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Thanks toten. The thing is that i am a real life profissional pilot and the a320 compensates for the wind when tracking a VOR course. The dc6 probably does not (old AP) and does not have an airdata computer to know wind speed and direction. I just wanted to make sure that it wasnt my simulator bugging. By the way you also experienced this?

 

Many thanks in advance

6 hours ago, randomTOTEN said:

Mike that sounds like normal behavior for VOR tracking.

 

Robert Toten

 

Edited by MikeTheAviator

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On 6/12/2019 at 8:21 PM, MikeTheAviator said:

and the a320 compensates for the wind when tracking a VOR course

Right, but it is from an entirely different era of technology.

On 6/12/2019 at 8:21 PM, MikeTheAviator said:

By the way you also experienced this?

I don't, but from what I remember, Opus causes some weird issues in the sim, wind-wise.


Kyle Rodgers

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There is absolutely no reason why the real aircraft wanders around a VOR track, unless the VOR is just about out of range.  The autopilot had 'Range Data Smoothing' in order to stop any wandering, and it did a good job.  As far as needing an FMS for wind speed, rubbish.  The VOR signal causes the aircraft to move further right or left the moment it starts to deviate from the centreline, and it doesn't care what the wind is, as long as it is not a rediculous speed.  Phil McConnell


Phil McConnell

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On 6/14/2019 at 3:18 PM, philfab2 said:

There is absolutely no reason why the real aircraft wanders around a VOR track, unless the VOR is just about out of range.  The autopilot had 'Range Data Smoothing' in order to stop any wandering, and it did a good job.  As far as needing an FMS for wind speed, rubbish.  The VOR signal causes the aircraft to move further right or left the moment it starts to deviate from the centreline, and it doesn't care what the wind is, as long as it is not a rediculous speed.  Phil McConnell

Ifigured that too. Probably a bug in my sim. I think this airplane is perfectly capable of dealing with a 40kt crosswind at cruise speed. 

I just think pmdgs products are too expensive to have these types of problems.

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9 hours ago, MikeTheAviator said:

I just think pmdgs products are too expensive to have these types of problems.

This is really, incredibly unfair.

While I understand that line of logic, it falls apart entirely when you go deeper than surface level.

 

I have a computer that I built at home for around $8000 - custom all of the things that I designed myself, purchased myself, put together myself, and maintain myself. I could knock over a $0 glass of water and cause all kinds of problems for an $8000 computer. Nothing is ever "too expensive" to have a simple problem, caused by an externality. We in aviation know this incredibly well as "pilot [or human] error." A 757 was brought down years back because someone put tape over a static port while washing it and forgot to take it off. All kinds of emergent technology, for a cool $65M, brought down by a piece of tape and the human condition (both forgetfulness and failing to piece together that the other guy's instruments were fine).

Similarly, you can take a free weather program that chucks all kinds of out of tolerance variables and have it cause aircraft to misbehave - doesn't matter if you downloaded it off of AVSIM as a free add-on, or paid $1000 for it. If the weather program is feeding the sim (and therefore the plane) bad data, there really isn't too much we can do. The more complex and realistic you make a plane, the more susceptible you make it to misbehaving when programs throw in bad data.

NOTE!

I am not saying "Opus is bad" or "all weather programs are bad" (in fact, my weather program of choice has a rep for causing all kinds of weird issues if you leave the turbulence scalar too high). I'm saying bad data can cause issues. Interestingly, turbulence isn't really modeled in the sim, in a natural way. In reality, it is more of a feeling than a visible thing. Since we can't "feel" the sim, MS took turbulence and made us "feel" it by using visuals, created by beating the plane around. Because a realistic amount of shake would be too subtle, they shake the plane around quite a lot. Weather add-on devs followed suit.

The result is something on the magnitude of 6+ g swings, in just about all directions. You really aren't going to find any APs out there that will handle that gracefully, while also being realistically precise. The additional problem is that this is made worse by the momentary nature of the spikes. Air is actually fluid in how it behaves (in the sense that we can use computational fluid dynamics to model it). Even when we have the most violent rotors (in standing mountain waves and other situations), you will never see that kind of swing. The magnitude of the swing might be that high, but it is not as violent/sudden, as the fluid of one "segment" of air will affect the other on its boundary, spreading it out over time.

