The development and early years of a legendary aircraft.
The Cessna Caravan business turboprop aircraft seems like it’s been around forever- but surprisingly- it’s only 33 years since the first aircraft rolled off Wichita’s production line in August 1984. Now this multi-role aircraft- which operates in 68 countries around the world- has become indispensable. It was conceived at just the right time and has never looked back since that first Federal Express order. In fact, as of this writing- aircraft number 1-522 had just rolled off the Wichita production line.
The latest statistics from Cessna reveal the world Caravan fleet flight time has risen to approximately 8.4 million hours- and is notching up 71-000 flight hours per month. Indeed- the largest single Caravan operator- Federal Express- is recording a dispatch reliability of 99%.
Not bad for an aircraft that was originally built for bush-flying- and which- has since blossomed into a rugged multi-task landplane and amphibian.
Caravans are utilized by owner/pilots; shuttle scheduled passengers on short inter-island hops; to take people sightseeing, and to defend home shores through Government agencies and air-arms; among many other things. They are magnificent haulers and some carry the strangest cargos.
In short, the Caravan has come of age. Cheers and happy 21st birthday to Cessna’s Caravan.
Perhaps one of the strangest Caravan operations is based in Europe- where Peter Wood is very proud of his Grand Caravan: ‘We fly more passengers than British Airways – forty million a year in fact and none have ever complained.’
Mr. Wood’s U.K. company is Glass Eels Ltd and his aircraft – which replaced three trucks – is aptly registered G-EELS. Have you guessed yet? His company has been catching and distributing these delicacies since 1970- and used to transport the live Glass Eels by road. In 1997 the company bought a Cessna Grand Caravan and now distributes them throughout Europe by air. The season runs from October through May and through the worst of Europe’s winters. When not on eel duties the aircraft is leased out.
The company collects the slippery customers from France- Spain and Portugal and then flies them to Greece- Holland- Germany- Poland- Denmark and even western Russia. Mr. Wood’s aircraft has logged about 500 hours annually since 1997. ‘Aircraft reliability has been great; we’ve never had to scrub a flight because of an aircraft un-serviceability in 3-000 hours flying duties-‘ he confirmed.
Back to its roots…
So how did this universal hauler come into being? The designation Cessna Caravan 208 gives a clue to Cessna’s general aviation chronology. Before the ’208 came Cessna 206 single piston aircraft and Cessna 207 families of six and seven seat high wing single engine aircraft- which were developed from the legendary Skywagon and turbo-charged Skywagon utility aircraft. Both Skywagon models grew into hotter turbo-charged versions- eventually becoming known as the Turbo Stationair 206 and Turbo Stationair 207. The standard cargo/utility Stationair 206 was fitted with double loading doors and was powered by a Continental 310 hp TSIO-520-M turbocharged engine- as was the slightly stretched ’207 version. Then in early 1982 Cessna engineers widened and stretched a Stationair 206 fuselage to create a mock-up – the beginning of the ’208.
‘We ended up lengthening the mock-up in order to haul what our customers wanted – 55 gallon fuel drums and four feet by eight feet sheets of plywood.’ said Phil Hedrick- Cessna Caravan vice president- engineering (1981-1986). ‘The primary limitation was the size of the cargo door- so we made it huge. In less than one year we went from program go-ahead to first flight. That was unheard-of at the time- and it still is.’
Marketing surveys from the late seventies concluded that a modern- large capacity- rugged single engine aircraft could compete successfully with both older single- and some twin-engined aircraft operating in this theater. Several old designs needed replacement; especially aircraft types such as De Havilland Canada Otters- Beavers and Beech 18s- which were the backbone of Alaskan and Canadian bush operators.
This market alone was predicted to be worth 35-45 new aircraft per year to the successful candidate. In addition to meeting the market demands- the minds at Cessna decided early on that the new design would be more adaptable if it incorporated a conversion for float and ski operations.
Thus Cessna’s new offering was going to be a utility aircraft to serve the remote areas of the world. It was certainly not envisioned to be a package hauler- or a corporate machine.
Building a workhorse
The growing scarcity of 80 and 100 octane aviation fuel was also a major factor in getting bush-pilots- in particular- to start thinking in terms of re-investing in the more expensive turboprops which ran on the readily available JP-4 and other kerosene based fuels. Key to Cessna’s clean sheet preliminary design was the revolutionary 600hp Pratt & Whitney Canada PT6A turboprop engine – it was big- promised to be proven safe- and was available.
