Hi. I guess this is a silly questions, but it just occured to me to ask it on the forum and see how you other guys deal with it.
How do you guys hang on to your whistles when playing C#? Hah hah hah!! I try to “bite down” on my whistle with my lips, but I must confess that I sometimes lose my whistle or fumble with it right in the middle of a piece! I guess alternatively, one could grip on to it between finger hole–but I would be worried about restricting air and making a note go flat.
Right hand pinky.
I do this as well, but some people keep their right-hand ring finger down.
I am a pinkie guy myself, but putting the right hand ring finger down does not alter the pitch.
I shudder at the thought of biting onto a fipple (that isn’t to say, I haven’t done it before…I’m so ashamed.) The RHP is primarily what I use, but on occasion, I will use a few more fingers to get more stabilization. Most of the times however, I use OXOXXX, instead of half-holing.
I always keep my right pinky down to stabilize the whistle—I always feel I need it there. Some people have said that this limits the freedom of movement of your fingers. That didn’t seem to be a problem as far as I could tell, but I haven’t gotten that far on the whistle. I wouldn’t hold it between my lips or teeth. You could accidentally make funny sounds. I’ve never heard that being recommended.
Initial answer…“it just happens.”
Upon more thought…“bottom hand fingers. Sometimes just pinky, and perhaps, sometimes, all three fingers, but ten again I divert to my original response…‘It just happens.’”
I must admit that I find rolls/taps on E very hard to do with my pinkie down. I keep it down most of the time, but if I have to do that kind of intense right-hand-ring-finger work, it comes up automatically. I’m sure it looks a little funny.
As I recall, though, I’ve seen Kevin Crawford do something very similar when he plays whistle. For a closer look, there’s a nice clip of him playing (a susato!) in the “Pro-files” section of Phil Hardy’s website.
Congrats, I remember reading in my Grey Larson book that you have to lift your pinky for doing a tap on E. You can’t lift your ring finger high enough otherwise—well, obviously you know that. But it doesn’t look strange I’m sure. Everyone must do it that way. That muffin looks mighty tasty! 
I shudder at the thought of biting onto a fipple
Well, I sort of “bite” down with my lips–not my teeth…
I will use a few more fingers to get more stabilization. Most of the times however, I use OXOXXX, instead of half-holing.
I was talking specifically of Csharp on a D whistle which is all hole open.
i tried and tried the rhp method but it screws up my coordintion so for c#i just cover the bottom hole or all three bottom holes if i’m heading that direction
ooo oox is my usual
ooo xxx sometimes when i’m coming from or going to a D
ooo xxo sometimes when i’m coming from or going to an E
ooo xoo sometimes when i’m coming from or going to an F
ooo ooo holding with lips occasionally.
Basically whatever works easiest for any given passage.
I never use my fourth fingers at all as i just feel it adds extra confusion to the mix. 6 fingers is enough to worry about at this speed. 
I hold the whistle more or less horizontal when playing a tune that will require C sharps. I don’t think I keep the right hand pinky down very much at all.
It’s funny: My first response to this question was–what’s all the fuss about? My thinking was that the whistle just stays balanced on my thumbs. So, I picked up a whistle and just discovered that I use my pinky. I had no idea.
Ah, you know, I’m learning so much about myself.
Right hand pinky, both thumbs, and the lips themselves give the whistle four points of contact.
It’s quite stable–as long as the whistle isn’t slippery!
–James
I keep the ring finger of my right hand down in most tunes. It doesn’t affect the tone. Sometimes I may use 2 or all 3 fingers on my right hand. It depends on what I am playing. My pinkies are never used. See what works for you.
Ron
When I have to do a C#, I keep both of my thumbs on the bottom of my whistle and push up, and I keep my left pinky on the top of the bottom end pushing down. With the fipple in my mouth my whislte stays in place.
My pinkie finger kind of doesn’t reach.
Huh? I’m not able to get an image of that.
We’re talking about high D whistles here, right?
Yes, high D whistle. It’s worse on a flute, believe me. My pinky just floats artistically in the air . . . as if I were drinking tea.
If you have squarish hands with short, stubby fingers which all extend nearly the same distance from your wrist, you can cover all the holes and have your pinkie on the instrument at the same time.
I have lovely, long, slender hands with lovely, long, slender fingers. My index finger extends 7.25 inches from my wrist, the third finger 7.5, the fourth finger 7, but the pinkie only barely 6. And, add to that they are arrayed in a delightful and artistic curve . . . and you have a pinkie that won’t reach the instrument without substantial strain. Unless I cover the holes with nearly the second joint of the other fingers. Or cramp the fingers up so that they’re nearly immobile.
I have nice feet, too. It comes from years of wearing combat boots instead of high heels.