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PostPosted: Mon Oct 23, 2006 12:25 am 
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Joined: Wed Jul 27, 2005 2:15 am
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Hi all! I bought the FW package a month ago or so, and frankly speaking there're some issues I'm not too happy about:

* Is the tailwheel steering really linked to the throttle, or am I just missing something here? I went and dismantled the aircraft.cfg contact_points steering and put in differential braking instead, but it seems that the tailwheel steering STILL activates when the throttle is opened. Why is that?

* The Shockwave v1.0 was fully trimmable, whereas the original FWs had elevator trim only. OK, that was fixed later, so no harm done - but what does that tell about Shockwave's much-lauded "Absolute Realism" modelling process, i.e. shouldn't a basic historical limitation like this have been caught in the first version _already_ if this "Absolute Realism"-thingy really is what you claim it to be research-wise?

* The manual is decidedly weird at places. First it states that "this aircraft is equipped with a fully automatic mixture control", but later on in the checklist it instructs the pilot to "check the mixture control and set to rich" before landing! Now go and figure _that_ one out, esp. as the originals had a system called "kommandogerät" which was an automatic control system for many flight functions icluding fuel mix, prop pitch, spark advance, etc. and IIRC it only had two settings - automatic and emergency - for mixture!

* The manual states that "the Focke-Wulf 190 A-4, introduced during the summer of 1942, was essentially the same as the A-3, with the exception of uprated radio equipment and the addition of the MW50 methanol-water injection system". Some sources, however, say that the A-4 was never equipped with the MW50, and even Wikipedia says that "fittings for MW 50 first appeared on the BMW 801D in 1942, but it never went into production for this engine because the cylinder heads developed micro-cracks when MW 50 was used" and "although practically every production model 190 included the 801D engine, it was not until very late in the war that the MW50 kits were actually supplied and available"!

Any comments on these points of critique, dear ladies and gentlemen of Shockwave?


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PostPosted: Mon Oct 23, 2006 3:55 am 
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Airman First Class

Joined: Tue Jan 18, 2005 1:54 pm
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Wikipedia (as any source of information) is only as good as its own sources.
Wikipedia is often flawed, especially in details like this for which information is scarce and often contradictory.

As to having to set the mixture to rich manually when landing, that might be a restriction of FS. Check the default 737 for something similar. If you move the throttles down while autothrottle is enabled the maximum power available will decrease. I'd not be surprised if the same is true for mixture and prop pitch as well.


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PostPosted: Wed Oct 25, 2006 2:56 pm 
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Joined: Wed Jul 27, 2005 2:15 am
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Yeah, could very well be JWenting, but anyone from Shockwave care to comment on these findings still?


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PostPosted: Wed Oct 25, 2006 10:33 pm 
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A2A Major

Joined: Tue Jan 18, 2005 11:37 am
Posts: 461
msalama wrote:
* Is the tailwheel steering really linked to the throttle, or am I just missing something here? I went and dismantled the aircraft.cfg contact_points steering and put in differential braking instead, but it seems that the tailwheel steering STILL activates when the throttle is opened. Why is that?


There are a few things going on with this question. What you are experiencing when you give the plane a blast of throttle is not tailwheel steering, it is torque reaction and you will need to feed in a lot of right rudder to compensate.

Next, the aircraft was initially delivered to give some tailwheel steering. There are two reasons for this. First, many users don't have the full banana in terms of controllers (some even use the keyboard still - the boss is watching!). If you simply set the steering angle to 180 this provides a fully-castoring tailwheel that won't be steerable. We made a very conscious decision to do it this way. Secondly, FS9 does NOT have any realistic rudder response while the plane is on the runway and including a bit of tailwheel steering compensates for that issue. However as I mentioned, FSX has very good ground and near-ground flight dynamics so all tailwheel aircraft for that sim will be updated if they have not already. Differential braking is not set in the contact points section, only the steerability of the contact point. There is a separate section that deals with differential braking and that was already enabled.

msalama wrote:
* The Shockwave v1.0 was fully trimmable, whereas the original FWs had elevator trim only. OK, that was fixed later, so no harm done - but what does that tell about Shockwave's much-lauded "Absolute Realism" modelling process, i.e. shouldn't a basic historical limitation like this have been caught in the first version _already_ if this "Absolute Realism"-thingy really is what you claim it to be research-wise?


We explained our reasons for leaving the trim enabled. The aircraft itself had no trim control but using the keypress was left functional to simulate the trim setting of the bendable tab by the ground crew. Here is my response to that thread in case you did not find it:

"...the actual aircraft has no rudder or aileron trim in the cockpit. These were adjusted externally for proper aircraft trim by changing the rigging as required, similar to many training aircraft still in production. However, FS9 does make these available, so we are providing them, with this bit of artistic license taken on the basis that these could controls could have been adjusted on the ground by the crew chief per the pilot's requirements. As always, the checklist has been condensed and greatly simplified for FS9, with the inclusion of these features being a part of that process. Keep in mind, this would only be functional using keystrokes or joystick buttons, at the user's option. The cockpit itself does not have these controls and is accurately depicted."

So, to simplify, trim WAS possible but done on the ground. So how was it "inaccurate" to have this enabled as described? Maybe a flip of the coin in terms of whether someone would want it there or not, but if you want to fly the plane realistically but wish to adjust the trim to suit a particular loadout, such as with a drop tank, you can do this with the trim control and then IGNORE the trim whilst flying the plane.

