New gun AG pipper behavior.

[Ramsay]

We do not (yet) have the GPS errors (horizontal and vertical) displayed on the SMS page, but I doubt these errors are modelled in detail.

Yeah, most of this doesn't seem modelled in DCS (doesn't effect my enjoyment either).

 

I'm not so much interested in GPS errors "per se", rather I'm curious about the RL effect of not setting a target elevation in Nevada i.e. 5,000 ft, etc. (I like being punished for not doing things right :lol: )

 

Note: I'm not sure if this is new but I can't set a mid air waypoint in Nevada, all the waypoints I created in the ME were at ground level (EHSD data page and as seen on the HUD).

 

The A-10C seems ok, but editing the AV-8B's waypoint elevation using the EHSD waypoint data ODU > Elev

 

Entering 500 ft = 152 ft

 

It looks like a conversion error as 500 ft = 152 m.

 

Entering 25,000 ft = 7619 ft on the EHSD waypoint data block but didnt change the height/3D position of HUD waypoint circle which stayed firmly fixed to the ground.

[shagrat]

Yeah, most of this doesn't seem modelled in DCS (doesn't effect my enjoyment either).

 

 

 

I'm not so much interested in GPS errors "per se", rather I'm curious about the RL effect of not setting a target elevation in Nevada i.e. 5,000 ft, etc. (I like being punished for not doing things right )

 

 

 

Note: I'm not sure if this is new but I can't set a mid air waypoint in Nevada, all the waypoints I created in the ME were at ground level (EHSD data page and as seen on the HUD).

 

 

 

The A-10C seems ok, but editing the AV-8B's waypoint elevation using the EHSD waypoint data ODU > Elev

 

 

 

Entering 500 ft = 152 ft

 

 

 

It looks like a conversion error as 500 ft = 152 m.

 

 

 

Entering 25,000 ft = 7619 ft on the EHSD waypoint data block but didnt change the height/3D position of HUD waypoint circle which stayed firmly fixed to the ground.

Yep, sounds like conversion. I can't say for the AV-8B, maybe WIP, but the F/A-18C let you switch between metric and feet. I am pretty sure the waypoint elevation when entered manually will mess up your waypoint like in other modules. I think even the A-10C DTS uses basically the elevation grid of the DCS World map and not a "separate" digital map, but as you said this " too much accuracy" isn't a showstopper for me, and it is totally enjoyable.

There are limits to compute and memory resources in a computer game /simulation and before we waste cpu cycles on this, we should consider the FLIR hot spot indicators, or accurate Infrared heat map etc. or the detailed fuzing options and effects... though that would be EDs part and looking at current JDAM progress is promising. :)

Overall I am very happy with the progress visible in the AV-8B and falling more and more in love with it.

[Ramsay]

I am pretty sure the waypoint elevation when entered manually will mess up your waypoint like in other modules.

This is a new bug/behaviour.

 

Previously if I set a flight plan with waypoints at 20,000 ft the guidance, while not being perfect, would be in the region of 20,000 ft (perhaps higher / perhaps lower), now the waypoints are at ground level and ignore the ME setting.

 

I'm not sure if the ODU waypoint elevation adjustment ever worked but had to check, before making a report.

[shagrat]

This is a new bug/behaviour.

 

Previously if I set a flight plan with waypoints at 20,000 ft the guidance, while not being perfect, would be in the region of 20,000 ft (perhaps higher / perhaps lower), now the waypoints are at ground level and ignore the ME setting.

 

I'm not sure if the ODU waypoint elevation adjustment ever worked but had to check, before making a report.

Sounds like a bug. 20k ft should be above ground level almost everywhere except the Himalaya. ;)

[Harlikwin]

Yeah, most of this doesn't seem modelled in DCS (doesn't effect my enjoyment either).

 

I'm not so much interested in GPS errors "per se", rather I'm curious about the RL effect of not setting a target elevation in Nevada i.e. 5,000 ft, etc. (I like being punished for not doing things right :lol: )

 

Thats my main gripe. And where in fact discovered the discrepancy. If you have no WP loaded on that map, it defaults the altitude to sea level 0m. But CCIP still works perfectly despite the fact the target alt is 5000ft or whatever. Same problem when bombing in the mountains.

 

While I'd also like to see some level of GPS error modled for all sorts of reasons (I'd rather see GPS jamming or spoofing actually). I'd really be fairly content if they fixed these glaring errors and let people do it wrong, or at least worry about doing it right.

