From our support templates:
"The site was started in the late 90s with photos of airliners. As time has progressed, we have expanded to cover any aspect of aviation.
People have different interests and we wish to serve everybody equally.
If you look at the top photos and photographers' choice, you'll see that many of the most popular photos are in fact not of airliners, but rather military planes. This shows that having these aircraft types in our database is much welcomed among our users.
You can always choose to see only civil aircraft when searching for photos, by choosing "Civil Only" in the Photo Search Engine here: