Ракеты в DCS

[GGTharos]

No, it's quite under-modeled.

 

When USAF pilots says 'simply pathetic', those are strong words.

 

In fact I also think R-27ER in Chizh's image is a little under-modeled. navailable at that range IMHO should be 3, not 2 :)

 

You talk about stock 1.2.6 AIM-7 or no? If first, Sparrow is ovemodelled too.

Edited September 29, 2013 by GGTharos

[volk]

Like I said, loft IN GAME is poor and can waste missile energy instead of preserving it, so I would not use it as a measure. (Also, loft in minizap is very, very simple, but it gives you an idea of un-optimized ballistics)

First, loft trajectory is not clear ballistic trajectory with no lifting and control surfaces forces like flying bullet. Missile flies on specific intercept trajectory and receives correction data. It uses in very far distances, and what happens with Pk in case of some target maneuvering? And we don't know Pk for this scenario, may be it is very poor. May be this is for some specific scenario like intercept bomber attack (Tu-22s with nukes). At least I don't know successful big-range loft shoots in RL in fighters kill intercepts.

As you can see from the pictures, if R-27ER used loft it would gain more than 20km range. With loft-glide logic, probably close to 30km gain.

I can't understand it. And try to use more correct data for minizap, Isp = 235 for ER.

Regarding manual loft: Not necessary. Maybe in old software, but you can find youtube video of AIM-120 lofting all by itself, from straight and level flight.

Can you give a links to videos? Edited September 29, 2013 by volk

[volk]

When USAF pilots says 'simply pathetic', those are strong words.

We work with docs, not with words. If pilots says anything, Let them tell it yourself.

navailable at that range IMHO should be 3, not 2

What should be 3?

The proof that AIM-120B,C must outrange R-27ER (When AIM-120B,C is using LOFT) is just physics...As you can see from the pictures, if R-27ER used loft it would gain more than 30km range. With loft-glide logic, probably close to 40km gain.

You want to say that AIM-120 have more ranges, for example 40 and 50 km? Edited September 29, 2013 by volk

[SAB]

Сорри, я забыл что крайний конфиг AIM-120 в 1.2.6 не попал.

Выкладываю в первый пост. Берите данные по AIM-120 оттуда.

:)

 

Попробовал так гораздо лучше, а то в текущем 1.2.6. 120с просто "Агонь"...

[GGTharos]

As you can see, so much time was spent just trying to tune R-27. This should tell you something about the quality of docs.

 

The only truly useful doc in this respect is the AIM-9L doc.

 

If pilot says anything, you should probably listen. I know for a fact that at least in USAF they have very, very detailed information about their own missiles, and threat missiles which they look at and brief for each flight. These guys really know what they're talking about.

 

If you want to ignore them because you have docs which only tell you DLZ but not missile performance, I would say that your logic is in error.

 

This 'we do not work with words' mantra is very funny when applied to information that you need to model missiles. Not all of it comes as 'docs'. :)

 

We work with docs, not with words. If pilots says anything, Let them tell it yourself.

[GGTharos]

First, loft trajectory is not clear ballistic trajectory with no lifting and control surfaces forces like flying bullet. Missile flies on specific intercept trajectory and receives correction data. It uses in very far distances, and what happens with Pk in case of some target maneuvering? And we don't know Pk for this scenario, may be it is very poor. May be this is for some specific scenario like intercept bomber attack (Tu-22s with nukes). At least I don't know successful big-range loft shoots in RL in fighters kill intercepts.

 

Why do you think loft was added if it's just 'poor pk'? Long-range shots aren't always possible for practical reasons that don't have to do with the missile (time required for identification, not shooting unless a border is crossed, etc), so that you won't find long range shoots in RL is normal. Lofting is also used for SAMs :)

 

I can't understand it. And try to use more correct data for minizap, Isp = 235 for ER.Can you give a links to videos?

 

My mistake, but if ISP is only 235, I must decrease drag even more.

 

Look at 3:55, watch the smoke.

 

 

What should be 3?

 

Available g. Either lift is too low, or speed is too slow.

 

You want to say that AIM-120 have more ranges, for example 40 and 50 km?

 

To try and be very clear, think about this ...

 

R-27ER with no loft: Range is 60km (in the scenario we know)

R-27ER with loft: Range is 90km (+30km range gain) in the same scenario

 

AIM-120 with loft will outrange R-27ER at the same altitude because of loft. I can see low altitude being an exception, because you can't get to 'thinner air' fast enough, so you shoot straight.

 

At very high altitude, the AIM-120 can loft up to an altitude where the fins are still marginally effective (if you go higher, the missile is no longer under control) so there is a practical limit to maximum loft altitude.

 

Also, there is a very practical limit of missile maneuver: Less g available the higher you go, so speed of intercept must be higher.

 

In addition there is flight control time limitation.

[volk]

The only truly useful doc in this respect is the AIM-9L doc.