[Ramsay]

Section 1.12 .17 "GPS usage considerations"... and basically the whole chapter about map coordinate integration into the MC via the MPS/DSU. Depending on the original map accuracy, of course, which serves as the basis for coordinate calculation.

 

I don't see a section that says DTED is used directly for CCIP

 

"... target elevation is a critical component of the target coordinate; both Baro and GPS bombing will be significantly degraded if correct target elevation in not used."

 

While the GPS section describes the aircraft's positional errors and the problems of using digitised data, it also repeats that target elevation is calculated from the waypoint's elevation.

 

1.12.10.1 Using GPS Altitude.

 

When using GPS altitude in CCIP mode, the waypoint / waypoint offset elevation is subtracted from GPS altitude to derive the height above target.

 

You might want to look into Tacman 1.12.14. Mission Planning System, also.

No mention of using DTED directly, rather it describes a GPS database of 200 (perhaps older software version) navigation points in the DSU (data storage unit) that the pilot can copy/paste into a active waypoint (0-59) or markpoint (0-9).

 

There's a big difference between using the Mission Planning System back at the base to digitise Map and DTED data for the DSU's waypoints and using DTED on the 'fly'.

[shagrat]

I don't see a section that says DTED is used directly for CCIP

 

 

 

"... target elevation is a critical component of the target coordinate; both Baro and GPS bombing will be significantly degraded if correct target elevation in not used."

 

 

 

While the GPS section describes the aircraft's positional errors and the problems of using digitised data, it also repeats that target elevation is calculated from the waypoint's elevation.

 

 

 

 

 

 

 

 

 

No mention of using DTED directly, rather it describes a GPS database of 200 (perhaps older software version) navigation points in the DSU (data storage unit) that the pilot can copy/paste into a active waypoint (0-59) or markpoint (0-9).

 

 

 

There's a big difference between using the Mission Planning System back at the base to digitise Map and DTED data for the DSU's waypoints and using DTED on the 'fly'.

Isn't the digital map providing at least the isolines to the MC?

That is what DefenseMappingAgency (now NGIA) does, if I am not mistaken. I am aware it is nowhere near accurate enough to provide a point solution, but to adjust to about 100ft to 200ft per isoline, depending on scale should be good enough for a rough target elevation.

Gun pipper, when in range, switches to RCIP to get the final solution.

If you are on a reasonable close plain as the target it should be a good point solution?

Another thought about the Gun pipper: as the impact point of the bullets (first convergence of LOS with bullet trajectory) is at a fixed point, the MC could calculate the range indication (range tape) with just the RCIP as we talk about a 1NM(6000ft) slant range, typically.

When I fire at ranges greater then 1,2 NM the bullets hit long and that would be accurate if the pippers impact point represents the fixed convergence of LOS and bullet tracjectory like a classic collimated sight? That would explain, why the pipper isn't "jumping". The MC only calculates "in range" and projects a wind compensated pipper?

I couldn't find anything detailing this in the documents, so it is just an assumption based on observation and what I know about sights. :dunno:

[Harlikwin]

I don't see a section that says DTED is used directly for CCIP

"... target elevation is a critical component of the target coordinate; both Baro and GPS bombing will be significantly degraded if correct target elevation in not used."

 

While the GPS section describes the aircraft's positional errors and the problems of using digitised data, it also repeats that target elevation is calculated from the waypoint's elevation.

 

 

 

 

No mention of using DTED directly, rather it describes a GPS database of 200 (perhaps older software version) navigation points in the DSU (data storage unit) that the pilot can copy/paste into a active waypoint (0-59) or markpoint (0-9).

 

There's a big difference between using the Mission Planning System back at the base to digitise Map and DTED data for the DSU's waypoints and using DTED on the 'fly'.

 

This has what I've been saying all along.

 

And really with RCIP and flat ground its largely a non issue. But for those cases where where there things like hills (like, the caucuses, nevada, and PG), its a relevant problem for attack pilots.

 

To do it "right" I basically ARBS the target anyway since that will give me the best ranging solution.

[Harlikwin]

Isn't the digital map providing at least the isolines to the MC?

That is what DefenseMappingAgency (now NGIA) does, if I am not mistaken. I am aware it is nowhere near accurate enough to provide a point solution, but to adjust to about 100ft to 200ft per isoline, depending on scale should be good enough for a rough target elevation.

