Big LASTE IFFCC Bug

[amalahama]

In fact, things don't have to 'necessarily' move in the same direction as wind if they spin... A good football fan would know that :)

 

Regards!

[Sierra99]

I dont unfortunately, but I think it is enough that we all agree that there is a bug so the ED team is able to go for a fix.

 

It is important that ED see an agreement on a bug thread.

 

Consensus is not an indication of a problem. You believe there is a bug based on what I consider inconclusive testing. In my opinion, inputting a wind component where no wind is present simply confuses the issue. The IFCC System draws information from MANY different aircraft systems to provide its final aiming cues. (CADC, EGI CDU and numerous other places"

 

Also there is this:

" Model mode LSK

 

Allows the selection of the wind and temperature model mode that will be used by IFFCC in its ballistic calculations.There are four possible model modes. Depressing this LSK steps through the model modes described below:

 

1. BOTH -Indicates that both the wind and temperature values displayed on this page will be used by IFFCC.

2. WIND - Indicates that only the wind values displayed on this page will be used by IFFCC. 3. TEMP - Indicates that only the temperature values displayed on this page will be used by IFFCC.

4. NONE - Indicates that neither the wind or temperatures values displayed on this page will be used by IFFCC. NOTE

 

If no profile has been entered or uploaded from the DTS, none is the default model selection."

 

(Not gonna cut and paste pages but I'm looking at a current A-10C Dash 1.)

 

Without knowing exactly what and how the systems are modeled in the game, you have no way of knowing your tests prove anything.:noexpression:

[Joni]

Consensus is not an indication of a problem. You believe there is a bug based on what I consider inconclusive testing. In my opinion, inputting a wind component where no wind is present simply confuses the issue. The IFCC System draws information from MANY different aircraft systems to provide its final aiming cues. (CADC, EGI CDU and numerous other places"

 

Also there is this:

" Model mode LSK

 

Allows the selection of the wind and temperature model mode that will be used by IFFCC in its ballistic calculations.There are four possible model modes. Depressing this LSK steps through the model modes described below:

 

1. BOTH -Indicates that both the wind and temperature values displayed on this page will be used by IFFCC.

2. WIND - Indicates that only the wind values displayed on this page will be used by IFFCC. 3. TEMP - Indicates that only the temperature values displayed on this page will be used by IFFCC.

4. NONE - Indicates that neither the wind or temperatures values displayed on this page will be used by IFFCC. NOTE

 

If no profile has been entered or uploaded from the DTS, none is the default model selection."

 

(Not gonna cut and paste pages but I'm looking at a current A-10C Dash 1.)

 

Without knowing exactly what and how the systems are modeled in the game, you have no way of knowing your tests prove anything.:noexpression:

 

 

Still havent read the whole thread, right?

 

Thanks for your input.

[sgtmike74]

Could it be that the Rocket Piper is aiming into the wind because it is calculating the rockets weather cocking into the wind. So, if a strong wind is coming in from the left the rockets will steer left into the wind due to the effects on the fins?

 

I did a quick google search and this popped up.

http://www.grc.nasa.gov/WWW/k-12/rocket/rktcock.html

 

Pretty interesting stuff, and interesting thread.

[Joni]

Mmmm, that's indeed interesting!!

 

 

I think it could be possible, but the rocket will still land to the right because wind is just an air mass displacing. So the rocket which is flying inside that air mass moving to the right (wind coming from the left) will be displaced too and will eventually land to the right.

 

 

Sorry to bring this complicated stuff, it's a pilot thing =S

[Flagrum]

Mmmm, that's indeed interesting!!

 

 

I think it could be possible, but the rocket will still land to the right because wind is just an air mass displacing. So the rocket which is flying inside that air mass moving to the right (wind coming from the left) will be displaced too and will eventually land to the right.

 

 

Sorry to bring this complicated stuff, it's a pilot thing =S

Wouldn't that depend on wether it's engine is still running or not?

 

edit: or maybe more precise, depending on the total energy (initial / launching platform and rocket motor) that is directed with that angle into the wind, compared to the forces/energy the cross wind can excert onto the rocket?

Edited August 28, 2015 by Flagrum

[Hansolo]

Could it be that the Rocket Piper is aiming into the wind because it is calculating the rockets weather cocking into the wind. So, if a strong wind is coming in from the left the rockets will steer left into the wind due to the effects on the fins?

 

I did a quick google search and this popped up.

http://www.grc.nasa.gov/WWW/k-12/rocket/rktcock.html

 

Pretty interesting stuff, and interesting thread.

Ah I guess that was also what Flagrum was hinting in #11. Didn't really get it. Interesting read though. Thanks for sharing

 

Wouldn't that depend on wether it's engine is still running or not?

 

edit: or maybe more precise, depending on the total energy (initial / launching platform and rocket motor) that is directed with that angle into the wind, compared to the forces/energy the cross wind can excert onto the rocket?

Sounds reasonable. Could be that the rocket might still have enough forward momentum to the left which is greater than the wind until impact.

