diff --git a/src/fraggle/fraggle_generate.f90 b/src/fraggle/fraggle_generate.f90
index 47e55e51a..ddb14c261 100644
--- a/src/fraggle/fraggle_generate.f90
+++ b/src/fraggle/fraggle_generate.f90
@@ -589,7 +589,7 @@ module subroutine fraggle_generate_vel_vec(collider, nbody_system, param, lfailu
                ! We didn't converge. Reset the fragment positions and velocities and try a new configuration with some slightly different parameters
                ! Reduce the number of fragments by one
                nlast = fragments%nbody
-               fragments%Ip(:,1) = fragments%mass(1) * impactors%Ip(:,1) + fragments%mass(nlast) * impactors%Ip(:,nlast)
+               fragments%Ip(:,1) = fragments%mass(1) * fragments%Ip(:,1) + fragments%mass(nlast) * fragments%Ip(:,nlast)
                fragments%mass(1) = fragments%mass(1) + fragments%mass(nlast)
                fragments%Ip(:,1) = fragments%Ip(:,1) / fragments%mass(1)
                fragments%Gmass(1) = fragments%Gmass(1) + fragments%mass(nlast)
diff --git a/src/swiftest/swiftest_discard.f90 b/src/swiftest/swiftest_discard.f90
index 2b69012b7..01a83f5db 100644
--- a/src/swiftest/swiftest_discard.f90
+++ b/src/swiftest/swiftest_discard.f90
@@ -92,6 +92,8 @@ module subroutine swiftest_discard_tp(self, nbody_system, param)
       logical, dimension(:), allocatable :: ldiscard
       integer(I4B) :: npl, ntp
 
+      if (self%nbody == 0) return
+
       associate(tp => self, cb => nbody_system%cb, pl => nbody_system%pl)
          ntp = tp%nbody
          npl = pl%nbody