Has anyone tried to do this with whistle mouthpiece adapter? There’s been some discussion of this in the Flute forum: http://chiffboard.mati.ca/viewtopic.php?t=21123
There are melody flutes that have a fipple on the side.
I made one in Low-D, the short windway was little breathy sounding.
The nice thing about is that you can angle down about 45 degrees and still play it. On regular flutes, my hands get tired of being in the air too long.
I’ll see if I can find a picture.
Here it is:
Daniel, is that mouthpiece molded plastic?
Better off just learning the flute embouchure. Although it takes some time to learn, it has some distinct advantages.
Yes, it is better to learn the embouchure, but I am thinking of the day that perhaps I lose all my teeth - maybe in an accident or something and can’t afford implants (knocking on wood to prevent that from happening 
). They say it’s very hard to play the flute with dentures.
And even if I keep my teeth, surely there’s some benefit in a side-blown low whistle. Lots of people complain about the difficulty in finger positions on low whisltes.
Daniel, maybe you could make a clip-on whistle mouthpiece for flutes?
There is a trade off. A flute is typically much easier to play with the ordinary whistle fingering than a low whistle. OTOH, a low whistle is much easier to hold than a flute although Daniel suggested that he’s at least partially addressed that problem. But the main reason is the one Paul gave although he didn’t elaborate. An experienced flute player can coax a lot more tonal variety out of a flute than you can get with a whistle.
The mouthpiece is made of round brass tubing, rectangular brass tubing and shaped and held in place with sculpey clay baked on a PVC coupler with flute embouchure hole drill in it.
Yeah, what he said!
BTW-- Walt Sweet showed up at the Northeast gathering and had a wood low D whistle along with him. Attached to it was a removable adapter made from plastic pipe fittings which lets you play it transversely like a flute.
Walt’s idea is that this makes fingering a low whistle easier since it puts the hands and wrists, especially the right, in a more natural position. I gotta say it seems to work very nicely, although the adapter is butt ugly. 
It’s held on by the friction of an O-ring, so it just slips on and off easily. Very clever, Walt.
Do I sense a challenge coming on for man who’s not only got wood but who knows how to work with it?
Is there a way to get a picture of this adapter?