109 elevator effectiveness

[E69_geramos109]

This is because the variable incidence tailplane has been implemented, as demanded by die hard 109 fans I might add, as an absolute position mapping for an axis. So they can set and forget instantly. The game then has to more slowly catch up with the input to correctly account for the real speed of actuation of the tailplane trim wheel. When what is designed for an axis is then mapped to two keys instead, the input absolute position is the sum of all the key press events up until the actuation catches up with the input. The trim isn't so broken - it is the best the devs could do to make the stabiliser actuation speed more realistic while trying to support both axis and keybinding for human interface devices lacking any form of force feedback.

Why not to make the operation the same way as on russian fighters. I have not that delay. I understand that the speed of the weel should be limited but i can not understand why i stop ushing the botton and the weel is still turning like 1 or 2 positions more. This is just broken. There are more ways to do it as it is on the flaps. You pres the button the flaps moove, yo stop presing it and the flaps stop... Is just as simple as that.

[1PL-Husar-1Esk]

Well if we speak about game and 109 structural strength, I did and witness rip-off wing by rapid use of stabilizer to pull out from dive (before FM patch).

[LLv34_Wmaker]

As it is widely known, the elevator control forces of the Bf 109 were very high for a fighter at roughly 8-9kp per G* (which basically puts it in the light bomber class). Mr.Raunio mentions that at 500km/h a pilot with normal strength could generate a pull with acceleration of 4Gs (a force of 32-36kp).

 

I tested using Tacview how many Gs can be generated at a low altitude turn at 500km/h in the sim. In very a simple test I just dove down to the deck flying Bf 109G-2 with a speed well past 500km/h (ground speed), banked the aircraft into a steep turn (roughly 80 degree bank) and pulled the stick all the way back. As the aircraft started the decelerate, 4Gs were achieved at 549km/h, 5Gs at 524km/h where it remained until 485km/h and peak acceleration of 5,3Gs was achieved and kept through the speed range of 443-419km/h.

 

It is indeed thought that Willy Messerschmitt wanted to protect the aircraft structure and that was the reason for the high control forces as the ways how to reduce them were indeed well known. Mr.Raunio writes that the problems with the early F-models' tails breaking off in dives might have contributed to this and also fittingly mentions that far less heavy control force would have sufficed.

 

(*Jukka Raunio in his excellent book Lentäjän Näkökulma II)

Edited November 3, 2017 by LLv34_Wmaker

[CisTer-dB-]

Just for curiosity, looking through the document posted above, I decided to take the 109 F for a short spin. Two things beacame apparent.

 

1) The elevator authority is not far off what is stated on the document.

2) The 109 lives no where near up his actual structural strenght. Just look at that.

 

 

 

 

 

What is most apparent, is that the way the "engine timers" are implemented, it negates an often applied strategy to disengage. Prop overspeed is punished right away, even though full speed power dives were the rule to disengage, not the exception. Even at speeds that are well below actually reached speeds, we lose contol surfaces. Also the engine gets killed by the overrev. They absolutely should not quit like this. But it seems that the hard wired engine timers play us a trick here.

 

What is also nonsense, is that the engine (in the 109 F4 tested), way above critical altitude still has a power timer. This means 100% throttle gets punished even though I am nowhere near a power output that could be harmful to the engine. At 10'000 meters, you can open up as much as you want, you NEVER reach "Combat Power" or whatever power. But there, the evil RPM probably play us the trick, even though the engine runs at half the power.

 

We definitely need to buy more stuff from the dev team giving them the opprtunity to re think some strategies.

 

 

So I agree that there are issues with the 109 and its elevator. But not as long as they stay attached.

Hi Zak as per the test report that you did for the test that I presume that screen shot was taken. Here a copy and paste from the original post. That might have been the reason why you have lost your ailerons 

 

 (enlarged vertical stabilizer without radio wire horn, and for the sake of the test also enlarged static trim tabs and reduced aileron travel to prevent airplane loss due to aileron reversal).

Edited November 3, 2017 by ATAG_dB

[CisTer-dB-]

Hi, this is very interesting report.

 

All the tests were made with nose-heavy trim to be able to reach high dive angle. For example on page 8 it says that the neutral trim (+1.0 deg) had to be changed 0.5 deg to nose-heavy in order to be able to keep down the nose to the 45 deg dive angle at 730 km/h indicated speed.

 

They did two tests (page 9 and the diagram on page 10) at 1.25 and 1.75 degrees nose-heavy. The test was dive from 10.5 km altitude at 75-80 deg. angle reaching 745 km/h indicated and 880 km/h true speed at 3.8 km, after which the pilot pulled out.

