I've got a bunch of old electric RC planes. When last I flew them, they used Nicad or NiMh battery packs, and used 72mhz radios.

I'd like to upgrade the battery packs to lithium. I'm sure my old nicad/nihm cells are bad after many years of sitting. I'd think lithium would get me longer flight time, as well as less weight. But are people still flying the old 72mhz radios?

Looking at my old planes on the wall, I realized I might need to make some changes if the lithium batteries are much lighter to keep the center of gravity correct.

Still have my first RC plane, a Great Planes PT-Electric. It's been crashed once, upgraded the motor, added steerable nosewheel, and built a new wing with ailerons. Would love to get it back in the air. Back in the day, it was about 5 minutes flight time max on the largest battery I had.