

PZL P.24





Тhe Bulgarian aviation traces its origins as early as in the late XIX century. The attempts of Yorchi Sabev of Malomir village and Elisey Petkov of Khotnitza were closer to the dreams rather than to the reality. The free flight pioneers tried to construct hand-made wings to fly like birds. As expected, their naive experiments were unsuccessful as was the effort for a balloon construction in the city of Razgrad in 1880. However, these air pioneers and enthusiasts inaugurated the aviation idea in Bulgaria, which soon developed into reality.
By this time, the main achievements in the flying science were well-known in Bulgaria. Aerostatics is the first branch of this science, dealing with the devices and conditions of flying in the air of objects in accordance to Archimedes principle on the free floating. The second one is the aviation (derived from the Latin word avis, denoting bird), a science on flying which deals with the principles and construction of flying craft, lifting in the air thanks to the mechanical principles based on performing a certain quantity of mechanical work. Aviation idea’s propaganda and popularization in Bulgaria ran in parallel with the first steps of indigenous aviation science (1880 - 1903).
In 1902, Kharalambi Djamdjiev carried out the first serious study on the theory of flight, which transitioned into practical realization. He is known to had developed two theories on flying - the first one based on the reflecting-parabolic principle (explaining how birds fly) and the second one on the hydro-aerodynamic vacuum principle. Kharalambi Djamdjiev has also offered projects for both aircraft with waving wings and airplane employing fixed wing.
The beginning
On 19 August 1882, the city of Plovdiv witnessed the opening ceremony of the First Agricultural & Industrial Fair. The famous French aeronaut Eugene Godard was invited to demonstrate his balloon named La France. On August 31, in presence of Prince Ferdinand, he took to the air for the first time into Bulgarian sky, raising over the enthusiastic public. This is the reason to consider that 31 August was the date on which the Bulgarian aeronautics was formally born.
Vassil Zlatarov was the first Bulgarian officer to fly on La France. Later on, he became the organizer and chief of the young Bulgarian military aviation and aeronautics forces. He was the first Bulgarian to fly on glider (1904) and on airplane (15 November 1910), and is known as the first glider and kite designer in Bulgaria.
In 1903, Vassil Zlatarov initiated the formation of the Aeronautics Section subordinated to the Bulgarian Army Engineering Forces, and on 22 June was nominated its Commander.
Bulgarian Army’s first balloon section was formed on 22 February 1906. Six years later, its personnel was tasked to construct in four months the first Bulgarian-made balloon named Sofia One, after the country’s capital. It made its first climb out on 1 August 1912, and one month later took part in Forth Exercise held near the city of Shoumen, and then saw use in the Balkans War.
1911 was the year of the formation of the Bulgarian Army aviation branch. It was a common view by that time that aviation’s use in anger is forthcoming. The combat aviation was expected soon to be turned out into the ‘eyes and ears’ of the army, designed to operate in ‘rushing, decisive and hard-beating’ manner.
As expected, the Bulgarian Government preparing the war against Turkey, took a prompt resolution to acquire aircraft and sent pilots and technicians for training abroad. Ministry of War Order of 3 April 1912 published the names of 17 officers selected for pilots. Their flying training was carried in several countries: France (Bleriot Flying School in Etampes, Military Aeronautics School Sapre Aerostiers in Paris and Voisin company), Germany (Albatros company) and Britain (Bristol company).
Seven aircraft were initially purchased to form the first Aeroplane Section within the structure of the Bulgarian Army, thus marking the formal beginning of the Bulgarian military aviation. The section was based at an airfield located north of Sofia Railway Station, and was reporting to the Engineering Forces Command. First Lieutenant Toprakchiev was nominated its first Commander. A single French-made Bleriot XXI airplane was delivered in July 1912; it became the section’s first aircraft; First Lieutenant Simeon Petrov was the Bulgarian pilot to fly solo for the first time in home airspace on 12 July.
Shoumen Forth Exercise held between 7 and 10 September 1912, immediately before the beginning of the Balkans War, saw the Aeroplane Section participating in its full size. The sole airplane was used by the offensive party in cooperation to the attacking force and the aircrews proved capable to reveal the defending force’s positions. As expected, their operations during the exercise were praised highly by the Bulgarian Army commanding officers.