...hell, a KAP150's default mode in NAV (VOR or GPS) is to hunt - forever - even in calm wind.

 

 

The solution is to provide the sim with realistic data. This is done by dialing down the turbulence that the weather add-on is injecting into the sim. If the expectation is realism, then realism should be expected on all fronts - to include the weather guys.

[Note: This is shown visually/graphically in a test we conducted in our 777 Intro document, and later in the 747 docs, if you have either of those products.]

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Kyle Rodgers

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Scandinavian, i did not mear to offend anyone at pmdg. I tried with opus turned off and i still get the aircraft wandering arround the radial

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4 hours ago, scandinavian13 said:

This is really, incredibly unfair.

While I understand that line of logic, it falls apart entirely when you go deeper than surface level.

 

I have a computer that I built at home for around $8000 - custom all of the things that I designed myself, purchased myself, put together myself, and maintain myself. I could knock over a $0 glass of water and cause all kinds of problems for an $8000 computer. Nothing is ever "too expensive" to have a simple problem, caused by an externality. We in aviation know this incredibly well as "pilot [or human] error." A 757 was brought down years back because someone put tape over a static port while washing it and forgot to take it off. All kinds of emergent technology, for a cool $65M, brought down by a piece of tape and the human condition (both forgetfulness and failing to piece together that the other guy's instruments were fine).

Similarly, you can take a free weather program that chucks all kinds of out of tolerance variables and have it cause aircraft to misbehave - doesn't matter if you downloaded it off of AVSIM as a free add-on, or paid $1000 for it. If the weather program is feeding the sim (and therefore the plane) bad data, there really isn't too much we can do. The more complex and realistic you make a plane, the more susceptible you make it to misbehaving when programs throw in bad data.

NOTE!

I am not saying "Opus is bad" or "all weather programs are bad" (in fact, my weather program of choice has a rep for causing all kinds of weird issues if you leave the turbulence scalar too high). I'm saying bad data can cause issues. Interestingly, turbulence isn't really modeled in the sim, in a natural way. In reality, it is more of a feeling than a visible thing. Since we can't "feel" the sim, MS took turbulence and made us "feel" it by using visuals, created by beating the plane around. Because a realistic amount of shake would be too subtle, they shake the plane around quite a lot. Weather add-on devs followed suit.

The result is something on the magnitude of 6+ g swings, in just about all directions. You really aren't going to find any APs out there that will handle that gracefully, while also being realistically precise. The additional problem is that this is made worse by the momentary nature of the spikes. Air is actually fluid in how it behaves (in the sense that we can use computational fluid dynamics to model it). Even when we have the most violent rotors (in standing mountain waves and other situations), you will never see that kind of swing. The magnitude of the swing might be that high, but it is not as violent/sudden, as the fluid of one "segment" of air will affect the other on its boundary, spreading it out over time.

...hell, a KAP150's default mode in NAV (VOR or GPS) is to hunt - forever - even in calm wind.

 

 

The solution is to provide the sim with realistic data. This is done by dialing down the turbulence that the weather add-on is injecting into the sim. If the expectation is realism, then realism should be expected on all fronts - to include the weather guys.

[Note: This is shown visually/graphically in a test we conducted in our 777 Intro document, and later in the 747 docs, if you have either of those products.]

Whereas with the gps it flies perfectly straight

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I fly the PMDG C-118 and have no trouble tracking a VOR radial.  Once on track, it stays there.  In fact, I flew thru a Active Sky 2016 generated thunderstorm between Pendleton, Oregon and Baker, Oregon and the AP continued to track properly even though the plane was being tossed all over the place.  In the real world, a 180° turn would have been in order but the Active Sky alert arrived after I had started my penetration.  

The only problem I have with the VOR is trying to figure out which course heading to fly, the one shown on the flight plan generated by FlightSim Commander, PFPX, FSTramp or the actual Sectional chart.  In any event, what ever course finally ends up at the VOR.

