the clouds for quite some time, it would have been very unsafe to fly in IMC conditions fighting the pitch all the time.

Apparently that's how wartime Gs were rigged. Our K has the same trim curves implemented in its flight model as a compromise, 'cause similar data for K is not available, while both airframes are similar enough. So, unless someone discovers actual trim charts for K, that's the intended implementation for now. 

More on the subject here, and in the linked discussion thread:

 

[grafspee]

7 hours ago, Nealius said:

I set nose down trim max down and keep it there for all regimes of flight, at least at low altitudes. I wish I could trim down more because it tends to climb a lot, and the takeoff is spicy. 

I trim nose up when doing gun strafing, with trim all way nose down, pulling out isn't as easy as in allied planes.

Take off with flaps employed is quite easy. 

[IIIJG52_Otto_]

@Art-J and @motoadve I think that we cleared what was the true stabilizer trim configuration of the Bf-109G in cruise flight, in our interview to Flugmuseum Messerschmitt test pilot Volker Bau in 2016. The neutral trim modeling of the K4 in game is completely broken compared what Volker Bau said. ..and yes it is awesome, but it still broken from 2015.

Edited August 15, 2023 by IIIJG52_Otto_

[Nealius]

On 8/9/2023 at 6:46 AM, grafspee said:

Take off with flaps employed is quite easy.

Recently discovered that though I had a fuel tank too. Not sure which helped more haha.

[motoadve]

2 hours ago, IIIJG52_Otto_ said:

@Art-J and @motoadve I think that we cleared what was the true stabilizer trim configuration of the Bf-109G in cruise flight, in our interview to Flugmuseum Messerschmitt test pilot Volker Bau in 2016. The neutral trim modeling of the K4 in game is completely broken compared what Volker Bau said. ..and yes it is awesome, but it still broken from 2015.

 

Thanks for showing that, I cant imagine a plane being manufactured with not enough trim either down or up trim.

Even in cruise at 1.0 ATA you cannot use 0 trim, it will climb and you need , pressure on the stick at that power setting you need to almost all the way forward on the trim close to 2.

I fly real planes, have flown from a Tiger Moth to a PC12 , cannot imagine flying a plane with the trim like that, would be a handful and dangerous in many situations, IMC for starters. 

Plane flies great and feels great except for the trim.

In the interview the pilot mention the radiators, he used them manually, how do they work in game? I tried the right and left lever for the manual radiator and they do nothing.

[kablamoman]

@motoadve

There was quite a bit of interesting back-and-forth with Yo-Yo in this thread that may shed some light on what's going on:

 

[peachmonkey]

I tried flying K4 using my VKB gun fighter pro and it was a very unpleasant experience with 100% fuel, it gets a bit better with 50% fuel but still very annoying to keep forward pressure on the stick at all times.

Not for bragging purposes, but getting an FFB joystick 'solved' this inaccuracy. With RHINO base I can use the 'hardware trim' function to over-ride the center and move the stick spring center forward...

so there's a solution, but it's expensive ($800) and the wait time is .. forever.. (1 year).

 

[Art-J]

23 hours ago, IIIJG52_Otto_ said:

@Art-J and @motoadve I think that we cleared what was the true stabilizer trim configuration of the Bf-109G in cruise flight, in our interview to Flugmuseum Messerschmitt test pilot Volker Bau in 2016. The neutral trim modeling of the K4 in game is completely broken compared what Volker Bau said. ..and yes it is awesome, but it still broken from 2015.

The only thing it proves is that sources contradict each other unfortunately, and since they all can't be correct at the same time, something needs to be prioritized/chosen over the other.

I don't doubt that the Red 7 Mr Bau flew is rigged the way he describes in the interview, but when choosing between evidence of a modern restored airframe on one hand (originating from HA-1112 at that) and WWII period test flight data on the other hand, I know I'd always choose historic data, even if incomplete as in this very case. Even in that thread kablamoman linked to, Rel4y used some wartime spare parts catalog and other reports to question the current implementation, so we can discuss if Yo-Yo's extrapolation approach was optimal.

We've had the same discussion with Mosquito module, where cockpit videos of restored plane showed different cruise trim setting than the one required in the sim. Turns out, the sim implementation is also based on factory documentation from the period, so it was chosen over what current, restored airplane shows.

[IIIJG52_Otto_]

2 hours ago, Art-J said:

We've had the same discussion with Mosquito module, where cockpit videos of restored plane showed different cruise trim setting than the one required in the sim. Turns out, the sim implementation is also based on factory documentation from the period, so it was chosen over what current, restored airplane shows.

