Second Box straddled centre of M/Yards with D/H's

Sortie Report (Form 541)

Date: 21st March, 1945

APPENDIX "Q"119From : S.I.O. 21 Squadron S.A.A.F.To : H.Q. M.A.A.F. (Attention Operations Records)H.Q. M.A.T.A.F.( SCORU)W.I.O. 3 Wing S.A.A.F.Ref. : 21S/973971Date : 21st March, 1945Oprep No. 971 for the period ending 2100 hrs. on the 20th March, 1945.Ref. Map. Yugoslavia 1:100,000 Sheet 28 - SAMOBOR.OPERATION NO. 173/21S/M.A : 10 A/C airborne between 1328 and 1700 hrs to attackDOBOVA M/Yards 10 miles N.W. of ZAGREB. One A/C returned earlywith engine trouble after 30 min. Remaining nine A/C in(three Vics) picked up an escort of 4 Mustangs at Cerviaand attacked briefed target from 12500' at 1527hrs on acourse of 060°. First box undershot, pattern falling in opencountry and ending 50 yards short of western portion of thetarget. Second Box straddled centre of M/Yards with D/H'son rolling stock and tracks. Third Box's runup was interferedwith by another A/C resulting in a bad right error; butpattern appeared to commence on a stationary train on theeastern approach to M/Yard. 10 - 15 bursts of inaccurateH/A/A from target area.Two further A/C (accompanied by two of 30 Squadron) briefedto attack the gunpositions in target area immediately priorto main formation's T.O.T. carried 192 x 20 lbs frag. bombs.Pattern of 1st A/C commenced with an undershoot but ended ingunpositions; 2nd A/C had a very slight left error withpossible or near misses in target; third A/C had a near misspattern to the right of his briefed position - these guns wereobserved to cease firing three seconds before bombs exploded;stick of fourth A/C unobserved due to steep turnoff. Four A/Cairborne between 1337 - 1719 hrs; T.O.T. 1526 1/2 hrs; height ofattack 12000'.B : (1) 12 Marauders III (ii) Nil C. (1) & (ii) NilD : (1) 38.20 hrs. (ii) Nil. E. (1) 40800 x .50 (ii) & (iii) NilF : (1) 60 x 500 fused 30 - 51 Tail.(ii) 54 x 500 29 Pkts Pamphlets40 x 250 " " " 36 x 250 720 lbs Window384 x 20 lbs frag. 384 x 20(iii) & (iv) NilG to V : NilW : (1) 6 Marauders III (ii) Nil X(1) 6.05 Hrs (ii) NilY to Z : NilS. L. Bosch [Signed]Capt.S.I.O. 21 SQUADRON S.A.A.F.Handwritten Marginalia / Stamps:

Folio Number: 119 (Handwritten, Top Right).

Reference Stamp:The National Archives' reference AIR 27/271/3

Transcriber's Notes

S.I.O: Squadron Intelligence Officer. Captain S. L. Bosch was tasked with debriefing crews and compiling OPREPs.
Mustangs: North American P-51 Mustang fighter aircraft provided for close escort duties.
Window: Chaff; aluminum foil strips (720 lbs dispensed) used to degrade German radar-directed anti-aircraft fire. Operational Context Target File 271-3_35 documents Operation No. 173/21S/M on March 20, 1945, a major strike against the Dobova Marshalling Yards in Yugoslavia. Located 10 miles northwest of Zagreb, Dobova was a critical logistical bottleneck for German forces moving materiel between the Balkan and Italian theaters. This raid was a component of Operation Bingo, the strategic interdiction campaign intended to paralyze German Heeresgruppe C by severing all supply and transit nodes. The tactical methodology of this raid illustrates the maturation of principles established during the 1943 battles for the Bernhardt and Gustav Lines. In November 1943, 21 Squadron S.A.A.F. utilized high-intensity strikes on bottlenecks like location H055630 to prevent German reserves from reaching the front. By March 1945, the sophistication of these strikes had increased. The Dobova mission involved dedicated Anti-Flak aircraft dropping fragmentation clusters specifically to suppress defensive batteries 30 seconds before the main formation's arrival. The success of this coordination is evident in the report that German guns ceased firing three seconds before the fragmentation sticks impacted. Despite mechanical failure (one aircraft returning with engine trouble) and formation interference, the second box achieved kinetic success with direct hits on rolling stock and tracks. The mission further integrated psychological warfare through 29 packets of pamphlets and extensive electronic warfare via 720 lbs of Window, maintaining relentless pressure on the decaying Axis logistical network. 36

MC/GP (Medium Capacity / General Purpose): Standard high-explosive ordnance, here including 500 lb and 250 lb variants, utilized for demolition of rail infrastructure.

MC/GP (Medium Capacity / General Purpose): Standard high-explosive ordnance, typically 500 lb and 250 lb variants, carried by SAAF crews to destroy physical industrial infrastructure and rolling stock.