Help and Support Forums => Help and Training => Topic started by: Dobs on September 29, 2016, 11:08:52 AM
Title: Tracer smoke moves wrong way in turn fight
Post by: Dobs on September 29, 2016, 11:08:52 AM
See attached picture.
And along these lines...how many rounds are between tracers? Tracer every 15th round?
Also do the guns on the 38 fire, 1,2, 3, 4, cannon, 1,2,3,4, cannon? It appears they do with some sort of ms delay in them...
If they do, maybe that needs to be changed to 1/2, 3/4 for the MGs...firing only 1 gun at a time is a bit of neutering vs a maneuvering target.
Title: Re: Tracer smoke moves wrong way in turn fight
Post by: hitech on September 29, 2016, 12:01:24 PM
Tracers trails are correct. Because your nose is pointed above your flight trajectory when pulling G's (I.E AOA) your shooting to the inside of your circle and as the plane goes around the circle the tracer trail goes above you and then you fly back threw it.
Most tracers are set 4 to 1 I.E. 1 tracer round in 5 bullets.
Cannons and mg's are synced separately.
HiTech
Title: Re: Tracer smoke moves wrong way in turn fight
Post by: Dobs on September 29, 2016, 02:05:35 PM
Think I'm going to have disagree with that... I know what you are saying...AOA is difference between Velocity vector and nose
What you are saying is velocity vector is different than sight line (pipper) in the game?
If I am turning, and I have 10 degrees of AOA, am I mushing through the air, or am I "carving cleanly"....if I am mushing then I agree. If I'm carving, then I disagree...its like the guns are upcanted quite abit.
I tried to diagram difference in views of the flight path....mine is firing down the velocity vector...yours has quite a difference between velocity vector and the nose. See attachment...
Hard to find WWII footage where they are shooting with tracers under G...most are bounces and they are at 1 G.
Here is a clip (2:23 mark if clip doesn't take you to it).
Shows traces visible at a bomber...but he is shooting under G.
In this clip you can see tracer smoke from the P-51 under G as well... Hope the time reference urls work (if not it is 2:57 mark).
Title: Re: Tracer smoke moves wrong way in turn fight
Post by: FLS on September 29, 2016, 02:13:53 PM
Try AH film. Fly a tight turn shooting. Use trails and the F5 view looking down on your turn circle.
Title: Re: Tracer smoke moves wrong way in turn fight
Post by: Dobs on September 29, 2016, 03:01:16 PM
Sorry forgot to link it... film file I used to do what you just described.
I noticed that you weren't doing the test I described. It's easier to see the tracer smoke when you shoot.
Title: Re: Tracer smoke moves wrong way in turn fight
Post by: hitech on September 29, 2016, 06:34:42 PM
Simply by definition aoa is exactly the same as mushing
Title: Re: Tracer smoke moves wrong way in turn fight
Post by: Dobs on September 29, 2016, 06:52:54 PM
Here ya go...
Correct title should be: Tracers appear above the P-38 canopy bow when shooting.... AHF here: https://drive.google.com/file/d/0B-kwhapBgCtYb2RaLXJRSHptWDQ/view?usp=sharing (https://drive.google.com/file/d/0B-kwhapBgCtYb2RaLXJRSHptWDQ/view?usp=sharing)
As seen in the videos, and as seen in this video...
Spit XVI did not have this issue...maybe a simple X, Y, Z issue for tracer origination for 38s.
Dobs
Title: Re: Tracer smoke moves wrong way in turn fight
Post by: Dobs on September 29, 2016, 07:00:45 PM
I'm not sure I want to engage in angle of incidence, angle of attack, and nose vs velocity vector. See post above....
Title: Re: Tracer smoke moves wrong way in turn fight
Post by: FLS on September 29, 2016, 07:54:45 PM
Fly the test I described in the P-38 and shoot this time. You'll see what Hitech was telling you.
