  We present the first in-depth statistical survey of flare source heights
observed by RHESSI. Flares were found using a flare-finding algorithm designed
to search the 6-10 keV count-rate when RHESSI's full sensitivity was available
in order to find the smallest events (Christe et al., 2008). Between March 2002
and March 2007, a total of 25,006 events were found. Source locations were
determined in the 4-10 keV, 10-15 keV, and 15-30 keV energy ranges for each
event. In order to extract the height distribution from the observed projected
source positions, a forward-fit model was developed with an assumed source
height distribution where height is measured from the photosphere. We find that
the best flare height distribution is given by g(h) \propto exp(-h/{\lambda})
where {\lambda} = 6.1\pm0.3 Mm is the scale height. A power-law height
distribution with a negative power-law index, {\gamma} = 3.1 \pm 0.1 is also
consistent with the data. Interpreted as thermal loop top sources, these
heights are compared to loops generated by a potential field model (PFSS). The
measured flare heights distribution are found to be much steeper than the
potential field loop height distribution which may be a signature of the flare
energization process.
