F6 menu isn’t visible

[Migparts]

When creating a mission I select the dynamic cargo option and internal cargoes (only boxes- for some reason no fuel drums) are available.
I also place a howitzer nearby so that I sling load it. However, to start the sling process I need to hover above it and the F6 tab should appear. I only have F5 and F7. F6 all cargoes is missing. 
 

What should I do in my mission creation to enable a howitzer to release the red smoke and become ready for loading by the sling???

[Migparts]

That’s because in mission editor I needed to select static cargo. A ground combat item will not be loaded. All is good now. 

Edited August 16, 2024 by Migparts