The primary goal of Fliegerkorps VIII in the south, aside from providing ground support, was the neutralization of the JKRV. Attacks on airfields were planned to try to catch the Yugoslav planes on the ground, but this was less than perfectly executed as the Yugoslavs were expecting the German attack. The Luftwaffe did gain some successes in the south as 17 Me 109's of I(J)/LG 2 with a few Me 110's of I(J)LG 26 attacked the Furies of 32 Grupa, destroying 11 Furies and damaging two more while losing one Me 109 and two Me 110's, including one that was rammed by a Fury. A similar effort was planned for 35 Grupa, but the Me 109E's couldn't find the well- camouflaged Furies and had to settle for destroying the 16 Breguet XIX's of 2 VI Grupa at a nearby airfield. The Do 17K's of 63 Grupa at Petrovac suffered a similar fate with German attacks leaving only four Do 17's flyable.

Upon hearing of the disaster which befell their sister unit, 64 Grupa immediately took off and bombed the German armor which was still in a 17 mile-long column in Bulgaria, but without much effect. While waiting for their next target, 64 Grupa was strafed by 10 Me 109's that destroyed or damaged 15 Do 17's. Total losses by Fliegerkorps Vill for the day included seven Me 109's, two Me 110's, two Ju87's, two Do 17's, two Hs 126's and a Hs 123, although this includes losses due to accidents.

In the North the primary mission of Luftflotte 4 was to punish the Belgrade government, as per Fuhrer Directive 25. A massive punitive mission of 74 Ju 87's and 160 He 111 P and Do 17Z bombers of KG 2, 3 and 4, escorted by Me 110's of I/ZG 26 and 100 Me 109's of JG 54 and 77 was intercepted by 29 Me 109 and 5 IK-Z fighters of 32 and 51 Grupa. The Yugoslavs lost seven Me 109's and two IK-Z's in this first combat.

Additional raids continued throughout the day, with German losses totaling one Me 109, five Me 1 10's, two Do 17's and four Ju 87's. The Germans continued to bomb Belgrade throughout the night, dropping a total of 360 tons of bombs. The 4 and 6 VI Grupa were essentially annihilated by Ju 87's of II/StG 77 escorted by Me 109's of JG 77, one of which was shot down by flak.

The Yugoslav defenses in the west were limited to some AA guns and the nine fighters of the Independent Fighter Eskadrila at Mostar. Attacks by 4 Squadra Aera and Fliegerkorps X based in Italy and Sicily destroyed only two Avia BH-33's, two SM.79's and damaged several more aircraft for the loss of a Cant Z.1007bis and a Ju 87.

The Yugoslav bombers played little part in the day's activities. Aside from the ill-fated Dorniers, only a few sorties were flown. Targets in Austria, Albania, and Rumania were attacked with little result for the loss of four Blenheims. Sorties for the day totaled 474: 377 by fighters, 93 by bombers, and 4 by recon planes. Losses totaled 47 fighters, 45 bombers, and 3 reconnaissance planes destroyed or damaged.

The fighters defending Belgrade took their toll of the German attackers on 7 April, but suffered in the process, shooting down three Ju 88's and a Do 17 while the JKRV lost eight Me 109's shot down and others damaged. Two Hurricanes of the Independent Fighter Flight intercepted a small formation of Ju 88's, but were bounced by escorting Me 109's and shot down. With the fighters flying defensive patrols, the bombers flew unescorted missions against Hungarian airfields, Austrian railroads, and German columns in Yugoslavia losing nine Blenheims shot down by fighters and flak, and eleven more damaged. Meanwhile 3 and 7 VI Grupa and 201 Training Grupe were wiped out by marauding Me 110's and Stukas.

On 8 April, the Yugoslav bombers in the south concentrated their attacks on the 8 mile long column in the Kacanik Gorge. The low cloud cover forced everyone but the SM.79's, who found gaps in the clouds, to attack from underneath the cloud base at 300-500 feet where they were vulnerable to small-arms fire.

Three Blenheims, one Hind, one Do 17, and one Hurricane were shot down or crashed.

Heavy snowfalls on 9 April prevented aircraft from flying except in the north where III/JG 54 shot down two Hurricanes and one IK-2 of 4 Puk for the loss of one Me 109. The Italians attacked the seaplane base at Tijesno, destroying three Sim XIV's and damaging two more. The rumor of approaching German troops caused 31 Grupe to burn their snowbound Me 109's, only to discover that the Germans were still some 40 miles distant.

Similar rumors on 10 April caused most of the Yugoslav aircraft still serviceable to attempt to fly to more secure bases in marginal weather. Three Hurricanes, two Blenheims, one Do 17, and a SM.79 crashed during these attempts.

With morale low due to the overwhelming power of the Luftwaffe and the Croatian uprising, several aircraft attempted to flee the country on 11 April. Eight SM.79's of 7 Puk attempted to fly to Russia, but only four reached that country, the others crashing or landing in Hungary. A Do 17 also landed in that country, while one Yugoslav pilot defected with a Blenheim which was used as a light transport for several years. One Do 17 was flown to Bulgaria where it was absorbed by the Royal Bulgarian Air Force.

12 April saw the destruction of much of the remaining aircraft of the JKRV as Me 110's of I/ZG 26 strafed Bjeljina, where aircraft of 6 Puk and 11 Grupa had flown for refuge, destroying 17 Blenheims, three Hurricanes and the Breguet XIX's of 1 and 6 VIGrupa. Another two Hurricanes, two Blenheims and a Do 17 either were shot down or crashed while flying their missions.

On 13 April German units entered Belgrade while the Luftwaffe attacked troop concentrations.

The Italians attacked Mostar airfield, destroying several SM.79's and a Me 109.

