Something interesting about Fw190s...

[hazed-]

Recently i watched a tv program on discovery wings and it was describing various types of aircraft and what each type is favoured for.Things like a fighter needs a weight to thrust ratio of at least 1:1 to be effective.The F16 i think it was had a 1.1:1 thrust ratio so from the runway it can point straight up and climb away. great to see.

Then it went on to stunt aircraft and the pilots describe how they favour stable and accurate controls and aircraft that have an immediate response and tend not to yaw.
They then described how stunt planes dont use wires but rather control rods to control the ailerons and this means they have a much more positive response.As the interveiw went on and they described various things about the way stunt planes were made it struck me that they described lots of things the 190 had.

The way the pilot sits and the position. The shorter wings but most importantly the 190 has those same control rod actuated ailerons!
The thought suddenly struck me that in AH the 190s are a fairly good platform for firing but they have a real tendancy for the nose to bounce around quite a bit. It certainly doesnt feel any more stable than other aircraft. I just got to wondering if maybe the control rod controls on the 190's we have have been reproduced properly.After all if to this day stunt pilots use the same device for ailerons so they can perform accurate maneuvers how come our 190s are so mushy in the air? Im not saying its wrong because obviously i havent been in a real 190 but are their rod controls factored in to the AH model?

I suppose the weight of guns etc would play a large role and this is most likely why they mounted them so close to the centre of rotation, and probably why most 190 pilots favoured no outer cannons mounted.but those controls must have been better than wires else they wouldnt be using them today in very expensive stunt planes would they? If you agree im not sure but to me the 190 doesnt feel like it has an especially sharp/accurate control.For me the nose tends top yaw and pitch quite a bit.

anyhow heres a quote from FW190in combat by Alfred price ISBN 0-7509-2548-5 about these controls taken from an interveiw with Kurt tank concerning the design for 190s:

page 4
"Although the new fighter had to be rugged it had to handle well in the air.The secret of this was to make the control surfaces large enough and to balance them with great care, both statistically and dynamically; if they were underbalanced they became too heavy and lost effectiveness, if they were overballanced this caused other problems. The design team did a lot of work to get a positive and immediate response from the flying controls.They decided to use rigid rods between the control column and the flying control surfaces instead of the more usual wires and pulleys. In service the latter were liable to stretch, and the resultant play made the controls less 'crisp'."
further page 5
"Once the controls were correctly balanced, it was important to ensure that they stayed that way over a wide range of speeds.A fighter pilot did not want to have to re-trim the aircraft each time he moved the throttle.The team were so successful in this that they found that movable trim tabs were unecessary.Small fixed trimming tabs were fitted to the ailerons, the elevators and the rudder."

all seems to suggest a very stable platform.Would you agree this isnt quite what you feel in the AH 190? or do you think that the guns etc would make it behave just as it does now in AH?
If you think its ok I'd like to ask why you think they used rods instead of wires if there wasnt a marked difference? seems strange to me.If the bounce is caused by the unballancing guns weight shouldnt this effect be markedly worse for any aircraft that has its guns mounted in the middle or outer wings?

Think about it, the 190 has the guns mounted much closer than most aircraft. They mounted them there for a good reason i think . Because in order to maintain stability and ballance they took a hit on the guns RPM by firing them with interuptor gear,through  the props.
I feel the 190's in AH bounce much like all other aircraft and not only that they actually seem to take a longer time to trim into level flight etc on auto trim.A plane that supposedly needed little if any trimming in RL.

[hazed-]

ok some more interesting stuff

FW190 in combat by peter caygil:

"Although the need for fighter aircraft to defend the homeland was great, the Fw190 was exported in small numbers commencing the sale of 72 Fw190a-3's to Turkey in 1943.These aircraft were supplied in the early lufftwaffe desert camoflage scheme of mottled brown/green.The armament was restricted to two MG17 machine-guns mounted over the engine and two MG-FF cannon in the outer wings.The wing root guns were deleted.
  The Fw190s were used by the 3rd and 5th squadrons of the 5th regiment,Turkish Airforce and were often flown alongside SpitfireV's that had been supplied in 1944.Both types remained in service until at least 1948"

hows that for a weird pair to come face to face with in a dogfight?

[Bodhi]

Hazed, FYI, the Corsair has direct control linkage as well.... no wires for the control surfaces.  All big aluminum tubes with castings in the end.