Work got underway in 1981 in the hands of a group of advanced design and project engineers from Cessna’s Pawnee Division under the direction of chief engineer John Berwick. The design centered around a ten seat layout with a 62-inch-wide cabin which allowed three abreast seating and an aisle. A 50- by 49-inch cargo door- which was split horizontally- allowed passenger entry- cargo egress- and easy removal for the parachute role. Three additional doors were also conceived to cover multi-combinations to ease entry and exit for passengers and awkward shaped freight.
Performance goals included a cruise speed above 175 knots which was a real challenge given the fixed landing gear and the strut braced wings. A good short field performance was also of paramount importance- which dictated very large and effective wing flaps- while maintaining light plane stick forces in the absence of powered controls. Those at Cessna knew that this would be no mean feat- given that back in 1951 the company had built a large seven seat aircraft- known as the C-308- to compete with the De Havilland Canada’s Beaver- but it had proved to be unwieldy in roll response.
Cessna’s engineers also realized- early on- that when in service- the aircraft would probably be too large to fit existing hangars at small airports- and out in the boon-docks- hangars could be non-existent. So corrosion proofing was an early basic requirement for the Caravan.
Cessna engineers borrowed company anti-corrosion production techniques already employed on their crop-spraying C-188 Agwagons- to very good effect.
Take-off of the Caravan…
The first flight of the engineering prototype occurred on December 9- 1982. Cessna’s designers and engineers then waited for bush operators to queue at the door.
This they did- but surprisingly- the first big order came from overnight delivery specialist Federal Express Corporation who literally made the aircraft an ‘overnight’ success. Back in 1983 a Caravan appeared on the cover of Flying Magazine and was spotted by Federal Express Founder and CEO Fred Smith. In the following months, Cessna and FedEx worked together to define the overnight parcel company’s requirement.
Engineers added a composite belly cargo pod and increased the MTOW from 7-300 pounds to 8-000. Cessna’s Phil Hedrick said of this time- ‘Federal Express was instrumental in legitimizing the Caravan. The company really gave the aircraft credibility.’
Scott Bengston from Cessna’s Caravan Product Marketing Department explained- ‘FedEx were looking for a suitable aircraft to take over ground trucking operations. Right here in Kansas (Wichita)- some parts of the state are thinly populated and ground trucking was their only option before the Caravan came along. What the Caravan allowed them to do was to feed these outlying towns by air to the larger FedEx aircraft at the major cities.’
FedEx ordered 40 C208A Cargomasters- and incorporated many special freight-only features such as no cabin windows or starboard rear door. More cargo tie-downs were added and an additional cargo net. The now familiar under fuselage cargo pannier was added and made from composite materials. A six-inch vertical fin/rudder extension was designed-in- and the jet pipe was extended to deflect the exhaust clear of the pannier. The cockpit featured Honeywell avionics- and the aircraft’s MTOW certificated at 8-000 pounds.
The Cessna Grand Caravan 208 business turboprop airplanes gained FAA certification in October 1984 and the FedEx variant entered service in 1985. FedEx’s Cargomasters had the distinction of becoming the first single-engined aircraft to achieve FAA certification for ILS Cat II conditions.
‘We were just settling in with FedEx’s specifications for the (C208A) Cargomaster when they asked if we could make the aircraft larger-‘ said Hedrick. ‘We weren’t quite ready for that- but by October 1985- Cessna experimental engineers had successfully stretched the Caravan airframe to add 113 extra cubic feet of cargo hauling volume and 500-pounds more payload than the original.’ FedEx ordered 260 Super Cargomasters- and by 1986 Cessna was delivering them at the rate of three per month.
The Super Cargomaster included a four foot fuselage extension plug aft of the wing. The aircraft was certificated to carry a maximum payload of 3-500lbs in its 450 cu ft of cargo cabin and the cargo pod. By 1991 the 208B model was powered by a 675 shp P&WC PT6A-114A engine.
However- it was at the 1990 NBAA in Dallas- Texas- that a truly significant development came regarding the Caravan and business aviation. Join us next month as we pick up the story with the entry of the Grand Caravan.
More information from www.cessna.com