Amongst the First in the World
Bulgaria’s strong army established its own aviation element in 1910-1912, during major territorial disputes with Muslim Turkey. The Balkans War (1912 - 1913) was widely considered liberation war in Bulgaria. On 12 September, during the mass mobilisation, the Aeroplane Section was ordered to relocate its sole Bleriot XXI aircraft to an airfield near Tarnovo Seimen city. On 11 October, it deployed near the village of Moustafpasa (now known as Svilengrad), in close proximity to Second Army headquarters. A number of recently delivered aircraft were assembled and flight-tested. All Bulgarian pilots and technicians, most of them just graduated from foreign schools, were posted there together with several foreign volunteers willing to participate in the war on Bulgarian side. Thus, when the war had started, the Bulgarian aviation inventory numbered some 21 fully assembled and combat-ready aircraft, and by the end of the war, the number of aircraft grew to 29. The aircraft brought by the foreign volunteers and those captured during the battles eventually increased the figure to 35.
The young Bulgarian aviation force comprised various aircraft, made by Bleriot, Voasin, Albatross, Nieuport, Farman, Sommer and Bristol. These were both single and two-seat ones, monoplanes and biplanes, featuring maximum speed up to 110 km/h and practical ceiling up to 1,500 m, and were powered by piston engines rated between 35 and 100 hp.
During the army advance in the first stage of the conflict the available aviation, assets were grouped in three aeroplane sections:
1st Aeroplane Section was retained at its initial location at Svilengrad airfield. It was assigned to the Second Army HQ, which was tasked with the siege of Odrin Stronghold; First Lieutenant Radul Milkov was nominated Commanding Officer.
2nd Aeroplane Section was formed on 3 November 1912 and was deployed to the airfields at Chorlu, Kabakcha and Cherkezyoy. It was assigned to the Third Army HQ and First Lieutenant Dimitar Sekelarov was nominated Commanding Officer.
3rd Aeroplane Section was formed on 10 November 1912 and was deployed to the airfield around Malgara and then to Ursha. It was assigned to the Fourth Army HQ at Bulair Front; First Lieutenant Penyo Popkrastev was nominated Commanding Officer.
The three sections were assigned to the Aeronautics Park, commanded by Major Vassil Zlatarov and integrated into the Railway Battalion structure. The Park was also responsible for the control over the balloon section as well as over the supply service dealing with spare parts, fuel and lubricants.
On 16 October 1912, two Bulgarian pilots - Radul Milkov and Prodan Tarakchiev - flying an Albatross F-2 biplane performed what may have been the first real combat mission in Europe, against a heavily defended target. They were tasked with air reconnaissance of the heavy defended Odrin stronghold and then bombed the neighbouring Karaagac railway station dropping a couple of hand grenades.
Besides other occasional bombing missions during this war, the Bulgarian pilots flew regular visual and photo reconnaissance gathering missions, and the first ‘intercontinental’ mission over the Asian side of Istanbul - as well as the first anti-shipping bombing mission and leaflet dropping missions. Artillery fire correction was another important mission type performed by the brave Bulgarian pilots. In fact, Bulgarian aviators proved the combat effectiveness of heavier-than-air craft during the Balkans War.
Lieutenant Toprakchiev was the first casualty amongst Bulgarian pilots. He died as his aircraft crashed during a combat mission on 19 October. It is of note that the 15-year-old nurse Raina Kasabova flew on 30 October during leaflet dropping mission onboard of an aircraft piloted by First Lieutenant Stefan Kalinov; this may have been the first combat mission with woman’s participation.
The what may have been the first group combat mission in the world was performed on 14 November as four-ship formation, made by the pilots Radul Milkov, Nikifor Bogdanov, Stefan Kalinov and the Russian volunteer Nikolay Kostin bombed Karaagach railway station near Odrin.
The notably successful combat operations of the young Bulgarian military aviation attracted a lot of interest all around Europe. Tens of military correspondent and experts, including aviators are known to have been dispatched to the Balkans War battlefields in 1912 and 1913; they were tasked to study and analyse carefully the air combat operations, pioneered by the Bulgarians.