Agree with this totally.

If pilot says anything, you should probably listen. I know for a fact that at least in USAF they have very, very detailed information about their own missiles, and threat missiles which they look at and brief for each flight. These guys really know what they're talking about.

I don't know, how to bring pilots words in game. May be russian pilots, who tested R-77, talk that it fly more fast too? May be there are range chart for launches in target rear hemisphere and we must 'up' it like we try to do it in ER case? Now we only have some Chizh information for '50 km range' and use it for 'worst ER scenario 1100/1000 (even not R with 1100/900)'.

[GGTharos]

If they tell you that the missile is too slow, you should listen. They can't tell you what speed to use, but you at least know that something is wrong, and this is very important.

 

I can tell you right now that for example, AIM-120 rocket ISP > 260. Will I be able to prove it? No. Why am I certain? I won't tell. I won't ask for it to be this way in the game, because I cannot prove it, but I can at least show you that in terms of range, loft function changes things a lot.

 

Keep in mind, that now we enter the world of missile navigation, not just rocket power. R-27 is 'easy' because it flies straight at a head-on target, same with AIM-7.

 

AIM-120, R-77 much more difficult because they use special flight paths with optimizations that we do not understand or know about.

 

So now we have the problem that we cannot directly compare say, AIM-120 and R-27ER (where we can do so for R-27ER and AIM-7).

 

The best you can do is make some assumption about the drag after setting up a known missile, some educated assumption about rocket power, and fire it straight (without loft) to see what it does.

 

Agree with this totally.I don't know, how to bring pilots words in game. May be russian pilots, who tested R-77, talk that it fly more fast too? May be there are range chart for launches in target rear hemisphere and we must 'up' it like we try to do it in ER case? Now we only have some Chizh information for '50 km range' and use it for 'worst ER scenario 1100/1000 (even not R with 1100/900)'.

[volk]

Why do you think loft was added if it's just 'poor pk'?

Because it is not very good idea - operate in missile limits (Rmax1 and even beyond) against maneuvering targets. IMHO. Theare are specific range for lift. As I read in F-16MLU FM.

Lofting is also used for SAMs

We don't know about ranges for loft and non-loft trajectories. And scenarios for it (target type and other conditions).

if ISP is only 235, I must decrease drag even more.

we have 235 for ER.

Look at 3:55, watch the smoke.

Look to what? I can't understand what about you talk.

Available g. Either lift is too low, or speed is too slow.

regarding gs - Chizh have some instruments to see this in game. We only may to check for range hit/no hit situation.

R-27ER with loft: Range is 90km (+30km range gain) in the same scenario

...

AIM-120 with loft will outrange R-27ER at the same altitude because of loft.

First, minizap is not hard proof like AIM-9 time-speed charts. May be errors in calculations there.

Also, there is a very practical limit of missile maneuver: Less g available the higher you go, so speed of intercept must be higher.

Target altitude is const for lift/non-lift scenarios and missile available g's should be equal in intercept stage. Edited September 29, 2013 by volk

[volk]

If they tell you that the missile is too slow, you should listen.

If they tell for us something with digits, we should listen.

The best you can do is make some assumption about the drag after setting up a known missile, some educated assumption about rocket power, and fire it straight (without loft) to see what it does.

I think the best way to check missiles like we did it for previous cases to understand what we have.

[GGTharos]

Because it is not very good idea - operate in missile limits (Rmax1 and even beyond) against maneuvering targets. IMHO. Theare are specific range for lift. As I read in F-16MLU FM.

 

IMHO:

Rmax1 is long because of loft. Loft is used where it is useful. At short ranges it only delays the arrival of the missile.

 

We don't know about ranges for loft and non-loft trajectories. And scenarios for it (target type and other conditions).

 

we have 235 for ER.

 

Look to what? I can't understand what about you talk.

 

Sorry, I forgot to include link:

3:55, look at the smoke. There are better videos, from longer range, but I don't know where they are right now.

 

regarding gs. Chizh have some instruments to see this in game. We only may to check for range hit/no hit situation.

 

Yes; actually, as a feature request, I wish this debug info was made available in standard build. Also, showing radar info like in the debug mode :) The latter is super-good for educating new pilots on how to use the radar :)

 

First, minizap is not hard proof like AIM-9 time-speed charts. May be errors in calculations there.

 

Minizap uses basic physics principles. It is not perfect but it is enough to compare similar scenarios. I actually talk with the person who created Minizap. He has created another version that is not available to the public because minizap was not accurate enough, but the results for those scenarios are the same.

 

Target altitude is const for lift/non-lift scenarios and missile available g's should be equal in intercept stage.

 

I am not talking about the target in this case, but about the maximum practical loft altitude. The missile must arrive at the target with say, 3g available, but during the loft stage, it must not go so high that it will be uncontrollable.

