Atomic ramjet for exploring Titan

Pat Flannery wrote:

Use a RTG, and you can seal the isotopes in ceramic and just use their
heat to drive some sort of power generator.
With its high atmospheric density and low gravity, Titan is the place
where you could literally float safely down to the ground under a
umbrella like in a cartoon, so the wings need not be very big in
comparison to the weight they can carry.

I just went digging to get some specifics on Titan's atmosphere;
pressure is 1.5 times that of Earth, the atmosphere is mainly nitrogen
(I thought it would be methane). Maybe airships filled with either
hydrogen or helium could also be workable for robotic exploration.
Gravity is only .14 g, even less than that of the Moon, so getting
something to generate enough lift via wings to keep itself flying in
this sort of environment should be a piece of cake.

Pat