The controls felt like a Citation CJ, but the numbers on the new Collins Pro Line 21 displays didn’t belong to any CJ I had ever flown. Level at 45,000 feet, the true airspeed was 425 knots. And it had taken only 23 minutes to reach that rarified altitude after a near-maximum weight takeoff. How had Cessna’s entry-level light jet grown into such a performer? Well, it took about 17 years and four big steps to grow the original CitationJet into the CJ4 I was flying.
In the early 1990s, the cost of the Pratt & Whitney JT15 engine that powered the light Citations had increased to the point that the company could no longer continue to build its Citation 501 entry-level airplane at a price that made sense. But then Williams International entered the market with its all-new FJ44 series of turbofan engines with thrust ratings and prices well-suited for entry-level jets.
