The following article was published on the April 1990 edition of Aviatsia i Kosmomavtika, the service journal of the Soviet Air Force. It deals with the use of the precission guided munitions on poor weather and night, while it doesn't mentions /explicitely/ the Su-24M and MiG-27K/Su-17M4, from the description is pretty obvious..
"Combat Training: Viewpoints, Suggestions," by Military Pilot 1st Class Col V. Bragin, candidate of military sciences, docent: "In More Complex Conditions"]
Modern bombers, fighter-bombers, and ground-attack aircraft are armed with guided weapons in various modifications, with laser and TV seekers, and particu¬larly guided missiles and "smart" bombs. When these weapons are used, strike aircraft have considerably greater capabilities to destroy enemy targets.
The experience of local wars and armed conflicts indi¬cates, however, that guided weapons of this category have been employed for the most part during daylight in VFR conditions, extremely rarely at night with target illumination, and they have been employed practically not at all in conditions of limited visibility. In the two latter instances this has been due to difficulty in visual target search and tracking with the laser and TV target engagement system's video monitoring device, as well as very frequently the impossibility of strike delivery due to target detection after passing the "smart" bomb release point or missile launch point. For this reason the search for tactics and modes of actions involving the employ¬ment of guided weapons in conditions of limited visi¬bility and poor light conditions constitutes an urgent problem for frontal aviation strike aircraft.
Combined employment by aircrews of targeting radar (RPO), sighting optics (PPV), and laser and TV weapon sights can be considered one focal area in the develop¬ment of tactics, while combined operations by aircraft elements of different types can be considered a focal area in development of modes of actions. The former pre¬sumes that when aiming, the RPO, PPV, and LTPS crosshair reticles are placed on the same point. Superim-position error should not exceed 4 minutes of angle. Then, after "referencing" with the RPO or PPV and switching on the optical laser (OKG), the laser beam is directed to the target and the LTPS will "illuminate" it, following the target with sighting reticle and operating either in "program-corrected" tracking (PKS) or auto¬matic correction tracking (AKS) mode. This enables the crew to effect guided weapon launch (release) with target engagement by RPO (PPV) until the target is detected with the LTPS, or without a target image on the VKU display with an inadequate light level.
Employment of guided weapons with target engagement by RPO is possible if the aircraft remains within the target engagement system search sector right up to guid¬ance termination. Analysis of RPO and LTPS zones of visibility and areas of possible missile launch and guided bomb release (see Figure 1 in following article) indicates that missile guidance and launch is not assured at low altitudes and at close range. Optimal conditions are range in excess of 5.5 km and altitude from 200 to 1,500 meters. "Smart" bomb guidance, however, is performed throughout the range of release heights. The seeker should lock on the laser spot no later than 10-11 seconds before burst.
Tactics have been devised in conformity with the above-stated possibilities of combined employment of targeting and target engagement systems, for delivery of strikes by frontal-aviation bombers delivering "smart" bombs, when the target is detected with the LTPS following bomb release using the RPO. When striking an airfield, for example, when the strike aircraft approaches to a distance of 20-25 km, it climbs to bomb release height, aims to the runway (or to an aiming-off point) by radar, releases the bomb and simultaneously switches on the optical laser (see Figure 2 in following article). The LTPS operates in PKS or AKS mode. When the target appears on the VKU, the systems operator, with the MUP [expansion unknown], places the crosshair reticle on the target and holds it there, continuing bomb guidance right up to the moment of burst.
If strike target light level and contrast are insufficient for detection with the LTPS, particularly at night, the bomber crew can employ missiles with laser seeker, aiming only with RPO (see Figure 3 in following article). In this case missiles are launched from a shallow dive at long range and from a height of 2,500-3,000 meters, with LTPS switched on. The RPO crosshair reticle is held precisely on the target until detonation, while guidance is by optical laser, but with an accuracy determined by aiming system alignment error.
