That year, he began working for KLM Royal Dutch Airlines as a flight director, and in 1951, he commenced duty as a first officer on the Douglas DC-3.

Jan Bartelski, a KLM captain until 1978 and later president of the International Federation of Air Line Pilots' Associations, was a contemporary of Veldhuyzen van Zanten and knew him personally.

[3] When the news of the Tenerife disaster broke, the KLM executives looked for Veldhuyzen van Zanten to aid their investigation team, only to realize that he was the captain of the flight involved in the accident and had died in it.

The KLM's flight crew had been aware of the Pan Am behind them, but believed that it had already cleared the runway due to abnormal call signs being used by the control tower to identify PAM 1736.

Standard procedure aboard flights at the time had copilots defer to senior pilots regarding conflicting judgment calls (this was changed following the disaster).

And the Control Tower believed that the KLM 747 remained stationary on the runway as instructed, but could not confirm visually due to dense fog in the area.