Ракеты в DCS

[Chizh]

14 часов назад, TotenDead сказал:

В DCS МиГ-31, летящий со скоростью ~2700 км/ч на высоте 20000м пускает Р-33 по равновысотной, равноскоростной, неманеврирующей цели с дальности в ~90км. И это с выставленным условием пуска на максимальной возможной дальности. Интернетная дальность пуска этой ракеты - 120км, предположительно - по классике для высоты в 15км и скорости в 1.5М

ДокУмента, конечно, нет, но скромновато выходит

Главное ограничение этой ракеты - время работы энергосистемы в 60 секунд.

Кроме того там есть запас процентов в 5% на неточность оценки дальности плюс пару секунд на процедуры запуска. 

120 км дальности это скорее всего расчетная величина, по границе возможностей.

[tavarish palkovnik]

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Edited April 23 by tavarish palkovnik

[tavarish palkovnik]

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Edited April 23 by tavarish palkovnik

[tripod3]

Бамп треду баллистических ракет для DCS

[tavarish palkovnik]

Few thoughts about HARM, there is nothing on the internet to be used as solid numbers, I mean how it's motor works in numbers. And I'm kind of stuck with it, seams as close but still final is missing, not sure what to select as final.

There are only few crosscut graphics on the internet, and if those would be same then there will be no doubts but one is different then others, and that one is actually the most serious and the most relevant. Where to place second radial stress relief slot? That change everything in complete, would booster be stronger and sustain weaker and longer or weaker booster and shorter but stronger sustain. Obviously 3 graphics are showing that slot is in area of aft launch hook where motor is hardened and that has sense, usually such dividing in grain configuration is around such hardened place. But fourth one shows different, and although it is only sketch I can't not to take it seriously. After all, this one shows what is the most important in this work, grain configuration, half actually more then half is solved when having that.  

 

 

 

Propellant is known, just common non-aluminized HTPB based propellant, and there are few of such with given characteristics so together with grain configuration and also nozzle geometry which I have measured, it is almost everything on place to have something as output, how it works

 

 

 

 

 

 

For sure, it is something of these two. Both are realistic, both are achievable, both are normal

 

 

Pressure rates are in level of normal, a bit higher in this with stronger booster but still just regular. And this would be force output of these two options at 5km although with nozzle exit diameter of just 128mm there is no some significant gain with altitude

 

 

 

It is nearly same total impulse about 285kNs so both should not be much different in dynamic, only distribution in time is different. I made few drop shots just to see where they are compared one to other, some launches from 2, 5 and 10km from horizontal and then gravity and atmosphere work, also some stupid non-realistic ballistic shot

 

   

 

 

 

 

That's all close one to other, just slight motion adventage of stronger booster but insignificant. So I stuck, and don't know which one is the one. Almost forget to use sample shot what the Chinese gave ...

 

     

 

 

 

Obviously they are about ''blue'' one but I'm not sure in that. I'm kind of more on side of ''red'' one...actually I don't know, it is 50:50. Both like said are realistic only I hate when don't have answer. Blue one is a bit more normal with pressures, it has slot where it would be expected to be, but the most relevant graphic shows different...70:30 for red.

I would like to hear some thoughts, I know there are members here which knows this matter and which are curious as me. By the way, what you gave to HARM in DCS?

 

 

[Маэстро]

Indeed verly lttile of iformation about HARM is availabe. In DCS we have total impulse about 29000s and propellant mass of 127kg, but boost phase is shorther and sustain is longer. I think your estimation is more accurate. Will try to use it for our HARM(if you have no objections:))

BTW. What's the source of AIM-4 Cd figure?

[tavarish palkovnik]

''Red'' model is better to use as sample for consideration of shorter boost-longer sustain. Of course it is connected if propellant type inside is same and I think it is because only TP-H1159 is mentioned as type for HARM. By the way, there is also some doubt is this grain single or there are after all two grains inside. For casting I don't see reason for two grains of same propellant because it looks to me that single one can be done, but who knows. In some similar crosscuts where it is written boost grain and sustain grain (for example in Mk39 Mod.7 motor of Shrike, precursor of HARM) indeed two grains are inside and of two different propellants, Mk58 of AIM-7F also etc etc. I wouldn't be surprised with two grains.

Anyway, I modelled it as single grain and for burning used 1,55*p˄0,36 and for all pressure rates. Unfortunately, for us trying to do this, luckily for constructors of motors, burning rates can be with additives modified to be different for different pressure. So 1,55*p˄0,36 is for range of 1000 psi (69 bar) but for 20 bar or 120 bar it can be different burning exponent and response. It's not easy of course to find answers with many open questions but I really think I'm close with these two options, red and blue.

Simply with shorter boost, motor would go in pressure rates exceeding normal ones, and longer sustain is possible in this grain configuration only if reduce burning rate, and 20 bar pressure is for me some minimum for proper motor operation, lower than that motor could cough and die. On 20 bar it is only something about 4,55 mm/s of burning speed and that is minimum of minimum for reliable work of motor, or I believe that.