Title: Re: Tracer smoke moves wrong way in turn fight
Post by: Dobs on September 29, 2016, 09:05:22 PM
Fly the test I described in the P-38 and shoot this time. You'll see what Hitech was telling you.
Try watching the last film before you repeat yourself....
Title: Re: Tracer smoke moves wrong way in turn fight
Post by: EskimoJoe on September 29, 2016, 09:48:38 PM
Yeah, that does seem really weird to me. It appears almost as if the smoke trails are originating from above your cockpit. I couldn't tell you about the science behind that, but it really doesn't seem logical to me, even with the explanation of shooting inside your circle and such.
It's either witchcraft, or there is a complicated science behind it that I can't find on youtube and don't have the time to search into actual sources for a graphic to help me out.
Title: Re: Tracer smoke moves wrong way in turn fight
Post by: hitech on September 29, 2016, 10:30:13 PM
This is extremely simple to test it on the ground stationary external view pulled the trigger. Does it come from the corect spot?
Now if you rotate your guns up15 degrees and start rolling ahead,would you see the smoke trail above you? Hitech
Title: Re: Tracer smoke moves wrong way in turn fight
Post by: FLS on September 29, 2016, 10:31:58 PM
Try watching the last film before you repeat yourself....
Your film shows the smoke trail start at the gun barrel then you fly through it. Just like HiTech explained. :aok
Title: Re: Tracer smoke moves wrong way in turn fight
Post by: Chalenge on September 29, 2016, 10:39:18 PM
There is gun camera footage with this type of thing in plain view. I tried searching for it, but without success.
Title: Re: Tracer smoke moves wrong way in turn fight
Post by: Dobs on September 29, 2016, 10:47:40 PM
Why then don't you see this in other planes? And why when I do the Vaunted FLS test of filming me flying in a circle shooting, does it appear the tracers are coming out from the top of the aircraft.
I'm not saying the Tracers are wrong...I'm saying the graphic for the smoke trail is...
Title: Re: Tracer smoke moves wrong way in turn fight
Post by: Dobs on September 29, 2016, 10:49:44 PM
So maybe the length of persistence on the smoke needs to be changed so you don't feel like an X wing fighter or someone is behind you shooting......
Title: Re: Tracer smoke moves wrong way in turn fight
Post by: FLS on September 29, 2016, 10:54:49 PM
Why then don't you see this in other planes? And why when I do the Vaunted FLS test of filming me flying in a circle shooting, does it appear the tracers are coming out from the top of the aircraft.
I'm not saying the Tracers are wrong...I'm saying the graphic for the smoke trail is...
If you use the F5 view, look down on the turn circle, zoom in, slow down the speed, you will see the smoke trail start at the gun barrel then you fly through it. But I repeat myself.
Title: Re: Tracer smoke moves wrong way in turn fight
Post by: nrshida on September 30, 2016, 02:16:58 AM
Because your nose is pointed above your flight trajectory when pulling G's (I.E AOA) your shooting to the inside of your circle and as the plane goes around the circle the tracer trail goes above you and then you fly back threw it.
So the wing must 'understeer' in effect (pushes down through the air while turning)? I never expected that.
Title: Re: Tracer smoke moves wrong way in turn fight
Post by: nrshida on September 30, 2016, 02:40:00 AM
Thinking about this it's right - but counterintuitive. Dobs if you imagine a 38 flying level but with an angle of attack of, say, 30 degrees, then each tracer would make a 30 degree inclined line from the nose which would then fall behind and appear above the canopy. In a turn the Alpha relative to the flightpath is the same it's just that the line is now a curve, right?
No understeer needed :rofl
Title: Re: Tracer smoke moves wrong way in turn fight
Post by: Drane on September 30, 2016, 07:59:16 AM
This belongs in the "Help and Training" forum.