[Chizh]

The loft has advantage when it is performed correctly, that is with an g-load approach to zero. In this case the lift-dependent drag is approach to zero too.

Unfortunately in the game such guidance logic isn't implemented yet. Ingame loft do not bring noticeable advantages.

[GGTharos]

No, you listen even if they don't tell you digits - and why?

Because they know. They can't tell you, but they know. They are the experts.

 

At minimum you then know that you need to find some additional information.

 

If they tell for us something with digits, we should listen.

[GGTharos]

That is correct, but I also believe that the current iteration of the missile will not be able to get correct performance even if you had correct loft.

 

I think correct loft is passing through target altitude with 0 AoA (not 0 g, but I could be wrong) and then optimized speed-sustaining dive to target, but even this description is too vague.

 

The loft has advantage when it is performed correctly, that is with an g-load approach to zero. In this case the lift-dependent drag is approach to zero too.

Unfortunately in the game such guidance logic isn't implemented yet. Ingame loft do not bring noticeable advantages.

[volk]

3:55, look at the smoke.

May be. It can be shoot to high fly target too.

[volk]

No, you listen even if they don't tell you digits - and why?

Ok, let reduce (based on their words) Cx from 0,5 (example) to 0.3. Or 0.35? No, no, I believe that it should be 0.038. Or 0.028... And 0.032 for that missile too... What is correct?

They can't tell you, but they know. They are the experts.

Where they are (in forum space :), this one or other) and their words?

At minimum you then know that you need to find some additional information.

I know we need more information in any case - today and tomorrow. Everything is subject to change - if we find reasons (data) for it. Edited September 29, 2013 by volk

[Chizh]

That is correct, but I also believe that the current iteration of the missile will not be able to get correct performance even if you had correct loft.

 

I think correct loft is passing through target altitude with 0 AoA (not 0 g, but I could be wrong) and then optimized speed-sustaining dive to target, but even this description is too vague.

Of course 0 AoA = 0 g, for missiles.

The main task is a calculation of initial angle of departure. Then missile go to the point of active guidance with 0g and perform terminal homing.

Edited September 29, 2013 by Chizh

[RYSLAND]

Люди, это русская ветка форума. Хватит басурманского. За писанину на русском на западных форумах банят, а тут прямо раздолье. GGTharos, не умеешь по-русски, пиши через переводчик.

[volk]

Люди, это русская ветка форума. Хватит басурманского. За писанину на русском на западных форумах банят, а тут прямо раздолье. GGTharos, не умеешь по-русски, пиши через переводчик.

Давайте без этого. ИМХО без разницы - русская тема или не русская. Меня не банили, когда я писАл по-русски в английской теме. Главное, чтобы по теме. Не надо использовать переводчик, пусть лучше каждый пишет на своем родном языке, так понятнее.

Кстати он сам модератор, если что :)

ps. Кстати тему читают не только русскоязычные пользователи форума.

Edited September 29, 2013 by volk

[volk]

Результаты AIM-120B из #1. Прирост скорости

h = 16000 м, Vи = 1800 км/ч составил 922-936 м/с (4 пуска)

Дальности в ППС.

10000 м

 

 

 

 

 

5000 м

 

 

 

 

 

1000 м

 

 

 

 

AIM-120B.zip

Edited September 29, 2013 by volk

[volk]

Прирост скорости AIM-120C

h = 16000 м, Vи = 1800 км/ч составил 1034-1038 м/с (4 пуска)

AIM-120C.zip

[volk]

Не знаю, сюда или в баги. Обнаружилась проблема. Нужно провести тесты в домашнем онлайне. Поднимаю сервер (галка "общественный сервер" снята), запускаю простую миссию - 2 клиента (соответственно один из них будет выбран сервером) и наземный юнит, соединяюсь клиентом и максимум через полторы минуты получаю на сервере окно "не могу подключиться". У клиента "соединение было разорвано". Причем если клиентом не соединяюсь, то сервер не падает. Пинговал 10 минут интернет-сервера - ни 1 потери пакетов, пинг стабильный. В сетевом экране для DCS.exe разрешена любая активность.

Что я делаю не так?

Edited September 29, 2013 by volk

[Lans]

Могу подключться к тестированию. Чтобы не переводить через переводчик эти англоязычные диалоги, скажите какие проблемы и чего потестить и подработать. Р-27ЭР закончили, а Р-27Р и соответствующие тепловые ракеты?

[Chizh]

Если по Р-27ЭТ возражений нет, то буду переносить в проект.

http://forums.eagle.ru/showpost.php?p=1885562&postcount=4027

 

Далее Р-27Р и Р-27Т.

[Lans]

Если по Р-27ЭТ возражений нет, то буду переносить в проект.

http://forums.eagle.ru/showpost.php?p=1885562&postcount=4027

 

Далее Р-27Р и Р-27Т.

Что касаается меня, ИМХО все что могли в Р-27ЭР доработали.