George Patterson wrote:

I wonder if it would be possible to make inflatable floats that could be
deflated once in the air to reduce drag. Maybe a little electric air
pump to inflate them again before landing?

I looked at a T-Bird II that was forsale, it had inflatable floats that
were fed from the exhaust of the Rotax engine. Didn't look closely at
the rigging for that as it was hanging from the roof of the hanger...

The owner was deceased, but seller attested to seeing it work as setup...