If you can, of course I don't have objections, actually I would be glad, try to use these two with your dynamic model to see how it fits to it. Or just one, on principle truth is always somewhere in the middle  

Falcon's drag is from here -> ''Free-Flight Investigation of the Full-Scale Hughes Falcon Missile, D Configuration, to Determine Aileron Effectiveness and Damping in Roll''

Free-Flight Investigation of the Full-Scale Hughes Falcon Missile, D Configuration, to Determine Aileron Effectiveness and Damping in Roll - UNT Digital Library

 

Edited September 11, 2024 by tavarish palkovnik

[Маэстро]

On 9/11/2024 at 2:08 PM, tavarish palkovnik said:

''Red'' model is better to use as sample for consideration of shorter boost-longer sustain. Of course it is connected if propellant type inside is same and I think it is because only TP-H1159 is mentioned as type for HARM. By the way, there is also some doubt is this grain single or there are after all two grains inside. For casting I don't see reason for two grains of same propellant because it looks to me that single one can be done, but who knows. In some similar crosscuts where it is written boost grain and sustain grain (for example in Mk39 Mod.7 motor of Shrike, precursor of HARM) indeed two grains are inside and of two different propellants, Mk58 of AIM-7F also etc etc. I wouldn't be surprised with two grains.

Anyway, I modelled it as single grain and for burning used 1,55*p˄0,36 and for all pressure rates. Unfortunately, for us trying to do this, luckily for constructors of motors, burning rates can be with additives modified to be different for different pressure. So 1,55*p˄0,36 is for range of 1000 psi (69 bar) but for 20 bar or 120 bar it can be different burning exponent and response. It's not easy of course to find answers with many open questions but I really think I'm close with these two options, red and blue.

Simply with shorter boost, motor would go in pressure rates exceeding normal ones, and longer sustain is possible in this grain configuration only if reduce burning rate, and 20 bar pressure is for me some minimum for proper motor operation, lower than that motor could cough and die. On 20 bar it is only something about 4,55 mm/s of burning speed and that is minimum of minimum for reliable work of motor, or I believe that.

Frankly, I do not remeber all assumptions made for my estimation several years ago(and can not refresh them now because all this left on my old PC which i do not have at hand now), but grain shaping obviously was different and I remeber that it has slots through all its length while your variant has round canal in forward section. Currently booster provides about 59kN of thrust for one second(Isp=235s) and sustainer provides average thrust of 11kN for 20 sec(Isp = 226s). Now I'm going to change tehm in the next way: booster - 53.3kN for 3.2 sec; sustainer - 8.4kN for 13.5sec. BTW could you provde Isp or grain mass for every stage for both blue and red variants?
 

On 9/11/2024 at 2:08 PM, tavarish palkovnik said:

If you can, of course I don't have objections, actually I would be glad, try to use these two with your dynamic model to see how it fits to it. Or just one, on principle truth is always somewhere in the middle  

Falcon's drag is from here -> ''Free-Flight Investigation of the Full-Scale Hughes Falcon Missile, D Configuration, to Determine Aileron Effectiveness and Damping in Roll''

Free-Flight Investigation of the Full-Scale Hughes Falcon Missile, D Configuration, to Determine Aileron Effectiveness and Damping in Roll - UNT Digital Library

Thank you!

[tavarish palkovnik]

18 hours ago, Маэстро said:

Isp or grain mass for every stage for both blue and red variants?

First thrust curves for sea level and 10km for reference, Itot=277,5 kNs and Itot=292,5 kNs

 

This is of course weight of propellant with time, initial weight 127kg

 

 

And Isp for sea level and 10km

 

 

 

Your plan 53,3*3,2+8,4*13,5 seems as reasonable, although if we start from pressure rates I'm more for something about 125bar in boost and 25bar in sustain what for ''squared'' profile would be like 47,5*3,5+8,5*13 at sea level and 48,5*3,5+9,5*13 at 10km. Of course decision is yours, this is just thought of mine.

 

Some guys will be disappointed when see values of Isp because it is HTPB and beside that it is American HTPB, but reality and wishes are different. This is non-aluminized propellant, relatively ''cold'' with some 3000K flame temperature, nozzle is as it is, and of course there is no rocket motor which will give theoretical maximum, simply some of total theoretical potential will be inevitable lost, and there are plenty of possible losses       

 

[Маэстро]

On 9/13/2024 at 1:11 PM, tavarish palkovnik said:

First thrust curves for sea level and 10km for reference, Itot=277,5 kNs and Itot=292,5 kNs

 

This is of course weight of propellant with time, initial weight 127kg

 

 

And Isp for sea level and 10km

 

 

 

Your plan 53,3*3,2+8,4*13,5 seems as reasonable, although if we start from pressure rates I'm more for something about 125bar in boost and 25bar in sustain what for ''squared'' profile would be like 47,5*3,5+8,5*13 at sea level and 48,5*3,5+9,5*13 at 10km. Of course decision is yours, this is just thought of mine.    

Thanks! Finally, after making some averaging(since we have no smooth boost-sustain thrust transition in DCS) i set it to 47.5*3.4 + 9.2 * 12.5 at sea level (70kg with isp 235s + 57kg with isp 206s respectively). It's about 2% less total Isp due to lower sustainer pressure now, but all that looks quite reasanable to me(and very similar to aim-7's mk58).

