I&#x27;ve been wondering why passenger planes and military cargo planes have so different layout?<p>So far my best guess is that it&#x27;s related to landing gear. Landing gear makes significant portion of the total weight, you want to keep it short and compact. Engines are the heaviest things in passenger planes, so landing gear is close to engines.<p><a href="http:&#x2F;&#x2F;i.telegraph.co.uk&#x2F;multimedia&#x2F;archive&#x2F;03137&#x2F;plane_3137447b.jpg" rel="nofollow">http:&#x2F;&#x2F;i.telegraph.co.uk&#x2F;multimedia&#x2F;archive&#x2F;03137&#x2F;plane_3137...</a><p>With cargo plane the heaviest part of the plane is the cargo.<p><a href="http:&#x2F;&#x2F;cdn23.us2.fansshare.com&#x2F;photos&#x2F;antonovan124&#x2F;antonov-an-low-level-flight-cargo-plane-wallpapers-wallpaper-256058768.jpg" rel="nofollow">http:&#x2F;&#x2F;cdn23.us2.fansshare.com&#x2F;photos&#x2F;antonovan124&#x2F;antonov-a...</a><p>It seems bit weird that one of the most dictating thing to airplane layout is not really related to flying itself. But I could be wrong on this one. Does anybody know better?