Cameras for R/C airplanes are very much available. And you can also setup that uplink. However, you instantly convert your R/C airplane into a UAV or drone. Doing so will invite regulations like Charlie said.

However, you can record onto a SD or SDHC card. There are a number of videos online for that. Just ensure that you dont do it around a sensitive area such as a penitentiary, UN office or such. It will invite attention from the cops. For example, our field is located close to a high security prison (which is atleast a mile away) and though our airplanes cant even get there, we were banned from flying for 4 months in the last flying season due to a hi-profile trial. Now we have the cops visit us regularly on weekends

Ameyam