Apollos Most Critical Rocket Engine

Of all the rocket engines used during the Apollo program, just one was considered to be critical to the whole operation, this was the lunar module ascent engine, if that didn't start or had a problem whilst on the moon then there was no way to rescue the crew, so it had to work with 100% reliability. This video looks at why this was so critical and the issues surrounding the use of its super dangerous hypergolic fuel.