Mi-24 Bombing - sight, timer system info on how it's done IRL?

[fargo007]

They've made the articulating front seat sight usable, and the bomb timer as well.  Has anyone dug into how these are to be employed for bomb dropping?

I'm staying away from the KMGU/USLP clusterbombs for now since they create a horrible frame rate issue.  But we do see examples of dumb bombs being used IRL. 

 

 

[AeriaGloria]

Yes there are tables for altitudes speeds and amount of depression and timer needed.

I assume this information will be in the final manual.

there are tables on the Mi-35P manual of the export version of our Mi-24P that I have, but not sure if it’s okay to post them 

[fargo007]

No need, I have those. They still don't make it clear how the equipment is to be used.

 

[AeriaGloria]

10 hours ago, fargo007 said:

No need, I have those. They still don't make it clear how the equipment is to be used.

 

So did I, I’m sure you’re referring to the appendix in section 6 that has the tables.

if you have the same PDF I have, there is a section 5 on “Specual Occurances in Flight.” In that same PDF file right after Section 5 is Sextion 6, “General Information on Sighting.” That will describe how to use the table, basically the sight has to be set to 30 degrees almost always. So if you see something for Section 5, scroll past it and 6 might be there also if we have the same PDF zip file download

Edited November 24, 2021 by AeriaGloria

[fargo007]

Thanks, I am on my way to sorting it out!   

 

Now I need to figure out why all the bombs drop when the operator does the bombing, and only one at a time drops when the pilot does it.

[Quati]

On 11/23/2021 at 11:33 AM, fargo007 said:

They've made the articulating front seat sight usable, and the bomb timer as well.  Has anyone dug into how these are to be employed for bomb dropping?

A few days ago I began revisit those bomb tables from the Mi-35P Manual that has being around and, again, was not understanding how to use it because it's not explained in the manual what the Θ (theta) symbol of 21s, 25s and 30s means.

This time I tried to do more research and found that this Θ represents the "Characteristic Time" of a bomb. That is the time it takes for a bomb dropped from 2000m altitude with a ground speed of 144km/h (40m/s) from a level flight. More info bellow.

https://ru.wikipedia.org/wiki/Характеристическое_время_(баллистика)

http://adminland.ru/crimea/books/sh_hb/part05.htm

http://samlib.ru/t/tonina_o_i/we_400.shtml

I did not yet found any table with the Characteristic Time of the bombs available for the Mi-24P (real or  DCS) so I went for to discover by myself and got this graph below.

null

Got this on Caucasus, with no wind at all, 15°C and 760mmHg at sea level, 2000m height (Helicopter at an altitude of 2008m and target at 8m), Ground speed of 159km/h, Air speed of 144km/h (40m/s) on a level flight (0° pitch).

As I had a lot of issues with the replay so I marked the time with a chronometer and used the average of 3 tests per bomb while in Active Pause.

In conclusion;

• one should use the Θ=21s on the Bombing Sight Tables from the Mi-35 Manual for all Bombs (HD M-54 and LD M-62) and Cluster Bombs
• maybe the Θ=25s could be used for the KMGU-2 Bomblets Dispenser.
• I'm still looking for the real Characteristic Time for those bombs to compare with DCS.

[IronChancellor]

On 11/23/2021 at 8:33 AM, fargo007 said:

They've made the articulating front seat sight usable, and the bomb timer as well.  Has anyone dug into how these are to be employed for bomb dropping?

How does the bomb timer work?

[Avimimus]

On 11/23/2021 at 9:33 AM, fargo007 said:

They've made the articulating front seat sight usable, and the bomb timer as well.  Has anyone dug into how these are to be employed for bomb dropping?

From the one report I've read... the crews in Afghanistan learned to do it intuitively... like a WW2 fighter-bomber pilot. Some reportedly became quite accurate after they got enough experience.

Part of me still wants the MBD racks so we can carry the 10xFAB-100 bomb load that was used occasionally in Afghanistan.

I find it particularly amusing as this was the exact bomb load of some bombers which carried earlier versions of the FAB-100 during the Great Patriotic War / WWII...!

[AeriaGloria]

1 hour ago, IronChancellor said:

How does the bomb timer work?

You set sight in CPG seat to 30 degrees. You set timers to allotted time in table. Once target passes pipper, flip “calculation” switch on timers to start then counting. Once they finish counting, a light will go off in the PKV sight frame, and the CPG then drops bombs when seeing the light 

2 hours ago, Quati said:

A few days ago I began revisit those bomb tables from the Mi-35P Manual that has being around and, again, was not understanding how to use it because it's not explained in the manual what the Θ (theta) symbol of 21s, 25s and 30s means.

