the China Airlines Boeing 747 has very much noise in the sky. It appears that there are stripes running from top to bottom. Additionally, there are very little details in the darker sections. I would recommend to rescan your image, apply some blur to the sky (to get rid of the noise) and decrease the contrast a bit.
The Lufthansa Cargo has these vertical stripes, too, and there is quite an amount of grain visible. This shot however is much harder to fix as you cannot apply some blur to the mountain background.
You should also check your scanner because of these stripes.
Hope this helps!
FU Airliner Photography