Guided bombs, however, cannot be employed in these conditions or when released from within or above clouds from a single aircraft, since at a certain moment the target leaves the RPO field of view, and LTPS target tracking breaks. Illumination of the target with an optical laser carried by another aircraft is a solution to the problem, however (see AVIATSIYA I KOSMONAVTIKA, No 2, 1990). The other aircraft should reach the laser switch-on point 10-11 seconds before bomb deto¬nation.
With this strike delivery variation, the lead aircraft drops the guided bomb, while the wingman illuminates the target. Both aircraft employ radar aiming. In order to reach the optical-laser switch-on point at the proper time, the wingman follows behind the leader at a dis¬tance of deltaD, holding this distance using the RSBN-6S [local radio navigation system] in intercept mode. The distance is calculated as follows: deltaD=VwiTgb+Drmin-A+2sd rsbn, where Vwi—airspeed of wingman; Tgb and A—guided bomb time of fall and carry; Drmin— minimum range at which target is visible to wingman in radar bombsight (Np+1 km); sd rsbn—error in main¬taining distance between aircraft with RSBN-6S.
The wingman should proceed on final target heading under cloud cover. Cloud bases should not be below 800-900 meters in order to ensure bomb guidance in the terminal phase, during the last 10-11 seconds before burst.
Fighter-bombers and ground-attack aircraft which are not equipped with radar target engagement systems employ guided weapons at night principally on illumi¬nated targets. Figuring that intensity of illumination should be not less than 2,000 lux, even with visibility of 10 km and more it will be necessary to drop up to 30-50 illumination flares. They form a masking background, however, in conditions of obscuring dust and smoke, making visual detection of the target difficult and at times impossible.
Capabilities to employ guided weapons are significantly enhanced if they carry a passive TV correlation seeker. Under these conditions guided bombs can be employed with a terrain illumination level of not less than 40-50 lux. This level is present at dusk, while during hours of darkness sufficient intensity of illumination can be pro¬duced with from 10 to 12 parachute flares (with visibility (meteorological) of 10 km), which will require two or three illumination aircraft. Targets marked in advance with aircraft-dropped parachute signal flares can also be hit with guided bombs with a correlation-type seeker. For this it will be necessary to establish in the target area a cluster consisting of at least three points of illumina¬tion, taking into consideration the specific operating features of the guidance system.
If the level of illumination at dusk and at night is sufficient or if the target is illuminated, one can employ guided missiles with laser seeker against it, with an optical target engagement system. Following visual detection of the target, the pilot places the crosshair reticle on it and "references the target"; he then keeps the aiming mark on it. When the optical laser is switched on, the laser beam will illuminate the target and guide the missile, but with an error determined by optical sight and LTPS adjustment accuracy. A strike using this method will require an illumination aircraft and a strike aircraft at night, and strike aircraft alone at dusk.
Employment of guided weapons by aircraft from dif¬ferent frontal-aviation components is also possible in combined missions. Bombers equipped with the most accurate integrated targeting and navigation system should fly as mission leaders for the other strike ele¬ments, marking or illuminating specified targets with RPO target engagement, as well as providing guided weapons guidance with LTPS. The fighter-bombers and ground-attack aircraft will release (launch) their guided weapons at the leaders' command at an illuminated or marked target. Depending on the situation, bombers can function both as leaders and can concomitantly carry out their primary mission.
Figure 4 (see following article) shows a variation of strike on an enemy airfield by multiple-component forces. The bomber elements are headed for assigned targets located at operational depth, but they are routed across the fighter-bombers' target. All elements in a common for¬mation maintain visual contact and are escorted by jammer aircraft and fighters. Upon approaching the target airfield, the bomber flight climbs to 3,000 meters and opens up to lateral spacings of 600-800 meters. The fighter-bombers attach to their leaders in pairs. The bomber-leaders place their radar aiming point on the runway and give the command to the other aircraft to release their guided bombs. After this the fighter-bombers descend to low level and return to base, while the bombers continue on to their target area.
