That particular setup shows a smart-fly board with a receiver and fan attached to it.

I don't think that there are a lot of heat issues in jets since there is a good air flow inside the fuselage, but in IMAC type planes were everything is enclosed, there could be some problems if you leave your plane under the sun even for a short period of time.

According to some test that were done, the temperature at which some of the non-dotted receivers would stop working was very low so why take a risk ? I bought some small fans and installed them on the receivers. Do the fans help ? I don't know....... but at least I have peace of mind knowing that I did take precautions.

http://www3.towerhobbies.com/cgi-bin...?&I=LXMYJ0&P=7