Ukrainian-Air-Force-Su-25-(Ukranian-Ministry-of-Defence)
A Ukrainian Air Force Su-25. A similar aircraft flown by the Armenian Air Force was shot down on 29th September.

The loss of an Armenian Air Force Su-25 Frogfoot prompts questions about the type’s survivability.

Despite its age the the Sukhoi Su-25 series (NATO reporting name Frogfoot) ground attack aircraft will celebrate four decades of service with the Russian Air Force next year. It deservedly retains its reputation as a rugged platform.

Only one such aircraft to date has been recorded shot down during Russia’s intervention in Syria’s civil war since the former commenced its deployment there five years ago. Su-25s flown by the Islamic Republic of Iran’s air force and the Iraqi Air Force have performed admirably in Northern Iraq fighting ISIS (Islamic State of Iran and Syria). Things have been slightly more fraught in the Ukraine theatre of operations: At least four Frogfoots have been shot down following Russia’s intervention in the Ukraine civil war from 2014.

On 29th September the Armenian Air Force lost a Sukhoi Su-25K and its pilot during an attack by a Türk Hava Kuvvetleri (Turkish Air Force) General Dynamics/Lockheed Martin F-16C/D Fighting Falcon combat aircraft. Tensions between Armenia and Azerbaijan in the disputed region of Nagorno-Karabakh betwixt both countries erupted into violence on 27th September.

Self-Protection Systems

Armada’s records indicate that Armenia’s Su-25Ks are equipped with GosNRTI’s SPS-15 radar warning receiver. Our data states that the SPS-15 covers a waveband of two gigahertz/GHz to 15GHz. It can show the pilot the bearing of a hostile radar, the type of radar the aircraft is being illuminated with and the radar’s operating mode.

Assuming that the Turkish pilot was using their radar during the engagement the SPS-15 should have warned the pilot that their aircraft was being tracked by the F-16C/D’s Westinghouse/Northrop Grumman AN/APG-66 X-band (8.5GHz to 10.68GHz) fire control radar.

Jamming could then have been performed using the aircraft’s Central Scientific Research Institute of Radio Technology’s L-203 Gardenia electronic attack system. Details are sparse on the L-203’s performance although sources familiar with Russian electronic warfare equipment have told Armada that the system should be capable of jamming X-band transmissions.

Even if the radar illumination had not been used during the engagement, Armenian Su-25Ks carry the ASQ-2V countermeasures dispenser. It is not known which organisation designed and built this equipment. Armada’s data says that four countermeasures dispensers equip the Su-25K positioned either side of the vertical stabiliser. These dispense flares and chaff.

It is not known at this stage how the F-16C/D performed the kill, although it seems reasonable to assume that this was done using Air-to-Air Missiles (AAMs). Countermeasures can be insufficient on their own to break a missile’s lock and the pilot will often have to use countermeasures in combination with manoeuvres to escape.

Thus, we are presented with three possibilities: Firstly, the pilot may have made errors on their countermeasure-manoeuvre response once under attack. Secondly, the aircraft’s countermeasures may have malfunctioned at the critical moment and not detected the attack or may have failed to cause the missile to lose lock. Thirdly, the pilot and countermeasures may have all performed properly but, for one reason or another, this was insufficient to protect the aircraft.

Explanations

On the one hand, the loss of the aircraft could be construed as raising legitimate questions over the performance of the aircraft’s countermeasures. However, to an extent, the Su-25’s combat record in recent years speaks for itself. Only one air-to-air loss of a Su-25 has been recorded. On 16th July 2014 a Ukrainian Air Force Su-25 was shot down by a Russian Air Force MiG-29 (NATO reporting name Fulcrum) fighter over Ukrainian territory. The Su-25 was said to have been downed with a Vympel R-27 (NATO reporting name AA-10 Alamo) semi-active/active radar homing and infrared guided AAM. Furthermore, as a ground attack platform the Su-25 was arguably conceived to support operations where the air-to-air threat was minima, or where top cover is provided by combat air patrols.

After the latest loss, it might be tempting to conclude that the Su-25 and its self-protection systems are past their best. A closer look at the aircraft’s combat record indicates that it continues to be a robust, well protected platform.

Self-protection systems are not designed to provide a combat aircraft with an impregnable shield. Instead, they enhance protection when used in combination with other factors most importantly a pilot’s tactical acumen. A pilot has been tragically killed and an aircraft lost, but one should not write off the Frogfoot just yet.

by Dr. Thomas Withington