Aerial warfare of the Zemplen War

A Drago (top) and Zephyr fighter (bottom), the primary fighter aircraft of Ruvelka and Syara respectively during the war.

Aerial warfare was a major part of the Zemplen War, with airpower playing a role in every major operation. Both the Ruvelkan Imperial Air Force and the Commonality Air Force fielded large air forces with modern aircraft, producing intense aerial combat that resulted in over 3,000 aircraft destroyed over the course of the conflict. Syara entered into the war with more fixed wing aircraft than Ruvelka but fewer fighters, allowing Ruvelka to absorb the initial air campaign and respond in kind, leveraging superiority in numbers to limit Syara's ability to influence the war in the air.

Syara's large fleet of fixed wing attack aircraft, as part of the intended role of the CAF as a primarily tactical air force, proved to be very vulnerable to Ruvelkan air defense systems and ground fire which led to heavy losses. Ruvelka began a strategic bombing campaign in mid-2009 known as Operation Eclipse, which targeted Syara's industrial production. Neither side was able to establish air superiority, but the RIAF's edge in numbers and more balanced organization allowed it to maintain an advantage over the CAF. As attrition set in both sides saw a significant decrease in sortie rates, peaking in May 2009 at nearly 2,600 per day before declining to just a thousand by spring 2010. The Zemplen War remains a major source of study for modern air forces across Tyran, and produced several aces on each side.

Opposing Forces

Commonality Air Force

By the summer of 2008 the CAF formed the fourth largest air force in Tyran after Acrea, Ossoria, and Cacerta. This included over 600 fighter aircraft and nearly 400 attack aircraft, with an additional 140 attack helicopters and 130 armed unmanned aerial drones. Syara's air force was composed of a mixture of Syaran and foreign designs. The most powerful aircraft fielded the CAF was the Ossorian made T-35 Séideán, which Syara had designated the Zephyr. Supplementing the Zephyr was the domestically built Ceyx, in essence a lighter version of the Zephyr that was the first aircraft produced by the Commonality. Both the Ceyx and Zephyr were delta-wing aircraft with close coupled canards that emphasized Syaran preference for low altitude flying and combat.

Air support was in theory meant to be provided by Syara's extensive arsenal of attack aircraft, the most common of which were the light aircrafts Corvus and Strix. Between 2001-2003 the CAF had judged the two designs as lacking in sufficient payload for high intensity air support, and in 2004 acquired 48 AFGSF-5 Tartaruga Ground Strike Fighters from Cacerta. This gave the CAF the largest fleet of attack aircraft in Tyran, and was expected to provide most of the air support to the Syaran National Army.

Syara's air defense forces were also large, and considerably more so than Ruvelka. Whereas the Ruvelkans saw air defense as integrated with operations by the Ruvelkan Imperial Air Force, Syaran air defense doctrine considered itself separate from the CAF and thus was responsible for protecting Syaran ground forces from hostile air power. On the eve of war the SNA fielded over 2,000 mobile surface-to-air missile launchers, in addition to over 1,000 self-propelled anti-aircraft guns. A further 1,650 towed anti-aircraft guns were allocated to Motorized Divisions, while over 12,000 MANPADs were distributed to Syaran troops.

Royal Acrean Air Force

Upon its entrance into the war in 2009, the Royal Acrean Air Force was the largest air force in Tyran by number of aircraft, with just over 2,000 combat aircraft of all types in service. It was composed entirely of domestic designs. The backbone aircraft of the RAAF's fighter fleet in 2008 were the EF-135C Draken and EF-167C Viper. They were supplemented by multirole EF-161E Raven. These three aircraft formed nearly the entirety of the RAAF's fighter squadron composition. They were supplemented in small numbers by the 5th generation EF-662A Vampyr which had entered service with the RAAF in 2006.

Dedicated strike capabilities were provided primarily by the EF/A-121 Vultur, a variable-sweep wing multirole interceptor first introduced in 1974, and was supported by a squadron each of 12 B-61 Wraith and 24 EFB-27 bombers which were deployed to Ruvelka but saw very little use as the RAAF bolstered Ruvelkan forces through conducting counter-air missions as opposed to strike or bombing missions. The emphasis on counter-air operations by the RAAF saw its fighter squadrons being deployed in areas of high CAF activity.

