For more detail this asset from the Unity Asset Store: Click Here
This is a paid asset, but now you can download FPS Hangar for FREE, Please keep in mind this package is provided only for learning purposes or to be able to test before buying the product, NOT FOR COMMERCIAL PURPOSES.
FPS Hangar v1.1
Industrial level kit. This paсk contains 1 large hangar, buildings with interiors, props like fences, metal stairs, crates. The package has a modular architecture from which you can build your own levels, such a hangar, storage containers, open industrial location, scene, combine and many other locations. – Preview of models and Scene ready for Unity 5 now with a sample scene
– All objects of this pack are made with high textures
– 43 Low poly models
– The pack has been successfully tested on mobile devices
– A complete high resolution level ready for implementation into first-person shooter
– 57 textures (2048×2048 (Albedo, Normal, Gloss, Metalness/Specular, Occlusion, Emissive, Height)