Cessna 441 Conquest II Operations

Service kit SK 441-79 was made available for retrofit. The End of the Line There is some question about whether any 441’s were actually built in 1986 or whether they were actually inventory built in 1984 or 1985 and carried forward. More important is that Cessna had reached the end of the line for all turbo- prop products except for the single P&WC PT6 powered Caravan. In 1986, Cessna evaluated a follow-on, economy version of the 441, powered by PT6s. It was not a go then, nor did it pass muster with the dealer organization in the early 1990s when planners again proposed the program. Dealers thought the P&WC- powered version would be a step back- wards because, in the words of one, “it couldn’t climb, go as fast or as high as the Conquest II.” Despite fairly extensive service prob- lems with the AlliedSignal TPE331-8 engines, there have been only five ADs issued to date. Three—92-02-19, 93-02- 19, which superseded the previous AD, and 93-02-01—addressed fuel manifold problems. They all had very short com- pliance periods. The most recent, 95-16- 08, required an extensive review of records and mandatory engine disassem- bly if any major work had been done by Fliteline Maintenance of Wharton, Texas and two specifically named mechanics, or if any life-limited parts had been supplied by them. The most recent ADs are blanket ones, affecting many aircraft. AD 97-25-04, requires changes to the AFM to prohibit positioning the power levers below the flight idle stop in flight. Another directive affects operation in icing conditions (See Intelligence, April 1998, page 20.) According to one Conquest specialist, John Berizzi, business development man- ager at Executive Wings, Inc. of Lake- land, Fla., “AD searches on Conquests are fairly easy. We do a number of pre- buy inspections, and ADs and service bul- letins are not big issues. The main questions are whether the customer is getting a good airplane for the price.” Propulsion System The TPE331-8, rated at 636 shp, and developed for the CE-441, provided excellent performance for the price. FROM OCTOBER 1998 BUSINESS & COMMERCIAL AVIATION. © 1998, THE McGRAW-HILL COMPANIES, INC. ALL RIGHTS RESERVED. The CE-441 horizontal stabilizer (below) was designed with pronounced dihedral to minimize the effects of propeller whirl mode vibration, but failures required significant redesign. Right: The long nose provides generous baggage space and easy access. FROM OCTOBER 1998 BUSINESS & COMMERCIAL AVIATION. © 1998, THE McGRAW-HILL COMPANIES, INC. ALL RIGHTS RESERVED. However, reliability issues quickly arose. Fuel nozzle problems and maintenance requirements, carbon buildup in the com- bustor and performance deterioration in relatively few operating hours due to tur- bine blade erosion were among operator complaints. (See “Operator Survey,” November 1984, page 42).The -8 has short major service intervals—hot section inspections at 1,500-hour intervals and a 3,000-hour TBO. Operators have not liked the high cost of major maintenance, either. Executive Wings claims to be the pio- neer in upgrading the -8 for maintainabil- ity and reliability, obtaining two STCs in March 1991. The improvements devel- oped involve exchanging the -8 combus- tor and turbine with components developed for the TPE331-10 series. This change addresses another issue, since the -10 includes duplex, two-headed fuel nozzles. At first, the company called its mods the “Super 8 Engine Conver- sion.” It is now trademarked as the “Executive Five Eleven” conversion. HSI is extended to 2,500 hours; TBO is stretched to 5,000 hours. Among other advantages Executive Wings claims are reduction of HSI costs of from 30 to 50 percent, fuel nozzle maintenance costs cut by as much as 75 percent—from an average of $8 per hour to $2—and reduced turbine blade carbon erosion. The -10 first stage turbine wheels are air- cooled. They also are segmented and have replaceable blades. The modifica- tion can reduce 441 operating costs up to $155 per hour compared to a standard 441, according to Executive Wings. Berizzi says the initial objective of the conversion was to cut maintenance costs and improve reliability. The substantial performance improvement, including the ability to carry full power to FL 260, up from FL 220 in standard conditions, and an increase in cruise speed of from 25 KTAS to 30 KTAS, were bonuses, he O p e r a t i o n s Cockpit design of the Conquest II wins praise from pilots for good layout, generous space. Visibility is good. Original equipment ARC avionics, including analog ARC 1000 flight control system, are weak points. In typical executive configuration, the cabin can seat six in comfort. Noise and vibration levels, largely generated by propeller wash, and regulation of temperature are regular