Operational Performance Comparison: Viper, Beagle and Stubby

[southerncross]

So yes, it should be "technically possible" for a pilot to make the right turn exactly at the right time in order to evade a missile but as you correctly said this is extremely hard to do, or using your own words a "surgical precision" maneuver is required for this.

Yes, it is complicated to the point I don't know if it is realistically doable to start with. The pilot has what, 10-15 seconds to assess the situation, choose the right tactic and implement it, with maneuver windows of few seconds... Fighter pilots are trained to think damn fast, but still if you don't know this by heart you will not be even able to get started, and then for instance a Meteor instead of an AMRAAM would need a different timing due to different propulsion / speed loss. Difficult indeed.

On the one hand, it again underlines the importance of early detection to have TIME to understand what is going on before acting, like going from 10 secs to 1 minute probably changes everything.

On the other, it makes clear how relevant intellectual support for the pilot can be. I don't know what the MiG is capable of, or what newer fighters manage to do in this regard, but ideally the plane could measure the missile's speed vector and very accurately calculate and suggest the maneuver sequence needed to defeat it. In fact, it would be best if it could perform the maneuver itself! Countermeasure deployment is automatic these days, I don't know if some evasive maneouvers are automatic, too.

Or resuming, while the missile doesn't actually reduce its speed "by itself", any missile turn on the later stages of flight will/should result in an actual speed reduction on the missile (a turn will result on the missile bleeding some of its speed when flying unpowered).

Exactly... and then it should not reduce its speed too much, or it will lose the capability to undercut the fighter's movements at all. With a target at 2.5 M I guess the missile has little margin actually.

[sprstdlyscottsmn]

T:0 -- MiG-31 fires from 75,00ft once it has locked the F-16 at a range of 105nm. F-16 and MiG-31 have a combined closing speed of 0.624nm/sec.

T:28.4 -- F-16 locks and fires from 40,000ft at a range of 87.3nm. The R-37 is currently flying Mach 6.0 in a 6 degree climb through 87,500ft. The F-16 is 80.14nm away slant range and 11.71 degrees off missile boresight. Aimpoint to the F-16 is 64.14nm away slant range and 13.1 degrees off missile boresight.

T:86.0 -- SABR detects incoming R-37. Within 1 second the F-16 begins defensive turn. R-37 is currently in a 24.7 degree dive through 68,600ft at 5.1M and decelerating. The F-16 is 14.89nm away slant range and 6.3 degrees off missile boresight. Aimpoint to the F-16 is 11.16nm away slant range and 0.1 degrees off missile boresight.

T:96.8 -- The F-16 completes its defensive 60 degree turn and has slowed to 1.2 M. Within 2 seconds it begins to turn back to the origional heading at half the turn rate used defensively. R-37 is currently in a 21.1 degree dive through 50,500ft at a speed of 3.3M. The F-16 is 5.85nm away slant range and 22.4 degrees off missile boresight. Aimpoint to the F-16 is 4.74nm away slant range and 0.7 degrees off missile boresight.

T:110 -- The F-16 is now within 26 degrees of it's original heading. R-37 is currently in a 12.4 degree dive through 40,000ft at a speed of 1.36M. The F-16 is 0.06nm away slant range and 65.8 degrees off missile boresight. Aimpoint to the F-16 is .20nm away slant range and 15.9 degrees off missile boresight. The R-37 failed to reach it's target and with a miss distance of 108m is outside the lethal envelope of it's warhead.

I will have to come back and edit this with the AMRAAM shot later

[garrya]

T:28.4 -- F-16 locks and fires from 40,000ft at a range of 87.3nm. The R-37 is currently flying Mach 6.0 in a 6 degree climb through 87,500ft. The F-16 is 80.14nm away slant range and 11.71 degrees off missile boresight. Aimpoint to the F-16 is 64.14nm away slant range and 13.1 degrees off missile boresight. I will have to come back and edit this with the AMRAAM shot later

IMHO, since AIM-120 can reach Mach 6 when launched from F-22, shouldn't R-37 fly faster than Mach 6?

