Patch 1.13 Requested Features/Fixes List (*Merged)

[EvilBivol-1]

- Idea how to fix the aim-120 a little bit -

 

 

some minutes ago, i fired a missile in lock on 1.02.

 

Maximal speed (fired from f-15, 500 kmh fast, 2000m high)

1.02 - Aim-120: ~ 3330 kmh

1.12 - Aim-120: ~ 3030 kmh

 

( in 1.02 the amraam is equal to the R-77 )

as you can see: the missile is 300 kmh faster (and burns longer!!)

 

Is there a way to replace the newer '120 with the older one?

-> not the shape, i mean the speed(file) etc

This is misleading - you should also check the drag numbers, which are lower for the AIM-120 in 1.12, so it slows down slower.

[RvEYoda]

Let us not talk about Lo 120 drag pls. This is one discussion I think

we should not defend ;). If you drop Lo missiles from the sky straight down

they are about as aerodynamic as a free falling person :P, at high altitude it

is the opposite (Lo missiles straight up : faster than going straight down).

[EvilBivol-1]

You have better AIM-120 drag numbers you could produce from a source?

[GGTharos]

He sure doesn't, but he's talking about a powered dive and climb I believe.

[RvEYoda]

It is quite logical to assume that the drag numbers of a missiles diving straight should be

better than falling human ;). Me i usually pick 8 human cannonballs in HL servers.

Another example could be that my plane goes Mach 2.2-2.4 without missiles and about

mach 1.2-1.4 with missiles loaded. (F-15 example, russian planes have it worse).

Maybe this is realistic (yes this is a sincere question).

 

ET/ER have it even worse. They're like putting up a big wall in front saying STOOOOOOP.

 

 

GG: Yes, for the up v down comparison. I have a vid of it if you would like to see.

 

GG i also believe you have some pretty good software for drag calculations?

[Pilotasso]

On another note, the Su-33 always flies like a bus, and with all its 10 missiles onboard, it fails to be aerobatic. Same thing for mig albeit it can supercruise and outrun every other plane in the game.

[EvilBivol-1]

It is quite logical to assume that the drag numbers of a missiles diving straight should be

better than falling human ;). Me i usually pick 8 human cannonballs in HL servers.

Another example could be that my plane goes Mach 2.2-2.4 without missiles and about

mach 1.2-1.4 with missiles loaded. (F-15 example, russian planes have it worse).

Maybe this is realistic (yes this is a sincere question).

I am not defending the modeling. Personally, I don't know what is and isn't realistic anyway. However, if you're going to compare AMRAAM performance changes between patches, especially the speed reduction, you need to look at the reduced drag index as well to get an accurate result. Otherwise, it is misleading and inaccurate.

 

As far as the drag index added to the aircraft SFM when missiles are loaded - I think it was settled that it is too large. I don't think this is the same drag index that is used for the missile's own FM though.

[GGTharos]

I don't need to see a vid, but I can tell you this ... an un-powered, mach 8 missile will hit the brakes below 200k feet, even coming straight down ... impact at mach 3. Although we don't know the terminal velosity of the AMRAAM, a powered dive should be unalikely to decelerate. We do, however, all know and love LO's scripted missile FM so I'm not going to argue this further. It is how it is. I'd guess the problem is in the lack of AoA calculations during maneuver, where going *up* means you have this drag from fins trying to do things and providing lift, and going down you have much less drag from the same, where you could fly at 0 AoA if you really wanted.

[GGTharos]

EB is correct. The 'drag on pylons' isn't the same as actualy missile drag in the missile FM. ED is looking at it. The F-15 should be getting up to some m1.8 with a full missile payload.

[RvEYoda]

EB is correct. The 'drag on pylons' isn't the same as actualy missile drag in the missile FM. ED is looking at it. The F-15 should be getting up to some m1.8 with a full missile payload.

 

Rgr,

 

However you say AoA dont affect missiles slowdown in Lo.

 

I tried this and found that at least turning increases the slowdown.

So the drag is somewhat dependent in Lo of how the missile turns, even if it

is not much. (tried horizontal only)

 

My Guess about terminal velocity of amraam is around somewhere around or above

M0.9-M1.2. Can't you minizap out an estimate like you did before, so we have an idea

of what we should be looking at :)

 

Edit : You were talking about 0g loft vs straight momentary path with same direction?

