tavarish palkovnik

Few more pictures of R-77M appeared

This is the best rear view of R-77-1 that I found, and to be in some normal focus to allow taking measuremets. Seems like throat in R-77-1 could be a bit more tight, diameter of seal (сопловая заглушка) from this photo is something about 50mm Seal can be installed in various ways -> but I think this last one (bottom one) is the most likely how it is fixed in nozzle. That means that throat is more likely 40mm what is kind of less then in R-77, and exit diameter is something like 148mm what makes initial expansion ratio 13,7 and that is in range of R-77. But 40mm throat diameter could result that this motor works differently, propellant must be with lower burning rate, otherwise motor would blow out Slower burning -> longer burning Total impulse is still in range, about 14300 kgs at sea level and 15500 at 10km And this longer burning motor gives very nice push in lofting -> It would be nice if there is some video which can give clue how long motor burns, but I haven't managed to find some

Yes, that’s it, always some polynomials which define trajectories to have maximal velocity when rocket reaching target and to be kinematically released when starting to chase target

I think I will need to remodel a little bit my programs for trajectories. In all previous cases (mostly focus was on R-27R and R-27ER) I’ve never managed to fully match all envelopes of launching, usually at 10km I was very close to match it, but on higher altitudes I always had a little bit underperformed results. Reason is most likely in incorrect involvement of this overload reserve (запас перегрузки или дополнительное нагружение). I was simply just making sum of kinematic overload, for example 1G for leveled flight, and 3G as reserved overload, making total of 4G, and used same for all altitudes. But most likely it doesn’t work that way, it is not just sum and most likely запас is not same for all altitudes. This is not related to air-to-air rocket but principles could be same or similar. In this case for targeting at altitude 10km calculating overload is 3,1 (total ones) but for 15km 2,7 , 2,2 at 20km etc etc, and that same principle could solve my mismatching.

Attempt to reconstruct this case, very low launcing velocity, fair altitude and very high distance to target. If it's true, number in circle present seconds till impact, so 100 seconds which is very long travel. I have no clue where is target on altitude and how fast it is so let's consider it to be same. Several options: 1) levelled flight 1G overload plus 3G reserve 2) initial lofting maneuver and ballistic trajectory but keeping 3G reserve Both of these cases are pointless, not even close to reach target 3) initial lofting maneuver, then ballistic trajectory without any overload and/or reserve and at the end gliding with 1G overload with included 3G reserve Only this thrid case can bring rocket that far and also to have at least some velocity at the end Approximately 67 seconds of passive flying object, with locked fins in zero position, with no lift force whatsoever. I have no clue could it be case, it is completly differnet approach compared to other Russian rockets, I mean on absence of this overload reserve. But only this way I manged to drag rocket that far

Yes yes, I understand this was drag with AoA=0 but Cn function will be needed as well to make some external ballistics If you have time push the rocket at sea level 1, 2 and 3M and push it to 15 degrees to see Cn values. These 3 reference points should be enough

One very questionable method but result that I got is actually what I was expecting it will be Determination of hole's diameter based on two different reference measures and than finding third one which dropped out to be in level of what is in R-77 motor So it could be something like this, R-77 and R-77-1 nozzles, initial area ratios 14 and 10 respectively About propellant grain configuration, I think both motors have same 5-point star grain, here signs of slivers can be seen very nicely

This looks nice and fair Lift coefficients will be needed as well, either Cy f(M) or Cn f(alpha), three Mach numbers will be enough (1, 2 and 3M)

Anyone has idea (some tools) how to figure out what could be hole's diameter. Picture frame (focus) was not taken very happily and I think diameter is not so small as it looks on first view. R-77-1 of course is on picture. Actually I don't even know nozzle exit diameter so that info would be also appreciated

That is good point and question in same time. Do we have actually valid document that give 190kg to 77-1 ? For R-77 sources say 175-177kg and extra 110mm (R-77-1) supposedly made total of 190kg. Now new extra of 300mm made R-77M but this extra 300mm I count only as extra length of motor and that is just propellant and chamber casing what is 15-16kg