 

The report states its possible to pull out of the dive using only the elevator at 1.25 degrees setting. Then at the 1.75 deg. nose-heavy setting the pilot had to use the trim as well.

 

 

Now, in the game we have completely different story. In the game diving in neutral trim gets you splashed into the ground. Not to speak of nose-heavy... In the game you have to trim tail-heavy in advance and push hard to keep the nose down on target which of course ruins your aim...

 

I might be lost in translation but he is saying the opposite, from what Inkompetent wrote at the least. I don't speak German unfortunately  

 

 

If looking at actual test reports for 109s (for example Versuchs-Bericht Nr. 109 05 E 43 - Hochgeschwindigkeitsversuche mit Me 109 (dated April 15, 1943)) they do take note of significant required stick forces at high speeds (meaning about 750 km/h indicated at ca. 3.5 km), and that it not only was recommended but pretty much necessary to trim out of a high-speed dive, because the pilot couldn't safely do it in a controllable manner with just muscle power. That was done in a Bf 109 F-2 (I looked up the Werknummer), modified to match a G-series (enlarged vertical stabilizer without radio wire horn, and for the sake of the test also enlarged static trim tabs and reduced aileron travel to prevent airplane loss due to aileron reversal).

Basically the report supports the already pre-existing recommendation in the flight manuals to trim the 109 tail-heavy in a high-speed dive, so that you need to push the stick forward to stay on the dive path, because otherwise maintaining an even dive path and in particular pulling out of the dive will be a bitch.

 

 

Might be that the elevator is a tad too stiff, but we also have a propensity to dive at Mach 0.8 (basically at the plane's V_ne-speed) in straight-winged planes with wire-and-rod controls and fabric-covered control surfaces and then complain about control stiffness. If diving at actually sensible speeds - like 650 km/h at 3.5 km - stiffness isn't really much of a problem unless the enemy spots you and actively evades, but I'd like to see anyone who can show me that wasn't the case IRL too.

Edited November 3, 2017 by ATAG_dB

[L3Pl4K]

I might be lost in translation but he is saying the opposite, from what Inkompetent wrote at the least. I don't speak German unfortunately

Most interesting pages are 9-10. In this flights the 109 had the:

-Gustav tailfin

- enlarged static trim tab

-reduced aileron travel

The trim was setup to +1° 15` for the dive.

Dive was initiated with a downturn(Abschwung).

After the downturn stick must be pulled(nose heavey at lower speed).

With increased speed and dive angle, stick must be pushed.

From 850km/h Vw (real speed) stick force go to zero.

With pulling the stick, it was possible to end the dive.

 

Without a downturn, the machine needs too much time, to speed up. The force to push the stick are to great and it is not possible to maintain the dive angle. If the trim is setup 0,5° more nose heavy, forces to push the stick are reduced. With increased speed, stick force invert.  In this case trim wheel is needed to end the dive.

 

To understand the diagramms:

ziehen=pull

druecken=push

Edited November 3, 2017 by L3Pl4K

[Willy__]

This did happen some days ago.

Pe-2 downed, and soon after my tail section has been ripped off by a burst of three 12,7. Pe-2 was grounded.

 

http://il2stat.aviaskins.com:8008/en/sortie/log/2474897/?tour=28

 

Nobody here says it was not, but just only that probably the 109 structure, in the tail section, is a bit too fragile or again, that the AP are overmodelled a bit.

 

..i don't have the track.

 

Also known as "the toothpick effect" or "the toothpick 109" 

[Holtzauge]

 

Reading throug Holtzauge's post, I wonder why they didn't change the control gearing such that you could move the stick easier. One thing for sure, there are structural issues. You have to be very, very careful moving your controls at high speeds. Older "analog" airliners like the DC-9 (mostly just Flettner control) or the DC-10 with added inboard (just inside the engine nacelles) hydraulic ailerons show how you can realize such. Didn't the P-38 have geared tabs in the elevator? Yes why not doing such on the 109? It is no secret that, even though the 109 was extensively redesigned over the different types, it did not have the structural rigidity of the Fw-190. This sets limits. So i'm not so sure if you can take an airframe and just give it good high speed stick authority without asking for troubles.

 

One thing to keep in mid is, properly trimmed, you can speed up and shoot someone in the back and then run with the 109. But what you cannot do is take a fight at 400 mph with a Tempest or a Mustang. And I doubt that any of the aces really did that with the 109. Once it came to maneuvering, planes were probably much slower soon.

 

The 109 was maybe a fast plane, but it had a comparably low combat speed by late war standards. So if one gets used to that, why change it? People got used to it, and the ones that lived to talk back to Willy were even rather sucessful with it. So why change it all?