During the Balkans war the Bulgarian aviators revealed and proved the ways for aircraft multi-role combat employment: single and multi-ship flights in tactical and operative depth over the enemy territory, air reconnaissance, photo survey, bomb drops against manpower, defensive installations and other inventory on the battlefield and in depth of enemy-held territory as well as for artillery fire correction. The principles of centralised and de-centralised control over aviation units were proved as well as the close cooperation with the land forces.
The Balkans War a victorious one for Bulgaria and had led to the London Peace Treaty signed on 17 May 1913. A month later, however, another war commenced between the yesterday’s allies of the anti-Turkish coalition. The Bulgarian military aviation was not able to take part in this conflict due to the lack of prepared airfields and shortage in fuel, lubricants and spare parts supply. On May 1913, the 3rd Aeroplane Section and majority of the 1st Section were rebased to Drama region and were merged into a single unit which received the number plate of the 1st Aeroplane Section. The 2nd Aeroplane Section was rebased to Sofia, and on June 10 was stationed near the village of Slivnitza while the Balloon Section went the airfield near the Central Railway Station in Sofia.
Following the end of the Inter-Allies War, both the Aeroplane Sections were disbanded and then reorganised into one Airplane Company while the balloon unuts were grouped into the Balloon Company, a division of the Aeronautics Park, which was incorporated into the structure of the Technical Battalion of the Engineering Forces. The Aeronautical Park was commanded by Major Zlatarov and based north of Sofia Railway Station. In 1914, the first aviation school was established there and its sole instructor was the Italian citizen Giovanni Sabelli; he worked as an instructor pilot in Bulgaria until July 1915.
A new airfield was built in 1914 near the village of Bojurishte, located some 10 km northwest from Sofia and not before long it was developed into a major aviation centre. By late 1914, the aviation school and the repair shop were also relocated there.
The Bulgarian aircraft building traces its origins from early 1915 when the aviation technician Ilya Mladenov and the pilot Stefan Kalinov built an aircraft by their own design named Dogan, which was similar to the French-made Voisin. However, their undertaking was unsuccessful as Dogan crashed during its first test flight killing the pilot Stefan Kalinov. In fact, the first successful aircraft of Bulgarian design was built by the young Assen Jordanov, which took the air on 15 August 1915 piloted by Radul Milkov. This date was announced by the War Ministry as the formal Bulgarian Aircraft Building Day.
Victories and Losses
Bulgaria entered the World War One on October 1, 1915 participating as a strong German ally; the aviation element grew to battalion size, comprising three companies equipped with German-supplied second-hand combat aircraft.
The Bulgarian Army stated an offensive towards Greece and Serbia, and then was dragged into a positional war against the Allies, on the so-called Macedonian theatre.
During the war, the Bulgarian Air Force inventory accounted to as many as 100 aircraft. These were:
L.V.G.-B.II - 12 aircraft, the first six of which were delivered in November 1915;
Otto C.I - 13 aircraft, the first of which were delivered in August 1916;
Albatross C.III - 18 aircraft, the first of which were delivered in August 1916;
DFW-C.V -12 aircraft, the first of which were delivered in August 1917;
Roland D.II - 6 aircraft, the first of which were delivered in July 1917;
Roland D.III - 6 aircraft, the first of which were delivered in late 1917;
Fokker E.III - 3 aircraft, the first of which were delivered in the spring of 1916;
Fokker D.VII - 8 aircraft, the first of which were delivered in September 1918;
Fridrichshafen FF_33 floatplane -8 aircraft, delivered n 1916;
Rumpler 6B-1 floatplane - 2 aircraft, delivered in 1916;
Albatross C.I - 2 aircraft, captured in 1915 during their ferry flight from Germany to Turkey.
The Fokker D.VII fighters were not used in anger since these were delivered just before the end of the war. Seven of them were destroyed in accordance to Paris Peace Treaty in 1920, and the only survivor was hidden and later was use by the reborn Bulgarian military aviation. During World War One, Bulgarian pilots also flew on many occasions Albatross D.III and Halberstadt combat aircraft, based at Ksanti airfield, but these belonged to the German air force and none were formally delivered to the Bulgarian air arm.