passenger complaints. B/CA Equipped Price $1,855,010 Bluebook, ’98 $1,520,000 Characteristics Seating 1 + 9/9 Wing Loading 32.8 Power Loading 7.9 Noise (EPNdB) 74.0 Dimensions (ft/m) External Length 39.0/11.9 Height 13.1/4.0 Span 49.3/15.0 Internal Length 12.9/3.9 Height 4.3/1.3 Width 4.6/1.4 Power Engines 2 ASE TPE331-8 Output 636 shp ea. TBO 3,000 Weights (lb/kg) Max Ramp 9.925/4,501 Max Takeoff 9,850/4,467 Max Landing 9,360/4,245 Zero Fuel 8,500/3,855 BOW 6,209/2,816 Max Payload 2,291/1,039 Useful Load 3,716/1,685 Executive Payload 1,600/726 Max Fuel 3,183/1,444 Payload/Max Fuel 533/242 Fuel/Max Payload 1,425/646 Fuel/Executive Payload 2,116/960 Limits MMO 0.55 VMO 243 PSI 6.3 Airport Performance (ft/m) TOFL (SL ISA) 2,465/1,118 TOFL (5,000 ft ISA+20°) 3,720/1,687 Cruise Long Range TAS 259 Fuel Flow 304 Altitude FL 350 Specific Range 0.85 High Speed TAS 293 Fuel Flow 510 Altitude FL 290 Specific Range 0.57 NBAA IFR Ranges (200-nm alternate) Max Payload Nautical Miles 1,566 Average Speed 299 Trip Fuel 280 nm/lb 0.66 Specifications Cessna Conquest II CE- 441 claims. In September 1997, Executive Wings was FAA approved as a TPE331 overhaul facility. The repair station license covers -1 through -11 series engines. West Star Aviation of Grand Junction, Colo. approached the -8 in a different way. The company teamed with AlliedSignal in 1992 and obtained an STC to install factory-modified TPE331- 10N engines on the Conquest II. Cus- tomer engines are removed at West Star and shipped to AlliedSignal’s Phoenix facility for modification and then returned to Grand Junction for installa- tion and final rigging. West Star’s conversion is trademarked as the Dash 10 and offers comparable benefits. Russ Williams, West Star’s vice president of business development, says time-to-climb to cruise altitude improves by eight to 10 percent, cruise speed increases an average of 25 knots and hourly total cost, including reserves, can be reduced by as much as 11 percent. Williams estimates DOCs range from $300 to $350 per hour depending on stage lengths, power settings and average fuel costs. The higher power output at altitude FROM OCTOBER 1998 BUSINESS & COMMERCIAL AVIATION. © 1998, THE McGRAW-HILL COMPANIES, INC. ALL RIGHTS RESERVED. ➤Propellers— Hartzell initially sup- plied the original equipment pro- pellers. According to West Star’s Williams, Cessna installed McCauley three-blade propellers with Serial Number 0196. Both are 90 inches in diameter. The Conquest’s long nose is an ef fective transmitter of noise and vibration generated by the props. Depending upon power selection, the noise can be more pronounced in the cabin than in the cockpit. Blade-tip ground clearance is 10.2 inches. Blade erosion from dust, debris and water is a concern, and so is the possibility of prop strikes when taxiing over uneven ground. Berizzi of Executive Wings says his company worked with Har tzell to develop four-blade propellers to replace the OEM three-blade units. Tip clearance is increased by 2 1/4 inches. Executive Wings claims an eight- to 10-dB noise reduction in the cabin, decreased takeoff roll (primari- ly because of faster acceleration from more propeller efficiency), a 400- to 500-fpm rate of climb improvement and a three- to five-knot cruise speed increase. The replacement propellers have a five-year or 3,000-hour TBO. McCauley has STCed a BlackMac four-blade conversion for the 441. As with the Hartzell replacement props, they can be installed on aircraft pow- ered by either an original -8 engine or the -10 conversion. They offer similar per formance and sound reduction improvements. Diameter is 88.0 inch- es, and McCauley notes that the four- blade conversion reduces flyover noise as well as cabin sound levels. Recommended TBO is the earlier of 4,000 hours or 72 calendar months. Either conversion is available from both Executive Wings and West Star Aviation. Executive is pricing the Hartzell propeller switch at $33,900 for aircraft with original McCauley propellers and $37,250 for aircraft with Har tzell props. Its conversion price for the McCauley BlackMac is $37,500. West Star’s price for either is $37,500. ➤Batteries— Original equipment batteries are two, 25.5 volt, 22 ampere-hour nickel cadmium units. Marathon Battery Products was the source until Cessna changed to SAFT America with Serial Number 0340. The batteries, called “half-height” by some also provide about half the cranking power of full-size nickel cad- mium batteries. Marathon has devel- oped a modification that drops the battery box base to permit installa- tion of full-size nickel cadmium units. There are lead acid battery conver- sions. Premier Air Center of East Alton, Ill., of fers one that costs $5,000, or about the cost of a nickel cadmium battery, according to Rick Micacek of