I can reach the second octave now, pretty consistently, but when I try to sustain a high note, I often get a stacatto or morse code sounding series of notes instead of a smooth, single note. What is going on and how do I fix it?
Stop flappin’ your lips 
From your description, it sounds as if your lips are not strong enough yet to maintain the narrow embouchure and breath support you need for the higher notes, and you’re interrupting the airflow. Are you feeling fatigue or strain around the mouth while playing these? You could try working on lower octave harmonics, ie: finger & blow a low D, tighten your embouchure and pop into the higher D and the other intervals beyond.
To quote Denny: Have we trotted out the bunny nose wrinkle yet? 
Bob
Some previous threads that might have a gem (or “Jem”) or two for you to ponder:
Embouchure for beginner - suggestions to reduce air needed?
https://forums.chiffandfipple.com/t/embouchure-for-beginner-suggestions-to-reduce-air-needed/77698/1
Pointing in the right direction
https://forums.chiffandfipple.com/t/pointing-in-the-right-direction/62272/1
particularly Jem’s post (white space added, for, ahem, readability):
Patience is a principal virtue here. It takes time to develop the strength to play the tone you’re after.
As I think I’ve mentioned, one way that helps is to buy a higher pitched flute, e.g. a Sweetheart G or A,
and play tunes on it. In any case, patient practice… Think months.
Maybe you’re blowing too hard? You shouldn’t be blowing harder in the second octave than the first. Is your jaw mobile when you’re playing?
Helpful stuff. Thanks.
I don’t know what you mean by “mobile”. I can push my lower lip out, which sometimes helps me get into the second octave. Occasionally, I’ll get a position where the lower octave is booming, but then it’s even harder to jump octaves. I’m still inconsistent when it comes to getting a strong lower octave sound.
The upper octave sounds like the air is skipping off the hole a little sometimes. I’m working on some of those exercises. I don’t mind going slowly, but I want to be going slowly in the right direction, rather than poking around and going nowhere, which is how I feel a lot of the time. If I could figure out some perfect placement where I could always get a really strong bottom and then work my way up, that would be great, but I still feel that the strong first octave is a mysterious visitor who comes and goes as he wishes, leaving me perplexed as to how he got there and how to get him back again. And then I wonder if he was even there at all…
There is no magic bullet and the prospect that you are doing something wrong is remote.
Do long tones, do exercises, if you feel you need moral support, write to us,
but above all, give it three more months.
Well put. I totally understand. Both upper and lower.
Personally, I’m dubious about anyone on a forum like this (in contrast to a teacher who can look at what you’re doing, and even then I’m very skeptical!) offering a lot of hints that will prove really helpful. Maybe because I was mostly self-taught? But in any case, persistence is the key. If you want it badly enough, and I read through your lines that you have committment, it really will come in time. If you’re like me, you’ll never fully understand from whence or exactly how. Initially it will be there at times and then lost as you said. Later it will come more often; then with a little feeble consistency; then finally without any effort or thought, mostly like breathing. (Yeah, you’ll still have “bad tone” hours.)
But explain it to anyone else? Hopeless.
Hang in there - you will arrive in time, and everyone else has had to go through the same mysteries.
Best of luck to you friend,
- Bill
I am reminded of a phrase I came across recently when reading about flute embouchure: “This coordination is not intuitive and requires assimilation through training” . I think it meant us training our lips and lungs, not us being trained.
In short, we’ve been through this too, and written such posts to this forum, some of us.
I was told ‘Learning to play flute is not for the faint of heart,’ which certainly has proved true.
Par for the course, you are.
Sometimes I’ve found it helpful to work from “bad” as a starting point. As you’re having these problems, pay attention to what you’re doing. Take note of them (write them down, even!) Then try changing one thing at a time to see what improves the situation somewhat.
My guess would be that perhaps your embouchure is a little too tight! You could be pulling the corners of your mouth back to the extreme. Try making more of a “pout.” You want the airjet to be small, but you also want it to be basically round or slightly oval, not elliptical.
Another (and very undesirable) possibility is that you’re falling victim to the dreaded throat-vibrato – if that Morse Code is coming from the back of your mouth or your throat, then you’ve managed to tighten up all the muscles there and that’s NOT a good thing to be practicing.
Why not go see a local flute teacher for a lesson or two? The fundamentals of a good embouchure translate across all styles of flutes and fluteplaying.
There was a flute workshop near here that I thought of going to, but when I asked my wife, she asked me if I wanted to be “kicked in the nuts” (her words). I did not, so the flute workshop is out. Paid lessons are more or less out as well. I’m pretty much on my own here. Again, I don’t mind. From what I can tell, I’ll figure it out eventually. I just want to keep making progress, even if it’s slow. Eventually, my wife might let me go to a workshop, once the baby is out of college. Who knows?
Time put in is time well spent, and we all go through the phase of not being able to get a consistent embouchure. It has to become stronger on its own, just by repetition, and it will be there when you put enough time in to make it strong. Yes, you have to have the proper form to get the best tone, etc, but it all comes in with practice, and trial and failure, and then success.