 

Changing the stick gearing so that the forces go down requires more throw on the stick or that you keep stick travel (throw) constant and instead limit the maximum control surface deflection.  I’m pretty sure they would have done either if they had a chance but they most likely needed both the elevator deflection range they had and I’m pretty sure there was no more room for stick travel either.

 

As it is widely known, the elevator control forces of the Bf 109 were very high for a fighter at roughly 8-9kp per G* (which basically puts it in the light bomber class). Mr.Raunio mentions that at 500km/h a pilot with normal strength could generate a pull with acceleration of 4Gs (a force of 32-36kp).

 

I tested using Tacview how many Gs can be generated at a low altitude turn at 500km/h in the sim. In very a simple test I just dove down to the deck flying Bf 109G-2 with a speed well past 500km/h (ground speed), banked the aircraft into a steep turn (roughly 80 degree bank) and pulled the stick all the way back. As the aircraft started the decelerate, 4Gs were achieved at 549km/h, 5Gs at 524km/h where it remained until 485km/h and peak acceleration of 5,3Gs was achieved and kept through the speed range of 443-419km/h.

 

It is indeed thought that Willy Messerschmitt wanted to protect the aircraft structure and that was the reason for the high control forces as the ways how to reduce them were indeed well known. Mr.Raunio writes that the problems with the early F-models' tails breaking off in dives might have contributed to this and also fittingly mentions that far less heavy control force would have sufficed.

 

(*Jukka Raunio in his excellent book Lentäjän Näkökulma II)

Very interesting info about the IRL stick force per g and a speed to go with that as well. Finally something tangible! Do you have any details how they measured that and any assessment on accuracy?

 

Also, thanks for doing the Tacview testing! Based on your testing then it looks like the modeling we have today in-game of the Me-109’s elevator stick force is pretty accurate at 400-500 Km/h then. If anything it even looks like it is a bit on the optimistic side.

 

Regarding that the heavy elevator was intentional as a protective measure against overloads, I think that would apply to overloading the wing since I’m pretty sure that would be the first thing that fails if you have sufficient pitch authority at high dynamic pressures. The reason I don’t think the tail would fail due to elevator input is that you would not need to load the tail assembly that much in order to change the aoa of the main wing to a level where the main wing would fail due to g-overload.

 

AFAIK the reason late war fighters lost tails due to structural failures was different: Usually the late war fighters were equipped with larger and larger propellers (either more blades or blade area to absorb the increased power) but in many cases retained the same tail volume (as in tail area x lever length) which led to a reduced stability in yaw and pilots had to be very careful and were warned about excessive yaw angles. IIRC then the Mustang, Tempest and Spitfire all had failures where the rear fuselage broke off that were attributed to a too high yaw angle in high speed dives, not that they broke off due to elevator input. On the Spitfire there were of course structural failures due to the low elevator stick forces as well but AFAIK what failed (first I mean) in those cases was the main wing. I don't have all the details here but I believe Kurfurst is a good source for Spitfire structural failures, both in terms of numbers and reasons since he can be relied upon to keep good tabs on that kind of data.

Edited November 3, 2017 by Holtzauge

[ZachariasX]

Hi Zak as per the test report that you did for the test that I presume that screen shot was taken. Here a copy and paste from the original post. That might have been the reason why you have lost your ailerons (enlarged vertical stabilizer without radio wire horn, and for the sake of the test also enlarged static trim tabs and reduced aileron travel to prevent airplane loss due to aileron reversal).

 

Actually I didn't make any movements with the controls other than pushing the plane into the dive in the case where I started out with a neutral trim, in our case -50%. I also did dives with trim full forward.

 

I deliberately didn't move the controls otherwise, as I was curious how the longitudinal instability was modelled, and I found that surprisingly well done. For the record, I did the with the 109 F4 in our game.

 

When not deflecting controls, control surfaces should not detach. They dived at higher Mach numbers than I did in these short trials.

 

Under normal conditions, you have to be a bit tail heavy when entering a power dive. As you get faster nose will come up and you have to fight that up to the point of critical Mach, when the nose progessively wants to lower. So you will reach the point where the Mach tuck will cancel the nose-up tendency of the high speed. Going faster, the Mach tuck will incrasingly rapid push your nose down to an extent that makes it absolutely impossible for you to counter it with the controls. If you don't have the credit of a significant up trim, you're in deep trouble.

 

Should you trim for fast flight, then the Mach tuck will make it impossible for you to raise the nose unless you use the trim.