[hazed-]

Originally posted by Bodhi
Hazed, FYI, the Corsair has direct control linkage as well.... no wires for the control surfaces.  All big aluminum tubes with castings in the end.

well thats good news in a way, at least its not just the 190 that has them.

I havent flown the f4u much so i wouldnt know if it has the right behaviour for this control method but if like they said on this programme they make a big difference then shouldnt both the 190and the f4u's feel more precise than other aircraft?

Does the F4u in AH also have the usual nose bounce/yaw as other aircraft?

I guess the feeling should be similar to a joystick with no damping vs one with it on.Any aircraft that has not got the rod actuated controls should always have that damping feeling to the controls, a slight delay to small movements of ailerons etc.The 190 and F4U's should be sharper and easier to control.

I think this sort of control would mean in a flip overthe top of a vertical climb the two aircraft should be easier to adjust than other wire controlled planes.Just as the modern stunt planes are good at accurate ACMs. I'd have to say the 190s do feel pretty good now but to a greater degree than any others in AH? im not so sure.Feels the same to me.

[MANDOBLE]

Originally posted by hazed-
"Once the controls were correctly balanced, it was important to ensure that they stayed that way over a wide range of speeds.A fighter pilot did not want to have to re-trim the aircraft each time he moved the throttle.The team were so successful in this that they found that movable trim tabs were unecessary.Small fixed trimming tabs were fitted to the ailerons, the elevators and the rudder."

AH 190S (any variant) are extremely unstable without being trimmed all the time.

[hazed-]

Originally posted by MANDOBLE
AH 190S (any variant) are extremely unstable without being trimmed all the time.

yup this is the sort of thing i tend to question about AH's 190s.

I must say when i get such limited reactions to what i post, like this bit of info it really dissapoints me. I would really appreciate some sort of explanation for the 190's present behaviour in ah.among other aircraft.
What i would truelly like to see is someone from HTC describing areas in the model where they feel they have it slightly wrong or that they intend to change.When pyro recently posted about roll rates etc I was very pleased.Its just since then Ive seen nothing to let us know if we have got the right idea about his request for snippets of info on all aircraft. I dont know if posting this stuff is a complete waste of my time.You feel the same mandoble?

[ccvi]

I think the only way to get a correct flight model would be if hitech sold is RV and got one of these...

http://www.flugwerk.de/new/fw190/fw190.shtm

to test (don't forget to add 1klbs for heavier engine and weapons) and then modeled it accordingly

[hitech]

Hazed just so you know, your way off base about cable V rod control. It comes down to more a feel than a control response.

There isn't any lag in cable control, it has much more to do with the presure and feel of the stick. Whats realy strange is that your asking us to model cable V rod control when we have an electronic joystick.

The stick you are using AH is no where near as precise as either cable or push rods.


HiTech

[MiloMorai]

Originally posted by hitech
Hazed just so you know, your way off base about cable V rod control. It comes down to more a feel than a control response.

There isn't any lag in cable control, it has much more to do with the presure and feel of the stick. Whats realy strange is that your asking us to model cable V rod control when we have an electronic joystick.

The stick you are using AH is no where near as precise as either cable or push rods.


HiTech

There is lag in cable control over rod control, as there is always some stretch in the cable.

[Bodhi]

Hitech,

FWIW, there is always going to be a tad bit of slop in cable controlled aircraft, as they have the tendency to stretch over time.  This is why I have to re-tension the cables every time I do an annual or otherwise on cable equipped aircraft.  I find that War Era aircraft especially stretch cables as they are generally heavier on the controls that say an RV or Sukoi.  

Now as to whether Hazed is correct about control response on say a cable equipped 109 vs a 190, I disagree somewhat, I feel it is always in the amount of throw, balance, and ease of use in the control surface as to what makes the aircraft react faster.  The reason control cables were deleted from corsairs in favor of control tubes is a simple matter of the ability to with stand more damage.  A bullet will pass through the tube rather than break it as to a bullet through wire, well, you are screwed, on both accounts of the control surface as they run in a loop configuration.  

Lastly, whether you should model it or not?  No, absolutely not, you are correct in that no joystick currently available will make a whim of difference if its modeled.  THe only aircraft that should have an advantage in the game on roll rate response, should be the 38L with it's boosted ailerons.   Thats a differnet matter entirely...