[sprstdlyscottsmn]

IMHO, since AIM-120 can reach Mach 6 when launched from F-22, shouldn't R-37 fly faster than Mach 6?

not necessarily. All existing R-37 stats are from a MiG-31 as the sole (at the time) launch platform. Getting my model to line up with publicly stated performance means it is a relatively long and low burn with a gentle loft. AIM-120D on the other hand is a violent and rapid punch up to max speed and higher loft.

[garrya]

IMHO, since AIM-120 can reach Mach 6 when launched from F-22, shouldn't R-37 fly faster than Mach 6?

not necessarily. All existing R-37 stats are from a MiG-31 as the sole (at the time) launch platform. Getting my model to line up with publicly stated performance means it is a relatively long and low burn with a gentle loft.

Is there any benefit in long burn, gentle loft motor compared to violent motor for R-37?

[sprstdlyscottsmn]

less acceleration G means you don't need as much structure to resist crumpling, for one. That is a bigger concern with a heavier missile.

[garrya]

not necessarily. All existing R-37 stats are from a MiG-31 as the sole (at the time) launch platform. Getting my model to line up with publicly stated performance means it is a relatively long and low burn with a gentle loft. AIM-120D on the other hand is a violent and rapid punch up to max speed and higher loft.

IIRC, R-37 kinematic and motor characteristics are very similar to AIM-54?
AIM-54 when launched from F-15 at Mach 2, 50k ft can reach Mach 5 briefly.

All existing R-37 stats are from a MiG-31 as the sole (at the time) launch platform. Getting my model to line up with publicly stated performance means it is a relatively long and low burn with a gentle loft. AIM-120D on the other hand is a violent and rapid punch up to max speed and higher loft.
less acceleration G means you don't need as much structure to resist crumpling, for one. That is a bigger concern with a heavier missile.

Technically speaking, Mig-31 will be more dangerous if it is equipped with AIM-120, R-77?. From your simulation, it appear that they can fly faster and further than R-37, AIM-54 if they are launched from the same altitude.
Can you test that theory in DCS ?. For example accelerate F-16 or F-15 till Mach 2 then launch AIM-120, then accelerate F-14 till Mach 2 then launch AIM-54. Do they have any kind of function that will allow side by side test launch like that?

[sprstdlyscottsmn]

Don't lump the R-77 into this. That is a short ranged missile compared to the AIM-120D. DCS doesn't model AIM-120Ds either, only C5s, which are two major range improvements below the D. So far, however, it does look like an AIM-120D with the same launch conditions will reach farther than an R-37. Maybe if I lower my standard launch conditions to 55,000ft and 2.2M and recalibrate?

[garrya]

Don't lump the R-77 into this.That is a short ranged missile compared to the AIM-120D.

Isn't R-77 is basically Russian AIM-120?

DCS doesn't model AIM-120Ds either, only C5s, which are two major range improvements below the D

True but they all use the same solid rocket motors and body, I think their burnout velocity are the same. If that isn't correct, speed comparison between AIM-54 and AIM-120C-5 when both are launched from Mach 2,50kft is still very nice.

A development of the earlier AIM-120C, AIM-120D (P3I Phase 4, formerly known as AIM-120C-8) retains the same PN G672798-1 Plus 5 solid propellant rocket motor of the AIM-120C-5 and C-7 variants. However, AIM-120D delivers significant improvement in no-escape envelope and high-angle off-boresight capabilities over earlier variants. The missile now incorporates GPS-aided navigation for improved mid-course guidance and a two-way datalink for greater control over the missile's end-game targeting. The AIM-120D also features revised guidance software to improve kinematic performance and overall effectiveness, and improved electronic counter-countermeasures (ECCM).