 

The problem with using trim to exit the power dive is that as soon as you pull up the nose with the trim, this little input will result in high  G load, most likely blacking out the pilot. As the plane decellerates very rapidly in such a pull up, the Mach tuck will fade quickly as well as it is counterd by the lower and denser athmosphere, further increasing G loads on what you though was a reasonable pullout when you set your trim. Thus, when you use trim for pull out, initailly the aircraft will do so to your liking, but suddenly it will pull up as if it was gone mad, preventing you doing any control input at all. In this state, you may well break up your aircraft. And this is why exiting power dives near critical Mach is inherently dangerous.

Edited November 3, 2017 by ZachariasX

[Holtzauge]

Most interesting pages are 9-10. In this flights the 109 had the:

-Gustav tailfin

- enlarged static trim tab

-reduced aileron travel

The trim was setup to +1° 15` for the dive.

Dive was initiated with a downturn(Abschwung).

After the downturn stick must be pulled(nose heavey at lower speed).

With increased speed and dive angle, stick must be pushed.

From 850km/h Vw (real speed) stick force go to zero.

With pulling the stick, it was possible to end the dive.

 

Without a downturn, the machine needs too much time, to speed up. The force to push the stick are to great and it is not possible to maintain the dive angle. If the trim is setup 0,5° more nose heavy, forces to push the stick are reduced. With increased speed, stick force invert.  In this case trim wheel is needed to end the dive.

 

To understand the diagramms:

ziehen=pull

druecken=push

 

Maybe it would be good to add that the conclusion was that it was not recommended to trim into the dive because if you did, recovery with the elevator was impossible and you had to use the stabilizer to recover and in those cases it was easy to overload since the aircraft tended to tighten up and increase the g-load as the speed was reduced.

 

Edit: Zacharias post above explains what is going on in more detail and is good background info to why the Me-109 behaved like it did in the test I think.

Edited November 3, 2017 by Holtzauge

[ZachariasX]

IRC then the Mustang, Tempest and Spitfire all had failures where the rear fuselage broke off that were attributed to a too high yaw angle in high speed dives, not that they broke off due to elevator input.

Yes, they had to enlarge the fins. Especially in the case of the Mustang, rudder was so light, that you could yaw the aircraft at high speeds to angles that would compromise its structural integrity.

 

Not having a tail fin large enough for safe flight was a common disease. Even the Bearcat had a tiny tailfil in is first prototype. They just made one short flight with that model. The Tempest also only had a larger fin an a later try. In the beginning it had the tail of the Typhoon.

 

That the Spitfire would break up in flight is rather news to me. There are some quotes of Jeffrey Quill about meding some issues on the Mk.V. ragarding stability. But other than that the Spitfire was known to be a very solid aircraft and the crews trusting it and always taking it to the limit without fear of break up was a big plus.

[VesseL]

Why not to make the operation the same way as on russian fighters. I have not that delay. I understand that the speed of the weel should be limited but i can not understand why i stop ushing the botton and the weel is still turning like 1 or 2 positions more. This is just broken. There are more ways to do it as it is on the flaps. You pres the button the flaps moove, yo stop presing it and the flaps stop... Is just as simple as that.

 

My stabilizer is mapped to thump wheel on my throttle. The mechanics is the same thou. I roll the wheel some, and the counter start to run the %´s. I used to use the whole range from 100% to -100%. Now i use mostly only the range from 0% to -100%. It is just too slow to use the whole range anymore.

 

Is the real life russian trim wheel faster to roll from one end to other?

[VesseL]

Well if we speak about game and 109 structural strength, I did and witness rip-off wing by rapid use of stabilizer to pull out from dive (before FM patch).

Cant do that now. So before or now, which one is the right interpretation?

Edited November 3, 2017 by VesseL

[curiousGamblerr]

Why not to make the operation the same way as on russian fighters. I have not that delay. I understand that the speed of the weel should be limited but i can not understand why i stop ushing the botton and the weel is still turning like 1 or 2 positions more. This is just broken. There are more ways to do it as it is on the flaps. You pres the button the flaps moove, yo stop presing it and the flaps stop... Is just as simple as that.

 

Because that makes no sense for an axis. Think about it- with an axis you can't both limit the speed and immediately stop when the real life axis stops moving. 

[Holtzauge]

Yes, they had to enlarge the fins. Especially in the case of the Mustang, rudder was so light, that you could yaw the aircraft at high speeds to angles that would compromise its structural integrity.

 

Not having a tail fin large enough for safe flight was a common disease. Even the Bearcat had a tiny tailfil in is first prototype. They just made one short flight with that model. The Tempest also only had a larger fin an a later try. In the beginning it had the tail of the Typhoon.