After 20 years working as aircraft mechanic, and with more than 25 hours fliying as pilot student, i think that probably we could have the same trim configuration problem in all warbirds modelled in DCS due to two basic things.

1/ Trimmers of an aircraft are not an exact science. Wind direction , speed, air density,  etc change the aircraft behavior in same level flight condition in the real world..
Even the real pilots don't pay great attention to trimmers indicators because in flight they usually trimming the aircraft by feeling or flight attitude. But trim position must be checked in T.O. and landing checklists.

2/ the weight and balance and CoG position of the aircraft change if we change the load of the aircraft, via fuel consumption, dropping bombs, etc

As we are doing in the real planes, the developers should model the neutral trim position for cruise flight with "typical" fuel and ammunition load. But after that the cruise flight trim position in the cockpit, will NOT be the same with the aircraft in full weapons and fuel load. 
Finally i'm not sure if developers of DCS are doing this in the Flight Models.  As you must know DCS born for modern jet combat simulation, and many of these modern jet fighters have fly-by-wire control computers who trimming the aircraft automatically for a take off weight, .. so manual neutral trim was not needed, as we need today with DCS WWII aircrafts.

This mean that many virtual pilots accustomed to jet fighters auto-trim, will feel rare behavior of the warbirds if the neutral trim is not properly modelled, for a typical take off weight and cruise speed.

[Nealius]

22 minutes ago, IIIJG52_Otto_ said:

Finally i'm not sure if developers of DCS are doing this in the Flight Models.  As you must know DCS born for modern jet combat simulation, and many of these modern jet fighters have fly-by-wire control computers who trimming the aircraft automatically for a take off weight, .. so manual neutral trim was not needed, as we need today with DCS WWII aircrafts.

ED's first FBW module (Hornet) was released years after the Dora, Mustang, K-4, F-86, Mig-15, A-10C, F-5E, and L-39. I can tell you from first hand experience that your point number 2/ is modeled in every module. Trimming the A-10C as you're getting gas from a KC-135 is not easy. Forgetting to switch wing tanks in the Mustang will make one wing heavier. Trying to fight with the aux tank still full in the Spit is a nightmare.

Point 1/ could probably be tested with the Mosquito since it has very nice markings to note trim position.

Edited August 16, 2023 by Nealius

[IIIJG52_Otto_]

2 hours ago, Nealius said:

ED's first FBW module (Hornet) was released years after the Dora

As far i know DCSW is a E.D. development of the LOMAC released in 2003 with Su-25, Su-27, Su-33, Mig-29A, Mig-29C, F-15C, and A-10A some of them with computer aid for flight controls.

[grafspee]

What would happen if we could trim K-4 further nose down? As things are now K-4 has significant problems with pulling high G at high speeds, by having more nose down trim you could set up the plane that way, that you could not pull any G at all.

[IIIJG52_Otto_]

25 minutes ago, grafspee said:

What would happen if we could trim K-4 further nose down? As things are now K-4 has significant problems with pulling high G at high speeds, by having more nose down trim you could set up the plane that way, that you could not pull any G at all.

That wouldn't happen if you were flying with the correct neutral trim ( aircraft leveled, straight, ball centered at cruise speed, hands-off and zero degrees trim position), because you would have the control stick in the center and whole stick travel for pulling all G´s that you want. 
Even you could trim -1º (nose-up) prior to engage in a dogfight like did Lt. Kurt Bühligen (112 victories) flying the Bf-109 G6. As we can read in the book P-47 vs BF-109G/K by Martin Bowman.
 

Edited August 16, 2023 by IIIJG52_Otto_

[IIIJG52_Otto_]

On 8/15/2023 at 3:12 PM, motoadve said:

In the interview the pilot mention the radiators, he used them manually, how do they work in game? I tried the right and left lever for the manual radiator and they do nothing.

in game the K4 radiator flaps work perfectly synchronized in both wings, but in real live the Bf-109G hydraulic actuators of the radiator flaps have a little bit opening retard, comparing one wing, with the other. this cause a roll movements when open and close automatically.  Volker Bau explained that he open the radiator flaps in manual mode because the unexpected automatic aperture of the flaps on take-off run could cause a unwanted bank in the worst time. As far i know, In the full open and full close positions of the both wings radiator flaps they don't affect to trim of the aircraft.

null

[Nealius]

8 hours ago, IIIJG52_Otto_ said:

As far i know DCSW is a E.D. development of the LOMAC released in 2003 with Su-25, Su-27, Su-33, Mig-29A, Mig-29C, F-15C, and A-10A some of them with computer aid for flight controls.

