50 kg is not hard with no other restraints; more data is needed otherwise put it in the back of a cessna. 50kg with a 1 meter wingspan would be a challenge. Is this for a school project or commercial project? Is it one lump or can it be spread out? All that stuff matters.
Is there a size limit? The highest lift at a given speed is achieved with multi element airfoils. Google for "CH 710" to see an example. There are NACA documents in PDF format showing how to design them.