On 9/13/2024 at 1:11 PM, tavarish palkovnik said:

Some guys will be disappointed when see values of Isp because it is HTPB and beside that it is American HTPB, but reality and wishes are different. This is non-aluminized propellant, relatively ''cold'' with some 3000K flame temperature, nozzle is as it is, and of course there is no rocket motor which will give theoretical maximum, simply some of total theoretical potential will be inevitable lost, and there are plenty of possible losses  

Absolutely agreed.

[tavarish palkovnik]

You are welcome @Маэстро 

Of course if something new appears, somewhere, about this motor, to confirm or correct this a bit or…rebut it, I will share it. 

But like you said, it looks quite reasonable and I fully agree. It is backed with quite enough valid inputs so output should not be much different than this, perhaps just in some finesses

[Viper33]

So when will you guys finally update the R-77?

[falcon_120]

Or include a R77-1 for modern time periods

[F-2]

I don’t think we have any aircraft in game that carry it but I do think it would be achievable to make AI assets that could carry it

Su-27SM3 AI should not be different from a Su-27 AI in flight performance 

Mig-29sm same as above

Su-30SM apparently the original desktop simulation was built on the Flanker engine and the demo is available for reference. I have lots on N011m bars for a .lua radar

it would be nice to have even if we couldn’t use it. Sort of like how he have a playable mirage 2000c and an AI Mirage 2000-5.

 

 

[Viper33]

5 hours ago, falcon_120 said:

Or include a R77-1 for modern time periods

No plane in DCS that can carry it outside of maybe AI.

[Chizh]

5 часов назад, falcon_120 сказал:

Or include a R77-1 for modern time periods

No chance at this time

[falcon_120]

Fair enough, I'm happy with whatever i can get (eg. revised r77) :).

Enviado desde mi ELE-L29 mediante Tapatalk

[draconus]

Планируете ли вы работать над ракетами AIM-54 и улучшать их реалистичность?
@tavarish palkovnik представил несколько интересных обоснований, расчетов и данных, особенно касающихся среднего полного импульса, тяги по отношению к высоте, времени горения по отношению к температуре, расчетов сопла и давления. Вот несколько примеров:

Вы ранее приняли и оценили его помощь по ракете HARM.
Спасибо

[Chizh]

34 минуты назад, draconus сказал:

Планируете ли вы работать над ракетами AIM-54 и улучшать их реалистичность?

Да, в плане. Стоит в очереди.

[Katsu]

On 11/29/2024 at 7:49 AM, Chizh said:

Да, в плане. Стоит в очереди.

Были найдены несоответствия, которые было бы интересно проверить в будущем.

@tavarish palkovnik провел детальное исследование ракеты, которое оспаривает разработчик, и кажется, что разработчик не очень хочет сотрудничать, чтобы прийти к консенсусу о том, где им удалось подтвердить производительность (поскольку математически ракета не точна). 
 

 

[tavarish palkovnik]

@Katsu don’t make them to lock this thread as well  and I know they won’t because these guys here are better kind than those ones of “canceling culture”. But never mind, all what had to be said is said and if those HB or whatever companions still want to live in their illusions and some imaginary not existing source, then they can live in it. Unbelievable guys and so shallow in subject which they should know much better in any case

[TotenDead]

8 часов назад, tavarish palkovnik сказал:

@Katsu don’t make them to lock this thread as well  and I know they won’t because these guys here are better kind than those ones of “canceling culture”. But never mind, all what had to be said is said and if those HB or whatever companions still want to live in their illusions and some imaginary not existing source, then they can live in it. Unbelievable guys and so shallow in subject which they should know much better in any case

Выше на графике зоны возможных пусков Р-33, что ты кидал, отмечена перегрузка 4-6. Это значит, что дальности даны с учетом того, что Р-33 гарантированно сбивает цель, маневрирующую в момент встречи с ракетой с указанными G или как?

[tavarish palkovnik]

Так написано, зона пусков с перегрузкой цели от 4 до 6. Если посмотреть на скорость ракеты на конечном этапе, то эти перегрузки цели кажутся правильными

[TotenDead]

В 04.12.2024 в 09:57, tavarish palkovnik сказал:

Так написано, зона пусков с перегрузкой цели от 4 до 6. Если посмотреть на скорость ракеты на конечном этапе, то эти перегрузки цели кажутся правильными

Думаю смысл понял.

Потестил в ДКС, на высоте 17км Р-33 пускается МиГом (Vи = 2900кмч, Vц - 2500кмч, H обоих = 17000м) ровно со 100км максимум, при этом на момент встречи с целью энергии у нее с хорошим запасом.

Судя по графику, в этих условиях ракета должна улетать на 140+км, энергетически в игре это ВРОДЕ БЫ возможно.

Быть может проблема не в ракете, а в самом МиГе? Если что, я выставлял в условиях пуск на максимальную дальность.

[Chizh]

У нее время полета 60 сек. На 140 она никак не улетит. Не говоря уже о падении точности наведения. На таких дистанциях с ПАРГСН делать нечего.