As title. Some web pages claim that it can play 3 octaves, but I don’t think so.
Both whistles and flutes can have a range of 3 octaves, yes, but the fingering changes. Check the tinwhistle fingering research center, linked from the front page of chiff & fipple, and you’ll find that the 3rd octave fingering is peculiar (Finger G for D, A for E, B for F#, with other fingers down for stabalizing the note, and it gets weirder from there…)
Six-hole (Bb military style) fifes are typically played in the second & third octaves with the first ignored, six-hole flutes and whistles are typically played in the first two octaves with the third ignored.
Generally, the ‘unused’ octaves are out of tune, but this is a choice of the maker, and tuning adjustments can be made to allow 3 octaves that are reasonably in tune with each other. This is more often done with flutes, but can be done with whistles.
Boehm system flutes acheived, with basically the same principles as simple flutes and whistles, 4 and a half octaves; I don’t know what an expert player can get out of a modern boehm-derived flute, since my interest in flute history stops around the development of the boehm flute (at least, until they start writing books about ‘old system’ flutes made after the invention of the boehm flute…)
If your instrument was not designed with a 3rd octave in mind, you’ll have to experiment with the various possible fingerings, and try to blow it into tune from something near correct… but it -can- happen. (I don’t try it, but then, I only play high whistle and D-flute - the high whistle you don’t -want- to hear in the third octave, and the flute I don’t have the breath or focus of embouchure for testing the third octave yet.)
–Chris