Probability of Kill

In aerial warfare, probability of kill (Pk) refers to the likelihood (expressed in numbers or percentages, such as 0.5 or 50%) of a successful "kill" on another aircraft when fired upon with an air-to-air missile. Numerous factors can influence whether or not an air-to-air missile (from here on referred to as an AA missile) will strike its target (the missile does not need to necessarily impact the aircraft physically to destroy it, as a nearby explosion and dispersion of shrapnel can also down an aircraft). This includes pilot skill (understanding when and where the best opportunity for the missile to hit), the maneuvers of the aircraft such as dodging and weaving to avoid the missile, weather conditions (sunlight and heat can impact the performance of infrared or heat seeking missiles), and countermeasures such as chaff or flares. Missiles may also fail due to poor maintenance or damaged components, reducing their effectiveness and the probability of kill.

In the early months of the war, the standard Pk rates across all missiles utilized by both sides varied between .10-.25; in other words, a successful shootdown of an enemy aircraft occurred in just 1/10th to 1/4th of the time, with the lower end range typically reflecting air-to-air combat between fighter aircraft and the higher end typically involving shootdowns of non-fighter aircraft by fighters. The low rate of fighter-on-fighter shootdowns was largely the combination of lack of experience and strategic posture. During the initial periods of intense combat during the August Offensive and Operation Aspis, both Syaran and Ruvelkan pilots were still learning about the capabilities of their own aircraft and that of their enemies in combat, along with their weapon systems and defensive measures. During early combat, Syaran pilots had little experience operating with the extensive jamming Drago flights typically employed, while Ruvelkan pilots were not prepared to handle Syaran tendency to dive to lower altitudes where their Zephyrs were more maneuverable. In addition, the decision of the Ruvelkan Imperial Air Force to avoid attempting to contest the airspace above the border to preserve air power for later battles meant that many Ruvelkan pilots declined to engage. The higher rate of 1-in-4 typically involved fighter aircraft engaging non-fighter aircraft such as ground attack aircraft, which were typically slower and less maneuverable.

As the conflict raged on, pilots became more familiar with the capabilities of the aircraft and weapons involved in the air war. This resulted in a steady increase in Pk rates throughout 2009, peaking during the heavy fighting of the Syaran Spring Offensives and the Ruvelkan Autumn Counter-Offensive. Pk rates during this period could range from .20 to .60. The range in this set was predominantly due to differences in pilot training. Pilots who were trained exclusively in air-to-air combat and maneuvers performed better than their counterparts who also trained and were employed as ground attack; Syaran Zephyr pilots averaged a Pk of over .60 during this time, compared to Ceyx pilots who averaged just about .30.

Pk also varied heavily depending on the nature of the combat. Syaran pilots preferred fighting at lower altitudes, where the close coupled canards on the Zephyr and Ceyx allowed for better vortices management and maneuverability. At these lower altitudes the Syarans enjoyed a significant advantage, winning nearly 70% of engagements at below 4,000 feet. At higher altitudes Ruvelkan pilots tended to perform better thanks to the Drago's superior speed and the Draken's emphasis on high altitude maneuverability. It thus became standard tactical procedure for Syaran pilots to dive down low once engaged to better employ their aircraft; Ruvelkan aircraft who followed also risked exposing themselves to increasing threats of Syaran air defense systems the lower they flew.

Towards the end of 2009 however Pk rates began to significantly decline largely due to decreased sortie rates and increased emphasis on force preservation. After nearly a year of extensive and continued combat, exhaustion of crews, pilots, and airframes saw significant declines in squadron readiness, in addition to increased wariness of exposing aircraft to unnecessary risk. Instances of pitched combat between fighters dropped off as pilots were instructed to avoid unnecessary engagements, resulting in most dogfights devolving to one plane each firing off a single missile before both aircraft broke contact, with Syaran pilots diving for the protection of their air defense network and Ruvelkan aircraft flew east beyond the Kurilla Mountains. During the final months of the war, Pk rates picked up as fighting intensified during Operation Homefront. By June 2010 however the Syarans were in retreat and the CAF was forced to commit to helping stall the Ruvelkan advance, leading to increased instances of air combat and shootdowns.

Despite the amount of resources and effort poured into it, air-to-air combat between fighter aircraft was relatively infrequent during the war. Rarely did two groups of fully armed and fueled aircraft engage one another on equal terms; rather patrols of fighters engaged one another usually while conducting other missions such as ground attack or air cover. It was more common for aircraft to engage on unequal terms where limitations in fuel and payload often determined the outcome of the engagement before any missiles were actually fired. In many cases pilots simply refused to engage and bugged out without firing or after only firing once, and as a result just 20% of air engagements actually resulted in a shootdown.