Gun pipper, when in range, switches to RCIP to get the final solution.

If you are on a reasonable close plain as the target it should be a good point solution?

Another thought about the Gun pipper: as the impact point of the bullets (first convergence of LOS with bullet trajectory) is at a fixed point, the MC could calculate the range indication (range tape) with just the RCIP as we talk about a 1NM(6000ft) slant range, typically.

When I fire at ranges greater then 1,2 NM the bullets hit long and that would be accurate if the pippers impact point represents the fixed convergence of LOS and bullet tracjectory like a classic collimated sight? That would explain, why the pipper isn't "jumping". The MC only calculates "in range" and projects a wind compensated pipper?

I couldn't find anything detailing this in the documents, so it is just an assumption based on observation and what I know about sights. :dunno:

 

Part of the issue is the actual DTED level used, DTED 0/1 are pretty innacurate for this purpose (fine for general nav though).

[Fri13]

It was more of a rhetorical question. And yes, either ARBS, or radar/baro/gps alt is how i know it to work. And no errors of target alt modled as far as i know. Either with this method or the ARBS. (I think someone tested the Arbs more recently and it might model error now, but i cant recall)

 

I tested it, and if the target was at another altitude than you are and you didn't have ARBS locked, then you did miss the target with bombs (CCIP/AUTO). But then we got that CCIP update to have cross locked bottom of the HUD. And now with cannon I can hit at anything that is just behind the pipper, regardless is there a 1500 meter altitude difference between terrain under me and the target. The pipper doesn't seem to move, but the scale doesn't change until I am closer to same altitude (slope).

[shagrat]

I tested it, and if the target was at another altitude than you are and you didn't have ARBS locked, then you did miss the target with bombs (CCIP/AUTO). But then we got that CCIP update to have cross locked bottom of the HUD. And now with cannon I can hit at anything that is just behind the pipper, regardless is there a 1500 meter altitude difference between terrain under me and the target. The pipper doesn't seem to move, but the scale doesn't change until I am closer to same altitude (slope).

Guns CCIP without designation seems to project a pipper along the LOS at the sweet spot, where bullet trajectory intersects roughly around 3300 ft. Now, that is a fixed point in space and the only thing the MC needs to calculate, is when the point intersects with the ground. That is what the range tape provides, starting at a slant range of 6000 ft. When I fire at more than 6000ft slant range the shot goes long(!) as in "bullets raising above LOS and go over the target". Only around the 5000ft to 2000ft it is pretty accurate.

This makes me believe the MC is calculating the (slant) range tape only, using RCIP and triangulation. It may be a lucky coincidence that your elevated targets are still in the trajectory at greater distances, as the bullets rise above the LOS and fall again later...

I have never seen the pipper adjust to different terrain height! If(!) the calculation was based on the actual ground elevation in DCS as you suspect, would not the pipper jump with each hill it passes, as it would not know when you would press the trigger? If it would "cheat" and simply follow the terrain, it must move as if glued to the terrain, or am I thinking in the wrong direction? I never noticed the pipper "jumping" with terrain elevation. :dunno:

[Holbeach]

Yep, same here. I get GCIP if I do not designate via other means, RCIP when low enough.

Only thing I find a bit weird is the Min/Max range cues seem a bit low with 2000ft/3600ft. I get the Pull Up warning way(!) before even close to the target and will definitely fly straight over it when I try to fire I inside the range cues... or am I supposed to get that close?

 

 

The gun makers demo states that slant range between 3000' and 2000' at 500 kts is required for medium tank armour penetration. 3400' being marginal.

The pull up warning is the first thing I turn off.

 

 

..

[shagrat]

The gun makers demo states that slant range between 3000' and 2000' at 500 kts is required for medium tank armour penetration. 3400' being marginal.

The pull up warning is the first thing I turn off.

 

 

..

Ok, so we have a nice challenge here. Get your shots on target inside optimum range and evade target and ricochets at a speed of 500 kts.

"Use the force Luke!"

[Holbeach]

I forgot to mention. Attack at a 5 deg dive angle, which is best for tanks.

I found it easiest, using the gun cross.

..

Edited August 20, 2019 by Holbeach

[shagrat]

I forgot to mention. Attack at a 5 deg dive angle, which is best for tanks.

I found it easiest, using the gun cross.

..