Jennings said, "The AIM-120C-5 extended the range of the AIM-120B fairly significantly, by shortening the control actuation system in the back and adding fins to the back end of the rocket motor. That added pretty decent range capability when you go from AIM-120B to AIM-120C-5. The C-7 and the D share the same rocket motor, and the same form, fit, function, size, and control actuation system. And both the C-7 and D have the same rocket motor as the C-5. Throughout AMRAAM's development, there have been improvements into the flight profile of the missile to get to the target. These improvements have led to range increases as well, and the jump from the B to the C-7 was fairly significant. The D can fly slightly farther than the C-7, and the C-7 can fly farther than the C-5. But this range increase is in the order of low double-digit percentages."

https://www.secretprojects.co.uk/thread ... 127/page-2

So far, however, it does look like an AIM-120D with the same launch conditions will reach farther than an R-37. Maybe if I lower my standard launch conditions to 55,000ft and 2.2M and recalibrate?

IMHO, that condition is too low for Mig-31but too fast and high for anything else.

[ricnunes]

Can you test that theory in DCS ?

DON'T USE DCS to test/model Air-to-Air missiles in DCS!
While DCS has many excellent points as a sim, the Air-to-Air missiles in this simulator, specially and namely the AMRAAM is pure crap is all and every possible way.

Resuming, the Air-to-Ground portion (and weaponry) of DCS is good indeed but definitely not the Air-to-Air missiles (actually this is the reason why I rarely use fighter aircraft like the F-15C in DCS)

You would have a much, much better time testing Air-to-Air missiles in Falcon BMS, IMO that is.

[mixelflick]

In the book, "Iranian F-14 Tomcat in Action" a pretty amazing story was told of an F-14/Foxbat encounter..

The story goes that an F-14 was attempting to intercept a Mig-25 and fired a single Phoenix to do the job. The Mig-25 pilot apparently defeated it, not sure exactly how. Unbeknownst to him, the F-14 pilot accelerated to mach 2.2 in hot pursuit. Making it over the border to Iraq, the Mig pilot apparently felt safe and slowed down somewhat.

BIg mistake, because by doing so he signed his own death warrant. The F-14 dispatched a 2nd Phoenix, which obliterated the Mig-25 and brought it down. No word on whether the pilot survived, but if I was a betting man I'd say no. The warhead on the Phoenix is huge.

I think it would be real interesting to know the speed of that 2nd Phoenix. Here we have a mach 5 missile launched at over Mach 2. Had to be at the absolute limit of man, missile and aircraft..

[sprstdlyscottsmn]

Don't lump the R-77 into this.That is a short ranged missile compared to the AIM-120D.

Isn't R-77 is basically Russian AIM-120?

Only in the broadest sense imaginable that it has INS and active guidance. That's it. In terms of range you are looking at somewhere around AIM-120A or B ranges.

The C-7 and D fly farther than the C-5 on the same motor which means..... it is lofting higher and getting a faster top speed as a result of the thinner air before burnout.

[garrya]

Only in the broadest sense imaginable that it has INS and active guidance. That's it. In terms of range you are looking at somewhere around AIM-120A or B ranges.

TBH, I do remember that R-77 kinematic wasn't so good, hence it isn't introduced into Russian airforce until very recent. K-77M might change that though.

The C-7 and D fly farther than the C-5 on the same motor which means..... it is lofting higher and getting a faster top speed as a result of the thinner air before burnout.

I wonder what so hard about lofting that require a whole new version to have more optimum angle.
Could the improvement in range came from better lead intercept logic?

[garrya]

DON'T USE DCS to test/model Air-to-Air missiles in DCS!
While DCS has many excellent points as a sim, the Air-to-Air missiles in this simulator, specially and namely the AMRAAM is pure crap is all and every possible way

Can you elaborate why do you think their missiles models are crap?
IMHO, because we have data chart from NASA test we can assess the accuracy of DCS model when Spurt put them in the same condition.

[sprstdlyscottsmn]

DON'T USE DCS to test/model Air-to-Air missiles in DCS!
While DCS has many excellent points as a sim, the Air-to-Air missiles in this simulator, specially and namely the AMRAAM is pure crap is all and every possible way

Can you elaborate why do you think their missiles models are crap?

Well, I can attest that you can fire 4 missiles in rapid succession at 4 targets in a formation and you will get at least 3 unique flight paths in DCS. One missile may loft, one wont, one to just randomly go wherever it wants, things like that.