The only thing I can add as a suggestion, that worked wonders for me, is to use the standard fingertip hold on the top holes (if you aren’t already), and for me-piper’s grip on the bottom. Until I went with the standard hold on top, the embouchure hole would move around on me, and consistency was sporadic until I adopted standard fingertip hold on top.
Yes, to the teacher thing-if you can get some lessons, all the better. Above all, it’s not instantaneous, it’s a process. Some take more time than others, but you will know when you get there. So, don’t sweat it, it all comes together in time. Just hang in there, and give it more time and practice. No need to worry, or trying to get an instant fix. Patience is your friend, and you need some of that to get through it. Just practice, and take it as it comes-but relax, and play with as little tension that you can manage, in your face and fingers. Others have said as much-just sort out the details in the posts provided.
Oh yeah, and have fun!!! That’s more important in the long run, and hard to get without the passion of just playing for the sake of the pleasure it brings. I’m sure some are better at that than others, but I think it’s a pretty important point on which to base your efforts.
Have a blast! 
For what its worth. . . .it doesn’t sound like you are far enough along to need a full fledged workshop, particularly if economics is a consideration. Keep hanging around any musical gatherings (Irish Sessions if possible) and you will stumble on a fluter. Just a few moments may serve to get you sorted and on your way.
I’m not a great fan of jumping to the upper octave right away, but I can’t stop you. . .Cathy has pointed out that there are some hazards to avoid. If you continue along the DIY path, you might consider acquiring another instrument or two to switch off and use this to train your embouchure. Curiously,the Yamaha Fife, generally under $10, has a larger tonehole than some of Doug’s flutes. I’m not a great fan of the “Reform Style Lip-plate”, the kind with little wings, but it may help you on your journey. Years ago I saw aluminum cylindrical ‘G’ flutes for under $20 through a “World Music” shop. I"m not really trying to stoke your FLOAD, but. . .
Embouchure training and strength do not come over night. I often wonder if Kevin Crawford can do pushups with those lips!
Jack Coen told a marvelous story of starting in a fife band as a boy, and thinking something wrong with his instrument because he didn’t have the upper octave on his fife. . .!
Bob
OK, a couple of belated thoughts for ya.
Occasionally play in front of a mirror. When things are working relatively well, pay careful attention to details like the angle of the flute to your mouth (mouths differ so might not be exaclty horizontal), position of bottom lip to back of embouchure hole, shape of lips and relation to front of embouchure hole. Also how you’re supporting the flute.
Try to commit the appearance of these details to memory - not as a “forever” template, but as a temporary touchstone. When things aren’t working, go back to the mirror and see what has changed. Oh, and if things are working much better than expected, look in the mirror again and memorize that!
This helped me a good deal and still does occasionally - I fall into some lazy bad posture habit and don’t realize it by feel, only by looking. May or may not be helpful to you, but for what it’s worth.
This is probably something you know and really obvious, but for tone and the number of bars you can play on one breath, the key is “focus”. When the breath stream is focussed correctly you have both the potential of power and duration. There’s a real temptation to blow harder when it sounds weak. Don’t do that. Won’t fix anything. It’s all a matter of focussed airstream.
Also, playing the second octave and above isn’t about blowing harder. That works with whistle, but not with flute. You can keep the force behind the airstream constant or even back off a bit (mostly what I do) when going up an octave. What changes is the shape of the lips, probably a narrowing of aperture, and how it’s aimed. I can’t tell you how to do it - it’s all muscle memory with me. You’ll figure it out and then be in the spot of not being able to tell anyone either, probably.
About flute holds etc. You can go on YouTube and watch amazingly accomplished fluters using all sort of grips and body positions, some of which make me wince just to watch. Works for them, but some of the extreme ones may lead to physical problems later - if not for them, maybe for you. Listen to your body. Erect posture, relaxed shoulders, no extreme twisting is probably best. If you want to adopt piper’s grip on one or both hands, fine…but be aware that it will require a lot of re-adjustment if you ever decide to play a keyed flute later on and really use those keys to play in different musical keys than those common to Irish tunes. On the other hand, or both, the piper’s grip has its advantages in a limited context. Have to weigh the tradeoffs.
Good luck, and sorry for the length.
- Bill
“Length”? 
Jennifer Cluff has some wonderful lessons on YouTube. She is a Boehm flute player but does a great job explaining the “newer” “loose and forward” embouchure that creates the best tone & control on pretty much any flute. When you start paying attention to your favorite-sounding flute players you’ll start noticing some similarities.
http://www.youtube.com/watch?v=7HWWQpueRvY
BUT FOR STARTERS … take a look at these:
http://www.youtube.com/watch?v=mCYOHShLAeY
http://www.youtube.com/watch?v=h6eFbtc0w2A
They are as basic as it gets but they cover all the stuff every flute player should know, even if we don’t necessarily practice. If you were a student of mine I’d confine you to the material in these three videos for a month of daily practice and prescribe some of the exercises as daily requirements thereafter. Good luck, and don’t work too hard – work smart!!
In another thread, Steve recently mentioned the one handed scale. What a great focus exercise, for both 8ves! I now use to do it a couple of times when I pick up the flute, and also when I’m losing focus… it summons that “mysterious visitor” back quite reliably.