The second flight of bombers, trailing the first flight by distance deltaD, maintained by RSBN-6S or visually, also place their radar aiming point on the runway and, with switched-on optical laser, guide the bombs released by the fighter-bombers. Four target damage areas form on the runway, and the airfield is knocked out of operation. At the moment of bomb burst the bombers break from the target and proceed to their own targets. This procedure of delivering a strike by multiple-component forces makes it possible for fighter-bombers to employ guided weapons with limited visibility and illumination. In addition, the force of supporting aircraft is reduced, and when elements fly in a common forma¬tion, favorable conditions are ensured for air defense penetration.
Depending on range of launch (release), probable error can increase by a factor of 1.5 to 2 in comparison with standard errors for an LTPS. In any case, however, they remain smaller by a factor of 5 to 10 than in the case of unguided weapons. Nevertheless all sighting systems should be aligned as accurately as possible.
In order to confirm the above, calculations were made to determine the required forces to destroy a river crossing facility in a night strike. Frontal-aviation bombers employ guided missiles (LTPS, RPO, and LTPS target engagement) or high explosive fragmentation bombs (RPO aiming), while the fighter-bombers drop bombs (optical bombsight aiming only).
Based on results, effectiveness of strike aircraft actions with guided weapons delivery and combined employ¬ment of sighting systems proves to be half that when direct LTPS target engagement is employed, but effec¬tiveness is five to nine times that achieved with gravity bombs. It is therefore advisable to test the proposed tactics and modes of frontal-aviation actions during limited visibility and at night by means of an in-air experiment, to refine and detail the manner and proce¬dure of execution, and extensively to adopt these tactics in the practical combat training of Air Force line units.
Figure 1. Boundaries of Zones of Visibility With RPO and LTPS, Guided Missile Launch Range and Guided Bomb
Release Range Envelopes.
Key: 1. Boundary of aircraft location at moment of guided bomb detonation 2. Commencement of guidance 3. From LTPS 4. Boundary of zone of visibility with RPO 5. Guided bomb carry path, no-wind conditions 6. Guided bomb release range envelope 7. Guided missile launch range envelope 8. Required for guided bomb release with LTPS 9. LTPS switch-on point for guided missile.
Hope you enjoyed!
"Combat Training: Viewpoints, Suggestions," by Military Pilot 1st Class Col V. Bragin, candidate of military sciences, docent: "In More Complex Conditions"]
Modern bombers, fighter-bombers, and ground-attack aircraft are armed with guided weapons in various modifications, with laser and TV seekers, and particu¬larly guided missiles and "smart" bombs. When these weapons are used, strike aircraft have considerably greater capabilities to destroy enemy targets.
The experience of local wars and armed conflicts indi¬cates, however, that guided weapons of this category have been employed for the most part during daylight in VFR conditions, extremely rarely at night with target illumination, and they have been employed practically not at all in conditions of limited visibility. In the two latter instances this has been due to difficulty in visual target search and tracking with the laser and TV target engagement system's video monitoring device, as well as very frequently the impossibility of strike delivery due to target detection after passing the "smart" bomb release point or missile launch point. For this reason the search for tactics and modes of actions involving the employ¬ment of guided weapons in conditions of limited visi¬bility and poor light conditions constitutes an urgent problem for frontal aviation strike aircraft.
Combined employment by aircrews of targeting radar (RPO), sighting optics (PPV), and laser and TV weapon sights can be considered one focal area in the develop¬ment of tactics, while combined operations by aircraft elements of different types can be considered a focal area in development of modes of actions. The former pre¬sumes that when aiming, the RPO, PPV, and LTPS crosshair reticles are placed on the same point. Superim-position error should not exceed 4 minutes of angle. Then, after "referencing" with the RPO or PPV and switching on the optical laser (OKG), the laser beam is directed to the target and the LTPS will "illuminate" it, following the target with sighting reticle and operating either in "program-corrected" tracking (PKS) or auto¬matic correction tracking (AKS) mode. This enables the crew to effect guided weapon launch (release) with target engagement by RPO (PPV) until the target is detected with the LTPS, or without a target image on the VKU display with an inadequate light level.
