GUIDE: The advanced barrel roll or how to outmaneuver 27ERs

[Croncat]

So lets assume you have a SU27 at your 6 within 6NM and he is firering 27ERs at you. What to do?

 

The problem with many maneuvers is, that the bandit will close in the distance, and you risk to get a R73 in your face. So I developed a high 1G maneuver that I call atm advanced barrel roll.

 

The maneuver starts like a normal barrel roll, lets say you push your stick left and up. So you start like a normal barrel roll, pushing your stick left but instead of continuing you cancel the movement immediatly out. You do the same with the up movement. Rinse and repeat. Therefore the bandit can't close the distance.

 

Here a small video where you can see this in action.

 

 

I use *small* amounts of chaff, for some reason that is not visible in the video.

[Cik]

ah, i see. it's a jokepost.

 

took me awhile, very clever my friend.:thumbup:

[DarkFire]

He he good video! My current Pk with the R-27ER is something like 5%, with every missile launched at Rmax, well within parameters. That chaff susceptibility :mad:

[Ironhand]

...My current Pk with the R-27ER is something like 5%, with every missile launched at Rmax...

You sure about the Rmax part? 5% sound more like launches between Rtr and Rmin.

[*Rage*]

Choo choo!

 

Another stop in the ER miss-track fun train.

[DarkFire]

You sure about the Rmax part? 5% sound more like launches between Rtr and Rmin.

 

Ah, good catch. Yes, I meant to type Rmax 2, which would be Rtr or beneath.

[Sweep]

Choo choo!

 

Another stop in the ER miss-track fun train.

 

You may find this interesting, its an R-27R's take on the situation: http://imgur.com/njDmtK2

 

 

Edit: BTW/For the OP: Looks like that ran out of energy, I've had about zero luck defending a very low aspect, RTR AA-10C with or without CM employment.

 

I'm talking maybe defeating 3 out of ~10-12 launches in that scenario. (over the past 2 years)

 

Yeah yeah, I have no evidence of anything... :(

 

Edit 2: Hmmm...I may have deleted a line or two in my first edit...wth...Probably irrelevant anyway.

Edited March 10, 2016 by Sweep
Crappy anecdotal evidence is great, right?

[DarkFire]

You may find this interesting, its an R-27R's take on the situation: http://imgur.com/njDmtK2

 

 

Edit: BTW/For the OP: Looks like that ran out of energy, I've had about zero luck defending a very low aspect, RTR AA-10C with or without CM employment.

 

I'm talking maybe defeating 3 out of ~10-12 launches in that scenario. (over the past 2 years)

 

Yeah yeah, I have no evidence of anything... :(

 

Edit 2: Hmmm...I may have deleted a line or two in my first edit...wth...Probably irrelevant anyway.

 

Do you have any tacview recordings by any chance? I'm not saying you're wrong, rather I want to see what I might be doing wrong.

[winchesterdelta1]

I dont even shoot AIM-120C's on a high speed running target from around 6nm.

[SinusoidDelta]

I dont even shoot AIM-120C's on a high speed running target from around 6nm.

 

That's what I was thinking....especially when they're going Mach 1.2 on the deck.

[Nerd1000]

I dont even shoot AIM-120C's on a high speed running target from around 6nm.

The last shot was at 4.5 nm.

 

In any case, I think the OP's main point is that those missiles went dumb as soon as they left the rail.

[SinusoidDelta]

I have acmi's of sparrows doing far worse.

[Nerd1000]

I have acmi's of sparrows doing far worse.

What could be worse than going dumb straight off the rail? Did your missiles do a 180 degree turn and hit you?

[Croncat]

In any case, I think the OP's main point is that those missiles went dumb as soon as they left the rail.

 

I'm learning the F15 for a week now and try to figure out how to maneuver, and my main point is, that not maneuvering can be sometimes your best bet.

 

Can be successful, in the case of the video I flew behind some mountains and we lost track of each other.

