Hubble took ~12 years from initial funding to launch with the challenger disaster postponing it 4 years out of that. Additionally if the decision was made to us

Hubble took ~12 years from initial funding to launch with the challenger disaster postponing it 4 years out of that. Additionally if the decision was made to use traditional mirror techniques the Hubble was predicted to launch in 5 years already, instead of the difficulty they found with the alternative method but they didn't know that at the outset.