Premier. It provides more cranking power and simplifies mainte- nance. This is important at an airport with marginal ser vice. Premier rec- ommends that operators replace lead acid batteries every two years. They cost approximately $800 each. Premier also offers stainless steel exhaust fairings to replace the origi- nal equipment over wing exhaust duct. Exhaust heat embrittles the sur- rounding fiber glass, which then begins to deteriorate, leaving no sup- port or attachment for the exhaust duct. The replacement ducts provide a metal-to-metal structure. ➤Other Operational Mods— Both Executive Wings and West Star Avia- tion offer a number of other modifica- tions. Executive has a reduced-drag wing tip mod ($5,900) that provides a slight cruise speed increase. The greatest advantage, according to Berizzi, is improved stability at alti- tude. It also reduces autopilot work- load. West Star Aviation offers a Rock- well Collins APS-65 retrofit, a digital flight control system and three-axis autopilot that adds a number of fea- tures to reduce pilot workload and increase passenger comfor t. Fea- tures include improved altitude prese- lect and hold, indicated airspeed and vertical speed hold, and half-bank and soft ride modes. It is certificated to Category II approach standards. West Star charges $124,500 to remove the ARC 1000 and install the APS-65. For an operator who is plan- ning to keep a 441, it can pay off economically and operationally. ➤Increase Weight Kit— Boundary Layer Research of Everett, Wash. has received an STC to add vortex gener- ators to flying surfaces. The kit per- mits an increase of ramp weight from 9,925 to 10,240 pounds; max takeoff from 9,850 to 10,165 pounds; and zero fuel weight from 8,500 to 8,815 pounds. Max landing weight remains at 9,360 pounds. Stall speeds increase by one knot at the higher weight: VS goes from 89 to 90 KIAS and V SO from 74 to 75 KIAS. Y MCA remains at 91 KIAS. Kit price is $5,995 excluding shipping and han- dling. BLR estimated installation time is three hours. According to Robert de Roche of BLR, the company is evaluating development of a modifica- tion to fur ther increase operating weights. ➤Noise Control— Cabin noise levels remain a major passenger gripe, while temperature control runs a close sec- ond. Both Executive Wings and West Star have developed mods that involve relining the interior of the cabin to deaden sound. Executive Wings says its $7,200 retrofit reduces cabin noise levels by four to six dB. West Star says its mod costs $7,500 and involves the removal and replacement of original insulation with sound dead- ening materials and new insulation. Both firms add inner cabin window Mods, Support, Training and ADs O p e r a t i o n s FROM OCTOBER 1998 BUSINESS & COMMERCIAL AVIATION. © 1998, THE McGRAW-HILL COMPANIES, INC. ALL RIGHTS RESERVED. comes at the expense of a seven to 10 per- cent increase in fuel burned. Both West Star and Executive Wings say reduced block times compensate for the fuel burned, and customer comments support the claims. Each company offers two conversion options. The first is a continued-time conversion, which could be done if engines were approaching an HSI inter- val or needed maintenance. West Star’s Dash 10 continued-time conversion includes an HSI, a gear box inspection, a functional check of accessories (but no accessory overhaul), new hoses and engine mounts, tests and documentation. West Star charges approximately $302,000. Executive Wings charges $267,500 for its continued-time conver- sion. A fully overhauled, zero-time con- version costs approximately $430,000 at Executive Wings and $454,000 at West Star. Executive Wings has completed 65 conversions; West Star Aviation had done 150 as of press time. Thus, 68 percent of the fleet has undergone the engine upgrade. The two firms are fierce com- petitors. Conquest operators interested in upgrading their airplanes are advised to talk to both companies to determine the relative merits. THE MARKET Aftermarket suppliers stress the increase in resale value some modifications add, particularly performance and reliability improvements such as the -10 engine conversion. Resale prices would seem to bear out their claims. Williams of West Star stressed to B/CA that the Aircraft Blue Book Price Digest reports an increase of $18,000 to $19,000 in the last quarter, with estimated market values of even the oldest aircraft of more than $1 million, and that these are for TPE331-8- powered aircraft. Williams claims that -10 Conquests are worth from $250,000 to $300,000 more than unmodified air- planes. Conquest specialists think a number of operators are making investments that represent 25 percent or more of the cur- rent value of their aircraft because they plan to keep operating them well into the