 

Cheers

Hans

[Joni]

Wouldn't that depend on wether it's engine is still running or not?

 

edit: or maybe more precise, depending on the total energy (initial / launching platform and rocket motor) that is directed with that angle into the wind, compared to the forces/energy the cross wind can excert onto the rocket?

 

No, why would you say that? Anything inside an air mass without being influenced by friction (something on the ground) will be displaced along with the air mass.

[Joni]

Ah I guess that was also what Flagrum was hinting in #11. Didn't really get it. Interesting read though. Thanks for sharing

 

 

Sounds reasonable. Could be that the rocket might still have enough forward momentum to the left which is greater than the wind until impact.

 

Cheers

Hans

 

No, wind is not something that blows! Wind is just an air mass that is moving and people and things get the feeling that something is blowing when the air mass moves "through" the object (thats why we call it "blows to"), but thats not how it works.

 

If all of this would make sense, then the bullets reticle should be even more to the left than the rocket piper.

[Flagrum]

No, why would you say that? Anything inside an air mass without being influenced by friction (something on the ground) will be displaced along with the air mass.

Huh? Friction (with the ground) is not the only counter force of the wind. Our rocket has also thrust (directed slightly into the wind) and inertia, which makes objects resist the displacing when moving through the air.

 

edit: if free moving objects would only be displaced by the moving air mass, then you could not throw a stone into the wind ... and expect it to land in front of you (as opposed to be moved by the air mass to somewhere behind you). ;o)

Edited August 28, 2015 by Flagrum

[Joni]

Huh? Friction (with the ground) is not the only counter force of the wind. Our rocket has also thrust (directed slightly into the wind) and inertia, which makes objects resist the displacing when moving through the air.

 

 

Yes, so? Dont see the point of that sorry mate.

 

I was leading the comment into the fact that what you said will never make the trajectory of the rocket go to the opposite direction of the direction which the wind is going to.

[Joni]

About your EDIT: Yes that is correct. But I was going somewhere else with my statement.

[Joni]

Im sensing that this thread is going to "lets find an explanation why this is not a bug" :(

 

Much fo what you say is absolutely true, but will never make the solution to behave like this!

[Flagrum]

Yes, so? Dont see the point of that sorry mate.

 

I was leading the comment into the fact that what you said will never make the trajectory of the rocket go to the opposite direction of the direction which the wind is going to.

See the link about the weather cock effect - the rocket yaws into the wind. Now add the initial speed and the rocket motor thrust and you have a rocket that is moving into the wind. Depending on the angle that weather cock effect results in, that can be enough to overcome the displacement of the rocket by the moving air mass and make the rocket fly somewhere to the side where the wind comes from.

 

About your EDIT: Yes that is correct. But I was going somewhere else with my statement.

Now you're confusing me ... what exactly is correct?

 

Im sensing that this thread is going to "lets find an explanation why this is not a bug" :(

 

Much fo what you say is absolutely true, but will never make the solution to behave like this!

This thread is to examine the situation - so we can understand if the issue is really a bug or not.

 

For that we need to find all relevant factors...

[Joni]

See the link about the weather cock effect - the rocket yaws into the wind. Now add the initial speed and the rocket motor thrust and you have a rocket that is moving into the wind. Depending on the angle that weather cock effect results in, that can be enough to overcome the displacement of the rocket by the moving air mass and make the rocket fly somewhere to the side where the wind comes from.

 

 

Now you're confusing me ... what exactly is correct?

 

 

This thread is to examine the situation - so we can understand if the issue is really a bug or not.

 

For that we need to find all relevant factors...

 

OK, I guess I am too anxious to see this fixed, I dont know. The behaviour of the solutions seems so much wrong to me that is driving me crazy to the point I dont want to fly the A10 :doh: I know is too exagerated but that's me.

 

 

Cheers.

[Flagrum]

OK, I guess I am too anxious to see this fixed, I dont know. The behaviour of the solutions seems so much wrong to me that is driving me crazy to the point I dont want to fly the A10 :doh: I know is too exagerated but that's me.

 

 

Cheers.

The funny(?) thing is, when I - admittedly very briefly - did a rocket run in heavy cross wind, the rockets actually hit where the pipper predicted it.

 

So IF there is a bug, then it is not a IFFCC/HUD bug, but a physics sim bug.

[Joni]

Nice. It would be so much valuable to have someone from ED confirming how it was coded so we can all rest at night (or perhaps just me).

[jweisner]

Depending on the angle that weather cock effect results in, that can be enough to overcome the displacement of the rocket by the moving air mass and make the rocket fly somewhere to the side where the wind comes from.

 

FFAR rockets like the MK-151 are spin-stabilized, aren't they? Wouldn't this help to negate weather cocking?

[DirtyFret]

Well this got interesting.

 

If someone is in doubt about the validity of Pistons claim I would politely encourage them to watch the tracks I posted with actual the inconsistent cue behaviour and no weather/wind cockng of the rockets into the wind. The rockets deviate into the same direction as the MK82 and 30mm shells.