Title: Re: Tracer smoke moves wrong way in turn fight
Post by: Dobs on September 30, 2016, 09:57:35 AM
Sorry...but disagree that your AOA is fully different from your flight path (velocity vector)..it is different from the relative wind. You have to have AOA to turn...the higher your speed the lower your AOA required for the same G.
If anyone finds actual gun footage where tracers trails are going up in the fov while they are pulling Gs please share.
I understand what HT is saying, it is almost like the guns have upcant built in...
I think maybe its the persistence of the trails that is throwing me off...that I see the smoke trail above and behind me...
Title: Re: Tracer smoke moves wrong way in turn fight
Post by: hitech on September 30, 2016, 11:43:09 AM
Sorry...but disagree that your AOA is fully different from your flight path (velocity vector)..it is different from the relative wind. You have to have AOA to turn...the higher your speed the lower your AOA required for the same G.
If anyone finds actual gun footage where tracers trails are going up in the fov while they are pulling Gs please share.
I understand what HT is saying, it is almost like the guns have upcant built in...
I think maybe its the persistence of the trails that is throwing me off...that I see the smoke trail above and behind me...
Ive seen multiple gun cam showing trails going over head.
Also when I first wrote this about 15 years ago, I also thought it was a bug until it dawned on me what was going on.
HiTech
Title: Re: Tracer smoke moves wrong way in turn fight
Post by: LCADolby on September 30, 2016, 12:40:55 PM
Dobs could be right that the game is showing the tracers trails in the wrong place; logic dictates that when in a turn the trail should not be in the top of the screen but towards the bottom, because your have moved forward, up and angled up from the initial firing position where the trail began.
Title: Re: Tracer smoke moves wrong way in turn fight
Post by: FLS on September 30, 2016, 01:01:18 PM
Dobs could be right that the game is showing the tracers trails in the wrong place; logic dictates that when in a turn the trail should not be in the top of the screen but towards the bottom, because your have moved forward, up and angled up from the initial firing position where the trail began.
That is completely wrong and shown to be false on Dobs AH film.
As Hitech pointed out, firing your guns on the runway shows you where the tracer smoke originates.
The test I suggested to Dobs shows you that it still originates at the gun barrel in a turn.
Title: Re: Tracer smoke moves wrong way in turn fight
Post by: hitech on September 30, 2016, 01:31:48 PM
Dobs could be right that the game is showing the tracers trails in the wrong place; logic dictates that when in a turn the trail should not be in the top of the screen but towards the bottom, because your have moved forward, up and angled up from the initial firing position where the trail began.
Incorrect you have moved forward and down from the trail. Diagram.
At any point in Hitech's diagram he's pointing out too. You may believe you're being analytical but in fact you don't know what you're talking about. You know some terminology that you use incorrectly. You imagine one aspect of a complicated interaction and miss the relevant details. Everything is clearly explained to you and you still don't understand it. You argue without knowledge or logic or common sense.
Title: Re: Tracer smoke moves wrong way in turn fight
Post by: Dobs on September 30, 2016, 03:02:00 PM
Really...
Point out to me where I'm wrong.
I expect to see your post edited as well.
Title: Re: Tracer smoke moves wrong way in turn fight
Post by: Dobs on September 30, 2016, 03:03:27 PM
Hi tech...did you delete my post because I called him out... or did you delete my post because it was contrary to his beliefs..?
Background check for me FLS...what are your credentials in the aero world...
Because my post is now where near as bad as his...even if he is a fanboi...
Title: Re: Tracer smoke moves wrong way in turn fight
Post by: Dobs on September 30, 2016, 03:15:07 PM
So far all I've seen from FLS is a refusal to admit he could be in error.
Closed to input, argues everything, and won't explain himself. Hides behind the board, and refused to explain anything other than to say "you are wrong".
Even Hitech attempts to explain...
So you are offically a closed book for me FLS..whatever knowledge you may have, think you have, you can keep to yourself. I'm not interested in your inputs...Reminds me of GS worker.
