The Birth Of The CJ

The Birth Of The CJ

The Birth Of The CJ

It’s hard to believe that the now-iconic Cessna CitationJet, a.k.a. the Model 525, was only a concept a bit over 25 years ago. As I’ve often said, time flies when you’re having fun. I well recall attending the CJ’s first-flight party on April 29, 1991 in Wichita, Kansas; despite an on-going downturn in general aviation’s fortunes in the 1980s, business jet sales continued to be healthy, and Cessna was anxious to cement its position as the #1 purveyor of light jets. The aviation press and early CJ customers were invited to witness the first liftoff of the new generation of Citations.

While waiting on the weather to clear, first-flight attendees viewed the prototype in the hangar.
While waiting on the weather to clear, first-flight attendees viewed the prototype in the hangar.

So, on the chosen morning, it was with great anticipation that about 400 of Cessna’s closest friends in the industry crowded around the prototype in typical late-spring weather for Wichita – meaning, it wasn’t the best for flying a brand-new aircraft. CEO Russ Meyer and Senior Marketing V.P. Roy Norris addressed the gathering, extolling the virtues of the new aircraft. Meanwhile, it rained, it blew and the ceiling hung low over the Air Capital – hardly the weather P.R. director Dean Humphrey had ordered for the event. Contingency after contingency was employed, to keep the crowd entertained while waiting on the weather. We enjoyed interminable plant tours and briefings, hastily inverted after the scheduled 9 a.m. lift-off didn’t happen, and luncheon was eventually served to keep the hungry hounds of the press at bay.

Engineering vice-president Milt Sills, who had piloted the original Citation on its first flight, had wanted a 10,000-foot ceiling so the initial hop could be made entirely under VFR, but at noon we were still waiting for a break. The wind increased to 40 mph, a mere Wichita zephyr, but beyond the established crosswind standards for a first flight.

Harking back a couple of decades, the first Citation also ran into weather delays on its initial flight. Similarly scheduled for 9 a.m., that flight finally took the air at 3:20 p.m., from the very same runway that was being used for the CitationJet’s first flight, almost 22 years later.

A Fresh Start

The CitationJet was breaking new ground, in an old, established way. The concept was to take the proven features of the Citation 500, first flown in September, 1969, and update it with the latest aerodynamic and propulsion technology. Attending the first-flight ceremonies was Dr. Sam Williams of Williams International, whose little FJ44 fanjet engine had evolved from Williams’ earlier experience with cruise-missile powerplants to become a powerful, yet parsimonious, business-jet engine. Williams International, in fact, was to receive the first production example of the CitationJet. Officially, the FJ44 was a Williams-Rolls, developed in partnership with Rolls-Royce.

Leveraging the Williams engine’s improved fuel specifics over the Pratt & Whitney JT-15D, Cessna went with a natural laminar-flow airfoil on an extended-span wing, 18 inches longer than the earlier Citation’s wing. A T-tail design replaced the old high-dihedral cruciform tail. Even with 6,000-pounds less total thrust than the 500, the CJ was to cruise 30 knots faster, range 10% farther and burn 19% less fuel, partly because it weighed 850 pounds less than its predecessor.

At the time of the first flight, the FJ44 engine had accumulated nearly 400 flight test hours, much it on the left pylon of a Citation 500 test-bed airplane. Most great advances in aircraft design result from employment of new propulsion technology; the Williams engines were to prove this theorem once again. Its 3.25:1 bypass ratio, using an efficient compressor system, cut fuel flow significantly while delivering adequate thrust for the lighter CJ. It also enabled cost savings to make the aircraft price competitive at $2,500,000 in 1988 dollars.

N525CJ, the CitationJet prototype, waits for its first flight, with test boom attached to the nose.
N525CJ, the CitationJet prototype, waits for its first flight, with test boom attached to the nose.

With careful manufacturing, the CJ’s natural laminar-flow wing could maintain its NLF back to the main spar, roughly 30% chord, using a chemical milling process in its skin and spar construction. By locating the fuselage tube atop the wing, a 57-inch cabin height could be achieved with a dropped aisle, and less drag resulted with the well-faired underslung wing. And with the lowered fuel tankage there was room in the wing for trailing-link maingear, forever banishing the “gotcha” touchdown of the stiff-legged Citation. Thrust attenuation paddles, much like those on Cessna’s T-37 trainer, were used to reduce the effect of residual thrust at idle, and an automatic deployment of the 35-degree landing flaps to 65 degrees after touchdown would reduce landing distance to 2,800 feet.

As with the Citation 500, the CitationJet was certificated under FAR Part 23, but was designed to the more-rigorous provisions of Part 25 transport airplane certification. At least, by the time the CJ arrived, single-pilot certification had become routine for Citations. The standard avionics package would be considered primitive 25 years later: the CJ featured Bendix/King panel-mounted equipment, including a KLN88 Loran C receiver, with a two-tube CRT EFIS.

Meanwhile, The Delays Continued

Milton Sills, Vice President of Engineering, explained the development and features of the new CitationJet.
Milton Sills, Vice President of Engineering, explained the development and features of the new CitationJet.

Many in the waiting assembly on first-flight day had airline connections to catch and had already surrendered their hotel rooms at the airport Marriot, having arrived the previous day in anticipation of a morning launch for the first flight. After lunch, the ominous weather showed little sign of abating, so the crowd was reluctantly dismissed. That was, of course, the opportunity the meteorological spirits had been waiting for; by late afternoon, the requisite breaks appeared in the overcast and the drizzle dried up. At 5:35 p.m., test pilots Bob Leonard and Bob Carnahan lifted off in N525CJ for a quick hop up to 10,000 feet, out to the Cheney test area west of Wichita, where they would check handling and trim, engine response, gear and flap extensions, speed brake effectiveness and an approach to a stall, keeping the IAS down to 180 knots. As expected, all went well; a Citation V flew chase during the flight, just in case.

Roy Norris, Vice President of Marketing, predicted a bright future for the Model 525.
Roy Norris, Vice President of Marketing, predicted a bright future for the Model 525.

According to my report of the post-landing proceedings, “Completing the atmosphere of déjà vu, the CitationJet received a blanket of winner’s-circle roses across its nose, repeating a ceremony performed in 1969 when the Model 500 made its first hop under the name of Calumet Farm’s famous Kentucky Derby winning racehorse.” Obviously, I was getting paid by the word to wax eloquent. Actually, the magnificent Citation won the Triple Crown in 1948, not just the Derby.

At the CitationJet’s first-flight ceremony, Roy H. Norris predicted 1,000 CJ’s would be sold during the first ten years of production. He wasn’t far off the mark, thanks to the introduction of the CJ2 and its follow-on brethren. Some 359 of the original CitationJets were delivered before it was replaced by the CJ1, and eventually over 700 525s were built through 2011. Today, the straight 525 lives on as the M2. The CitationJet’s difficult first flight turned out to be an entry into a highly-successful pro-duction life.

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