The Bulgarian pilots flew thousands of combat missions over the Macedonian theatre against the Allied forces. The first air-to-air combat was performed by Capt Tarakchiev on 21 April 1916. On 30 September 1916, the Bulgarian Air Force scored its first air victory. Lieutenant Marko Parvanov flying a Fokker E.III fighter, assisted by the German instructor pilot Wagner, successfully intercepted and shoot down a French Air Force Farman 40 bomber which was on a raid against Sofia.
A total of 60 air-to-air encounters were recorded by the Bulgarian pilots during the war, and air five victories have eventually been scored. Five more enemy aircraft were captured lightly damaged together with their aircrews. Own losses accounted to five pilots and two observers. Three Bulgarian aircraft made forced landings on territory held by the enemy, but their aircrews have successfully burned out the machines and escaped capture.
The Bulgarian Naval Aviation saw its establishment in 1916 - in the form of the Floatplane Section based at Peinerdjik (Tchaika), on the side of Devnya Lake near the city of Varna.
Crash and Rebirth
After the end of World War One, Bulgaria was prohibited from establishing any military aviation structure for 20 years. The 1919 Paris Peace Treaty called for almost complete demolition of the Bulgarian armed forces. Almost the entire air force inventory - a total of 70 aircraft, 100 aero engines and 76 machine-guns - was destroyed under the strict control of the Allied occupation corps. The floatplanes were the last aircraft to be destroyed, in September 1920.
The country was restricted to buying civil aircraft from the Allies, as the power rating of their engines was restricted to 180 hp. Several World War One-era airframes and engines, however, were hidden and later clandestinely used for training. In 1921, the military aviation was ‘hidden’ into the Gendarmerie Aeronautics Section, a paramilitary structure controlled by the War Ministry. However, it was disbanded in 1922 following the strong protest by the French authorities, but was to be soon restored under the new name as Aeronautics Section, controlled by the Ministry of Railways, Post and Telegraph. The first new aircraft were acquired in 1924 and during the same year, King’s Decree of 15 July 1924 reformed the section into Aeronautics Directorate of the Ministry of Railways, Post and Telegraph.
In order to provide its ‘hidden’ air force with cheap but modern trainers, reconnaissance and light attack aircraft, in 1925 the Bulgarian government established at Bojourishte near Sofia an indigenous aircraft factory -DAR. In 1931 Caproni established its own factory in Kasanlak named Bulgarski Caproni.
In the mid-1930s, when it became absolutely clear that Europe was on the edge of a new large-scale war, both King Boris III and the Bulgarian Government took active steps towards the creation of a capable air force. The formal rebirth of the Bulgarian Air Force took place on 27 June 1937 at Bojourishte airfield. King Boris III handed the standards of the four newly-formed regiments (wings) as he donated 12 Dornier Do 11 bombers and 12 Arado Ar 65 fighters paid for from his own pocket. The other aircraft of the emerging air arm were 12 He 51 fighters and 12 He 45 reconnaissance aircraft, delivered in late 1936. 12 Polish-made P.Z.L. P.43B reconnaissance and close support aircraft (an export version of the P.Z.L. P.23) and 12 P.Z.L. P.24 fighters were taken on strength in 1938 and 1937 respectively. 36 P.23Bs were delivered in 1939 and two more in 1941. In total, 72 combat aircraft were purchased until the end of 1938.
The three-year and rather ambitious plan for the Bulgarian Air Force development called for the establishment of large-size air arm, headquartered in Sofia and composed by four composite regiments - 1st based at Ikhtiman airfield, 2nd at Plovdiv, 3rd at Yambol and 4th at Lovetch. Other units to be established in accordance to this plan comprised the independent regiment at Bojurishte airfield, naval aviation unit in Varna or Bourgas and training regiment based in Kazanlak.
The 1938 Thessaloniki Treaty between Bulgaria, Britain and France finally abolished the Paris Treaty limitations on the development of the Bulgaria’s military aviation. Soon after the beginning of the war Bulgaria eventually turned toward the Third Reich as the sole supplier of defence equipment.
