  The discovery of the GRB-supernova association poses the question on the
nature of the inner engine as the outcome of Type Ib/c supernovae. These events
are believed to represent core-collapse of massive stars, probably in
low-period stellar binaries and similar but not identical to the Type II event
SN1987A. The branching ratio of Type Ib/c supernovae into GRB-supernovae has
the remarkably small value of less than 0.5%. These observational constraints
point towards a rapidly rotating black hole formed at low probability with low
kick velocity. The putative black hole hereby remains centered, and matures
into a high-mass object with large rotational energy in angular momentum. As
the MeV-neutrino emissions from SN1987A demonstrate, the most powerful probe of
the inner workings of core-collapse events are radiation channels to which the
remnant envelope is optically thin. We here discuss the prospect of
gravitational-wave emissions powered by a rapidly rotating central black hole
which, in contrast to MeV-neutrinos, can be probed to distances as large as
100Mpc through upcoming gravitational-wave detectors LIGO and Virgo. We
identify the GRB-emissions, commonly attributed to ultrarelativistic
baryon-poor ejecta, with a new process of linear acceleration of charged
particles along the axis of rotation of a black hole in response to spin-orbit
coupling. We include some preliminary numerical simulations on internal shocks
produced by intermittent ejecta. The results showing a radial splash, which
points towards low-luminosity and lower-energy radiation at large angles,
possibly related to X-ray flashes.