My .02

[MANDOBLE]

HiTech, the description of the problem is different, and is not  related to rod vs cables.

If someone design a control system (stick, transmission and control surfaces) that doesn't need trim, that means that control response is not dependent on trimming. In AH, 190s control response is fully dependent on trimming at any speed. So, when I trim my 190 fully nose down, pulling back the stick has little effect, pushing down the stick has great effect, and viceversa. Same for ailerons and rudder.

So, IMO, the lack of trims would mean that autotrim for speed / angle should not be possible and would need constant input from the pilot. But, on the other hand, control response would not be dependant on trim possitions.

[john9001]

i think the "nose bounce" in AH is do to pilot induced oscillation.

[AHGOD]

On another note the 190's do bounce.  I have just gotten used to it after flying it for awhile.

[hazed-]

Originally posted by hitech
Hazed just so you know, your way off base about cable V rod control. It comes down to more a feel than a control response.

There isn't any lag in cable control, it has much more to do with the presure and feel of the stick. Whats realy strange is that your asking us to model cable V rod control when we have an electronic joystick.

The stick you are using AH is no where near as precise as either cable or push rods.


HiTech

thanks for the reply hitech! I did think about this quite a bit before posting and i looked up several references to the control rod type control. All references to these types of systems mention that they produce a more precise response.

I did think about the fact that we can change our joysticks to almost any amount of damping and we have the deadband etc to adjust.Basically this means that if i want to i could set it up so that any aircraft has a terrible delay in the controls.
It is kinda a mute point due to the joysticks and how we set them up and i concede your point about this.
But if the control with wires and pulleys does indeed cause a slight delay in the response of the various controls should AH not impose a slightly higher MINIMUM damping level in the joystick setup?
If say damping runs from 0 to 100 the wire controled planes should have a minimum setting of say 10 imposed by the program whereas any aircraft with control rods can be set to 0 (or close) by the program.If this could be done automatically as you choose different planes in the background it will simulate this effect that has been explained.
This would result in a marked difference in the feel of wire controled planes vs the F4U and 190 (and any other that has them). It wont be much but it would at least be a step in the right direction dont you think?
Anyhow i guess you know whats possible or what you feel is worth doing but please dont discount the effect of control rods altogether.

I realise how we set up our joysticks can totally ruin all these types of control feelings and some wouldnt even notice it but it would still be a good thing to model i think.This may however make you prefe not to bother i dont know.

I posted what kurt tank said about the difference and as you can see Bohdi, a pilot who has to adjust this very thing knows what im getting at and agrees it should feel different for control rod vs wires. I hope others might be able to explain it further.The point is though, that i dont know what the difference should 'feel' like.It seems Bohdi does know and perhaps could give us a description of what the differences feel like? I just assumed it should be looked at.

HT if you feel its hardly worth the effort due to joystick limitations then fair enough   but i hope you will take a look into it a bit further just in case? , oh and thanks again for the reply.


P.S. could you please explain why the 190 needs so much trim when looking at the fact that the movable trim tabs were deemed unecessary by the designers. Shouldnt our AH 190 also display a similar lack of need for constant trimming?
It must effect the way it flies if it needs constant adjustment and that means its not behaving like the real one.
Again Im no expert but it does seem a bit off.

for instance: take a P51 or La7 or similar and climb on auto pilot alt X. Then smoothly level out manualy and roll to 80 degress so your wings are not level with horizon and hit auto level trim.Take a mental note of the time it takes to settle those trim bars and level the aircraft.

Then try the 190A5 or D9 and you will find it takes an absolute age to settle into level trim.This with an aircraft that has a very fast roll and should settle in roll quickly? Im a little dumbfounded by it Most other aircraft settle very quickly. The La7 is very fast.
The P47 also takes a fair bit of time to settle down on trim when its fully loaded and tends to see-saw around on auto.Yet the p38 and P51s with the same loadout are stable.Could you explain why this is ?

oh and if you want to see the slowest of them all try it with a 109! If you engage auto level when you are on your side you will fly for almost a minute! (ok slightly exagerated ) before you finally level out. It seems to be like its flying in a pot of glue

[funkedup]

Ya know if any of you would bother to pick up an elementary book on aeronautics and flight mechanics, all these apparent mysteries would become clear.