By that time, however, the Reich’s aviation industry was busy to supply the Luftwaffe with state-of-the-art front line aircraft; therefore it was able to offer mainly newly built trainers and recce aircraft, and only a small number of modern fighters and bombers. These were insufficient for building up of a strong air arm of the Kind Boris III envisaged. The solution to the problem was found by means of the procurement of the remains of the air force inventory of what was known until 15 Marct 1938 as Czechoslovakia and later as the Reich’s Bohemia and Moravia Protectorate. A total of 214 aircraft of the former Czechoslovak air arm was delivered. These comprised 62 second-hand Letov-Smolik S 328 reconnaissance aircraft, 32 Avia В 71 (a licensed Tupolev SB version) and 12 Aero MB 200 (licensed Marsel Bloch MB 200En-4 version) medium bombers as well as 29 Avia В 122 trainers and one Aero В 304 photo ship. In the summer of 1939 the Bulgarian air arm ordered 78 brand new Avia В 534 biplane fighters and one year latter another agreement was signed for the local assembly of 12 Avia В 135 fighters, followed by large scale licensed production. Between 1936 and 1941 the RLM itself supplied a total of 203 aircraft -19 Messerschmitt Bf 109E-4, 12 Heinkel He 51, 12 Arado Ar 65 and 6 Focke-Wulf Fw 56 fighters, 18 Dornier Do 17 and 12 Do 11 bombers, 8 Fw 58 and 12 He 45 reconnaissance aircraft, 2 Junkers Ju 52/3M transports, 6 Bf 108 and 3 Fieseler Fi 156 liaison aircraft, 6 He 72, 40 Fw 44, 12 Bucker Bu 181 and 24 Ar 96 trainers. The indigenous aircraft industry provided the Bulgarian air arm with a large number of various trainers, recce and light, attack aircraft. Between 1936 and 1941 a total of 154 units were delivered - 24 DAR-3, series I, II and III and 46 KB-5 recce aircraft, 28 KB-4 trainer/recce aircraft, 10 KB-309 twin-engined training bomber and reconnaissance aircraft as well as 13 DAR-8 and 26 KB-2A/3 trainers.
Another peacetime reorganization of the Royal Bulgarian Air Force took place on 1 December 1939. The Army regiments with composite structure were reformed into single-role combat units: 1st Line Regiment at Bojurishte with three 12-aircrfat squadrons; 2nd Fighter Regiment at Karlovo with four 12/15-aircfrat squadrons equipped with the Avia B.534; 3rd Reconnaissance Regiment at Yambol with four 9/12-aircrfat squadrons equipped with the Letov S.328; 5th Bomber Regiment with three squadrons - 2 with 12 B.71 bombers and one with 12 Dornier Do 11.
In the summer of 1940 the fist batch of 12 Messerschmitt Me 109E-3 fighters were acquired together with six Me 108B-1 liaison and conversion training aircraft. A total of 145 Me 109E-3 and Me 109G-2/6 were taken on strength until mid 1945. The capability of the fighter force was eventually boosted up with the procurement the second-hand Dewoitine D.520s. These were initially intended to be employed for the air defence of the Reich, but in August 1943 the fighters were sold to Bulgaria. 100 units were planed to be delivered in September and these were to be followed by 24 more later that year. In fact 96 D.520s were eventually delivered. These equipped 2/6 and 4/6 regiments at Karlovo airfield, which commenced their conversion in November. The modernisation of the bomber force took place in September 1940 with the delivery of the first batch of 18 Dornier Do 17Ps, and the first Ju 87R-2 dive bombers entered service in December 1943.
In March 1942, a new organisation was purposely created to control all the front-line units - the Air Escadra. It was an Air Combat Command - like structure controlling the 2nd Line Regiment (latter renamed the 2nd Attack ‘Stuka’ Polk, equipped with two squadrons of Ju 87D/R attack aircraft and B.534 fighters re-roled as attack aircraft), 5th Bomber Division (with two regiments equipped with Do 17 and B.71s) and the 6th Fighter Regiment (with two regiments equipped with Me 109E/G and D.520). The 1st Reconnaissance Regiment (with two regiments equipped with S.328, Fw 189 and KB-11 and one long-range reconnaissance squadron equipped with the Do 17) was placed under the direct control of the Royal Bulgarian Air Force headquarters. The other direct-reporting air units of the air arm were the Air Transport Squadron (equipped with the Ju 52/m3), the Floatplane Squadron (with Ar 196A-3 and He 60) as well as the Flying School with various types of trainers.