[Red Hammer]

May I ask what does ED dicide to do in the v1.13 so far?

[Pilotasso]

ED doesnt even know if the patch will be made.

[Geier]

Interesting read about AMRAAM.

 

 

 

Raytheon (Hughes) AIM-120 AMRAAM

 

The AIM-120 AMRAAM (Advanced Medium-Range Air-to-Air Missile) is a fire-and-forget air-to-air missile, and has replaced the AIM-7 Sparrow as the U.S. military's standard BVR (Beyond Visual Range) intercept missile.

In the late 1970s, the U.S. military services decided that they needed a medium-range air-to-air missile with a true fire-and-forget capability. The SARH (Semi-Active Radar Homing) guidance of the AIM-7 Sparrow required the launching aircraft's radar to illuminate the target until impact, which made the aircraft a target itself and also limited its ability to engage several targets simultaneously. In February 1979, Hughes and Raytheon were selected as finalists for the YAIM-120A AMRAAM (Advanced Medium-Range Air-to-Air Missile) competition, and in December 1981 Hughes was declared winner. A year before, a joint U.S./European agreement for development of a new family of air-to-air weapons had been signed. This agreement put the responsibility for the BVR AMRAAM to the United States, while the complementary ASRAAM (Advanced Short-Range Air-to-Air Missile) (later AIM-132) would be developed in Europe. In February 1984 the first production-representative AIM-120A missile was launched from an F-16 aircraft, but it was not before September 1987 that the first supersonic launch succeeded. The AMRAAM program was troubled by all sorts of technical and political problems, not the least of which was severe cost overrun because of the protracted development period. The first LRIP (Low-Rate Initial Production) AIM-120A was delivered in October 1988, but it took until September 1991 that IOC (Initial Operational Capability) was finally achieved.

 

The AIM-120A is powered by a solid-propellant rocket motor in a WPU-6/B propulsion section. Before launch, the launching aircraft's fire control system programs the missile's inertial autopilot in the WGU-16/B guidance unit to bring it into a homing basket in the vicinity of the target. The autopilot can receive mid-course updates from the aircraft via a data link. The AMRAAM's WCU-11/B control section controls the missile in flight with the four movable tail fins. As soon as the target is within range, the AMRAAM activates its active radar seeker for autonomous terminal homing. The 23 kg (50 lb) WDU-33/B fragmentation warhead is detonated by an FZU-49/B fuzing system consisting of a "smart" (anti-clutter) proximity fuze and an impact fuze. The effective range of the AIM-120A of course highly depends on the firing parameters, and official performance data are classified. Typical quoted figures for maximum range vary between 50 km (30 miles) and 70 km (45 miles). For the lower portions of the AMRAAM's range envelope (minimum range is said to be 2 km (2200 yds)), where the mid-course guidance updates are not needed, the AIM-120 is a true fire-and-forget weapon.

Non-tactical variants of the AIM-120A are the CATM-120A captive-carry training missile, the DATM-120A for ground-handling training, and the JAIM-120A with telemetry electronics for test and evaluation purposes.

Although a few AIM-120As were deployed to the Gulf during Operation Desert Storm in early 1991, no AMRAAMs were fired in that conflict (officially, at least). The first combat use of an AIM-120A occurred in December 1992, when an F-16C shot down an Iraqi MiG-25 during Operation Southern Watch.

The AIM-120B, which was first delivered in late 1994, had a new WGU-41/B guidance section. It had software in reprogrammable EPROM modules, a new digital processor and other electronics updates. Non-tactical versions are the CATM-120B captive-carry and JAIM-120B test and evaluation missiles.

