Can't find out how to use bombs

[jaylw314]

8 hours ago, Razor18 said:

I hope it will not seem as nitpicking, but we are mixing up some nomenclatures big time here.

"Setting SPI" does not designate a target, it's designating a sensor.  When you do, that sensor's target location is the SPI, wherever it happens to be pointing.

"Setting SPI" definitely designates a target (Sensor Point of Interest). You probably meant rather setting SOI (Sensor of Interest), if "it is designating a sensor" as you wrote it.

"SOI" is kind of a "which pen I will want to use to draw a point on the ground", and SPI is the point you in fact put down on the ground. You can change your pen (SOI) whenever you want to, but as long as you do not draw a new point (SPI) with your new pen (SOI) on the ground, the "previous" point is still the SPI.

 

The ONLY place that confirms what sensor is set as SPI is the data block in the lower left of the HUD.

Again, a sensor can be only set as being SOI (pen). Then you make a SPI (point) with the SOI (pen).

 

When you press China Forward Long, TGP, TAD and MAV are slaved to the location of the SPI sensor

"...are slaved to the SPI, set by the (then) SOI. "

 

When you're in CCRP mode, the guidance cues are for the location of the SPI sensor

Again, the "SPI sensor" is the SOI. "Location of the SPI sensor" is the SPI.

 

When you set SPI as STPT, you're using the EGI as a "sensor', and it can provide the same above functions.

You can set STPT as SPI, or set SPI to STPT.

 

"...You might be able to use it as a weird "CCIP" mode for JDAMs by using the gun pipper as the designator setting their target.  I haven't tried this and that's a pretty strange use case..."

What's the advantage of using the gun pipper as SOI, instead of the much smaller DTS slaved to the flight path marker (or velocity vector) to set SPI for a JDAM? Actually both is impossible unless you want to fly close enough to visually locate your target, sacrificing JDAM standoff (altitude and or distance) in the designating process.  I think using the IFFCC as a SOI is much better to use for a gun run, to fine tune your gun aim, looking at the TGP.

Again, didn't meant to nitpick.

 

 

It's not nitpicking, just semantics.  I did clarify that the sensor's target location is the SPI, but you seemed to miss that or deemphasize that. 

I try to explain it this way so that people realize when they move the designated sensor around, the SPI moves around.

[Frederf]

Correct language helps understanding. TMS forward long "designates the currently selected sensor as the SPI generator". The P in SPI means point. Points can only come from sensors. What TMS forward long does is pick which sensor is "of interest" (the i in SPI). Every sensor has a point that could be "of interest" all at the same time. What the pilot is picking which sensor out of all the choices gets to make that sensor's point the SPI. The SPI always exists somewhere (rare exception) like a physical copper-and-zinc penny. The penny isn't brought into existence, duplicated, or destroyed. There's one penny and it gets moved around based on the desires of different masters.

Some language is formed in a way that seems like they are saying "I create the penny here." But you're not creating the penny. You're saying the penny is to be placed by X sensor. And it is the sensor which tells the penny to move out according to that sensor's info. It's indirect. The pilot picks the sensor and the sensor (not the pilot) directs the SPI.

That's why we say "TGP as SPI". The sensor as (or is) the source of the point. But the TGP isn't SPI, it can't be. TGP is a sensor and SPI is a point. How can a sensor be a point?

---

SOI is sensor of interest which can be simply stated as "selected." SOI and SPI have almost nothing to do with each other. SOI is just which sensor the controls (cursor, TMS, etc.) are controlling. There isn't enough room in the airplane to make a duplicate set of controls for every sensor. Instead there is one set of controls and it's shared by all the sensors. Which one sensor the controls act on is chosen by SOI selection.

The processing of picking which sensor is the SPI generator happens to be that that sensor is selected and then a universal designate-this-sensor-as-SPI-generator. But apart from that SOI and SPI are separate concepts. You can make sensor X the SPI source and sensor Y is SOI and they are separate concepts, ya know except that the designation process designates based on SOI but after that SOI can be anything.

---

Now people abbreviate the concept all the time but new pilots may get misled by those abbreviations above. As evidenced above, "Oh it's not just setting a point, it's setting the sensor which forever determines the point."