 

That the Spitfire would break up in flight is rather news to me. There are some quotes of Jeffrey Quill about meding some issues on the Mk.V. ragarding stability. But other than that the Spitfire was known to be a very solid aircraft and the crews trusting it and always taking it to the limit without fear of break up was a big plus.

 

I found the thread with the info I was referring to earlier: It was at WW2aircraft.net and and was titled "weaker wing, 109 or Spitfire?"

 

It is 6 pages long and ends in tears but in addition to a lot of useful info has a certain dark entertainment value as well.

 

Anyway, there is some good info on Spitfire mid air structural failures from the excellent Spitfire book by Morgan & Shacklady and I post a few images below but you can find lots more in the thread I linked.

[ZachariasX]

I found the thread with the info I was referring to earlier: It was at WW2aircraft.net and and was titled "weaker wing, 109 or Spitfire?"

 

It is 6 pages long and ends in tears but in addition to a lot of useful info has a certain dark entertainment value as well.

 

Anyway, there is some good info on Spitfire mid air structural failures from the excellent Spitfire book by Morgan & Shacklady and I post a few images below but you can find lots more in the thread I linked.

Ah, thnx for these! From a first look, it seems that the planes wouldn't just fail like that. But when consistently abusted by rough ground treatment and frequent episodes past Vne, the poor crates seem to age fast.

 

In case of the Spitfire, the wing was a constant concern. They tried to solve it by clipping the wings for the first time in the Mk.VD, where that intention was supplemented with the intention to increase roll rate. That it was more just increasing roll rate is illustrated in the repetition of the hated clipping of the wings in the Mk.XIV. This type, being considerably faster, has shown a lot of skin wrinkling. It was only supposedly to be fully cured in the Spiteful Mk. XIV, the "Spitfire" that no one needed anymore.

 

The Bf-109K, being kept half a ton lighter than the Spit XIV (with a similar sized engine), surely carried little reserves in durability.

 

I guess designers on both sides had to make compromises not just regarding in-flight breakups, but also for durabilty in field use. Maybe Williy had is way like this to produce an extremely light fighter with such a big engine.

 

In the Bearcat, structural overload had another funny limiter: the outer wing parts would simply break off if the pilot pulled >7.5 G. It is of note that in the Bearcat, this is a rather easy thing to do. Eric Brown mentined that no airplane gave him more blackouts than this, with the A6M Zero coming in the same league.

[ZachariasX]

It was at WW2aircraft.net and and was titled "weaker wing, 109 or Spitfire?"

What a thread

 

One thing that really doesn't seem to be obvious to some, is that with "normal" aircraft, as well as with these WW2 birds, you can't just pull more g's the faster you go until corner speed, where you are capped at the structural limit of the aircraft.

 

In these planes, you can pull more g's until you reach maximum maneuver speed that the plane is designed for. Now, for these fighter aircraft, this should well be around corner speed. However, as you progressively go faster, the structural g limit of your airframe gets capped and the max. g you are suppsed to pull is drastically reduced, about by half. If your average fighter is good for 8 g's without the mechanic cursing you and your kin, then at alevated speeds (something like 2/3rd of Vne), you get your max. perimissible g about halved.

 

In short, you can pull until blacking out during combat speed, but in diving speeds, you have only half of that credit. The rigging of your stick forces should reflect that. They should give you the deflection you need at maneuvering speed, but they should seize up enough to fly "nice" at high speeds. This also as a protection for accidental overstressing of the airframe.

[VesseL]

I made some tests. 109g2 Stabilizer rolls 6 full turns. Yak and la5 trimwheel turns 2,5 turns. 109 it takes 16sek full turn one end to other, and yak and la5 it took 8sek. Dont know how long it took irl. But the relative time seems about right.

 

Then i did fly the quick mission. 5000m alt, full throttle all the way from start to finish, and boost on, if the ac have one.Also i did trim them all elevator -100%( full nose down and kept it there during the whole test).At 5000m i rolled right and dived staight down at90 decree to ground and when IAS was 750kmh i did pull the stick full back and kept it there. i test 109g2, spit, yak and p40, and only one that survived without breaking was the p40. It was easy for p40. Only one that grashed to ground was 109. Yak did lost all controls, aileron,elevator and rudder, but somehow it still continued turn the same radius, than before contols ripped off. Spit lost the ailerons and rudder but one elevator was stil working after the dive and it survived. It didnt matter if i used the full throttle or idle throttle( at 750kmh i did lower the thottle at 0%, same time as i did pull the stick full back), the results was the same. I dont know what this all means but 109 was the worst of them to recover from dive in that test.

[ZachariasX]

5000 m is very, very low for such a test. Trimming 100% into the dive spells intent of sucide.