 

The tracks show:

 

The M151 rockets being affected by the wind in the same direction as other munitions

The RKT cue behaving erratically; intermittenly correcting to the right and then suddenly to the left

 

 

In my humble opinion there is little doubt that there is fault somewhere in the RKT wind correction. I have not been able to reproduce this bug in CCIP Bombing nor GUN mode( in other they work fine for me).

Edited August 28, 2015 by DirtyFret

[Sierra99]

Still havent read the whole thread, right?

 

Thanks for your input.

 

Actually...I have and I stand by my original statement. You are convinced there is an error...I'm not. I see differences in aimpoint and impact point yes...but the list of things this could be attributed to that aren't a "Big LASTE IFFCC BUG" is extensive depending on how all of this is modeled by ED.

 

Since you seem intent on identifying a bug I'll leave you to it...I'd recommend finding a real -1 and -34 so you can see how the real aircraft is supposed to work and compare it to the sim.

Edited August 29, 2015 by Sierra99

[Sierra99]

Well this got interesting.

 

If someone is in doubt about the validity of Pistons claim I would politely encourage them to watch the tracks I posted with actual the inconsistent cue behavior and no weather/wind cocking of the rockets into the wind. The rockets deviate into the same direction as the MK82 and 30mm shells.

 

I watched the tracks and agree...there is odd behavior. However, there is simply no way of knowing what is causing it. You can ASSUME its an IFFCC problem...but there are too many variables to make that determination with any sort of credibility. You can ASSUME its a LASTE problem...But again you don't have enough information to to state that with any level of certainty or credibility.

 

In my humble opinion there is little doubt that there is fault somewhere in the RKT wind correction. I have not been able to reproduce this bug in CCIP Bombing nor GUN mode( in other they work fine for me).

 

Again...an assumption. Is it a Rocket Wind correction issue? Or is the CADC providing inaccurate information? Is the IFFCC using the wrong winds? Or is the HUD displaying the information incorrectly? These are the things that can happen in real life...If all of the systems that tie together to enable the LASTE system to operate are modeled accurately by ED it would stand to reason they could happen in the sim too.

 

The BEST thing to do would be say "HEY ED, we see odd behavior...Here are the tracks displaying the odd behavior..." and let ED figure out IF there is a problem verses jumping to conclusions and declaring something is a bug when you really don't have enough information to make that statement.

[PFunk1606688187]

OK, I guess I am too anxious to see this fixed, I dont know. The behaviour of the solutions seems so much wrong to me that is driving me crazy to the point I dont want to fly the A10 :doh: I know is too exagerated but that's me.

 

 

Cheers.

 

If this is enough to make you not want to fly the A-10 then you should quit while you're ahead. There are enough things undermodeled, poorly modeled, incorrectly modeled in the module to send an OCD realism nerd into a seizure. Most don't directly impact the use of the aircraft as intended, merely make you augment how you do it differently to real life. Something like this could rate high enough on the scale to make them actually fix it (A-10 bug fixes over the last 2 years have been few and far between with the last being I think a year ago or more).

 

As for testing this, well we need to go beyond speculation. Someone needs to actually try to use the LASTE wind correction in an extant and accurately measured wind with rockets and test its effects to see if the rocket behaves in a manner consistent with the prediction. Without that you're not likely to get a response from ED.

[DirtyFret]

I watched the tracks and agree...there is odd behavior. However, there is simply no way of knowing what is causing it. You can ASSUME its an IFFCC problem...but there are too many variables to make that determination with any sort of credibility. You can ASSUME its a LASTE problem...But again you don't have enough information to to state that with any level of certainty or credibility.

 

 

 

Again...an assumption. Is it a Rocket Wind correction issue? Or is the CADC providing inaccurate information? Is the IFFCC using the wrong winds? Or is the HUD displaying the information incorrectly? These are the things that can happen in real life...If all of the systems that tie together to enable the LASTE system to operate are modeled accurately by ED it would stand to reason they could happen in the sim [...]

 

Thank you for taking the time and watching them. :thumbup:

 

I 100% agree with you, without extensive testing there is no way of knowing why this odd behavior is seen and what is the cause.

 

[...]

The BEST thing to do would be say "HEY ED, we see odd behavior...Here are the tracks displaying the odd behavior..." and let ED figure out IF there is a problem verses jumping to conclusions and declaring something is a bug when you really don't have enough information to make that statement.

 

This exactly what I was hoping I have done with the .trk files and the vids I posted earlier.:smilewink:

Edited August 29, 2015 by DirtyFret

[Joni]

Agreed. Let's see if ED see this thread in the upcoming months.

Edited August 30, 2015 by JohnnyQ

[chaos]

It'd be nice to get a response from ED. Something to the effect of "we're looking into this issue... more to follow".

 

I agree with one of the posters that a lot of things are not accurately modeled... however, they're usually things that don't impact gameplay directly. Incorrectly aiming rockets would not qualify IMHO...