Title: Re: Tracer smoke moves wrong way in turn fight
Post by: hitech on September 30, 2016, 03:22:20 PM
Dobs, you really fail to understand definitions of AOA.
It is the angle between the wing cord and the velocity (relative wind) vector.
By definition the velocity vector is the tangent of the circle when turning. (http://www.calla.com/fly/misc/aoa.jpg)
HiTech
Title: Re: Tracer smoke moves wrong way in turn fight
Post by: Dobs on September 30, 2016, 03:29:51 PM
I understand that, Hitech I really do...but a 4g turn at 350 knots has how much AOA vs a 4g tun at 250 knots.
Maybe what I'm missing here is what you are using as AOA units of measure....and its more than I'm expecting.
Anyway... thank you again for all the replies.
Title: Re: Tracer smoke moves wrong way in turn fight
Post by: hitech on September 30, 2016, 03:41:39 PM
I understand that, Hitech I really do...but a 4g turn at 350 knots has how much AOA vs a 4g tun at 250 knots.
Maybe what I'm missing here is what you are using as AOA units of measure....and its more than I'm expecting.
Anyway... thank you again for all the replies.
Dobs you may wish to stop while your ahead, "AOA units of measure....and its more than I'm expecting" is pretty much nonsensical.
HiTech
Title: Re: Tracer smoke moves wrong way in turn fight
Post by: Dawger on September 30, 2016, 04:03:53 PM
Assuming AOA measured in degrees, most wings reach critical AOA between 15 and 20 degrees.
So any angular difference between velocity vector and boresight is going to be less than this amount ALWAYS in WWII aircraft. Most of the time the difference is much smaller.
It is fairly easily calculated.
So any apparent angle greater than 10 degrees should be questioned for cause (canted guns as Dobs mentioned being one such cause).
Yall are all saying the same thing in this thread and because no one is using numbers, it is degenerating into a pissing contest which HTC invariably will win.
The only question that need be answered is "Does the angular difference between boresight and velocity vector meet the basic math for the shot in question?"
To answer that question you need Max AOA in degrees or radians and current AOA in the same unit (HT can just look at the AOA directly) and compare that to the angle at which the tracer smoke is diverging from the aircraft.
Anything over 20 degrees is immediately known to be bogus unless guns are canted. Anything over 10 should mean the target is below the nose in most aircraft in AH.
Title: Re: Tracer smoke moves wrong way in turn fight
Post by: hitech on September 30, 2016, 04:14:20 PM
Assuming AOA measured in degrees, most wings reach critical AOA between 15 and 20 degrees.
So any angular difference between velocity vector and boresight is going to be less than this amount ALWAYS in WWII aircraft. Most of the time the difference is much smaller.
It is fairly easily calculated.
So any apparent angle greater than 10 degrees should be questioned for cause (canted guns as Dobs mentioned being one such cause).
Yall are all saying the same thing in this thread and because no one is using numbers, it is degenerating into a pissing contest which HTC invariably will win.
The only question that need be answered is "Does the angular difference between boresight and velocity vector meet the basic math for the shot in question?"
To answer that question you need Max AOA in degrees or radians and current AOA in the same unit (HT can just look at the AOA directly) and compare that to the angle at which the tracer smoke is diverging from the aircraft.
Anything over 20 degrees is immediately known to be bogus unless guns are canted. Anything over 10 should mean the target is below the nose in most aircraft in AH.
Or you could simply look from an outside view in the film viewer turn on flight paths and let the computer do all the calculations. And see the smoke trails go up.
Or you could simply watch the smoke trails go up inside the cockpit.
Or with out any math you could understand that any positive angle the bullet trails will rise,math would simply a say of how much.
HiTech
Title: Re: Tracer smoke moves wrong way in turn fight
Post by: LCADolby on September 30, 2016, 04:21:07 PM
Ah ha now I get it, we are, to use a auto term "drifting"
The better term is flying. Drifting implies skidding which also happens in aircraft but that's not happening here. Cars don't really help you understand airplanes.