 

It seems the devs did things mostly right. You see, in the 109, you trim the stabylo. This means you’re still pushing in the dive once your control surfaces detached. In the other plane, you lose the trim tab along with the rudder.

 

You yanking stick full back at and past Vne is „not good“. The devs programming things such that you are shedding controls then means that they are doing things right and that they assume you to be a strong pilot.

 

Control surfaces should not detach when not deflected, unless they would experience flutter. I do not know how the devs implemented these stresses, but at first glance, you obviously wanted to die and devs are not far of the mark.

[VesseL]

Atleast spit did push nose down muuuch more than 109. Dont know why. I miss some nose down attitude from 109g2. it has it more before,

[VesseL]

5000 m is very, very low for such a test. Trimming 100% into the dive spells intent of sucide.

 

It seems the devs did things mostly right. You see, in the 109, you trim the stabylo. This means you’re still pushing in the dive once your control surfaces detached. In the other plane, you lose the trim tab along with the rudder.

 

You yanking stick full back at and past Vne is „not good“. The devs programming things such that you are shedding controls then means that they are doing things right and that they assume you to be a strong pilot.

 

Control surfaces should not detach when not deflected, unless they would experience flutter. I do not know how the devs implemented these stresses, but at first glance, you obviously wanted to die and devs are not far of the mark.

 

109 was the only plane that killed the pilot in this test(maybe useless test if i made some mistake). But i tried to be objective, and the situation was the same to every ac in that test. So are you saing that because stabilizer is so different than elevator trim, the 109 couldnt pull up and survive. But yak because it lost  the elevator, and all its controls, naturally was able to pull up from the dive

[ZachariasX]

Atleast spit did push nose down muuuch more than 109. Dont know why. I miss some nose down attitude from 109g2. it has it more before,

The Spit has very light elevator control. It is supposed to be like this.

 

The 109 trim seems to me to have on average a bit of a nose up tendency over the speed range. It is much in line with Ottos complaint. But I wouldn‘t know how much in absolute terms it would be. What is for certain howver, in that the behavoiur of the 109 in principle is much improved. So for shooting up stuff, it is a big step forward in realism I think.

109 was the only plane that killed the pilot in this test(maybe useless test if i made some mistake). But i tried to be objective, and the situation was the same to every ac in that test. So are you saing that because stabilizer is so different than elevator trim, the 109 couldnt pull up and survive. But yak because it lost  the elevator, and all its controls, naturally was able to pull up from the dive

The point is that the Yak will revert to a neutral trim (that is lots of nose up at Vne) once control surface along with the trim tabs are gone. As soon as the are off, you are at 0% trim. On the 109 you still have nose down trim because the stabylo is still on an gives you -100% trim. Kaboom.

[1PL-Husar-1Esk]

smalltalk continues...

[VesseL]

Ok thanks, yak will fly level if all controls are ripped off? Then it could explane that recovery. But i have to make other test where i make sure the controls will rip off when Yak´s nose is still pointing down. That sure yak cant recover?

smalltalk continues...

 

 this is elevated smalltalk.

[von_Tom]

Well the 109 did some pretty amazing manoeuvres in Red Tails.

 

 

 

...

 

 

...

 

 

 

Sorry I just wet myself laughing.  I've just managed to sit through 28 minutes of it before I couldn't face any more,  I feel somewhat soiled.

 

von Tom

[III/JG52_Otto_-I-]

The point is that the Yak will revert to a neutral trim (that is lots of nose up at Vne) once control surface along with the trim tabs are gone. As soon as the are off, you are at 0% trim. On the 109 you still have nose down trim because the stabylo is still on an gives you -100% trim. Kaboom.

Don´t forget that today AIRBUS airplanes, have the THS (Trimmable Horizontal Stabilizer) same as Bf-109, with mechanical controls cables for providing a back-up control in pitch axis. It is a fail-safe system which Dr. Eng. Willy Messerschmitt, used from early the Bf-109 for the same reason. 

Edited November 5, 2017 by III/JG52_Otto_-I-

[ZachariasX]

Don´t forget that today AIRBUS airplanes, have the THS (Trimmable Horizontal Stabilizer) same as Bf-109, with mechanical controls cables for providing a back-up control in pitch axis. It is a fail-safe system which Dr. Eng. Willy Messerschmitt, used from early the Bf-109 for the same reason. 

They also make their Busses neutral in pitch axis control, same as Reginald designed his Spitfire. And this then and now, is a problem if you are not really a proficient pilot.