Employment of guided weapons with target engagement by RPO is possible if the aircraft remains within the target engagement system search sector right up to guid¬ance termination. Analysis of RPO and LTPS zones of visibility and areas of possible missile launch and guided bomb release (see Figure 1 in following article) indicates that missile guidance and launch is not assured at low altitudes and at close range. Optimal conditions are range in excess of 5.5 km and altitude from 200 to 1,500 meters. "Smart" bomb guidance, however, is performed throughout the range of release heights. The seeker should lock on the laser spot no later than 10-11 seconds before burst.
Tactics have been devised in conformity with the above-stated possibilities of combined employment of targeting and target engagement systems, for delivery of strikes by frontal-aviation bombers delivering "smart" bombs, when the target is detected with the LTPS following bomb release using the RPO. When striking an airfield, for example, when the strike aircraft approaches to a distance of 20-25 km, it climbs to bomb release height, aims to the runway (or to an aiming-off point) by radar, releases the bomb and simultaneously switches on the optical laser (see Figure 2 in following article). The LTPS operates in PKS or AKS mode. When the target appears on the VKU, the systems operator, with the MUP [expansion unknown], places the crosshair reticle on the target and holds it there, continuing bomb guidance right up to the moment of burst.
If strike target light level and contrast are insufficient for detection with the LTPS, particularly at night, the bomber crew can employ missiles with laser seeker, aiming only with RPO (see Figure 3 in following article). In this case missiles are launched from a shallow dive at long range and from a height of 2,500-3,000 meters, with LTPS switched on. The RPO crosshair reticle is held precisely on the target until detonation, while guidance is by optical laser, but with an accuracy determined by aiming system alignment error.
Guided bombs, however, cannot be employed in these conditions or when released from within or above clouds from a single aircraft, since at a certain moment the target leaves the RPO field of view, and LTPS target tracking breaks. Illumination of the target with an optical laser carried by another aircraft is a solution to the problem, however (see AVIATSIYA I KOSMONAVTIKA, No 2, 1990). The other aircraft should reach the laser switch-on point 10-11 seconds before bomb deto¬nation.
With this strike delivery variation, the lead aircraft drops the guided bomb, while the wingman illuminates the target. Both aircraft employ radar aiming. In order to reach the optical-laser switch-on point at the proper time, the wingman follows behind the leader at a dis¬tance of deltaD, holding this distance using the RSBN-6S [local radio navigation system] in intercept mode. The distance is calculated as follows: deltaD=VwiTgb+Drmin-A+2sd rsbn, where Vwi—airspeed of wingman; Tgb and A—guided bomb time of fall and carry; Drmin— minimum range at which target is visible to wingman in radar bombsight (Np+1 km); sd rsbn—error in main¬taining distance between aircraft with RSBN-6S.
The wingman should proceed on final target heading under cloud cover. Cloud bases should not be below 800-900 meters in order to ensure bomb guidance in the terminal phase, during the last 10-11 seconds before burst.
Fighter-bombers and ground-attack aircraft which are not equipped with radar target engagement systems employ guided weapons at night principally on illumi¬nated targets. Figuring that intensity of illumination should be not less than 2,000 lux, even with visibility of 10 km and more it will be necessary to drop up to 30-50 illumination flares. They form a masking background, however, in conditions of obscuring dust and smoke, making visual detection of the target difficult and at times impossible.
Capabilities to employ guided weapons are significantly enhanced if they carry a passive TV correlation seeker. Under these conditions guided bombs can be employed with a terrain illumination level of not less than 40-50 lux. This level is present at dusk, while during hours of darkness sufficient intensity of illumination can be pro¬duced with from 10 to 12 parachute flares (with visibility (meteorological) of 10 km), which will require two or three illumination aircraft. Targets marked in advance with aircraft-dropped parachute signal flares can also be hit with guided bombs with a correlation-type seeker. For this it will be necessary to establish in the target area a cluster consisting of at least three points of illumina¬tion, taking into consideration the specific operating features of the guidance system.
