I am a gate agent at BNA for American Eagle. We service both CRJs and ERJs. We have been told in our training that the skin on the CRJs and ERJs is too thin to actually touch the aircraft with the bridge or the moving weather canopy. Therefore it is American Eagle's policy to use the adapter.

Our jetbridges are old American bridges that have the auto level feature which we are also not allowed to use because it requires that an extesion arm touches the aircraft to judge when to move the bridge up and down.