XenonS: If you own F15 Strike Eagle II (also from Microprose), you can add these scenarios into F19 to play them. For that do the following:

In your F19 game folder, copy and make a BACLUP of these files in a 1st folder named CEUROPE:
CE.3D3
CE.3DT
CE.3DG
CE.WLD
CEUROPE.SPR

From your F15_II files, copy in a 2nd folder named VIETNAM and rename into:
VN.3D3 > rename into CE.3D3
VN.3DT > rename into CE.3DT
VN.3DG > rename into CE.3DG
VN.WLD > rename into CE.WLD
VN.SPR > rename into CEUROPE.SPR

From your F15_II files, copy in a 3rd folder named MIDEAST and rename into:
ME.3D3 > rename into CE.3D3
ME.3DT > rename into CE.3DT
ME.3DG > rename into CE.3DG
ME.WLD > rename into CE.WLD
ME.SPR > rename into CEUROPE.SPR

If you want to play Vietnam scenario, copy all files from Vietnam folder into your F19 folder and overwrite. In F19 chose Central Europe (which is wrong but who cares...) and you are go to play Vietnam. Same with Middle East scenario. When you want to play Central Europe again, copy back the files from the CEUROPE folder-

have fun!

Note: The Desert Storm scenario from F15_II cannot be transfered that way, it will not work.