The Germans captured Bjeljina airfield in a coup de main on 14 April when 17 Ju 52's, escorted by 11 Ju 87's, 23 Me 110's, and 18 Me 109's, landed troops which swiftly overwhelmed the defenders; they captured 210 Yugoslavs while losing 3 dead and 4 wounded.

The Yugoslavs started an "air bridge" to Greece on 15 April with the few remaining serviceable aircraft, mostly Do 17's, Do 22's, and SM.79's. The Yugoslav government fled to Greece via the air bridge along with much of the country's gold reserves. Two Hurricanes, two Furies, a SM.79, and a Do 17 were captured along with numerous trainers and 28 floatplanes. Approximately 40 aircraft of all types reached Greece, but many were destroyed by the enemy once their airfields were discovered. Only four SM.79's, two Do 17's, eight Do 22's, and a Sim XIV escaped the German onslaught and reached Egypt.

The SM.79's were assigned to 117 squadron where they supported the route between Takoradi, the Gold Coast, and Khartoum, Sudan by which most of the aircraft delivered to the Middle East. The last one was written-off in January 1944. Of captured aircraft, the Italians only recovered one airworthy SM.79, but another had escaped to Hungary where it was exchanged in 1942 for 2 CR.42's.

The Do 22's served as 2 (Yugoslav) squadron under R.A.F. command. Some 40 pilots flew out to join the Allies, as well as some 200 aircrew.

The saga of the Yugoslav aircraft was not quite over as the Croatian Air Force used several Blenheims that were repaired by Ikarus after the collapse of organized resistance, but serviceability was low and they rarely flew. Also, eleven Do 17 Kb-11's, were ultimately transferred to the Bulgarian Air Force from the Croatian Air Force.

Order of Battle - 6 April 1941
Unit	Base	Equipment	Supporting
Vrhovna Komanda [Air Force High Command]
11 Ind. Grupa	Ruma	9 Blenheim 1, 2 Hind	21 & 22 Eskadrila [Flight]
81 Grupa	Mostar	14 SM.79	261 & 262 Eskadrila
Ind. Fighter Eskadrila	Mostar	3 Hurri 1, 3 Me 109E, 3 Avia BH-33E	-
1 Lovacka Vazduhoplovna Brigada [Fighter Air Brigade]
2 Puk [Regiment]:
31 Grupa	Susicko Polje	19 Me 109E	101 and 141 Eskadrila
52 Grupa	Knic	15 Hurricane 1	163 and 164 Eskadrila
6 Puk:
32 Grupa	Prnjavor	27 Me 109E	103, 104, and 142 Eskadrila
51 Grupa	Belgrade	10 Me 109E, 6 IK-Z	102, 161, 162 Eskadrila
2 Mesovita Vazduhoplovna Brigada [Mixed Air Brigade]
4 Puk:
33 Grupa	Aleksandrovac	13 Hurricane 1	105 and 106 Eskadrila
34 Grupa	Aleksandrovac	7 Hurricane 1 and 8 IK-2	107 and 108 Eskadrila
8 Puk:
68 Grupa	Rovine	12 Blenheim 1	215 and 216 Eskadrila
69 Grupa	Rovine	12 Blenheim 1	217 and 218 Eskadrila
3 Mesovita Vazduhoplovna Brigade
3 Puk:
63 Grupa	Petrovac	30 Do 17K	205-207 Eskadrila
64 Grupa	Petrovac	30 Do 17K	208-210 Eskadrila
5 Puk:
35 Grupa	Kosancic	15 Fury	109 and 110 Eskadrila
36 Grupa	Rezanovacka	15 Fury	111 and 112 Eskadrila
4 Bombarderska Vazduhoplovna Brigada [Bomber Air Brigade]
1 Puk:
61 Grupa	Davidovac	11 Blenheim 1	201 and 202 Eskadrila
62 Grupa	Bjeljina	12 Blenheim 1	203 and 204 Eskadrila
7 Puk:
66 Grupa	Preljina	13 SM.79	211 and 212 Eskadrila
67 Grupa	Gorobilje	13 SM.79	213 and 214 Eskadrila
Army Aviation (all equipped with Potez 25 and Breguet XIX):
1 VI Grupa	Ruma	16 planes	1st Army
2 VI Grupa	Sorlince	16 planes	5th Army
3 VI Grupa	Staro Topoije	19 planes	2nd Army
4 VI Grupa	Kurilovac	18 planes	4th Army
5 VI Grupa	Tetovo	14 planes	3rd Army
6 VI Grupa	Brezice	16 planes	7th Army
7 VI Grupa	Sm. Palanka	18 planes	6th Army
Coastal Army Commando : Mostair : 4 planes
Naval Aviation:
2 Hidroplanska Komanda [Floatplane Command]
3 Hidrogrupa:
5 Hidroeskadrila	Tijesno	5 Sim XIV	-
25 Hidroeskadrila	Zarina	Do 22Kj, 1 PVT-H	-
4 Hidrogrupa:
26 Hidroeskadrila	Krapanj	5 Do Wal, 1 PVT-H	-
15 Hidroeskadrila	Vodice	2 Sim XIV, 6-7 10, 1 Sim/XII	-
3 Hidroplanska Komanda
1 Hidrogrupa:
1 Hidroeskadrila	S. Krtole	5 Sim XIV	-
11 Hidroeskadrila	S. Rosa	2-3 Sim XIV, 1 He 8	-
2 Hidrogrupa:
20 Hidroeskadrila	Orahovac	6 Do 22Kj	-
21 Hidroeskadrila	Dobrota	6 Do Wal, 1 Do D, 2 PVT-H	-

4 more Blenheims were undergoing overhaul at the time of the invasion, but reached 11 Grupa before the end of the campaign.

Abbreviation: VI Gruppa= Air Recon Group

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