[Geier]

The AMRAAM P3I (Pre-Planned Product Improvement) program led to the AIM-120C, first delivered in 1996. The major new feature of the basic AIM-120C (P3I Phase 1) are the clipped wings and fins. Although this feature was introduced to allow carriage in the internal weapons bays of the F/A-22 Raptor, the -120C can also be used from other AMRAAM-capable aircraft. The guidance unit of the AIM-120C is upgraded to WGU-44/B standard. The first P3I Phase 2 missile is the AIM-120C-4 (first delivered in 1999), which has an improved WDU-41/B warhead. The AIM-120C-5 is a C-4 with a slightly larger motor in the new WPU-16/B propulsion section and a new shorter WCU-28/B control section with compressed electronics and ECCM upgrades. Deliveries of the AIM-120C-5 began in July 2000. It was followed on the production line by the AIM-120C-6, which features an updated TDD (Target Detection Device). The AIM-120C-7 (P3I Phase 3), development of which has begun in 1998, incorporates improved ECCM with jamming detection, an upgraded seeker, and longer range. The latter feature was specifically requested by the U.S. Navy to get a (somewhat) suitable replacement for the AIM-54 Phoenix very-long range missile, which was then planned to be retired together with the F-14D Tomcat around 2007 (actual official retirement was already in September 2004). The AIM-120C-7 was successfully tested against combat-realistic targets in August and September 2003, and IOC was then planned for 2004. This has slipped somewhat, but as of early 2006, the AIM-120C-7 is beginning to be fielded. Equivalent to the -120A/B, there are also CATM-120C and JAIM-120C non-tactical variants of the AIM-120C.

 

The AIM-120D (P3I Phase 4, formerly known as AIM-120C-8) is a development of the AIM-120C with a two-way data link, more accurate navigation using a GPS-enhanced IMU, an expanded no-escape envelope, improved HOBS (High-Angle Off-Boresight) capability, and a 50% increase in range. The AIM-120D is a joint USAF/USN project, and is currently in the testing phase. First production deliveries are expected for December 2007. The CATM-120D is the inert captive-carry training version of the AIM-120D.

More than 12000 AIM-120 missiles of all versions have been built so far, including a significant amount for non-U.S. customers. The AMRAAM can be carried by all current U.S. fighter aircraft (F-14D, F-15, F-16, F/A-18, F/A-22), and is launched from LAU-127/A, -128/A or -129/A CRLs (Common Rail Launchers), which can also be used for the AIM-9 Sidewinder.

NCADE

 

NCADE (Network Centric Airborne Defense Element) is a program to develop an air-launched anti-missile interceptor missile using AMRAAM components. The NCADE missile replaces the AIM-120's radar seeker with the IIR (Imaging Infrared) seeker of the AIM-9X Sidewinder, and changes the propulsion system to a two-stage rocket. The latter consists of an AIM-120 first stage and a new Aerojet second stage, which can provide a thrust of 0.55 kN (125 lb) for more than 25 seconds. NCADE's airframe, flight control system and aircraft interface are essentially the same as on the AIM-120, making the missile immediately compatible with many existing launch platforms.

The NCADE missile is intended to intercept short- to medium-range ballistic missiles in the boost, ascent, or terminal phase. To achieve this, the missile is fired upwards by the first-stage motor in a very steep angle. At high altitude, the IIR seeker can acquire a target, and then the missile will use its long burning second-stage motor for the intercept.

At the time of this writing, the NCADE program is undergoing component tests (propulsion and seeker). No planned timeframe for a test of an all-up NCADE round has been announced so far.

Ground-Launched AMRAAM

 

The AIM-120 missile is also used in some ground-launched applications. Norway uses the NASAMS (Norwegian Advanced Surface-to-Air Missile System), which employs the AMRAAM missile from a six-round box launcher. NASAMS became operational in 1995. Although the designation MIM-120A is sometimes quoted for the missiles, this is not an official DOD designation.

 

Beginning in 1995, the U.S. Army evaluated the use of AMRAAM from modified Hawk launchers and from HMMWV (High-Mobility Multipurpose Wheeled Vehicle) in a system known as HUMRAAM ("Hummer-AMRAAM"). The U.S. Marine Corps version of HUMRAAM is known as CLAWS (Complimentary Low-Altitude Weapon System), and in April 2001 Raytheon received a development and pre-production contract for CLAWS, which is intended to replace the USMC's retired MIM-23 Hawk system from 2006/2007.