[Yurgon]

12 hours ago, Razor18 said:

"Setting SPI" definitely designates a target (Sensor Point of Interest). You probably meant rather setting SOI (Sensor of Interest), if "it is designating a sensor" as you wrote it.

"SOI" is kind of a "which pen I will want to use to draw a point on the ground", and SPI is the point you in fact put down on the ground. You can change your pen (SOI) whenever you want to, but as long as you do not draw a new point (SPI) with your new pen (SOI) on the ground, the "previous" point is still the SPI.

Let's just quickly clarify this with a practical example.

Say I set my TGP as SOI, point it at a target, maybe a T-72 MBT, and hit TMS Forward Long.

Now I slew the TGP onto a nearby house.

What's my aircraft's SPI? The tank or the house?

Edited January 28, 2022 by Yurgon

[Razor18]

Tank, until you press TMS FWD long again.

[Yurgon]

9 minutes ago, Razor18 said:

Tank, until you press TMS FWD long again.

So, Slave all to SPI should slew the TGP back to the tank again, correct?

And a CCRP attack, let's assume we're dropping a JDAM, should also hit the tank, even when the TGP points at the house at time of bomb release, correct?

Could you do me a favor and quickly test this in DCS?

Edited January 28, 2022 by Yurgon
Clarification

[Razor18]

I see what you mean. But then what is the function of TMS FWD Long?

[Yurgon]

1 minute ago, Razor18 said:

I see what you mean. But then what is the function of TMS FWD Long?

That's what jaylw314 described in the post you criticized.

[Razor18]

Then what is the function of coolie hat right long for instance, if there is a (let's say TGP) sensor up on the right DDI?

[Yurgon]

1 hour ago, Razor18 said:

Then what is the function of coolie hat right long for instance, if there is a (let's say TGP) sensor up on the right DDI?

I think you understand what SOI is, and Frederf also made an excellent point describing that above.

Coolie Hat Right Long just makes the sensor on the right MFCD the SOI, nothing fancy about it.

The really important part, and the one that's not very obvious, is that TMS Forward Long does not designate a point to be the SPI, until another SPI is set with TMS Forward Long again. What it does is it designates a sensor, which from that point onward will keep generating the SPI.

The TGP as SPI generator will slew the SPI with it.

The TAD as SPI generator will make whatever is hooked the SPI, and when another TAD object is hooked, the SPI will change to that new object (well, its coordinates, obviously).

STPT as SPI generator will make whatever is selected as steerpoint the SPI.

HUD as SPI generator will make the TDC's location the SPI, and will slew the SPI with the TDC.

HMCS as SPI will make whatever is hooked in the helmet the SPI, or with nothing hooked, the HDC will be the SPI, and the SPI will be slewed with the HDC then.

That's why it's so important to check the lower left corner of the HUD before every CCRP release: because aside from the wedding cake in the TGP and the SPI symbol with the green line in the helmet, it's the only reference available to the pilot on what sensor is actually generating the SPI at that particular moment.

Also really important to know: when a sensor can no longer generate a valid SPI (line of sight near or above the horizon, for example), the SPI generator automatically reverts to STPT, and there are no cues letting the pilot know about it, other than the wedding cake in the TAD and the HMCS SPI indicator updating to the new SPI, and of course the HUD showing STPT instead of whatever generated the SPI before.

Does that make sense?

Edited January 28, 2022 by Yurgon
Clarification

[Razor18]

9 minutes ago, Yurgon said:

Coolie Hat Right Long just makes the sensor on the right MFCD the SOI, nothing fancy about it.

If you then move the SOI (TGP) around and for instance Area Track it onto a building with TMS UP Short, but you do NOT press TMS UP Long, will you be able to drop ordnance on that building?

Edited January 28, 2022 by Razor18

[Yurgon]

15 minutes ago, Razor18 said:

If you then move the SOI (TGP) around and for instance Area Track it onto a building with TMS UP Short, but you do NOT press TMS UP Long, will you be able to drop ordnance on that building?

Yeah, absolutely, provided that the TGP was already set as SPI generator before.

Quick example:

I've got the TGP on a tank, but my SPI generator is still STPT. I make the TGP SOI, and then TMS Forward Long to also make it SPI generator. With the TGP firmly on the tank, I could now use weapons against it.

