When I bought my David Williams flute from Ralph Sweet, he gave me a fingering chart that seems to be photocopied from a 19th century flute manual (should e-mail him and ask). At any rate, it shows the e-flat key held open for many of the notes in all three octaves. None of my Irish flute resources (Larsen, Vallely and some of the charts on the web) discuss this option. Does anybody do it? Is it a classical vs Irish thing? A just intonation vs equal temperment thing? A 19th century flute vs 20th century improved thing? I seem to remember keeping that key open most of the time on my Boehm, but of course that’s a whole different animal. Observations would be most welcome. I currently find that my pinky nestles comfortably between the e flat and c/c# keys, but if I need to change that I rather do it sooner than later before I get into bad habits.
Carefull there Kate…
The Irish flute was classical before it became Irish! 
Most Irish flutes have been modified to use whistle fingering, rather than the 19th c. classical fingerings. While venting the Eb key can improve the strenght of the note, most Irish flutes are designed to for the E to be in tune without the extra venting–so venting the Eb key will usually drive it a bit sharp. It’s also somewhat cumbersome to consistently vent the Eb key while playing dance tunes. I rest my pink on the key block, so out of the way (while remaining a solid anchor point) but easy to slip onto the the key when necessary.
Tintin pretty much covered it - it’s an old vs. modern flute thing. Using Ralph’s chart, some of those old flutes which folks swear are out of tune suddely are in tune. However, I do think venting is needed for a few notes when you move up into the third octave to torment your friends and family…
Eric
On most of the notes in the first two octaves on my keyed flutes, venting the E-flat key doesn’t really make much difference as to pitch or timbre.
Sometimes I vent, sometimes not.
One thing, though, to watch out for is that you don’t want to vent the E…it will drive that note very sharp.
Otherwise, I really haven’t found it makes much difference, other than sometimes it can help to steady the flute.
–James
At a flute workshop last year, Niall Keegan really pushed everyone to vent most notes with the eflat key. It’s almost essential for the higher octave - at least on my old flutes, can’t speak for modern wooden flutes as I don’t have one.
Many traditional players regard venting with the Eb key as an unnecessary refinement. I only do it when I want to strengthen the E (which is very rare in my case, really just when the last tune in a set ends on an E and I want it to sound a bit more robust, and even then I don’t bother except if I think of it!). If I vent the E on my flute it sounds almost as strong and reedy as the bottom D, although it also becomes much more sharp so I have to lip down at the same time. I don’t notice any effect on the other notes when I open that key so I don’t bother. But some good players vent everything above D with the Eb key.
On my 19th cent flute venting the Eb key raises the ptich
of the Fsharp, which tends to play flat. I think this may be
a slight issue on some recent flutes, too, so, if one’s Fsharp
is flat, the Eb key may help. But also one may be able to sharpen it
by venting one of the Fnatural keys.
Otherwise I don’t think one has to worry about the Eb key.
the foot of my R&R has 3 pewter plugs, to me that suggests that the Eb key was supposed to be open most of the time, of coarse i don’t bother with it, in fact, i have developed this nasty habit of resting my right hand ring finger very close the the D hole, shading it a bit.
eilam.
Thanks billions and billions! You guys just managed to fix the intonation problems on my old dead german. This is the kind of thing that makes me love this board.
'Course, I feel like an idiot for using the wrong fingerings for that flute all this time.
We need a Smiley of someone smacking themselves in the noggin with a flute.