[Dave]

Why not to make the operation the same way as on russian fighters. I have not that delay. I understand that the speed of the weel should be limited but i can not understand why i stop ushing the botton and the weel is still turning like 1 or 2 positions more. This is just broken. There are more ways to do it as it is on the flaps. You pres the button the flaps moove, yo stop presing it and the flaps stop... Is just as simple as that.

 

You'd have to ask the devs for a specific answer regarding their reasoning for implementation choices. But for one thing, the mechanics of pitch trim in the 109 are very different from those of all Russian aircraft. Russian aircraft use trim tabs on the primary control surfaces. Trim tabs have very low forces opposing their operation. It is the reason for their design. The 109 does not use trim tabs, instead featuring a variable incidence tailplane. The latter is meant to be more efficient, producing less form drag because the elevators are not deflected as far into the airstream (I admit I have never calculated the relative efficiencies and forces involved - its on my todo list).

 

Regarding your specific problem of "i can not understand why i stop *pushing the *button and the *wheel is still turning like 1 or 2 positions more" this would be a consequence of mapping discrete input events (button repeat) to a continuous input (axis). The same thing happens on Russian aircraft but is less noticeable due to the speed of actuation.  Whilst ever you keep holding a key or button to which you have mapped stabiliser adjustment the target value for the adjustment keeps increasing (or decreasing). Simultaneously the actual position of the stab is catching up to this target with some amount of delay to account for the mechanical limitations of the control. At the time you cease pushing the button the wheel still hasn't caught up to the target value accumulated for the pitch trim change, so the wheel keeps turning. I understand your issue and I think it would probably be better to implement this particular control, when using discrete input such as buttons, as "when I stop holding the button stop turning the wheel", but that would create a problem for people who map this input to an axis. An axis is an absolute input device. If I understand correctly, and here I am making educated guesses of the implementation base upon observed behaviour, the 109 pitch trim input first converts discrete inputs to absolute values so they can be processed by the same code path that handles axis inputs. This would explain the delay you observe.

[Dave]

Don´t forget that today AIRBUS airplanes, have the THS (Trimmable Horizontal Stabilizer) same as Bf-109, with mechanical controls cables for providing a back-up control in pitch axis. It is a fail-safe system which Dr. Eng. Willy Messerschmitt, used from early the Bf-109 for the same reason. 

An A340 would have a similar problem if you attempted to dive it from altitude, disable the hydraulic tailplane actuators (so you are relying on the mechanical backup system) and attempt to pull out near Vne near the ground. Modern airliners use the THS for efficiency in cruise with varying weight-and-balance conditions due to varying take-off load distributions and fuel burn in flight. Their motivations have almost nothing in common with those of Messerschmitt in his design for the 109. Honestly some people's projections of Willy Messerschmitt's design prescience border on pure fantasy.

[Dave]

Then i did fly the quick mission... i did trim them all elevator -100%( full nose down and kept it there during the whole test) ... when IAS was 750kmh i did pull the stick full back and kept it there. i test ... p40, and only one that survived without breaking was the p40. It was easy for p40.

 

Hmmm. Really? This doesn't gel with my experience of the P40 in game - and I fly it almost all the time. On the P40 you would need quite a bit of nose down trim to keep the nose from lifting at 466mph (Vne for the P40 is 475mph IIRC). But then pulling out of a vertical dive at this speed with full nose down trim should be impossible. I've never been able to do it without trimming out. For this reason I never trim into a dive in the P40. You want it to self recover. Granted my experiences of these pull outs has not been at such a high altitude that I can just wait for it to slowly recover.

Edited November 6, 2017 by Dave

[VesseL]

 

The 109 trim seems to me to have on average a bit of a nose up tendency over the speed range. It is much in line with Ottos complaint. But I wouldn‘t know how much in absolute terms it would be. What is for certain howver, in that the behavoiur of the 109 in principle is much improved. So for shooting up stuff, it is a big step forward in realism I think.

 

The point is that the Yak will revert to a neutral trim (that is lots of nose up at Vne) once control surface along with the trim tabs are gone. As soon as the are off, you are at 0% trim. On the 109 you still have nose down trim because the stabylo is still on an gives you -100% trim. Kaboom.

 109 had been nerfed since 2015. It was way better fighter in game than it is now, that is a fact. It feels more realistic now but its not much of a fighter anymore. Yes its still good if flown with squad but alone its mediocre. Its only good for avoiding fight. G2 has been my main ac, but now its so boring. P40 is like another level, and so is la5. Much better now. Current 109g2 has made me a below average pilot. I wever was a top ace and never will be, but i was ok.

 Thanks all, seems like 109g2 is spot or right now. Thats good.