Next, I decide to slew the TAD, so SOI the TAD, slew it around, maybe hook an object or whatever. I'm not touching the SPI Generator, that is still my TGP.

Now I'm done looking at the TAD, I come back to the TGP as SOI with Coolie Hat Right Long, and decide that the tank can live for a few more minutes, instead I want the building next to it gone. I slew the TGP over to the building, double check the HUD and make sure the TGP is still generating my SPI, and if I now drop a JDAM, it'll go to that building (minus the JDAM's guidance error).

*****

Let's expand on that. I decide that the tank has to go next. With the TGP still SPI generator, I slew it back to the tank and set myself up for another JDAM attack.

While running in, I want to look something up on the TAD, so I SOI the TAD again, slew it around, hook my wingman, check my distance to the tank. With the TAD still SOI, I double check  the HUD to make sure that the TGP is still SPI generator. Once in range, I pickle the JDAM, and it goes to the tank (again, minus any JDAM guidance error).

[Frederf]

2 hours ago, Razor18 said:

Tank, until you press TMS FWD long again.

Nope. When TGP is the SPI source the SPI follows the TGP wherever it goes. SPI is updated many, many times per second. Where the TGP happened to be pointed at the moment the sensor was elevated isn't special or recorded. You slave all to SPI, every other sensor is going to slave to where the TGP is right now. The TGP isn't going to do anything because it's not going to slave to itself.

Now sometimes a sensor will go invalid and the SPI source will change automatically back to STPT. Certain sensors can't remain SPI source if their point is invalid.

[jaylw314]

1 hour ago, Razor18 said:

If you then move the SOI (TGP) around and for instance Area Track it onto a building with TMS UP Short, but you do NOT press TMS UP Long, will you be able to drop ordnance on that building?

If you use a TGP-guided weapon using CCIP, like TGP-->CCIP-->GBU-12 or TGP-->CCIP-->APKWS, absolutely!  Like I said, the SPI is irrelevant for that kind of weapons employment.  If your SPI was STPT to a waypoint 200 miles away, those workflows would still hit the building.

If, on the other hand

• You need to slave something to the TGP, like TGP-->CCIP-->MAV (EO or IR), you better make sure the TGP is SPI before you press China Hat forward long.  If not, your MAV seeker will point the steerpoint 200 miles away
• You need to use CCRP, you better make sure TGP is SPI, otherwise the CCRP cues will direct you to the steerpoint 200 miles away.  If the steerpoint was pretty close to the building, this might still work!
• You need to use a GPS/INS weapon, your JDAM will try to target the steerpoint 200 miles away unless you make the TGP SPI.

Edited January 28, 2022 by jaylw314

[Razor18]

Oh, I think I get it now. Making something SOI only tells the system "I want to manipulate this sensor around". With TMS FWD long I give a "target pointer" into the handof the SOI, but don't "draw" any point on the ground, rather wherever the pointer points to at any time, will be the point to attack.

Thanks for enlighten me !

[QuiGon]

3 hours ago, Razor18 said:

Oh, I think I get it now. Making something SOI only tells the system "I want to manipulate this sensor around". With TMS FWD long I give a "target pointer" into the handof the SOI, but don't "draw" any point on the ground, rather wherever the pointer points to at any time, will be the point to attack.

Thanks for enlighten me !

Reading quickly through this thread, I wonder if you come from the F-16 or F/A-18?
Because in the A-10C the SOI and SPI are independend of each other. You can have your TGP generating a SPI on the ground, while you have another sensor as your SOI. This is not possible in the F-16, where the SPI is always tied to the SOI.
And unlike in the F/A-18, the SPI (WPDSG) position gets constantly updated by the sensor that is declared as the SPI generator (shown in the bottom left corner of the HUD), while in the F/A-18 you have to manually redesignate a new position as the SPI (WPDSG).

The sensor magament in A-10C is very powerful and you can get sensors and weapons pointed to where you want them much quicker than with the Viper or the Hornet, once you got your head around how the A-10C sensor logic works.

Edited January 29, 2022 by QuiGon

[Razor18]

No, A-10C since very early. Apparently did it wrong until now.

[QuiGon]

3 minutes ago, Razor18 said:

No, A-10C since very early. Apparently did it wrong until now.

Oh, wow, then this should make you an even better Hawg Driver now

Edited January 29, 2022 by QuiGon

[DN308]

Many thanks again for all your advices.