First Battles
The first air combat between Bulgarian fighters and US bombers took place on 1 August. This day the 9th Air Force started the Tidal Wave operation on the suppression of oil production in Ploesti region in Romania. 165 B-24 Liberator bombers lacking any fighter escort were involved in the 1 August bloody raid, plotting their route trough the Bulgarian airspace. A flight of four Me 109G-2s intercepted a group of about 20 returning B-24s over northern Bulgaria. The followed several firing passes resulted in the shoot down of five or four B-24s, two of which on the score of First Lieutenant Stoyan Stoyanov. For his brave leadership and the double B-24 kills, the formation leader First Lieutenant Stoyanov was awarded the Bravery Cross.
On 12 August the most potent Bulgarian fighter unit - 3/6 Regiment, equipped with 16 Me 109G-2s was deployed to Bojourishte, assuming the responsibility for the air defence of Sofia. The ground-based air defence of the capital was strengthened to 56 88-mm AAA guns by late 1943.
In the autumn of 1943, the Allies launched the Point Blank strategic air offensive against Bulgaria. The main aim was that bombings would cause severe political instability followed by a prompt break away with the Axis, thus denying the already battered German armed forces from the use of Bulgarian bases and resources. The main target in the country was Sofia, on which 10 large-scale bombing raids were launched from 14 November 1943 to 17 April 1944 by the Italy-based 15th Air Force.
The fiercest air combat during the 1943 raids on Sofia occurred on 20 December 1943. Three formations of a total of 50 B-24s, escorted by similar number of P-38s, approached Sofia. By 12.30 the first of the 16 Me 109Gs of 3/6 Regiment took off from Bojourishte simultaneously with the lead element of the Vrazhdebna-based 24 D.520s of 2/6 Regiment. For the first time the two fighter units were ordered to fight co-operatively. The later started the first firing pass run against the lead enemy group approaching from southwards; ignoring the escort, the D.520 mounted deliberate head-on firing passes, followed by the Me 109Gs. Most of the bombers of the southern group hastily dropped its ordinance when engaged before to reach Sofia. The brave pilot Lieutenant Dimitar Spissarevsky attacked a small group, which approached the southern outskirts of the capital. Flying a Me 109G-2, he made a deliberate firing pass on one bomber and then undertook an intentional suicide ramming on another B-24 within the same formation.
The Bulgarian pilots achieved 10 confirmed kills (seven P-38s and three B-24s), and according to the official Bulgarian records, damaged at least five more enemy aircraft. Their own loses numbered two pilots and a pair of Me 109G-2s. The 20 December air battle was the most efficient air defence operation by the Bulgarian fighter force, as 10 per cent of the enemy aircraft participating in the raid were confirmed shoot down.
On 10 January Sofia was again the main target for the Allies. This was the most devastating air raid, followed for the first time by another one in the night. These were tasked to resist the heaviest Allied strike to the date, which caused considerable devastation of the city center. The strike package of about 150 B-17s, escorted by about 100 P-38s approached Sofia from the eastwards. The followed 20-minute air combat with the P-38s left the bombers without fighter escort thus allowing 32 D.520s to run on them just over Sofia. Their head-on firing passes scattered the first B-17 group but the next ones were able to carry out their bomb drops without fighter resistance thus causing severe devastation of the densely populated centre of Sofia.
The Allied bombing raids carried out between April 1941 and September 1944 resulted in 1,828 killed and 2,372 wounded Bulgarian citizens. Some 50,000 high explosive and incendiary bombs were dropped on Bulgarian territory. The Bulgarian fighters continued their actions against Allied bombers overlying Bulgaria on their way to and from Ploesti in the summer of 1944. The most successful summer air combat occurred on 17 August when 3/6 Regiment scored four confirmed and one probable B-17 kills.
Thus, the final combat record of the Bulgarian fighter force between 1 August 1943 and 9 September 1953 reached 53 confirmed kills, among them 37 four-engined bombers as well as 16 P-38 and P-51 fighters. Four four-engined bombers were claimed by the AAA. The damaged aircraft and probable kills numbered some 70 bombers and 22 fighters. Some of these crashed or force-landed on their back route over Serbia, Albania and the Adiratic Sea. Some 117 wrecks of Allied aircraft shoot down during their strikes on Bulgarian and Romanian targets were located on Bulgarian territory. The Me 109Gs and the D.520s of the 6th Fighter Division accumulated about 970 combat sorties. 550 of them were flown by the pilots of 3/6 Regiment, 275 by 2/6 Regiment, 90 by 1/6 Regiment and 52 of 4/6 Regiment. Bulgarian loses numbered 27 fighters and 23 pilots. More than 30 fighters made forced landings due to extensive combat damages.