If the level of illumination at dusk and at night is sufficient or if the target is illuminated, one can employ guided missiles with laser seeker against it, with an optical target engagement system. Following visual detection of the target, the pilot places the crosshair reticle on it and "references the target"; he then keeps the aiming mark on it. When the optical laser is switched on, the laser beam will illuminate the target and guide the missile, but with an error determined by optical sight and LTPS adjustment accuracy. A strike using this method will require an illumination aircraft and a strike aircraft at night, and strike aircraft alone at dusk.
Employment of guided weapons by aircraft from dif¬ferent frontal-aviation components is also possible in combined missions. Bombers equipped with the most accurate integrated targeting and navigation system should fly as mission leaders for the other strike ele¬ments, marking or illuminating specified targets with RPO target engagement, as well as providing guided weapons guidance with LTPS. The fighter-bombers and ground-attack aircraft will release (launch) their guided weapons at the leaders' command at an illuminated or marked target. Depending on the situation, bombers can function both as leaders and can concomitantly carry out their primary mission.
Figure 4 (see following article) shows a variation of strike on an enemy airfield by multiple-component forces. The bomber elements are headed for assigned targets located at operational depth, but they are routed across the fighter-bombers' target. All elements in a common for¬mation maintain visual contact and are escorted by jammer aircraft and fighters. Upon approaching the target airfield, the bomber flight climbs to 3,000 meters and opens up to lateral spacings of 600-800 meters. The fighter-bombers attach to their leaders in pairs. The bomber-leaders place their radar aiming point on the runway and give the command to the other aircraft to release their guided bombs. After this the fighter-bombers descend to low level and return to base, while the bombers continue on to their target area.
The second flight of bombers, trailing the first flight by distance deltaD, maintained by RSBN-6S or visually, also place their radar aiming point on the runway and, with switched-on optical laser, guide the bombs released by the fighter-bombers. Four target damage areas form on the runway, and the airfield is knocked out of operation. At the moment of bomb burst the bombers break from the target and proceed to their own targets. This procedure of delivering a strike by multiple-component forces makes it possible for fighter-bombers to employ guided weapons with limited visibility and illumination. In addition, the force of supporting aircraft is reduced, and when elements fly in a common forma¬tion, favorable conditions are ensured for air defense penetration.

Depending on range of launch (release), probable error can increase by a factor of 1.5 to 2 in comparison with standard errors for an LTPS. In any case, however, they remain smaller by a factor of 5 to 10 than in the case of unguided weapons. Nevertheless all sighting systems should be aligned as accurately as possible.
In order to confirm the above, calculations were made to determine the required forces to destroy a river crossing facility in a night strike. Frontal-aviation bombers employ guided missiles (LTPS, RPO, and LTPS target engagement) or high explosive fragmentation bombs (RPO aiming), while the fighter-bombers drop bombs (optical bombsight aiming only).
Based on results, effectiveness of strike aircraft actions with guided weapons delivery and combined employ¬ment of sighting systems proves to be half that when direct LTPS target engagement is employed, but effec¬tiveness is five to nine times that achieved with gravity bombs. It is therefore advisable to test the proposed tactics and modes of frontal-aviation actions during limited visibility and at night by means of an in-air experiment, to refine and detail the manner and proce¬dure of execution, and extensively to adopt these tactics in the practical combat training of Air Force line units.

Figure 1. Boundaries of Zones of Visibility With RPO and LTPS, Guided Missile Launch Range and Guided Bomb
Release Range Envelopes.
Key: 1. Boundary of aircraft location at moment of guided bomb detonation 2. Commencement of guidance 3. From LTPS 4. Boundary of zone of visibility with RPO 5. Guided bomb carry path, no-wind conditions 6. Guided bomb release range envelope 7. Guided missile launch range envelope 8. Required for guided bomb release with LTPS 9. LTPS switch-on point for guided missile.



Hope you enjoyed!