Only the Su-27 and -33 have FBW systems (29 as well?). The rest do not. The idea that the sim started with jets and thus trim in general may not be modeled is not logical--also, as already mentioned requring trim in response to CG changes etc. as in your point 2/ is modeled. I recommend flying DCS more, and more modules, before making  assumptions.

Edited August 17, 2023 by Nealius

[IIIJG52_Otto_]

On 8/16/2023 at 3:52 PM, Nealius said:

ED's first FBW module (Hornet) was released years after the Dora, Mustang

 

On 8/16/2023 at 7:11 PM, IIIJG52_Otto_ said:

As far i know DCSW is a E.D. development of the LOMAC released in 2003 with Su-25, Su-27, Su-33, Mig-29A, Mig-29C, F-15C, and A-10A some of them with computer aid for flight controls.

 

On 8/17/2023 at 3:14 AM, Nealius said:

Only the Su-27 and -33 have FBW systems (29 as well?).

 

soo  there were FBW prior to F18 module yes or not? ... you should fly more simulators and more years before making  assumptions.  

[grafspee]

I remember guy who flew P-51 rated DCS and other simulations for realism and i remember that he said that trim in P-51 works as should in DCS. Question, why suddenly K-4 would have messed up trimming system ? Why make one module near perfect and other light years from realism as many say it is ?

[Nealius]

@IIIJG52_Otto_ This discussion will go nowhere until you recognize and eliminate your own confirmation bias and errors in logic. Not to mention arrogance. The existence of three modules with FBW does not invalidate my statement. Furthermore, LOMAC was before the PFM/EFM fidelity we have today, so the answer to your loaded question of:

4 hours ago, IIIJG52_Otto_ said:

oo  there were FBW prior to F18 module yes or not?

is no, because there were no PFM/EFM modules with FBW modeling prior to the Hornet. 

 

Edited August 25, 2023 by Nealius

[Nedum]

On 8/24/2023 at 11:55 PM, grafspee said:

I remember guy who flew P-51 rated DCS and other simulations for realism and i remember that he said that trim in P-51 works as should in DCS. Question, why suddenly K-4 would have messed up trimming system ? Why make one module near perfect and other light years from realism as many say it is ?

 

I find your question is a bit weird.

Because a RL P51 Pilot has flown a DCS P51 and the RL Pilot said the DCS P51 behavior was ok, the other, total different DCS plane (BF109/K), which this P51 RL Pilot never flew in RL, will tell us, the "not by him flown plane" behaves like it should, even so, the RL flight data was totally different from a restored plane, which was flown also by a RL Pilot, and this flight was showing, the behavior of the restored plane was different to the DCS one? Do I understand that right?
You want to tell us the pure assumption how a BF109/K has to be trimmed, is better than RL flight Data?
So against logic (why in the name of god should any engineer build a plane you can never trim out?) and RL flight data, it must be the thing that's the farthest away of any logic?
Why?
Why do we have horizontal trim plates and can't use them?
Nothing you or the E.D. can tell clears the question, why was the most !not! logical assumption used of how they build the trim system of the BF109/K?
I really don't get it.
If ED has not enough Data to say it's right or wrong, it should for sure the most logical assumption, not that one which is light years away from !any! logic.

But ED did it by 100 % in a way no engineer would ever build a trim system. That's so disappointing.

 

[grafspee]

@Nedum My question was why ED made P-51 near perfect and K-4 totally opposite? What was the logic there?

[Ala13_ManOWar]

On 8/8/2023 at 2:33 PM, motoadve said:

I doubt any Aircraft manufacturer will make a trim like this, has to be a bug, I was thinking just about it yesterday while flying the 109 inside the clouds for quite some time, it would have been very unsafe to fly in IMC conditions fighting the pitch all the time.

That's why those aircraft, any of them, weren't suited for IFR at all. Earlier versions of the 109 didn't even have an artificial horizon nor anything alike. O the drifting horizon in the P-51 and Spitfire, no, those weren't suited for IMC at all.

 

The trim thing in the 109 has been discussed to exhaustion, but the documents used, charts, and all are there, there's even a fixed post somewhere for the suspicious people out there, but charts and documents say what they say. The problem is with moving horizontal surface trim, not the trim itself, it can't be pushed forward because at high speed with that configuration it won't recover a dive, so the recommendation from the test pilot (well known document, with translated to English versions) was to limit trim to 1.15º to prevent unrecoverable dives. Those are the facts, then there're the people's liking and all because in other games it's not like that, but that's a completely different kettle of fish.