  In symbiotic binaries, jets and disk winds may be integral to the physics of
accretion onto white dwarfs from cool giants. The persistent outflow from
symbiotic star MWC 560 (=V694 Mon) is known to manifest as broad absorption
lines (BALs), most prominently at the Balmer transitions. We report the
detection of high-ionization BALs from C IV, Si IV, N V, and He II in
International Ultraviolet Explorer spectra obtained on 1990 April 29-30, when
an optical outburst temporarily erased the obscuring 'iron curtain' of
absorption troughs from Fe II and similar ions. The C IV and Si IV BALs reached
maximum radial velocities at least 1000 km/s higher than contemporaneous Mg II
and He II BALs; the same behaviors occur in the winds of quasars and
cataclysmic variables. An iron curtain lifts to unveil high-ionization BALs
during the P Cygni phase observed in some novae, suggesting by analogy a
temporary switch in MWC 560 from persistent outflow to discrete mass ejection.
At least three more symbiotic stars exhibit broad absorption with blue edges
faster than 1500 km/s; high-ionization BALs have been reported in AS 304
(=V4018 Sgr), while transient Balmer BALs have been reported in Z And and CH
Cyg. These BAL-producing fast outflows can have wider opening angles than has
been previously supposed. BAL symbiotics are short-timescale laboratories for
their giga-scale analogs, broad absorption line quasars (BALQSOs), which
display a similarly wide range of ionization states in their winds.