If you don’t mind, could you explain how to mark a ToO with the HMCS?

Each time I try to use the HMCS’s reticle, the mark I receive is way too low compare to the point I want to designate.

[jaylw314]

15 hours ago, Razor18 said:

Oh, I think I get it now. Making something SOI only tells the system "I want to manipulate this sensor around". With TMS FWD long I give a "target pointer" into the handof the SOI, but don't "draw" any point on the ground, rather wherever the pointer points to at any time, will be the point to attack.

Thanks for enlighten me !

It's like a Eureka moment, isn't it?  All of a sudden, it goes from inscrutable to the coolest thing in the world!  

11 hours ago, DN308 said:

Many thanks again for all your advices.

If you don’t mind, could you explain how to mark a ToO with the HMCS?

Each time I try to use the HMCS’s reticle, the mark I receive is way too low compare to the point I want to designate.

Hard to know, but realize when you make a mark point using TMS Right short with HMCS as SOI, it marks the location of the HDC, not the center cross.  By default, the HDC is slaved to the center cross, it'll look like an "iron cross" when so.  But if you've slewed the HDC somewhere, the markpoint will created there, which might not be where you're looking

[DN308]

All right, thanks

[Yurgon]

On 1/29/2022 at 11:16 AM, Razor18 said:

With TMS FWD long I give a "target pointer" into the handof the SOI, but don't "draw" any point on the ground, rather wherever the pointer points to at any time, will be the point to attack.

Exactly!

Just one more example: Let's say TGP is SOI, and TGP is SPI Generator. Slew TGP onto a vehicle, let's say a T-72 MBT, in POINT track. The tank moves along a road.

Now we can set TAD as SOI and slew around the TAD, or hook TAD objects or whatever. Meanwhile, the SPI actually keeps moving with the T-72 for as long as the TGP keeps tracking the tank. We could now follow that tank for an hour, while it travels 10+ miles, and if we manage to not mask the TGP, we can then drop a GBU-12 in CCRP and, with proper terminal guidance, it should kill the tank, regardless of our SOI at that time.

Edited January 30, 2022 by Yurgon

[QuiGon]

16 hours ago, Yurgon said:

Exactly!

Just one more example: Let's say TGP is SOI, and TGP is SPI Generator. Slew TGP onto a vehicle, let's say a T-72 MBT, in POINT track. The tank moves along a road.

Now we can set TAD as SOI and slew around the TAD, or hook TAD objects or whatever. Meanwhile, the SPI actually keeps moving with the T-72 for as long as the TGP keeps tracking the tank. We could now follow that tank for an hour, while it travels 10+ miles

And then you can also broadcast your SPI to your flight, so a wingman can make your SPI his SPI and slave his TGP to the SPI, so his TGP would follow the tank that you're tracking with your TGP.

That's why I love the A-10C and it's sensor management so much, because it's very complex, but follows a certain logic that makes it easy to use.

Edited January 31, 2022 by QuiGon

[DN308]

Well @QuiGon, you’ve just won another dumb question...

 

How do you broadcast it?

And BTW, how do you receive some (or JTAC message that you can inject in your CDU/TAD or so on)?

And of course, how you do all that <profanity>? 

I guess I still have 5 more years of works to understand and use all of these

[QuiGon]

12 minutes ago, DN308 said:

Well @QuiGon, you’ve just won another dumb question...

I'm always glad to help
 

12 minutes ago, DN308 said:

How do you broadcast it?

TMS LEFT LONG
 

12 minutes ago, DN308 said:

And BTW, how do you receive some (or JTAC message that you can inject in your CDU/TAD or so on)?

To properly recieve a broadcasted SPI from your wingman, you just need to be in the same data link group. You can change your data link group and personal ID on the NET subpage of the TAD. And your wingman needs to transmit his SPI of course.

To recieve a JTAC message you just need to get in contact with a JTAC that has a target for you and he will send the message to you. To send such a message to a wingman, you need to have a valid SPI position, the wingman hooked on the TAD and then use the send button on the TAD.
 

12 minutes ago, DN308 said:

And of course, how you do all that <profanity>? 

I guess I still have 5 more years of works to understand and use all of these

Well, I'm flying this bird for 10 years now

[DN308]

A great thank you