Title: Re: Tracer smoke moves wrong way in turn fight
Post by: Kingpin on September 30, 2016, 05:05:30 PM
Anything over 20 degrees is immediately known to be bogus unless guns are canted.
The guns are canted upward.
The amount that the guns must be angled upward depends on:
1) How far they are mounted below the line of sight of the pilot. The rounds must rise from the gun-barrel to the pipper (line of sight). Aircraft like the F4U, because of it's gull wing, have a significant "rise" or upward cant to the gun.
2) Your convergence setting. The ballistic properties of the gun come into play, as they are set to reach the pipper at a given range. At convergences of 200-300 yards (for example) you will notice that 50 cal rounds will continue to rise past/above the pipper as they haven't reached the apex of their ballistic arc yet. Cannons may have an even more significant upward canting to "lob" out to longer ranges.
If you use the YouTube settings to slow Dobs film down to 25% speed and look at the nose of the aircraft, you can clearly see the smoke trails originate well below the pipper (at the gun barrels at either side of the nose), rise to the where the pipper was aimed and continue onward.
The fact that he is zoomed in exaggerates the optical illusion even further. This is all in addition to the AoA vs. thrust vector issue.
Hope this information helps.
Remember this is a fun game. Play nice everyone. :)
<S> Kingpin
Title: Re: Tracer smoke moves wrong way in turn fight
Post by: Dobs on September 30, 2016, 07:28:28 PM
Actually no its not Hitech...How many alpha is 10-20-30? Is that AOA or is that a unit of measurement used by military to determine regimes of flight...exceed 30 units you are stalling the wing. 30 units =how many degrees of true AOA? That is the question I'm asking. >35 Alpha you are reliant on flight computers and thrust to keep you in the air...since you are no longer flying, but falling with style.
Does your Flight model have 20 units of AOA as stall 10 units, 15 units? I don't know...not measured anywhere. If you have stall set at large AOA, then what you put as as a diagram makes sense.
Still looking for WWII gun camera footage with tracers smoke going up while pulling Gs...let me know if you find some.
Title: Re: Tracer smoke moves wrong way in turn fight
Post by: nrshida on October 01, 2016, 12:14:07 AM
You'll kick yourself when you get this Dobs.
All the tracers are basically showing is that your nose is pitched UP relative to your actual flightpath. These kinds of aircraft don't turn at all without alpha. Whatever the curve you're flying there is always going to be a positive angle between that and your boresight - otherwise, no turn. Think about the buffeting and stall horn, that's indicating the incoming airflow is beginning to separate from the wing as you approach the upper limit to this angle of attack. That proves there must be an angle between the two vectors.
For an extreme example, imagine an aircraft firing continuously through this manoeuvre:-
The better term is flying. Drifting implies skidding which also happens in aircraft but that's not happening here. Cars don't really help you understand airplanes.
Actually they do help, because it is drifting. If it wasn't the flight path vector would always be the angle of attack.
Title: Re: Tracer smoke moves wrong way in turn fight
Post by: FLS on October 01, 2016, 01:30:34 PM
Actually they do help, because it is drifting. If it wasn't the flight path vector would always be the angle of attack.
The flight path and AOA only coincide at 0 g, aka the zero lift AOA, which is not happening in a turn. It really is called "flying".
The closest thing to drifting in a car, other than slips or skids, would be flying with a reduction of lift at high AOA as in landing.
When you think about flying keep in mind that lift is more low pressure above the wing than high pressure under the wing.
Title: Re: Tracer smoke moves wrong way in turn fight
Post by: hitech on October 01, 2016, 02:10:10 PM
In many ways wheels are similar to airfoils .
When you turn your front wheels they generate an AOA with the road/velocity vector. This AOA generates a side force and pushes the front of the car into the turn, to much AOA and the tire will / stall (under steer) I.E. start to skid and more AOA creates less slide force. The front of the car moving into the turn will start to generate an AOA on the rear tires and they also start pushing into the turn.