Pre-War Planning

The Commonality Air Force and the Ruvelkan Imperial Air Force both featured significantly different mindsets in the years leading up to the Zemplen War. Having studied the performance of the Syaran Army Air Corps during the Siduri War, the CAF determined that the Republic's medium bombers had failed in their role to provide a strategic bombing capability and considered such an effort a waste of resources. As a result, the Syaran Commonality Armed Forces Central Command outlined the primary role of the CAF as providing support for the Syaran National Army, primarily through close air support and air interdiction to prevent an enemy air force from gaining control of the skies. By emphasizing that any war would ultimately be determined by ground forces, the CAF was oriented towards the role of a tactical air force, lacking strategic bombers or interceptors in favor of multi-role fighters and attack aircraft.

The Ruvelkan Imperial Air Force by comparison pursued a more balanced approach, purchasing a large number of airframes and designs from Cacerta including strategic bombers and fighter aircraft. The RIAF felt that in the event of a war it needed the ability to contest all over the battlefield and beyond, and thus acquiring the AFSB-2 Spettro strategic bomber, which would later play a role in the war. Unlike the CAF, the RIAF primarily saw close air support as the role of its fleet of helicopter gunships, which proved to be better suited to the task than Syara's fixed wing attack aircraft. Prior to the war, much of Ruvelka's air command and control function was done primarily through ground control guidance, a design that was interwoven with airborne command and control in the months after the war began.

Fighter Aircraft

Both Ruvelka and Syara fielded hundreds of fighter aircraft during the war. Syara's primary fighter was the Ossorian T-35 Séideán, which had been acquired by Syara in the 1990s. The CAF designated the aircraft the Zephyr, intended to compliment the domestically designed Ceyx, which had been inspired by the T-35. Both aircraft were cropped delta-canard configurations, although the Ceyx was smaller and powered by a single engine. The Ceyx also lacked the same level of stealth and advanced avionics of the Zephyr but was slightly faster at lower altitudes. During the war the Ceyx gradually fell out of favor and was supplemented by the Zephyr, which was seen as the superior aircraft.

Ruvelka also fielded two fighter aircraft at the onset of the war, the older AFASF-10 Donnola, and the newer more advanced AFASF-12 Drago. While the Donnola had been slated to be retired, the outbreak of the war forced it back into service. Because of its limited role against Syaran fighters, the Donnola often acted as a ground attack, surveillance, or electronic warfare aircraft for the RIAF. The Drago by comparison was a superior dog fighter, while also capable of serving as ground attack the Ruvelkans preferred it for air superiority roles, and as such was the primary opponent of the CAF in the skies over western Ruvelka.

At the start of the war Ruvelka fielded approximately 800 fighters against Syara's 600. While this deficiency had been noted by the Syarans prior to the start of the war, efforts to rectify it were still underway when fighting broke out in the summer of 2008, giving the Ruvelkans a numerical edge that they would maintain for the duration of the conflict. Direct combat initially favored Syara; the Ceyx and Zephyr were both superior to the Donnola, and while the Drago could outclass the Ceyx in most engagements, the Zephyr held a number of advantages over its Cacertian designed counterpart. The Zephyr had a lower radar-cross section, making it more difficult to detect, while it's close cropped canards gave it significant maneuverability, especially at lower altitudes. Superior sensor infusion and situational awareness often allowed Zephyr pilots to outmaneuver Dragos in one-on-one combat, giving the Syarans an edge.

However, Drago pilots had a number of tricks to employ. Built as a dogfighter, the Drago remained exceptionally dangerous within visual range, a frequent occurrence in the ECM heavy environments in the Zemplen War. Faster than both the Ceyx and the Zephyr, Ruvelkan pilots could also make extensive use of "boom and zoom" tactics to outfly their Syaran adversaries. Additionally, Ruvelkan superiority in numbers often allowed Ruvelkan pilots to avoid one-on-one engagements. Ruvelkan Dragos would often employ "kürt fészek" (hornet nest) tactics, usually involving 2-4 Dragos flying together, with one operating an ECM/EW pod while the other aircraft closed in and engaged Syaran aircraft at short range. While the Zephyrs maintained a positive kill-ratio over Ruvelkan fighters throughout the war, Ruvelkan tactics are widely considered to have mitigated Syaran advantages in aircraft design.

Beginning in mid-2009 Ruvelka began acquiring EF-135A Drakens from Acrea to supplement the RIAF. A total of 24 aircraft in two squadrons were purchased and saw extensive service during the war. Designed exclusively as an air superiority fighter, the EF 135 could match and defeat the Zephyr, especially at high altitudes where the Acrean design was at home. Like the Drago, Ruvelkan pilots were trained to make use of the Draken's speed and rapid acceleration to their advantage. After losing nearly a dozen fighters to the EF 135, Syaran pilots began responding to encountering the aircraft by rapidly diving to lower altitudes, where the EF 135 was less capable than the Zephyr. This had the added danger of exposing the EF 135 to Syaran air defense systems, which resulting in the shoot-down of three EF 135s in late 2009 and serious damage to another. As sortie rates on both sides decline, the CAF continued to emphasize low level flights, which saw the EF 135 transfer primarily to the role of overwatch for other Ruvelkan aircraft. Because it was also a delta-canard aircraft, the EF 135 was the cause for several friendly fire incidents on both sides of the war.

