We have demonstrated a fully engineered 5 Gb/s repeaterless long-span transmission system with an excellent long term performance. The transmitting power from an optical power booster was +15.5 dBm with SBS suppression and an optical preamplifier receiver provided a receiver sensitivity of -38 dBm for 10(-9) BER (or -35 dBm for 10(-15) BER). A Ti:LiNbO3 external modulator transmitter allowed dispersion limited repeaterless transmission through 226 km non-DSF (a total dispersion of 4100 ps/nm).