The Patriotic War
After the pro-Allied coup of 9 September 1944, Bulgaria turned against Germany and all airworthy aircraft including a total of 146 aircraft, including 53 fighters, 33 attack aircraft, 32 bombers and 28 reconnaissance aircraft were engaged in close air support of the ground forces attacking Axis positions in Serbia, Macedonia and Greece. Main types used in the Patriotic War were the Me 109G fighters, Ju 87D dive bombers, Dornier Do 17 bombers and reconnaissance aircraft plus a host of support and liaison types.
In the early days of the ground offensive, the aircraft inventory available daily numbered between 80 and 100 but as the time had passed by, this number steadily dwindled. The lack of enough ground attack aircraft and the virtual absence of Luftwaffe fighters in the theater made possible the fighter units to switch to low-level attack role where they suffered from heavy attrition due to the dence AAA cover. A secondary combat task was the escort of both Ju 87D and Do 17 strike groups.
The first combat actions of the VNVV in the anti-Nazi new war took place by the mid-day on 9 September. A total of 35 combat sorties were flown. The Air Escadra was ordered to mount pre-emptive air strike against the Luftwaffe airfield at Nish and also to provide close air support to the 15th Infantry Division of the 1st Bulgarian Occupation Corps in Macedonia, which was encircled by the German troops near the city of Biloya. The Nish strike, carried out by three Me 109Gs of 3/6 Regiment resulted in six Luftwaffe fighters destroyed on the ground. The own loses numbered one aircraft and its pilot. 6 Do 17s of 1/5 Regiment, and 9 Ju 85D-5s of 1/2 Regiment mounted effective strikes in order to help the 15th Division to penetrate the surrounding and to initiate its retreat toward the Bulgarian border.
Subsequent strikes were carefully planned, in cooperation with the Soviet 17th Air Army, which was re-based in the northern part of the country and around Sofia in mid-September. The demanding mountainous terrain and the rapidly deteorating weather in the southern Balkans in the autumn were familiar to the Bulgarian air crews, so they were considered better suited to operate in this region at low level than the Soviets. The Bulgarian Air Force was tasked to provide close air support to the Bulgarian Army divisions advancing in the mountainous region of southern Serbia and Macedonia. The 17th Air Army was restricted to operations in central and northern Serbia and then in Montenegro. In order to prevent the incidents and loses from friendly fire - for the majority of the Bulgarian aircraft were German-made - the two air arms were planed to operate concurrently in non-overlapping zones. Within the few common operating zones they were ordered to operate at different times.
After the end of the battles in southern Serbia and Macedonia, the 1st Army joined the 3rd Ukrainian Front of the Red Army advancing toward Austria via Serbia, Croatia, Slovenia and Hungary. The German-made Bulgarian Air Force inventory was suffering from severe unserviceablity by the end of 1944, and the front-line aircraft were not able to participate in the battles, which happened more than 1,000 km away from Bulgaria. The close air support of the 1st Army was provided by the Soviet 17th Air Army. The air assets of the 1st Army were grouped in a liaison squadron of two Fi 156s and one Me 108 based at Zemun. One Do 17P of 73rd Long Range Recce Squadron flew reconnaissance and liaison missions in March 1945. Ju 52/3Ms flew some transport missions in support to the 1st Army. One Fi 156 with its crew of two was lost on 10 May to enemy small arms fire.
In air combat, and on the ground, the Bulgarian pilots destroyed 25 Luftwaffe combat aircraft. During 3,744 ground attack, air cover and recce sorties, they destroyed 690 tanks and combat vehicles, 25 artillery batteries, 23 locomotives and 496 railway cars. The total number of sorties, flown by the VNVV during the Patriotic War reached 4,424. 3,374 of these were flown during the first stage of the war between 9 September and 2 December, losing a total 32 downed or heavy damaged aircraft and 18 crew members.
By BAFP