Hellfire is available as two variants, one utilises laser designation while the second uses an RF based system. Brimstone however improves significantly upon both of these by incorporating a new MilliMetre Wave Radar (or MMWR) active seeker. The resolution offered by such a seeker provides Brimstone with ability to image targets. In addition the weapon can be pre-programmed with targetting and engagement information (assuming the aircraft has appropriate support) Combined these give Brimstone the ability to not only be specifically targeted but also to self-designate (and utilise appropriate engagement tactics) as required.

While Hellfire is launched from relatively slow moving platforms (helicopters), Brimstone must be capable of being launched and carried on fast moving platforms. To this end a new rail launch system has been developed by Flight Refuelling Ltd. (under contract to Alenia-Marconi) enabling safe carriage and release of the weapon by fixed wing aircraft. The launch assembly incorporates three individual rails thus allowing a significant number of weapons to be carried by a single aircraft (up to eighteen by a Eurofighter for example). Each weapon can be individually targeted and released by the launch aircraft. The system can be fitted with either a unitary or tandem warhead to counter reactive armour, detonation occurs upon impact.

Brimstone features a number of possible engagement profiles split between two modes, direct and indirect. If direct acquisition is possible the missile can be fired at that specific target. If several targets are to be attacked the missiles can be fired in salvo with each weapon taking either a common or dispersed path (depending on the positions of the targets). If a greater stand-off range is desired Brimstone can be launched at distance toward a target area. Both a minimum and maximum engagement range can be set to avoid friendly troops or collateral damage. Once over the area the missile can circle while its seeker tries to locate a target that matches one stored in its memory, the MMWR providing high resolution imagery. With a target aquired an appropriate impact point is selected and the missile dives toward it, exploding on impact. In both direct and indirect modes Brimstone utilises a common launch profile with the solid rocket boosting the missile to a supersonic velocity before burn out. After which the missile dives to a low altitude and coasts to the target using the MMWR as a terrain mapping radar.

In August 1999 Brimstone was sucessfully fired from a ground based launch system at the Yuma proving grounds in Arizona, USA. The first flight of Brimstone occurred on the 17th December 1998 aboard a DERA Tornado operating from BAes Warton site. The aircraft was fitted with twelve weapons (four units of three missiles) which will comprise a typical load in combat scenarios. By the middle of 1999 several flights had taken place including the first release of a missile in August 1999. In December 1999 a second sucessfull surface launched test firing of the missile occured in Arizona aimed at examining the navigation and seeker electronics.

經過一年多的評比後，GEC／Boeing合研的Brimstone反裝甲飛彈於1996年11月正式勝出，獲得總價超過十億英磅的研發量產合約．

長1.8公尺，寬0.3公尺，單發重量50公斤的Brimstone導彈源自地獄火式ATGM的大幅改善版，其以慣導與資料鏈進行中途導引，高解析度毫米波影像雷達尋標器作為終端導引，具有射後不理，多目標同時攻擊，迂迴飛行路徑，影像識敵（故不易被干擾誘騙）以及超音速頂攻等頂尖反裝甲性能特色；其最大有效射程據說可高達32公里，是老美為老英空軍之需求專門量身訂作的絕世武器，將配備於皇家空軍各式現役與未來打擊戰機之上；以歐洲颱風戰機為例，每架颱風一次最多可以新型三聯裝掛架同時攜帶18枚硫磺反戰車飛彈，並能同步攻向20~30公里外，18個不同裝甲目標；對於當今世上任何國家的裝甲部隊而言，這種場景只怕都會是其最深沉的恐懼與夢魘．．．．．．．．

1. Launch Modes

Indirect Mode is used when the targets are known and are out of sight of the attacking aircraft. The attack will usually have been planned in advance. If the aircraft has a databus between the cockpit and the weapons pylon, the aircrew can carry out mission planning or amendments en route to the release point. The engagement is set up so that the aircraft releases BRIMSTONE from a safe position, ensuring aircraft and aircrew survivability. The missile can be fired off boresight to facilitate use of terrain masking.

Direct Mode is where the pilot usually visually selects the target prior to weapon release, which may be assisted by an on-board sighting system. This mode is primarily intended for targets of opportunity or for self-defence against suddenly uncovered targets.

In both modes, BRIMSTONE supports off bore sight operation so the aircraft does not have to carry out any special manoeuvre prior to launch.

