Category 1 is always the greatest level of hazard (that is, it is the most hazardous within that class). If Category 1 is further divided, Category 1A within the same hazard class is a greater hazard than category 1B. Category 2 within the same hazard class is more hazardous than category 3, and so on.
Correction: An earlier version of this story incorrectly stated that Charles Nungesser and Francois FranÃ§ois coli would have been the first pilots to make a nonstop transatlantic. Flight a pair Of british pilots made such a flight in. 1919
Far from being the first! 1  The very first transatlantic flight took place in 1919 (Lindbergh had absolutely nothing to do with it), when Lieutenant Commander Albert C. Read flew the Lame Duck, a Navy Curtiss NC-4 single-pilot flying boat for this purpose.