Few more words about new motor...of course dual impulse concept is just thought what could be inside. However sometimes the most simpliest is the most realistic and just simple single thrust motor should not be excluded, motor in form of regular R-77 motor, only on steroids Why I didn't exclude this...calculated first impulse that I got simply is not powerfull enough to push rocket in lofting. Not enough kilograms of force to lift rocket without significant loss of velocity. It's nice to have second impulse but pointless if first one didn't make good start. This is however someting else, this is very powerfull and potent motor. Still not very good solution for levelled flight (same 10km altitude and 500m/s starting velocity) -> but...this motor can easily lift starting 200kg in very nice lofting without lossing too much in velocity Dual thrust concept beside these two remains, but I really don't see such a long 200mm caliber motor in dual thrust concept and I'm not going to consider it

Don't advocate for others...others will do it themselves if feel as needed. Out and over

In any case we will know more and better when first motor case appears, when we see on it specific marks which will give answers. This is actually nothing new, more then 20 years is how much this motor is in connection with multy impulse concept

I thought it will be perfectly clear, anyway, red curve is case if second impulse would be started immediately after first one is finished. Green curve is case if second impulse would be started in 25th second and of course blue curve is with started second impulse in 45th second. One more realistic situation, levelled flight at 10km and starting velocity 500m/s First and second impulses one after another, something like dual thrust motor...and case if second impulse would be started when velocity drop to approximately 1M Combined cases -> Obviously dual impulse is with intention to make rocket with more potential in time when it counts the most, in time when target suppose to be hunted. Fact is that such concept, I think in most cases, gives shorter range and rocket is less agile considering total flight time, but when it matters then such rocket is with potential

I've never made fun with @MA_VMF !!! Actually I apprciate his work a lot

For drag coefficient function I’m quite confident it shouldn’t be something drastically different than presented. Not first configuration I calculated in old fashioned way This other issue is open…60 seconds or 120 seconds and are they changed principles (I hope they didn’t) to match cowboys in exaggerating with air-balls hitting one in hundreds case For now, at least to me, this is reality

Пуск…ракета пошла ! 15km altitude scenario, leveled flight, 3G reserve included, some theoretical top high starting velocity, starting weight 200kg. And ignition of second impulse right after first finish, in 25th second and in 45th second. Pictures show everything so no need to waste words. This exact, I think, rocket is described in one of the patents. There they mentioned that realistic thrust of second impulse could be 1000kg and weight of rocket, after both impulses are out, in level of 120kg. Based on the text, idea is to start second impulse in way that it finishes couple seconds before rocket reaches programmed point of impact in target. And…NO, this rocket doesn’t reach distances 100, 150, 200km as internet already started to drop nonsenses

Ready for pusk

First iteration about this new one

Already in active usage

New model from R-77 family starts to fly. Looks something like 300-350mm longer rocket and if I would give dual impulse to any rocket, this one would be that

When mentioned Sparrow, I don’t know if already had conversations about this drag function attributed to Sparrow Don’t like this “all altitudes” but never mind, differences are not so dramatic. But this function without reference area is not much useful… In any case, it should be area of two fins making peak as 0,84 counting with body cross section area

I was questioning why and how comes there is no yet on internet drag function for R-77. Really it is not easy to calculate such configuration, actually I'm giving up of it. Simply I don't have enough literature to make some reasonable, at least approximative calculation. All other rockets with normal fins can be quite easily calculated and results were not so bad, actually where had valid data to compare, not bad at all. There are several paper works but mostly they have focus on drag of individual fin, and I'm interested in full assembly. I was mentioning base pressure, one of the easiest parts of total drag calculation, but here with grid fins I just stuck and don't know how to proceed. And like said already, I'm expecting this part together with pressure on fins to be significantly higher then what is case with classic fins or wings whatever is in aft zone Few such aft section surfaces, Phoenix, Sidewinder and Sparrow For all these configurations base pressure can be easily calculated, and this ''c'' number (ratio between wing thickness and aerodynamic chord) is for these samples approximately 0,036 ; 0,046 and 0,09. What grid fins make on body base I have no idea ...

@MA_VMF Don't take me wrong but it would be fair to write few words with applied image, otherwise images become ->

New tricks, single image for two different situations ? Bottom is sea level seems like, and top side something higher altitude, and looks like some higher velocity then 0,8 mach number. And I'm very curious to see how this ''blue'' part (vacuuming) will develope with velocities