Mi-24P auto ranging and CCIP errors

[AeriaGloria]

I’m going to copy a poste I made on a discord, sorry for the length 

 

“

Sometimes I think the auto CCIP even over flat ground makes rounds go long. Most obvious when fired at max range. I always wondered if I’m the only one to notice becuase I’ve seen no one mention it,

Then I was watching my radar altimeter move even at dive/roll angles below 30 degrees, I always thought it worked fine until 30 degrees, but i think It gets off just enough even at 15-20 degree dive angles to make the pipper go lower then it should be(thinking you’re higher then you are). 

I think I’m not attacking at low altitude as often as it’s meant to, and maybe if I attack lower and dive to attack at shallower angles like 10 degrees it might work better. If that’s really the case that puts my mind at ease, then it’s easy to adjust for high dive angles and just compromise with firing shorter the more you dive and farther away you are, with the difference becoming more negligible at shorter ranges. 

Anyone come to the same conclusion or have thoughts about it? I guess if this is really the case it’s not advanced enough to have a pre-calculated coefficient for how much dive and roll affect the radio altimeter below 30 degrees to use for auto CCIP. 

Also worth noting this affects the gun much less then rockets but still there, the gun needs less ballistic corrections with its flatter trajectory so the errors affect it less. The gun pods have even flatter ballistics then the Gsh-2-30k and are probably affected less, even though the CCIP for gun pods seems to be tuned for the 12.7, since the CCIP doesn’t change angle correction for 7.62 and they hit just a little bit shorter

 

That would also mean if this is true the auto ranging function for things like S-13 or S-24 should be overestimated at higher dive angles, and if this is really the case you would need to wait until the range is a little shorter on the ASP then your table says depending if your angle is 20-30 degrees“

 

any thoughts or people come to the same conclusion? Going to try and test tonight 

 

EDIT: I thought the stated radar altitude limit of correct readings was +/-30 degrees, I found some information for RVU-5 that it’s actually +/-15 degrees, so any dive past that angle we need to eyeball and estimate our own corrections

Edited August 24, 2021 by AeriaGloria

[Avimimus]

I haven't yet seen an explanation as to why it turns on and off (right-hand light)... there is something about attitude, altitude, maybe even airspeed that I don't understand yet.

 

There should be some range errors of course - but if they are small I generally assume it is due to very small changes in elevation.

[AeriaGloria]

On and off? It only works if your diving, the moment your nose is level or above level it turns off. 
 

watch your radar altimeter as you bank beyond 15 degrees and you’ll see significant errors, try shooting anything with a 20-30 degree dive with CCIP and rockets from maximum range or closer and you will see your rounds go very long, if you don’t realize it’s the radar altimeter sometimes you have to get within minimum range before the error is small enough that the rockets hit close enough to your aim point, and if you’re using KOMs it’s even worse becuase they require a direct hit. 

Edited August 25, 2021 by AeriaGloria

[Mins]

9 hours ago, AeriaGloria said:

 

 

 

If the terrain is not level and the target is higher (lower), then the range will be calculated with an error, because the range is calculated by the angle of inclination and the data of the radio altimeter

Edited August 25, 2021 by Mins

[AeriaGloria]

9 minutes ago, Mins said:

если местность не ровная, а цель выше, то дальность не будет рассчитана точно. Потому что дальность рассчитывается по углу наклона в зависимости от данных радиовысотомера

 

- Google Переводчик-

“Я знаю, что CCIP работает точно только на ровной поверхности, я говорю только об ошибках радиолокационного высотомера при оценке высоты с углами крена или тангажа более 15 градусов. Поскольку радиовысотомер дает слишком большую высоту при углах пикирования более 15 градусов, автоматический CCIP считает, что вы находитесь дальше от цели, чем вы на самом деле, поэтому он помещает пиппер ниже того места, где фактически приземляются ваши снаряды. Эта ошибка оказывает меньшее влияние, чем ближе вы находитесь, и для оружия с более плоской траекторией.”

