zip fuels
...that after spending a billion dollars developing borane-enriched "zip fuels" to power a new generation of jet engines, the US Air Force realized the entire idea was unworkable and had to abandon it all in 1959?
...that after spending a billion dollars developing <a href="./Borane" id="mwB_Y" rel="mw:WikiLink" title="Borane">borane</a>-enriched "<b id="mwB_c"><a href="./Zip_fuel" id="mwB_g" rel="mw:WikiLink" title="Zip fuel">zip fuels</a></b>" to power a new generation of <a href="./Jet_engine" id="mwB_k" rel="mw:WikiLink" title="Jet engine">jet engines</a>, the <a class="mw-redirect" href="./US_Air_Force" id="mwB_o" rel="mw:WikiLink" title="US Air Force">US Air Force</a> realized the entire idea was unworkable and had to abandon it all in 1959?