HiTech
Title: Re: Tracer smoke moves wrong way in turn fight
Post by: FLS on October 01, 2016, 02:22:18 PM
When you turn your front wheels they generate an AOA with the road/velocity vector. This AOA generates a side force and pushes the front of the car into the turn, to much AOA and the tire will / stall (under steer) I.E. start to skid and more AOA creates less slide force. The front of the car moving into the turn will start to generate an AOA on the rear tires and they also start pushing into the turn.
HiTech
Tire slip angle is like critical AOA. :old:
Bicycles give a good lesson in energy management. :D
I believe Dolby was looking at your diagram and thinking you were sinking into the flight path.
Title: Re: Tracer smoke moves wrong way in turn fight
Post by: LCADolby on October 01, 2016, 03:40:52 PM
See Rule #4
Title: Re: Tracer smoke moves wrong way in turn fight
Post by: FLS on October 01, 2016, 03:44:11 PM
Yes.....alot about people, their opinions of themselves, and how the game is modeled.
Did you by chance look at my post with the pictures showing 1G level flight at 221mph and 250mph?
I wasn't implying it was you that was wriggling my friend. I did look at your pictures. Can you get the same angle flying through the bottom of a loop at corner speed?
Title: Re: Tracer smoke moves wrong way in turn fight
Post by: hitech on October 03, 2016, 01:55:38 PM
Yes.....alot about people, their opinions of themselves, and how the game is modeled.
Did you by chance look at my post with the pictures showing 1G level flight at 221mph and 250mph?
I looked at them whats your point, btw you can get a good estimate of your aoa using the pitch ladder and the gun sight. There is about 1/2 to 1 deg difference between 221 and 250.
HiTech
Title: Re: Tracer smoke moves wrong way in turn fight
Post by: FLS on October 03, 2016, 02:22:17 PM
Nice tip. :aok
I assume that would be in level flight.
Title: Re: Tracer smoke moves wrong way in turn fight
Post by: Kingpin on October 03, 2016, 04:00:05 PM
you can get a good estimate of your aoa using the pitch ladder and the gun sight. There is about 1/2 to 1 deg difference between 221 and 250.
HiTech
I have also used the .target command to note the difference speed has on AoA. I actually did this a while ago when creating a gunsight for the K-4 that had hash marks set for 800 yards at speeds of 275, 300 and 325. If you are chasing someone who is extending level, the faster you are the more you need to raise the nose to "loft" a tater out at them. There is still a ton of dispersion at that distance, but every once in a while the gunsight worked and I could nail somebody running away, much to my satisfaction (and the aimbot claims that come with it).
I also noted when working on my gunnery course and using the .target command, that the Corsair in auto-level at 250mph will start with the pipper well above the bullseye and that it drops in line with the bullseye when you reach 300mph level.
So, I think with some simple trigonometry and the .target command you can figure out the angle at various speeds in level flight. The velocity vector and the target form a right triangle. The vertical distance between the pipper and the bullseye would be the length of the side opposite the angle. The distance to the target is the length of the side adjacent to the angle.
The trig formula for calculating that angle (alpha) is: tan (alpha) = Opposite / Adjacent
which converts to: alpha = arctan (O/A).
So, if the pipper is 15-feet above the bullseye at 300 yards (or 900 feet) then the calculation is: alpha = arctan (15/900) which gives an alpha of .995 degrees.
Check my math, but I think this is right.
Title: Re: Tracer smoke moves wrong way in turn fight
Post by: Kingpin on October 04, 2016, 04:47:28 AM
Dup post deleted
Title: Re: Tracer smoke moves wrong way in turn fight
Post by: Dobs on October 04, 2016, 07:02:31 AM
Based on HT's estimate of 1 to 1.5 degrees for level flight difference between 220 and 250...and what the pictures show...it appears his math is correct.