This time I tried to do more research and found that this Θ represents the "Characteristic Time" of a bomb. That is the time it takes for a bomb dropped from 2000m altitude with a ground speed of 144km/h (40m/s) from a level flight. More info bellow.

https://ru.wikipedia.org/wiki/Характеристическое_время_(баллистика)

http://adminland.ru/crimea/books/sh_hb/part05.htm

http://samlib.ru/t/tonina_o_i/we_400.shtml

I did not yet found any table with the Characteristic Time of the bombs available for the Mi-24P (real or  DCS) so I went for to discover by myself and got this graph below.

null

Got this on Caucasus, with no wind at all, 15°C and 760mmHg at sea level, 2000m height (Helicopter at an altitude of 2008m and target at 8m), Ground speed of 159km/h, Air speed of 144km/h (40m/s) on a level flight (0° pitch).

As I had a lot of issues with the replay so I marked the time with a chronometer and used the average of 3 tests per bomb while in Active Pause.

In conclusion;

• one should use the Θ=21s on the Bombing Sight Tables from the Mi-35 Manual for all Bombs (HD M-54 and LD M-62) and Cluster Bombs
• maybe the Θ=25s could be used for the KMGU-2 Bomblets Dispenser.
• I'm still looking for the real Characteristic Time for those bombs to compare with DCS.

Hey again Quati. Thanks again for this test. I am happy to see this graph you made. But I am very surprised. That RBK is so much faster then KMGU, despite using similar submunitions if you pick AO. 
 

But yes, 25 second tables for KMGU sounds right. And as you said, it is surprising how flat nosed and M62 variants did similarly. It really does appear that 21 second is the average time for a bomb to fall from that height and speed

 

[Tarres]

Trying to operate the sight and the controls, but.... where is the light in the PKI frame that comes off? 

[AeriaGloria]

4 minutes ago, Tarres said:

Trying to operate the sight and the controls, but.... where is the light in the PKI frame that comes off? 

I honestly have no clue. Both the Russian quick start guide, of which there’s an English translation of on user files. And my real life Mi-24P manual says there is a “light in the PKI frame signaling the CPG to release bombs” 

[Tarres]

Yes, same here. Maybe WIP.

[AeriaGloria]

Just now, Tarres said:

Yes, same here. Maybe WIP.

Perhaps it is. Best case would be if Petro could do it. We would select a target or spot to bomb, Petro would tell us the altitude and speed to maintain that closest matches our current speed and altitude and fits one of the values in the tables closest to our speed and altitude, we have to manually adjust for side wind drift using drift gauge, Petro would automatically adjust for forward/backward wind component, and release when ready and hopefully hit if we follow the parameters close enough and correct for side wind correctly 

But I doubt that would happen 

 

 I was reading the Mi-24V manual, it’s turret in the front has the same auto CCIP system our ASP-17V has, where it uses radar altitude, attitude, wind components from doppler, AOA and side slip from DUAS air data probe all together to calculate solution. Except in Mi-24V CPG it also works for bombing. CPG simply aims turret sight at bombing target, and as long as radar altimeter sees something the VSB-24 ballistics computer will drop bombs when the proper location is reached. I don’t know if it was able to correct for wind that way, but damn it was fancy. The CPG in the V even has a dial to adjust target altitude in relation to current terrain radar altimeter sees +/-250m!!

 

 I love the P, I’m glad we got it over any other variant. We have the biggest gun combined with retractable gear and big wings, no other variant has that. But the V would’ve certianly been fun as well even if not as much fun, with a 12.7mm gun that shoots as fast as a Vulcan with auto CCIP and automatic bomb release. The turret since it was from Tu-16, also worked as a gyro gunsight for air targets! 

[fargo007]

On 5/3/2022 at 5:45 PM, Avimimus said:

From the one report I've read... the crews in Afghanistan learned to do it intuitively... like a WW2 fighter-bomber pilot. Some reportedly became quite accurate after they got enough experience.

Part of me still wants the MBD racks so we can carry the 10xFAB-100 bomb load that was used occasionally in Afghanistan.

I find it particularly amusing as this was the exact bomb load of some bombers which carried earlier versions of the FAB-100 during the Great Patriotic War / WWII...!

I wound up working out my own bombing tables based on sight angle, fixed altitudes and speeds.

I started with the tables in the manual but found them not to be accurate so I tuned the angle for each until the impacts roughly matched the release point.

[AeriaGloria]

3 hours ago, fargo007 said:

I wound up working out my own bombing tables based on sight angle, fixed altitudes and speeds.

I started with the tables in the manual but found them not to be accurate so I tuned the angle for each until the impacts roughly matched the release point.

