So a Fair time after the E-20 SPC II experimamtal SSTO, and after Significant Nanotechnological Leaps, the E-20 SPC III was completed. Several Issues from the last one were addressed. For example the Rocket system was toned down significantly and merged into the fuselage. Another issue I did not see was the effects of Droo's Oxygen rich atmosphere on the ArcLight Reactors below the wings. On SPK-173 (My home planet), it contains 0.02% Oxygen, on Droo however, it was a staggering 20.95%. This in turn absolutely Destroys the reactors, reducing their lifetime from 10 Millennia down to just 100 years. to compensate, Each Reactor has been Sealed in their own Vacuum chamber to avoid any oxygen from getting in. Additional fixed issues include:
-Added weight to fix AeroCore instabilities
-Simplified Combustion systems
-SMT Control System switched to FSC Control

Notes:
-This aircraft still has incredibly powerful engines for its size and weight
-Speed above Mach 10 are possible at sea level

ENJOY