Shallow gun run for the win. So with 5-10° and approach speed around 500kts I get a left/right bank working without killing myself. Still quick wits required to coordinate this into a timespan of 1 to 1.5 sec... thanks for the hints.

[Holbeach]

I was a bit dissappointed to find I could kill T-72, T-80 and T-90 tanks with this gun. There is no way that 25mm bullets would be able to penetrate MBT armour. T-55 yes, but not these big boys.

..

[shagrat]

I was a bit dissappointed to find I could kill T-72, T-80 and T-90 tanks with this gun. There is no way that 25mm bullets would be able to penetrate MBT armour. T-55 yes, but not these big boys.

..

Yep, Sections with hitpoints. Composite armor effects are not modeled in DCS, AFAIK.

Though with 25mm or even 20mm AP through the top armor and especially engine compartment you can still disable a modern Tank, with a bit of luck... at least we were told when getting to grips the late 90ies Leopard 2A4 MBT. So my guess is T-72 and T-80 is plausible when hitting it right, but never a T-90. ;)

 

EDIT: though, we already have internal damage modeled with vehicles, instead of just an overall hitpoint bar.

Edited August 21, 2019 by shagrat

[Harlikwin]

I was a bit dissappointed to find I could kill T-72, T-80 and T-90 tanks with this gun. There is no way that 25mm bullets would be able to penetrate MBT armour. T-55 yes, but not these big boys.

..

 

Its all about aspect. It shouldn't have issues with any of them from the rear/top.

[shagrat]

I don't see a section that says DTED is used directly for CCIP

 

 

 

"... target elevation is a critical component of the target coordinate; both Baro and GPS bombing will be significantly degraded if correct target elevation in not used."

 

 

 

While the GPS section describes the aircraft's positional errors and the problems of using digitised data, it also repeats that target elevation is calculated from the waypoint's elevation.

 

 

 

 

 

 

 

 

 

No mention of using DTED directly, rather it describes a GPS database of 200 (perhaps older software version) navigation points in the DSU (data storage unit) that the pilot can copy/paste into a active waypoint (0-59) or markpoint (0-9).

 

 

 

There's a big difference between using the Mission Planning System back at the base to digitise Map and DTED data for the DSU's waypoints and using DTED on the 'fly'.

I finally found the DTED reference. It is in the real life flight manual. Section 23.9.39 and 23.9.42 with TAMMAC (TacAir Moving MAp Capability), which is obviously available.

We can even see the DTED from the map loaded into the MC in action.

Watch Red Kites tutorial at 2:25. When he slews the waypoint coordinates and ELEV updates constantly...

 

[Dudikoff]

Its all about aspect. It shouldn't have issues with any of them from the rear/top.

 

T-72 turret roof armor over the crew area should be like 45 mm, the rear has like 65 mm. Supposedly the thickness of the hull roof over the engine compartment is 40 mm, but I'm not sure if that's valid for those big covers over it as well.

 

As I couldn't find any ammo GAU-12 uses that can handle that, I wouldn't quite agree with your statement of it taking out T-72s.

Edited August 31, 2019 by Dudikoff

[Ramsay]

I finally found the DTED reference. It is in the real life flight manual. Section 23.9.39 and 23.9.42 with TAMMAC (TacAir Moving MAp Capability), which is obviously available.

 

23.9.39 describes the different "image formats" the MPCD can display Chart, DTED and CIB (Controlled Image Base) - in DCS we can only view the Chart type.

 

As a counter argument to direct DTED use :-

 

23.9.20 Markpoints describes how the altitude of the current steer point is used if the Radar altimeter isn't available.

 

Watch Red Kites tutorial at 2:25. When he slews the waypoint coordinates and ELEV updates constantly...

 

I'm aware of how it works in DCS.

[Gunnar81]

T-72 turret roof armor over the crew area should be like 45 mm, the rear has like 65 mm. Supposedly the thickness of the hull roof over the engine compartment is 40 mm, but I'm not sure if that's valid for those big covers over it as well.

 

As I couldn't find any ammo GAU-12 uses that can handle that, I wouldn't quite agree with your statement of it taking out T-72s.

 

Not to get this thread too off topic. But speaking of GAU-12 ammo. Has anyone heard if we are going to be able to change ammo mixes with this gun? For some missions it would be nice to be able to load a HEI mix or maybe straight AP. I haven't been able to find anything on the subject. Thanks...