I would be very interested to see what you found. Since I always fly in multiplayer, and have no CPG, I can’t use the timers. Since I can’t use the timers, I can only do a fast release  at low altitude where I can see the target. And becuase it’s at such low altitude, you have to use FAB-250 to not get fragged. 
 

300 kmh, 100m, and 7 degree depression for FAB-250 

300 kmh, 100m, and 6 degrees for RBK, KMGU. 
 

There’s no way you can be at 250 kmh, and still see what the bomb falls on at release point, without being so low you get fragged. Once we get functional bomb fusing options, should open up the ability to use FAB-500 at low altitude, and being able to fly at 250 kmh (opening up use at higher temperatures/altitudes) and being lower to compensate. 
 

Quait has his tables showing 21 seconds is best for bombs, and 25 second tables best for cluster. For regular bombing. I do wonder how these 250 kmh 100 m and 150 m tables from ED manual works out 

Interestingly enough, the ED table for the 250 kmh 100m launch shows a smaller value. But manual operator drop also says angle -3 degrees, which I take as saying “your bomb depression angle is taking into account the nose being -3 degrees below the horizon in order to maintain this speed. As for 160 kmh tables it says +[.5 degrees, and 0 for 200 kmh tables. Why the pilot table doesn’t account for it idk, but if anyone wants to test may be interesting. What I came up for at 300 kmh and 100m takes into account the nearly -10 degrees nose attitude needed. The third picture is the table the ED one is likely taken from, with addition of cluster bombs/25 second values if someone wants to use those. There’s also drift angle correction values that I hope make it into the Ed Manual. 

 

What would be ALOT of fun to use for low altitude and high speed bombing? If the RBK-500U actually had a functioning parachute. Would be so much fun 

Edited May 28, 2022 by AeriaGloria

[fargo007]

The dope I came up with is based on level flight, sight angle, fixed speed. Bomb release being handled by the operator. 

Doing it from the back seat is always going to be "hamhock"  or seat of the pants at best, since you have no way to aim. 

I worked up three different "standard" profiles that work reliably enough that I can put bombs close enough to either destroy or damage a transport truck on every run if I do my part.

This was with the FAB 250kg bombs, but I expect the 500kg will be similar.

I did not get the experience that bombing from above 300m AGL will yield practical accuracy so this was the absolute ceiling I decided to pursue. Above this and you're pretty much using a stopwatch.

I chose 250kmh because it's quite fast, which as you point out is a factor in not getting blown up by your own bombs.

The way this is done is to transfer flight & weapons control to the operator for the bombing run, and have the pilot monitor speed and altitude for consistency while the operator focuses on lineup and trim.

nullYou also need to consider slope on the terrain and adjust accordingly.  Another thing is this is based on actual release, not when you push the button. There is a small delay.

 

Edited May 29, 2022 by fargo007

[AeriaGloria]

2 hours ago, fargo007 said:

The dope I came up with is based on level flight, sight angle, fixed speed. Bomb release being handled by the operator. 

Doing it from the back seat is always going to be "hamhock"  or seat of the pants at best, since you have no way to aim. 

I worked up three different "standard" profiles that work reliably enough that I can put bombs close enough to either destroy or damage a transport truck on every run if I do my part.

This was with the FAB 250kg bombs, but I expect the 500kg will be similar.

I did not get the experience that bombing from above 300m AGL will yield practical accuracy so this was the absolute ceiling I decided to pursue. Above this and you're pretty much using a stopwatch.

I chose 250kmh because it's quite fast, which as you point out is a factor in not getting blown up by your own bombs.

The way this is done is to transfer flight & weapons control to the operator for the bombing run, and have the pilot monitor speed and altitude for consistency while the operator focuses on lineup and trim.

nullYou also need to consider slope on the terrain and adjust accordingly.  Another thing is this is based on actual release, not when you push the button. There is a small delay.

 

 

Interesting that you got 18 degrees for 250 kmh and 100m. Becuase the manual says 14.75 degrees taking into consideration the 3 degrees nose down needed. I’ll have to try it from the pilot seat considering the ASP-17V can depress 17 degrees

[fargo007]

This is based on level flight and level release attitude. Having the operator do it is far more accurate than the pilot.

[AeriaGloria]

4 hours ago, fargo007 said:

This is based on level flight and level release attitude. Having the operator do it is far more accurate than the pilot.

Yeah I’m just curious since the manual tables I take these from are also level flight, but 250 kmh cannot be maintained without about -3 degrees nose down. Also found 200m ones, with almost identical difference from yours compared to 100m ones, perhaps the delay between button press and release is that big of a deal? Also I guess since your test is tailored for FAB-250, and they fall with slightly less then 21 second characteristic, that it makes sense your tests would show a little bit higher depression then practice bombs with exactly 21 second characteristic. Excited to try your tables myself!!! 