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2. Guidance:

BRIMSTONE’s millimetric wave (mmW) radar seeker is able to operate in all-weathers and throughout the 24 hour day. It is also not susceptible to battlefield obscurants such as smoke, dust, flares or chaff. A second function of the seeker is to give Brimstone a terrain avoidance capability, allowing it to cruise at a fixed height above the ground. It can be launched from ultra-low to high altitudes, allowing the pilot to select the launch altitude that avoids the possibility of successful attack from SAM systems. When launched from medium or high altitude, BRIMSTONE goes into a steep dive until it detects the ground below. The missile then pulls out to the cruise height.

Mid-course guidance is controlled by a digital autopilot and a highly accurate digital inertial measurement unit, giving the necessary high performance navigation required to locate the targets at long range and off-boresight operations.

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3. Salvo Firing:

When the target is a group or array of armoured vehicles, a broad attack front is required to engage the maximum number of vehicles. In such cases, multiple BRIMSTONE missiles can be fired in salvo, up to the entire platform load.

The missiles fly on separate paths that are spread out to cover the largest area.

Alternatively, missiles can be flown down the same corridor for the attack of in-line formations. A variety of engagement algorithms are used to eliminate the probability of hitting the same target more than once. For example, individual missiles can be commanded to hit sequentially numbered valid targets according to information passed from the aircraft before launch.

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4. Target Engagement:

During the search phase of the engagement, BRIMSTONE’s mmW seeker performs a comprehensive sweep on the ground directly ahead and to each side, searching for targets in its path. The advance mmW seeker constantly monitors the received radar signal, comparing it o aknown target signature in its memory.

It automatically rejects returns which do match (ie cars, buses, buildings) and continues searching and comparing until it identifies a valid target.

The missiles can be programmed not to search for targets until they reach a given point, allowing them to safely overfly friendly forces. They can also be programmed to stop searching beyond the safe engagement area or to only accept a target in a restricted box area. This provides collateral damage control.

The BRIMSTONE seeker operates in the high mmW band providing a high-resolution radar return image of the target, allowing real time target recognition and classification using on-board algorithms.

Once identified, BRIMSTONE scans the target to optimise its aimpoint and to maximise its lethality.

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5. Lethality:

BRIMSTONE emits a low power signal as it searches the ground just ahead of itself. Should the armoured target have a Defensive Aid Suite it will have little opportunity for successful deployment of countermeasures against the supersonic missile.

The BRIMSTONE warhead is a tandem shaped charge High-Explosive Anti-Tank (HEAT) warhead. The front charge initiates any reactive armour on the Main Battle Tank and clears the path for the main charge. The warhead is capable of defeating all known and projected armoured threats.

首先是CMM，原本CMM是為了掃盡天下美圖...嗯...應該是取代所有陸基TOW飛彈兼空中發射地獄火而發展的，但現在已經確定轉向空載地獄火的市場。這使得飛彈的彈徑從接近TOW的15.25公分成長到17.8公分，而彈重也接近49公斤。CMM將具有16公里的射程，並可被直昇機、固定翼機與無人飛機發射。可能發射的地上載具為美國的FCS或英國的FRES輪型裝甲車計畫。CMM將具有MMW/IIR/SAL的三重導引，外加資料鍵。

因應CMM的轉向，美國陸軍重新注重TOW的後續改良，將把現今TOW 2B提升到4.5km射程的ER型。另外還有資料鍵的射後不理F&F;計畫，以及可打穿60公分洞的反工事型。反工事型可能裝備在SBCT的裝甲車上，作為其突擊砲MGS服役前的替代品。

Boeing and Northrop Team On Common Modular Missile

因為防守方的射程延長，攻擊方的射程也必須加長。而當年的IIR記憶導引方式跟同時期的長弓MMW比較起來，是比較保守但較便宜的設計，然而當時的資料鍵快速演化成戰術網路，固態電子科技快速取代舊型雷達，從更遠的距離標定目標已經成為可能，連長弓MMW都已經有點落伍，就更別提Trigat了。

嗯，這應該冷戰後預算減少的關係。我記得原本計劃是現在就要服役，前一兩年德國國會還為了TRIGAT LR不能服役，撥款又買了一批HOT

>以色列比較晚起步，所以它不用花那麼多的研究經費

most likely because of different launch condition.
8~9 km from land
12~16km with sub-sonic jets
32km super-sonic jets from high altitude?