 

Hmmm. Really? This doesn't gel with my experience of the P40 in game - and I fly it almost all the time. On the P40 you would need quite a bit of nose down trim to keep the nose from lifting at 466mph (Vne for the P40 is 475mph IIRC). But then pulling out of a vertical dive at this speed with full nose down trim should be impossible. I've never been able to do it without trimming out. For this reason I never trim into a dive in the P40. You want it to self recover. Granted my experiences of these pull outs has not been at such a high altitude that I can just wait for it to slowly recover.

 Yes really.

[Dakpilot]

An A340 would have a similar problem if you attempted to dive it from altitude, disable the hydraulic tailplane actuators (so you are relying on the mechanical backup system) and attempt to pull out near Vne near the ground. Modern airliners use the THS for efficiency in cruise with varying weight-and-balance conditions due to varying take-off load distributions and fuel burn in flight. Their motivations have almost nothing in common with those of Messerschmitt in his design for the 109. Honestly some people's projections of Willy Messerschmitt's design prescience border on pure fantasy.

I have to agree with the last point specifically, it is fortunate that Airbus Industries did not use the Me 210 as inspiration

Willi Messerschmitt was a (flawed) genius and the 109 was a great aircraft, but like all it had compromises and foibles, (some) people need to look at the bigger picture.

 

Ideally we would all have a life size trim wheel with the correct amount of turns mapped to it, but then what for those with a 1 centimetre rotary knob? It can be turned much quicker so there has to be a delay in reaction, same with buttons, you cannot have direct corellation of button press to in aircraft trim wheel movement,it just does not work, there have to be compromises to avoid exploit and still have reasonable accuracy of time taken for complete movement and usable sensitivity

 

Cheers Dakpilot

[LukeFF]

 

 

Yes its still good if flown with squad but alone its mediocre.

 

 

Any plane is mediocre if flown alone.

[VesseL]

 

 

Any plane is mediocre if flown alone.

 

NO! 109 was a good plane before, even flown alone. Not anymore.

 

I loved 109g2, now i hate to fly it.

Edited November 6, 2017 by VesseL

[VesseL]

109g2 turntime over 23 sek? Is that historically accurate? Spit about 16sek? Yes historically accurate sure thing.

 

And some allied pilots here say that the real 109 pilots dont speak the truth. Or they dont know their plane as well as some here do. How arrogant.

 

Btw in the p40 thread there were no fm police whining how you dont know that p40 is just like it was irl. That there is nothing to correct with it. 190 thread there were many of you whining about whining. And what happend then? at the end you were wrong, and then you were like you knew it butbutbut...... Its like some disease here, that kind of whining.

[VesseL]

Think about this, The devs dont know how it was. If they know they wouldnt need to correct anything. And they have all the secret documents and all to use and still they make mistakes( which is totally understandable, and i dont blame them for anything, how could i). They know more than any of us here. So you fm police here, dont be so sure you know how it was, cause you dont, even if you have flown a real aeroplane.

[LukeFF]

Imagine in WW2 the mecanics of the Axis & Allied planes and the dessingners are the Soviets : like here . Savotage EveryWhere .....

 

 

In Dcs every company develope their own plane like VEAO AV8Harrier , Eurofighter ...

The heck are you rambling on about?

[ITAF_Rani]

I was shoked also AFTER LAST UPDATE..BF109 F4 is less manouvrable at high speed..but..

After new trainig last month I can say we have to relearn how to fly the beast.

It s always a great plane..we have to be.more carefull and how to work with trim and trottle is a must now.

Don't know if the actual FM is close to real or no but about this great sim fliyng the 109 is always fun !!

[VesseL]

Rani, Its fun, agree, and F4 is better 109. Still, like p40 pilots knew, that p40 was not ok, i "know" 109g2 is not ok now. It doesnt feel the same as i have heard it was. And it doesnt feel the same as it has always been in a sim. Its much harder to boom and zoom with G2 ,than it is with p40 or yak, or la5, or any other ac exept F4 i think. That is just odd. The boom zoomer is the worst boom zoomer. Now even 500kmh makes controls too stiff to follow any enemy who see you. I would expect that about speeds above 630kmh, not at 500kmh. Also G2 turns too slow now. Just my 2 cents i know.

 

Dont hate me Windmills. That is my opinion, nothing else. I mean no harm for the game.

[Kurfurst]

109g2 turntime over 23 sek? Is that historically accurate? Spit about 16sek? Yes historically accurate sure thing.

 

IIRC the Soviets tested both (G-2 captured at Stalingrad, and a Lend Lease Spit LF IXc) and measured 20 secs and 18 secs respectively for a 360 degree sustained turn at 1000 m altitude.