In the Vandersteen comic strip Operatie Spacefighter, Len Curtis was the test pilot of the second F-42 Spacefighter prototype. Like the first prototype, Len's aircraft also departed from safe flight and crashed into the sea. Fortunately, Len was able to eject safely. While in hospital, Len told Colonel Raymond and Biggles that his ailerons had jammed.
Len was discharged from hospital a few days later but as he was leaving the hospital, two men confronted him but fled when Phillys, Len's fiancee, who was waiting nearby, ran up to help. Len would not say more to Phillys about the attack other than that it was a random attack by street thugs. He maintained this story when questioned by Raymond the next day.
Biggles and Phillys suspected that Len was hiding something and they were right. Len was later brought by two men to see nightclub owner Stanley, who demanded that he pay up his gambling debts. Stanley's men were about to beat him up when a receptionist brought in an anonymous note with some money: it was a gift for Len, provided he would mislead the authorities about the true location of the Spacefighter crash. Len paid off his debt but got violent, leading Stanley's men to drag him off, knock him out and dump him unconscious in a derelict industrial area.
Biggles had followed Len by means of a tracker which he had inserted into Len's cap. He rescued Len and brought him to hospital. There Len confessed the full facts and gave Biggles the true location of the wreck, allowing Biggles to plan a trap for whoever had sabotaged the Spacefighter.