Drop properties during and after secondary breakup in the bag, multimo
de and shear breakup regimes were observed for shock-wave-initiated di
sturbances in air at normal temperature and pressure. Test liquids inc
luded water, n-heptane, ethyl alcohol and glycerol mixtures to yield W
eber numbers of 15-600, Ohnesorge numbers of 0.0025-0.039, liquid/gas
density ratios of 579-985 and Reynolds numbers of 1060-15080. Measurem
ents included pulsed shadowgraphy and double-pulsed holography to find
drop sizes and velocities after breakup. Drop size distributions afte
r breakup satisfied Simmons' universal root normal distribution in all
three breakup regimes, after removing the core (or drop-forming) drop
from the drop population for shear breakup. The size and velocity of
the core drop after shear breakup was correlated separately based on t
he observation that the end of drop stripping corresponded to a consta
nt Eotvos number. The relative velocities of the drop liquid were sign
ificantly reduced during secondary breakup, due both to the large drag
coefficients caused by drop deformation and the reduced relaxation ti
mes of smaller drops. These effects were correlated successfully based
on a simplified phenomenological theory.