yellow warning T.I's

[Marcel L.]

David, anyway, thanks for your help. Do you think that the warning T.Is were usually dropped at turning points, so the change of direction towards Dusseldorf in this case?

[David Wallace]

When they did route marking it was usually for a large operation, marking a turning point or a position the main force would begin their target run. It wasn’t unusual to see route marking sorties using Oboe but their normal operations were marking the aiming points for the main force or doing precision bombing. My father flew 73 Oboe operations with 109 Squadron in 1944 and none of his sorties involved route marking.

[Alex Smart]

How about Target Indicators ?

[David Wallace]

They used target indicators when they were marking aiming points for the heavy bombers as well as when they marked routes..

[David Wallace]

Marcel - I checked the 3 Group Form B for this operation and there is a note on it:
“Preliminary warning ground markers T.I. yellow will be dropped by Mosquitos at 51.01N. 06.33E as an aid to navigation.” .
This may make more sense, perhaps the NRR had a typo on the route marking location. My father was a Navigator on a Stirling for this op.