Despite the frequency in which air-to-air combat occurred, actual losses from these engagements was usually low. The CAF estimated that in fighter-on-fighter engagements, confirmed kills occurred in less than 20% of all dogfights, a conclusion the Ruvelkans also found once factoring out their kills on Syaran attack aircraft, which were slower and more vulnerable.

Strategic Bombing

Lacking any kind of strategic bomber, the CAF did not attempt to initiate a strategic bombing campaign of Ruvelka during the war. Ruvelka, on the other hand, fielded several Spettros. During the initial stages of the war they saw only limited usage, primarily as close air support for the Ruvelkan Imperial Army. Following losses in Operation Harpe and the Battle of Sagerejo, Debrecen authorized the RIAF to begin a strategic bombing campaign designed to inhibit Syara's war making ability. Known as Operation Eclipse, Ruvelkan Sprettros sortied out to hit targets within Syara, mainly known supply depots and manufacturing centers.

Eclipse proved controversial for a number of reasons. The decision to attack targets in Syara itself dampened international support for Ruvelka somewhat, as Syara had attacked Ruvelkan industrial centers behind the front lines prior. Ruvelka defended the decision as a necessary strategic decision given recent developments. More controversy revolved around the choice of targets, which were primarily civilian sites. Over 100 Syaran civilians were killed in the bombing raids, which led the Government of Syara to denounce the campaign as "terror bombing". Syara further declared it would prosecute the crews it had captured as war criminals, although no action was ever taken and the crews were exchanged along with all other prisoners after the war.

Apart from the controversy of the bombings themselves, contention remains over the effectiveness of Eclipse. Most analysts conclude that Eclipse did not significantly impact Syara's industrial output, nor did it noticeably hamper Syaran supply efforts. Ruvelka nonetheless concludes the campaign was partially successful, as it drew away Syaran resources, air defense systems, and aircraft away from the front. Eclipse began on 22 July 2009 and concluded on 14 November the same year. Ruvelka carried out a total of six air raids, hitting targets across eastern Syara. Three Spettros were shot down, with another two damaged, killing six crew with another five captured. 147 Syarans were killed in the raids, with 312 wounded.

Close Air Support

Both Syara and Ruvelka approached close air support with different mindsets and doctrine. The CAF viewed air support as best being carried out by fixed wing attack aircraft, which were relatively cheap and could be armed with a variety of weapons. The Republic of Syara had produced two domestic light attack aircraft, the Corvus and the Strix, for the purpose of carrying out close air support for the Syaran Army. In 2004 Syara also purchased 48 AFGSF-5 Tartarugas after evaluation and testing. As fighting broke out across the border multiple squadrons of attack aircraft were called up to support the Syaran ground forces as they advanced into Ruvelka and continued to play a major role in all Syaran operations.

Syara's attack aircraft however proved exceptionally vulnerable to Ruvelkan air defenses, with the Corvus and Strix especially threatened by ground fire. Syaran attack aircraft quickly piled up heavy losses, in many cases strike packages suffered losses in excess of 50%. The decimation of Syara's attack aircraft fleet led the CAF to repeatedly attempt to pull them from front line service, but the Syaran National Army, desperate for air support, insisted on their continued operation. The SNA's insistence won out, forcing the CAF to commit its attack aircraft in spite of appalling losses. Of the 525 fixed wing armed aircraft the Syarans lost, 339 of them were attack aircraft. The heavy losses suffered by Syaran attack aircraft led to the CAF halting production of both aircraft after the war and declined to purchase more Tartarugas. As the war progressed the role of CAS in Syaran doctrine became increasingly focused on helicopter gunships and drones, which were more survivable in contested airspace due to their versatility. The Zephyr, which included capable air-to-ground strike ability became a popular choice for air support for Syaran ground forces. However the already shorthanded Zephyr was never in large enough supply to perform both CAS and air interdiction, forcing Zephyr pilots to take on excessively heavy mission loads to fulfill both demands.

Ruvelka in comparison had long held the role of CAS was to be fulfilled by helicopters, a decision that was largely validated by their experience in the Zemplen War. Close air support was occasionally provided by Dragos and Donnolas, but Ruvelkan commanders often expressed a preference for helicopter support, which they considered more reliable and accurate. Ruvelka also made use of UAVs for air support, though to a lesser degree than the Syarans.