I would think the pilot and operator accuracy is identical up until needing more then 17 degrees depression, since operator can go up to 35, and needing timers since operator has those. Pilot also has the drift gauge, and the manual has a table to show you correction needed for certain drift angles. I would assume, that for CPG, the pilot would handle the lateral wind drift correction themselves, while the CPG does longitudinal drift correction.l with pipper depression/timers. 
 

And I attached the wrong drift angle correction above, it seems that table is for a direct degree to mils conversion. But here I found an actual table for level flight correction using the drift gauge. Surprisingly for under 500m, and 21 s characteristic bombs, the correction is 0 unless you have fairly large drift. 
 

Out of curiosity, was your test with 0 wind? 

[fargo007]

I did all testing with no wind so as not to have a variable, but I doubt it will be significant unless we're talking substantial wind. The bombs still land close enough with this short of a fall to create damage.

I don't think there's any comparison in accuracy between pilot and CPG. 

For the pilot to release bombs, the target will be way out of view at the time of release, whereas for the operator, the target is visible in the sight before, during and after release, and there is no chance for lineup error. It's just much more precise.  Give it a try!  We actually have a mission today where the Mi-24's are dropping bombs.

Edited May 31, 2022 by fargo007

[AeriaGloria]

On 5/17/2022 at 1:10 AM, Tarres said:

Trying to operate the sight and the controls, but.... where is the light in the PKI frame that comes off? 

 

On 11/26/2021 at 7:06 AM, fargo007 said:

Thanks, I am on my way to sorting it out!   

 

Now I need to figure out why all the bombs drop when the operator does the bombing, and only one at a time drops when the pilot does it.

I figured out where the frame light is that lights up when the onboard timers calculate. It is above the PKI sight attached to the roof. Can’t be seen when the sight is close to 0 degrees but easy to see when sight is in bombing position. 

I tested it and it works, set time on timers, flip calculate switch, and light turns on at specific time!!

So with this, we should be able to use the 21 second tables in the manual I attached earlier as intended 

Edited June 22, 2022 by AeriaGloria

[Tarres]

Thanks a lot!

I´m doing some tests but I´m unable to achieve the "light on" release indication.

.- Set as CPG

.- Assumed weapons control

.- Select bombs.

.- Set angle and interval like in the data sheets we have.

.-Set the counter to on when target disappear from PKI.

No light indication...

I think that I ´m doing something wrong.

Any idea? 

[AeriaGloria]

2 hours ago, Tarres said:

Thanks a lot!

I´m doing some tests but I´m unable to achieve the "light on" release indication.

.- Set as CPG

.- Assumed weapons control

.- Select bombs.

.- Set angle and interval like in the data sheets we have.

.-Set the counter to on when target disappear from PKI.

No light indication...

I think that I ´m doing something wrong.

Any idea? 

That is weird. I do know you can click the timers to “raise” the dial, I think this acts as a lock to allow you to lock the adjustment. 
 

By “set the timer to on” when target passes center of PKI, you mean you are flipping the switch in between the dials that says “calculate?” Also, your switch below the counters that moves left and right selects which timer you are trying to use. So if you are say using the left time, you need to select the switch below the timers to point towards the left timer, have it at the time you want (like it sounds like you did), then flip the “calculate” switch inbetween the timers to start them the moment the target is in center of PKI. 
 

But it sounds like you did all that? 

Here is a picture of the timers from the Russian quick start guide translated to English available on user files, if using the left timer you need the switch below it (labeled 2 here) to be left, then switch “calculate” (number 3 here in the picture) up when target passes PKI. That’s what you are doing? 
 

You would think they would set it so pressing weapon release could start timers…. What I did was bind the “calculate” switch in between the dials to turn on the timers to an easily accessible button on my HOTAS. I’m going to try it right now in the Kodori Storm instant action mission, test the new anti icing and bombing at same time. 

[Tarres]

I´ll do more tests.

Yes, I´ve done all the indicate procedures.

Some user error I suppose.

[AeriaGloria]

13 hours ago, Tarres said:

I´ll do more tests.

Yes, I´ve done all the indicate procedures.

Some user error I suppose.

I tried it again. Weapon systems have to be armed and energized. It doesn’t matter what position the weapon selector is in

I tried it and was pretty accurate. Atleast relatively. Best accuracy is going to be low enough to not need timers of course 

It’s also very difficult to try and fly and bomb at the same time from CPG, you can see your instruments and the bomb sight when heavily depressed at the same time.