Jim Driskell


Boeing777_Banner_Pilot.jpg

James M Driskell, Maj USMC (Ret)

 

 

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3 hours ago, MikeTheAviator said:

Scandinavian, i did not mear to offend anyone at pmdg. I tried with opus turned off and i still get the aircraft wandering arround the radial

 

7 hours ago, scandinavian13 said:

This is really, incredibly unfair.

While I understand that line of logic, it falls apart entirely when you go deeper than surface level.

 

I have a computer that I built at home for around $8000 - custom all of the things that I designed myself, purchased myself, put together myself, and maintain myself. I could knock over a $0 glass of water and cause all kinds of problems for an $8000 computer. Nothing is ever "too expensive" to have a simple problem, caused by an externality. We in aviation know this incredibly well as "pilot [or human] error." A 757 was brought down years back because someone put tape over a static port while washing it and forgot to take it off. All kinds of emergent technology, for a cool $65M, brought down by a piece of tape and the human condition (both forgetfulness and failing to piece together that the other guy's instruments were fine).

Similarly, you can take a free weather program that chucks all kinds of out of tolerance variables and have it cause aircraft to misbehave - doesn't matter if you downloaded it off of AVSIM as a free add-on, or paid $1000 for it. If the weather program is feeding the sim (and therefore the plane) bad data, there really isn't too much we can do. The more complex and realistic you make a plane, the more susceptible you make it to misbehaving when programs throw in bad data.

NOTE!

I am not saying "Opus is bad" or "all weather programs are bad" (in fact, my weather program of choice has a rep for causing all kinds of weird issues if you leave the turbulence scalar too high). I'm saying bad data can cause issues. Interestingly, turbulence isn't really modeled in the sim, in a natural way. In reality, it is more of a feeling than a visible thing. Since we can't "feel" the sim, MS took turbulence and made us "feel" it by using visuals, created by beating the plane around. Because a realistic amount of shake would be too subtle, they shake the plane around quite a lot. Weather add-on devs followed suit.

The result is something on the magnitude of 6+ g swings, in just about all directions. You really aren't going to find any APs out there that will handle that gracefully, while also being realistically precise. The additional problem is that this is made worse by the momentary nature of the spikes. Air is actually fluid in how it behaves (in the sense that we can use computational fluid dynamics to model it). Even when we have the most violent rotors (in standing mountain waves and other situations), you will never see that kind of swing. The magnitude of the swing might be that high, but it is not as violent/sudden, as the fluid of one "segment" of air will affect the other on its boundary, spreading it out over time.

...hell, a KAP150's default mode in NAV (VOR or GPS) is to hunt - forever - even in calm wind.

 

 

The solution is to provide the sim with realistic data. This is done by dialing down the turbulence that the weather add-on is injecting into the sim. If the expectation is realism, then realism should be expected on all fronts - to include the weather guys.

[Note: This is shown visually/graphically in a test we conducted in our 777 Intro document, and later in the 747 docs, if you have either of those products.]

Found this in an autopilot forum.

Can this be the explanation? Please if anyone notices this “s-shaped” behavior while tracking a vor radial with the dc6 let me know.

 

here it goes 

Autopilots have been around for a while now.  Amazingly, the first aircraft autopilot was developed by Sperry Corporation in 1912!  I seem to have missed the hundreth birthday of the autopilot somehow.
Two decades ago the autopilots on most airplanes still weren't all that hot. They could hold a heading and altitude pretty good, and track an ILS when things were tight. Tracking a VOR radial was like doing S-turns down the airway. The button for airspeed/mach hold looked better than it worked”

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Kyle, my bad and for that i apologize. It Was becoming so  frustrating because i really love the aircraft and studied it so deeply 

 

apparently i needed to update my dc6 via OC. Testing now. So far so good.

 

Mike Simms

 

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11 hours ago, MikeTheAviator said:

Kyle, my bad and for that i apologize. It Was becoming so  frustrating because i really love the aircraft and studied it so deeply 

No need to apologize. I was going after the point, and not you. I even granted that I could see why you initially had that thought, but had you taken a moment to follow the line of thought, you would have likely, similarly, found it illogical.

People are prone to trying to prove their feelings with logic - it's human nature. I just felt like it needed to be addressed since people try to argue that point so often.


Kyle Rodgers

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