future. According to numbers offered by Williams, average total time of the 441 fleet ranges from just under 3,700 hours for late model aircraft to nearly 6,200 hours for early serial numbers. With an annual hourly utilization of 308 hours, there is a lot of useful time left for the fleet. The only life-limited airframe ele- ment at this point are the aileron hinges, which have a 10,000 hour life. If averages are any guide, it will be more than 12 years before the average high-time air- plane approaches 10,000 hours. The bad news is that the returning appeal and the improvements available for the Conquest II have driven up prices and constrained the availability of aircraft at the same time. Popularity comes and goes with air- planes just as it does with entertainers. Yesterday’s dog is tomorrow’s darling, and vice versa. In the current situation, the 441 appears more in the desirable col- umn. As an example, a 1981 model that had depreciated to, or had reached a residual value of—in market demand terms—roughly 64 percent of its original price in 1987 has now climbed back up to 82 percent. B/CA panes. West Star also is offering an active noise control system developed by Lord Corp., of Car y, N.C. Trade- marked NVX, the system weighs approximately 55 pounds and involves the installation of eight speakers and 16 microphones, plus sensors and other system elements in the cabin. Lord claims its 441 NVX reduces propeller noise in the cabin by 12 dB, or 75 percent. Installed price averages $35,000, according to West Star. ➤Customer Support— According to Steve Charles, director of product support for Cessna’s propeller dealer organization, Cessna continues to assign someone to its technical hot line for turboprops. While it is orient- ed toward the dealer support organi- zation—there are about 20 in the United States—it frequently responds to inquiries from operators. Cessna of fers subscriptions to all technical manuals, par ts and tool catalogs and bulletins. New subscrip- tions cost $275 per year in aero- fiche. ➤Operator’s Group— The Con- quest Aircraft Operators Group offers members “a personal knowledge in turbine aircraft operations,” a quar- terly publication, Charlie Tango 425-441, and an annual safety and maintenance conference. Annual dues are $125 in the United States and $150 for operators in other coun- tries. The Conquest Aircraft Opera- tors Group, P.O. Box 460, Valdosta, Ga. 31603. Phone: (912) 244-1568; fax: (912) 244-2604; e-mail: JemOps@worldnet.att.net. ➤Training— FlightSafety Interna- tional offers dedicated 441 pilot and maintenance training at its Wichita Cessna Learning Center: (316) 220- 3200. Pilot initial training consists of five days of ground school and simu- lator training with the option of flight training on the sixth day. Cost is $7,500. Recurrent training runs for three days and costs $4,500. Main- tenance training runs for 10 days and costs $3,325. ➤Accidents— NTSB records con- tain 22 CE-441 accidents between May 12, 1983 and March 8, 1997. Nine were fatal. Probable causes range widely from fuel mismanage- ment (including one accident that occurred during a drug run after the pilot exhausted the fuel supply) to poor decisions or improper proce- dures during instrument approaches. ➤ A i r w o r t h i n e s s Directives— Major air frame and operational ADs issued on the 441 include: 79-08-07—Propeller anti-icing elec- trical wiring modification. 79-09-02—Aileron control surfaces drainage. 79-19-13—Elevator trim tab. 80-02-17—Flight manual perform- ance. Data was changed for aircraft through S/N 0097 and replacement of certain fuel control units and relat- ed actions. 83-12-03—Batter y switch wiring. Inspection and modification as need- ed of the dual switch wiring. 84-20-02—Nose landing gear actu- ator rod end replacement. 85-25-11—Nuts (Cessna P/N NAS1291-8). Replacement of the hor- izontal stabilizer front spar attach bolt retaining nuts with new ones available only from Cessna. 86-24-13—POH/AFM appendix- icing. Revises engine management procedures in icing conditions. This could present operational problems, since it requires activation of the engine ignition override mode, which is time-limited. 92-16-07—Horizontal stabilizer front spar. Applies to all 441’s and requires repetitive dye penetrant inspection, at 2,000 hour intervals, of the horizontal stabilizer forward attach bulkhead for cracks. The str ucture must be replaced if cracks are found before further flight. Installation of SK 441- 103A is terminating action for the repeat inspections. 95-25-10—Replace outflow/safe- ty valve. (Requires the replacement of cabin pressure outflow valves to prevent cracking and depressuriza- tion). FROM OCTOBER 1998 BUSINESS & COMMERCIAL AVIATION. © 1998, THE McGRAW-HILL COMPANIES, INC. ALL RIGHTS RESERVED.