 

 

I am aware that the CCIP only functions accurately over flat ground, i am only speaking of errors from the radar altimeter over estimating height with bank or pitch angles over 15 degrees. Since the radio altimeter gives too high of a height at dive angles over 15 degrees the auto CCIP thinks you are farther from the target then you really are, so it places the pipper lower then where your rounds will actually land. This error having less effect the closer you are and for weapons with flatter trajectories 
 

 

Edited August 25, 2021 by AeriaGloria

[Mins]

5 minutes ago, AeriaGloria said:

 

- Google Переводчик-

“Я знаю, что CCIP работает точно только на ровной поверхности, я говорю только об ошибках радиолокационного высотомера при оценке высоты с углами крена или тангажа более 15 градусов. Поскольку радиовысотомер дает слишком большую высоту при углах пикирования более 15 градусов, автоматический CCIP считает, что вы находитесь дальше от цели, чем вы на самом деле, поэтому он помещает пиппер ниже того места, где фактически приземляются ваши снаряды. Эта ошибка оказывает меньшее влияние, чем ближе вы находитесь, и для оружия с более плоской траекторией.”

 

 

I am aware that the CCIP only functions accurately over flat ground, i am only speaking of errors from the radar altimeter over estimating height with bank or pitch angles over 15 degrees. Since the radio altimeter gives too high of a height at dive angles over 15 degrees the auto CCIP thinks you are farther from the target then you really are, so it places the pipper lower then where your rounds will actually land. This error having less effect the closer you are and for weapons with flatter trajectories 
 

 

 

I understand you now. It is necessary to look at the technical documentation, possibly correct, perhaps not. I do not remember the range of angles so that there is no error, but they should definitely not be large

[Mins]

https://studbooks.net/2359056/tehnika/optimizatsiya_parametrov_radiovysotomer.       Use a translator, I think the text will be clear

Edited August 25, 2021 by Mins

[Mins]

Погрешность измерения высоты по указателю:

· на высотах от 0 до 10 м …………………………….±0,8 м;

· на высотах от 10 до 750 м ………………………….±8% от высоты.

 

 

Нормальная работа радиовысотомера обеспечивается в полете с углами крена не более ±15°.

Edited August 25, 2021 by Mins

[Mins]

42 minutes ago, AeriaGloria said:

 

- Google Переводчик-

“Я знаю, что CCIP работает точно только на ровной поверхности, я говорю только об ошибках радиолокационного высотомера при оценке высоты с углами крена или тангажа более 15 градусов. Поскольку радиовысотомер дает слишком большую высоту при углах пикирования более 15 градусов, автоматический CCIP считает, что вы находитесь дальше от цели, чем вы на самом деле, поэтому он помещает пиппер ниже того места, где фактически приземляются ваши снаряды. Эта ошибка оказывает меньшее влияние, чем ближе вы находитесь, и для оружия с более плоской траекторией.”

 

 

I am aware that the CCIP only functions accurately over flat ground, i am only speaking of errors from the radar altimeter over estimating height with bank or pitch angles over 15 degrees. Since the radio altimeter gives too high of a height at dive angles over 15 degrees the auto CCIP thinks you are farther from the target then you really are, so it places the pipper lower then where your rounds will actually land. This error having less effect the closer you are and for weapons with flatter trajectories 
 

 

 

The sight is more suitable for area targets than a single point hit with a single projectile or rocket

[AeriaGloria]

3 hours ago, Mins said:

The sight is more suitable for area targets than a single point hit with a single projectile or rocket

thank you so much for the link and additional information to confirm my findings. You are correct that I was attempting to use as few rockets as precise as possible from near max range, and that it does do better in area affect. 
 

testing tonight with keeping my pitch below 15 degrees, there is still some error, sometimes it’s perfect sometimes it’s not, it seems to be the nature of the system and well simulated especially considering your information of an 8% error at 10-750m, the lower your altitude the less your error as well. 
 

thank you so much, this answer a lot of my questions, you’re very helpful!!!

[Mins]