 

Current U.S. Army plans for a ground-based AMRAAM system are called SLAMRAAM (Surface-Launched AMRAAM). The SLAMRAAM system is also based on HMMWV vehicles, and is planned to become operational in 2008. It will replace some of the Army's Avenger air-defense systems, which use the smaller and less capable FIM-92 Stinger missile. CLAWS and SLAMRAAM are planned to use a common launch system by the end of the decade.

[Geier]

Specifications

 

Note: Data given by several sources show slight variations. Figures given below may therefore be inaccurate! Especially the range figures are rough estimates only.

Data for

AIM-120A/B/C: AIM-120A/B AIM-120C-5

Length 3.66 m (12 ft)

Wingspan 53.3 cm (21 in) 44.7 cm (17.6 in)

Finspan 63.5 cm (25 in) 44.7 cm (17.6 in)

Diameter 17.8 cm (7 in)

Weight 157 kg (345 lb)

Speed Mach 4

Range 50-70 km (30-45 miles) > 105 km (65 miles)

Propulsion Hercules/Aerojet solid-fueled rocket

Warhead

23 kg (50 lb) WDU-33/B blast-fragmentation 18 kg (40 lb) WDU-41/B blast-fragmentation

 

http://www.designation-systems.net/dusrm/m-120.html

[Eagle Driver]

... and a 50% increase in range.

 

That's the big one for me. That is a huge increase and will really increase the lethality of this already stellar missile system [cough].

[tflash]

This is misleading - you should also check the drag numbers, which are lower for the AIM-120 in 1.12, so it slows down slower.

 

Sorry EB, I for my part don't buy this. I have both Lomac and Lo:FC on the same system, and I'm 100% confident that the speed difference is what has broken the Amraam.

[yar]

yeah! the aim-120 in 1.02 is realy better than in 1.12.

 

if you fire both missiles (R-77 and aim-120) you will see the big difference!

[EvilBivol-1]

Sorry EB, I for my part don't buy this. I have both Lomac and Lo:FC on the same system, and I'm 100% confident that the speed difference is what has broken the Amraam.

There is nothing to buy. I'm not trying to convince you of anything. It's just a fact - the AIM-120's top speed and drag index were lowered in FC (not sure which patch anymore). However, most observers, including yar above, only note the first part, not the second. So I'm here to highlight the second, so that when you take measurements, they turn out more accurate.

[yar]

what helps a accurate turnrate, if they have no speed left? If a bandit make a turn, the amraam may turn very well, but it has no speed -> missile gone!

 

 

PS. can you allocate your opinion with examples from lock on? (maybe tacview file or something else)

 

 

 

My conclusion:

 

a missile with a lowered drad index and speed is realy useless!

[tflash]

My suggestion is simple: just raise the initial speed of the Amraam, and a lot of the problems will disappear. No recoding necessary.

 

The very strange reasoning for lowering the speed is that they did not find published indications for a higher speed. This is not a good argument, since essentially the speed is *classified*, so what Ed has implemented are just *claims*, not facts. For the overall balance of the game a *very easy fix* is just to make the data for Amraam and R-77 more equal. It makes no sense to have the so-called realistic parameters if the result becomes so unreal as it is now.

The parameters just seem to have an undesired impact in Lockon, one they sure don't have in reality, given the Amraam's kill tally.

 

Fact is that lower speed + less drag in Lockon = broken missile

[yar]

i only can assent to your post tflash!

[EvilBivol-1]

/taps microphone

 

... hello? Is this thing on? One-two; one-two-three...

 

/tap tap

 

Guys - relax please. I'm not trying to argue with you. I'm not defending the "realism" of the model. I too would like to see ED take another look at the missile issues and have requested so, as has GGTharos, DScythe and a whole lot of many other people.

 

But - if you're going to try and make a numerical comparison - like yar did above - you should take care to notice not only the lower speed, but also the fact that the missile slows down slower, which means it might have more speed when it reaches the target. Just a matter of accurate assessment.

[yar]

but also the fact that the missile slows down slower, which means it might have more speed when it reaches the target.

im not shure if they slow down slower.

 

i wanted to analyse this, but my tacview (0.91) didn't record the 1.02 flight :-/

so i cant say if the missile slow down faster/slower...

[EvilBivol-1]

Sorry, I'm actually comparing 1.1 with 1.12a. I haven't checked 1.02.