Looking for lightweight yet extremely strong RC glider recommendations.

Hello, I’m an Electrical Engineer with a personal research background in weather balloon systems, including designing payload systems with long range communications. I preface with this because I’m approaching an ambitious project: a high altitude balloon dropped glider that will attempt to autonomously glide to its launch site. I’ve seen this done by several individuals and teams alike after setting out with this goal, which has resulted in some really inspiring missions and footage.

The problem is, in terms of custom airframe design I wouldn’t have the faintest idea where to start. I’m also afraid of scope creep keeping me from settling on and manufacturing a design. The things I make tend to never be good enough for me. I was hoping someone with more experience and knowledge in gliders and autonomous systems of this nature could recommend an off-the-shelf glider airframe that could survive the journey to 33 km.

I’m looking to keep the airframe below 800 grams, as buying several dozen larger balloons and helium tank refills will set me back thousands. Thank you in advance for any help!

You probably want a “Pocket F3F” type glider, a small pylon racing slope soarer for example:

It should be able to fly fast to combat the high winds at altitude and be generally robust and also be efficient to get a good glide ratio. A slope soaring pylon racer seems to fit the bill exactly. These models can take some ballast, so you want to put as much ballast in as you can to get it to penetrate the high winds.