I think this was explained in some detail and the explanation should suffice as-is.

msalama wrote:
* The manual is decidedly weird at places. First it states that "this aircraft is equipped with a fully automatic mixture control", but later on in the checklist it instructs the pilot to "check the mixture control and set to rich" before landing! Now go and figure _that_ one out, esp. as the originals had a system called "kommandogerät" which was an automatic control system for many flight functions icluding fuel mix, prop pitch, spark advance, etc. and IIRC it only had two settings - automatic and emergency - for mixture!


The manual instruction for the mixture control position is entirely appropriate. Yes, we know how the system works in the real plane; however FS9 does not duplicate the kommandogerat system. It is either fully manual or fully automatic. Were you aware, however, that even with the mixture control set to "auto" in the flight model, the mixture lever axis on your joystick will STILL cut off the mixture if you set it to OFF or 0 percent? It is always standard procedure in any piston airplane to check the position of the mixture control before landing to make sure it is correct. The manual simply reminds the pilot to do this very important thing. In FS, it is possible to load a flight and begin flying a plane with the mixture control axis set to OFF; the plane will fly just fine until the control axis is even slightly disturbed, and then the engine will cut out because the sim sees a new value for the mixture, namely, cutoff. There was thread about this very phenomenon at the SOH a while back and it took the guy days to figure out what had happened. Point is you ALWAYS check the mixture control before landing. In a plane with automixture, you just set it to fully rich all the time and double-check it before landing or taking off.

msalama wrote:
* The manual states that "the Focke-Wulf 190 A-4, introduced during the summer of 1942, was essentially the same as the A-3, with the exception of uprated radio equipment and the addition of the MW50 methanol-water injection system". Some sources, however, say that the A-4 was never equipped with the MW50, and even Wikipedia says that "fittings for MW 50 first appeared on the BMW 801D in 1942, but it never went into production for this engine because the cylinder heads developed micro-cracks when MW 50 was used" and "although practically every production model 190 included the 801D engine, it was not until very late in the war that the MW50 kits were actually supplied and available"!


We didn't use Wikipedia as a source. We used actual test data from Focke-Wulf, which is generally regarded as a more accurate resource than Wikipedia. We also used two published volumes, "German Airplanes of WWII" by Chris Chant, and "German Aircraft of the Second World War" by Antony L. Kay and J. R. Smith, both of which stated that the A-4 was equipped with the 801D-2 engine and was thus capable of utilizing the MW50. Whether or not all serial numbers of the aircraft in any particular production run were equipped with MW50 is unknown. We chose to assume for our purposes that the MW50 was available for the plane we modeled. There is ample evidence that it was indeed available, contrary to Wikipedia.


Last edited by SD_Research on Sat Nov 25, 2006 3:30 am, edited 1 time in total.

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PostPosted: Thu Oct 26, 2006 1:47 am 
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Airman

Joined: Wed Jul 27, 2005 2:15 am
Posts: 40
Quote:
What you are experiencing when you give the plane a blast of throttle is not tailwheel steering, it is torque reaction and you will need to feed in a lot of right rudder to compensate.


I wasn't talking about torque, which of course should be strong in a high-powered warbird like the FW. It just feels that there's a steering trigger of some kind somewhere in the FM which suddendly activates whenever one opens up the throttle - but OK, since there isn't (why the hell should there be?) then what causes this has to be the increased prop airflow over the tail. And nothing wrong with that otherwise, but the effect feels a bit too strong and abrupt to me, just as if the bird - heavy as she is - was devoid of any mass / inertia resisting the steering!

But then again all this is a bit subjective - and yes, indeed, controller-dependent too - so let's let that be. And maybe the real bird had a very effective rudder as well? It's just that she feels a bit squirrely on the ground to me, that's all...

As for your other answers: OK, explains your motives, and I can see the whys and wherefores behind these decisions now - though the MW50 question is to my understanding still debated even in circles outside the all-knowing and venerable Wikipedia :wink: So thank you for answering!


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PostPosted: Thu Oct 26, 2006 9:53 am 
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A2A Major

Joined: Tue Jan 18, 2005 11:37 am
Posts: 461
msalama wrote:
Quote:
What you are experiencing when you give the plane a blast of throttle is not tailwheel steering, it is torque reaction and you will need to feed in a lot of right rudder to compensate.


I wasn't talking about torque, which of course should be strong in a high-powered warbird like the FW. It just feels that there's a steering trigger of some kind somewhere in the FM which suddendly activates whenever one opens up the throttle - but OK, since there isn't (why the hell should there be?) then what causes this has to be the increased prop airflow over the tail. And nothing wrong with that otherwise, but the effect feels a bit too strong and abrupt to me, just as if the bird - heavy as she is - was devoid of any mass / inertia resisting the steering!

But then again all this is a bit subjective - and yes, indeed, controller-dependent too - so let's let that be. And maybe the real bird had a very effective rudder as well? It's just that she feels a bit squirrely on the ground to me, that's all...

As for your other answers: OK, explains your motives, and I can see the whys and wherefores behind these decisions now - though the MW50 question is to my understanding still debated even in circles outside the all-knowing and venerable Wikipedia :wink: So thank you for answering!


Yes, you have it right, the plane is very squirrely on the ground! You really just need to "ease..." on the power for takeoff and taxying. Now go complete your mission, sir.


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