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Koliko samo verzija radara `Safir` je bilo ...
Citat:Sapfir-23 NATO "High Lark"
OKB: Phazotron NIIR
Chief Designer: G. M. Kunyavsky
Sapfir-23 twist-cassegrain antenna
Sapfir-23 was designed by a team under Chief Designer Kunyavsky for the MiG-23 fighter. A purely air-to-air design, it was the first radar for a frontal fighter designed to allow BVR engagements.
It used semiconductor technology rather than vacuum tubes and a method of external coherence in the mode "SDTs" (moving target selection) to detect aircraft flying below the host aircraft. This had limitations- it could only detect targets in the duration between successive pulses, and had multiple "blind" velocities in multiples of its PRF.
It used an analogue AVM-23 computer, and a twist-cassegrain antenna.
Some sources indicate that early versions could only detect closing targets. The incorporation of an IRST into the MiG-23 may therefore have been intended give a pursuit engagement capability.
Sapfir-23L was the radar of the initial production MiG-23 (1970-71).
Sapfir-23D was the full standard radar and the first with limited lookdown capability. Search range was 55km against a closing Tu-16 sized target, 45km against a MiG-21 in lookup mode. Tracking range was about 35km, again in lookup mode. Fitted to production MiG-23M. Lots of problems were encountered in service, as it required expert tuning and high quality maintenance. It wasn't uncommon for the detection range to vary 10 times from one set to the next. Weight about 500kg.
Sapfir-23D-Sh was improved with better discrimination of low flying targets and improved ECCM. Fitted to later production MiG-23M, older MiG-23M were upgraded to this standard. "S-23D-III" found in some sources is a mistranslation of this variant (caused by Cyrillic "Sh" character, which is three vertical lines joined at the base)
Sapfir-23E was fitted to MiG-23MF export variants. Based on Sapfir-23D with minor differences.
N003E Sapfir-23ML radar
N003 Sapfir-23ML was initially designed by G. M. Kunyavsky in the early-to-mid seventies, completed by Yury Kirpichev and introduced in 1976 as a major update to the Sapfir-23, after early service experience showed various deficiencies in the original radar. As part of a crash upgrade program, the radar was thoroughly modernised, increasing ECM resistance. The Sapfir-23ML's weight (around 350kg) was less than the original Sapfir-23, which helped improve the MiG-23's agility. Search range against a fighter was 55km in look-up mode, 20km in look-down mode. Against a Tu-16 (16 sq m), the detection range increased to 75-80 km and 22-25 km in look-up and look-down modes repectively. Tracking range against the same target was 46.5-50 km in lookup and 20-25 km in lookdown.
Yantar / Sapfir-23ML-2 was a variant designed for the MiG-29A, a cut-down MiG-29 intended to use existing technology to achieve IOC by 1979. Designed by Yuriy Figurovsky, it was a repackaged and slightly improved version of the MiG-23's radar. Difficulties in fitting it into the MiG-29 were overcome by enlarging the wing roots, but it was abandoned in 1976 along with the MiG-29A. All Phazotron's efforts were redirected to the urgent task of developing the Sapfir-25 radar.
N006 Ametist / Sapfir-23MLA / Sapfir-23PA was a further improved version of N003/Sapfir-23ML radar, used on the MiG-23MLA (?) and final production MiG-23P variants. Probably has most of the capabilities of Sapfir-23MLA-2.
N008 Sapfir-23MLA-2 was fitted to existing MiG-23s from 1984 during upgrade to MiG-23MLD (23-18 ) standard. Their whole avionics suite was greatly updated, including the radar, IRST, IFF, with the fitting of R-73 AAMs and an HMS. While some sources allege a multiple target track capability, former Soviet pilots deny this, and it is not true. MTBF (Mean Time Between Failure) was 60 hours.
N008E Sapfir-23MLAE-2 was the export variant of the above. It has three primary modes- search (with sub-modes for lookup and lookdown), single target track, and close air combat.
Close combat mode uses a vertical scan in two vertical bars – 6° in azimuth and +42/-1.5 degin elevation, up to 9 km in distance with semi-auto target track. The target has to be ‘put' into the HUD's (sight's) field of view. It is not good for tracking targets maneuvering at low level towards the ground due to excessive clutter. The radar antenna 'slaves' the R-60MK or R-73 seeker towards the target in this mode.
N008E also has two new search sub-modes. The first is called PSTs, used for better target discrimination in lookdown – with improved Doppler selection of moving targets at altitude above 50m (150ft) – useful for operations over mountains with high ridges or over urban areas which otherwise would generate strong false targets masking the real target. The second mode is called MPH – designed to counter chaff and cloud reflections at medium/high altitude, which would otherwise mask the real target.
Sapfir-23MR radar intended for the early Su-27 designs (T-10) with a fighter target range of 40-70 km lookup, 20-40 km lookdown in both front and rear hemispheres for a fighter target
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