Complex sentence: Gyroscopes failed on several occasions on the Hubble Space Telescope and had to be replaced several times, however, these were a different design called a gas-bearing gyroscope which do have certain benefits but as mentioned did experience some long-term reliability issues.
Split into simpler sentences: Gyroscopes failed on several occasions on the Hubble Space Telescope and had to be replaced several times. However, these were a different design called a gas-bearing gyroscope, which have certain benefits, but experienced some long-term reliability issues.