Helicopters and Unmanned Aerial Vehicles

HH3 attack helicopters of the Ruvelkan Special Air Service.

Helicopters formed the cornerstone of Ruvelkan tactical doctrine, with heliborne forces being an essential aspect of many Ruvelkan operations. As detailed above, helicopters also formed the primary means of close air support for Ruvelkan ground forces, a task they were well suited to due to Ruvelka's oft rugged and mountainous terrain where the ability to hover was paramount. Ruvelka fielded three primary attack helicopters, the Halászsas, the Sólyom, and the Lódarázs. The Halászsas was the most common attack helicopter fielded by the Ruvelkans, prized for its ability to function both as an attack helicopter and a troop transport. It was heavily employed by the Ruvelkan Imperial Fusiliers, operating as transportation for infiltration teams targeting Syaran forces behind the lines, especially artillery and staging depots. While prized by Ruvelkan commanders for its tactical utility, its reputation among pilots was somewhat more mixed due to the aircraft’s lackluster agility and maneuverability compared to other attack helicopters, rendering it more vulnerable to Syaran air defenses. With 343 destroyed during the war, it suffered the highest losses of Ruvelkan helicopters.

The HH2 Sólyom enjoyed a more positive reputation and was feared by Syaran troops for its usage as a stealth and infiltrator gunship, often flying at low levels to sneak through Syaran lines and striking against supply lines. Usage of the Sólyom was more restricted however as the single-seat helicopter asked a lot of its pilot, requiring stringent and vigorous training standards. The Sólyom was thus used more sparingly than the HH1, and often directed towards more high priority targets. A total of 37 were shot down or destroyed during the war.

The HH3 Lódarázs was the most basic of the three designs, being a more generalized attack helicopter. It remained however a very functional aircraft, with more advanced sensors and avionics than the HH1 while being crewed by two rather than the demanding single-pilot HH2. Although it did not have a specific function, it performed its role well and provided fire support for Ruvelkan forces throughout every major operation of the war. The most direct Syaran counterpart was the Philomela, which had been jointly produced with Tennai before the war. The Philomela originally had a minor role in Syaran airpower, but after the decline of Syara's attack aircraft the Philomela came to be a vital source of CAS for Syara.

Both sides utilized unmanned aerial vehicles extensively. Ruvelka employed a wide variety of designs, from small handheld drones for supporting Fusilier infiltration teams, to larger armed variants for fire support. Syara fielded larger numbers of drones and larger drones in general, often using them for artillery spotting, battlefield surveillance, and a number of UCAVs for fire support, which along with attack helicopters gradually supplemented attack aircraft as the primary source of CAS.

Both sides lost hundreds of UAVs and helicopters. Syara recorded the loss of 286 helicopters and 678 UAVs during the war, while Ruvelka lost 722 helicopters and 259 UAVs, with their respective losses reflective of their doctrinal emphasis within each nation's doctrine. The Zemplen War also saw the only major instances of helicopter-helicopter direct combat.

Air Defense

Air defense systems were utilized extensively by both sides during the conflict. Syaran Army units were liberally supplied with air defense systems, with dedicated air defense forces assigned to each brigade and division. Ruvelkan forces by comparison tended to centralize their air defense systems, making extensive use of cover and concealment in Ruvelka's rugged terrain to help avoid Syaran air power. Air defense systems came in a variety of forms, from the Ruvelkan LR1 SAM, to the Syaran Pollux, Daedalus, and Calliope systems. Originally limited in their capacity, anti-aircraft artillery in the form of self-propelled anti-aircraft guns, became increasingly common in response to the proliferation of UAVs and helicopters.

Ruvelka and Syara approached air defense operations, and SEAD and DEAD efforts, differently. Ruvelka tended to view air defense as part of a combined effort with air power, and thus integrated combat air patrols into their air defense networks. Syaran air defense forces by comparison operated largely independently from the CAF, with Syaran aircraft augmenting rather than supplementing air defense networks. Syaran air defense systems were prolific in their usage and employed in every major operation, and thus were a frequent target for Fusilier infiltrators and strike missions.

Because of the scale of the conflict and the large amount of systems and aircraft involved, neither the CAF nor the RIAF attempted any conflict wide SEAD or DEAD campaign, instead focusing on local efforts to support active or impending operations. Air defense systems were a major contributor to air losses during the war; the SCAF estimated that air defense systems were responsible for roughly 70% of aircraft shootdowns during the war, a view that most Ruvelkan analysts concur.