 

On the other hand it doesn't work everytime, in the case of the video, after we've lost track of each other, I was bingo fuel and crashed.

[FeistyLemur]

Just wait for him to run out of 27er's when they all miss.

[Stuge]

There's a reason why these missiles don't track:

 

Matched speeds between chaser and runner.

 

Just try it. If you chase a target and match his speed, your radar will go dumb. Of course you gotta have some separation, like in the video. Works with F-15C and sparrow also. In the case of Su-27 you maintain lock thanks to your IRST. But the ER can't use that (not in game anyway).

 

I think there was a radar physics -related explanation, but I can't remember it. Maybe someone who knows may enlighten us?

[Bushmanni]

There's another "notch" or blind speed that causes the radar to lose lock besides notching which is zero closure. I haven't seen this phenomenon myself for ages but it was modeled at least in some point or it could be issue only in Su-27 (I fly mostly F-15). So it could simply be that the bandit kept losing lock on you as you both are flying pretty much at the same speed. Your speeds change due to maneuvers which enables the bandit to lock you again and fox another missile just to lose the lock right afterwards again.

 

 

2nd edit: What I wrote might be the correct explanation.

This blind speed is due to sidelobe clutter having it's peak amplitude just at the zero closure speed ie. clutter from the sidelobe pointed straight down. This sidelobe has shortest travel distance to ground and 90 degree angle to minimize scattering. This is an issue only at low altitude. Side lobe clutter is also reason why you cant see cold targets as far away as hot ones. Main lobe pointing straight forward has the highest doppler shift from ground echoes and all sidelobes have less doppler shift as they point more or less away from the flying direction, ie. the side lobe clutter has same frequencies as echoes from receding targets.

 

The reason I'm suspecting this theory is that I'm uncertain if this effect is as strong as is presented in DCS, ie. it should only reduce the detection distance against co-speed cold targets vs. cold targets flying at different speed, not make it pretty much impossible to keep lock on them even at close distances.

Edited March 12, 2016 by Bushmanni

[Stuge]

Thank you Bush!

 

It is modeled in the game. But I've seen it happen at higher altitudes also. The speed difference needs to be really small, something like within 50 km/h for this phenomenon to occur.

[Stuge]

I should add that this is the exact reason why sometimes the ER refuses to launch, despite being seemingly within launch parameters.

[GGTharos]

This was modeled with respect to the Flanker/MiG radar but is not at all correct for the APG-63.

 

There's another "notch" or blind speed that causes the radar to lose lock besides notching which is zero closure. I haven't seen this phenomenon myself for ages but it was modeled at least in some point or it could be issue only in Su-27 (I fly mostly F-15). So it could simply be that the bandit kept losing lock on you as you both are flying pretty much at the same speed. Your speeds change due to maneuvers which enables the bandit to lock you again and fox another missile just to lose the lock right afterwards again.

 

 

edit: What I wrote probably isn't correct explanation.

This blind speed is due to sidelobe clutter having it's peak amplitude just at the zero closure speed ie. clutter from the sidelobe pointed straight down. This is an issue only at low altitude. There could be other blind speeds depending on how the signal processing is designed and what radar mode is used but these are not modeled in DCS.

[Frostie]

Lock him up, slam on the brakes, fire, RTB for medals.

[SinusoidDelta]

What could be worse than going dumb straight off the rail? Did your missiles do a 180 degree turn and hit you?

Edited March 13, 2016 by SinusoidDelta

[Nerd1000]

<snip>

Crappy AIM-7 kinematics plus the SARH easy spoofing issue makes for some frustration, I guess. At least that missile tracked for a little while.

[EagleFox]

I got a lot easier way to dodge ERs. Just pop 2 chaffs XD

[ShuRugal]

http://i.imgur.com/bzVurPy.gif

 

I don't get it. The missile tracked. How is that worse than a missile that didn't track?