Blake Scholl

There's engine efficiency, something called thrust-specific fuel consumption.

Pounds of thrust, or sorry, pounds of fuel per pounds of thrust per hour.

How much fuel does it take to create a pound of thrust and sustain it for an hour?

Structural efficiency.

What percentage of my overall airplane weight is the empty weight of the airplane versus fuel versus people and cargo and payload?

And then last is speed.

Mach number.

If you have those four numbers and you've got the correct assumptions, you can set up a mission profile for an airplane and predict the entire performance of it.

Concorde's numbers were all published.

How much better than Concorde could we do?

All of that thinking it through from first principles mattered.

I think I mentioned earlier that one of the other ideas I looked at and didn't do was an airline.

Truth be told, I didn't actually have the courage to go double-click on supersonic first.

I thought, there's no way.

There's no way, but maybe an airline.

I built all the financial models for how an airline worked.

That turned out to be really useful because I understood airline economics.

When you go model out airline economics, the first thing you learn is the fill rate on the seats really matters.

A seat that flies empty just adds cost, but filling that seat versus it being empty is like free revenue.

The fill rate, they call it load factor, that really mattered.