Paul Bowen

LeaIjet 60 operators, at times, soundas though they are paid sales staff.They crow about the aircraft climbingdirectly to FL 410 in 11 to 14 minutes.They say it rivals the Learjet 35 fordirect operating cost. They claim itoffers more cabin comfort than anyprevious LeaIjet they have operated.

These same operators, however, are

42 Business& Commercial Aviation. July 1995

anything but Pollyannaish about theaircraft's limitations and produc­tion growing pains. Repeatedly, weheard complaints about undersizedwings and wheel brakes, and weakbatteries. They also say its baggagevolume and potty capacity are toosmall. As for the lack of a Learjet 60simulator, one operator quipped, "The

recurrent training program is more orless ajoke."

We surveyed close to 85 percentof U.S. Learjet 60 operators in May,and they also told us why they chosethe aircraft and how they use it. Wealso asked Learjet what the companyis doing to address the concerns ofoperators.

Today, side-facing seats must meet even-more-stringent crashworthinessregulations if they are going to be certified for use during takeoHs and landings.

BusinessAviBlion

COVER STORY

WHY A LEARJET 60?Most Learjet 60 operators are long­term Learjet operators, typically for­mer Learjet 35 or Learjet 55 owners.Many have had Learjets for more thantwo decades.

Some people told us they didn't con­sider buying anything else becausethey were comfortable with Learjet

performance, systems,maintenance require­ments and product sup­port. A few operatorsalso have CanadairChallengers in theirfleets, and they havebeen so impressed withproduct support thatthey wanted to acquireanother aircraft in theBombardier family.

Most of our surveysubjects, though, con­sidered other aircraftat the time of purchase.The closest competitorwas the Citation VII,but it fell short becauseit couldn't fly coast­to-coast westboundagainst prevailingheadwinds.

The operators alsohad looked at the IAIAstra, and while theyliked its advanced wingdesign and range, theysaid it was short onclimb performance andpassenger comfort,compared to the Lear­jet 60. They consideredHawker 800 and 1000aircraft because of

cabin comfort, but opted for the Lear­jet 60 because of better performanceand lower operating cost.

A key purchasing factor, accordingto operators, was low acquisition andoperating costs. "You just can't beatthe value" commented one operator.Another bottom-liner said, "Walletsize is a major consideration [whenyou purchase an aircraft]."

MISSION PROFILEThe Learjet 60 can fly more than 2,250nm with six or seven passengers andland with NBAA IFR fuel reserves,depending on how much optionalequipment is installed. But, that's nothow most operators fly the aircraft.

Most operators say they typically fly550 to 600 miles, on "briefcase mis­sions" with four to five passengers.Some operators frequently fill sevenseats on such 1.3-to 1.7-hour block-to­block missions. Most aircraft areordered with a club and one-half seat­ing configuration-four club chairs inthe aft cabin and two forward-facingchairs up front. Many operators havepurchased a two-seat, side-facingdivan that can be installed in place ofthe right, forward passenger chair.

They told us that the aircraft regu­1arlyclimbs directly to an initial cruisealtitude of FL 390 to FL 410 on suchmissions-in 11 to 14 minutes. They

Business& Commercial Aviation. July 1995 43

OPERATOR SURVEY

PRAISE FOR AVIONICSThe Collins Pro Line 4 receivedhigh praise from LeaIjet 60 operators. Theavionics package frequently made the top-five list of favorite features.Some users ranked "avionics" as the best attribute of the airplane.

Early aircraft, however, were prone to water leaks through the gasket ofthe angle-of-attack probe housing, causing shorted air-data computers andother avionics malfunctions. A few operators also reported some EFISproblems, but these complaints were not widespread.

Customers appreciate the large format, integrated-display EFISscreens-a first for LeaIjet. Previous models used smaller EADI and EHSItubes.

The sophisticated avionics, however, requires a few minutes of datainput time prior to taxi. The crew cannot set the bug speeds, initialassigned altitude and FMS flight-plan data until aircraft power is on. And,the avionics system "forgets" most of those inputs if electrical power islost, so flightcrews-in the absence of APU or GPU electrical power­must wait for engine start before programming the system. An upcomingservice bulletin will move the FMS power supply to the battery bus, thuscontinuously supplying it with electrical power needed for its volatilememory.

Users also pointed out that in the event of a double-generator failure,the EFIS, FMS and most Pro Line 4 equipment must be turned off to con­serve battery power. However, the batteries can power the standby flightinstruments for more than three hours, thereby allowingthe aircraft to behand flown safely,below 38,000 feet, to an emergencydivert airport.

Some survey respondents, especially those who fly transoceanic mis­sions, would like to see a third, standby electrical power source, such as anair-driven generator, hydraulically driven generator or an APU certifiedfor inflight use.

Operators were especially enthusiastic about the optional UniversalAvionics Systems UNS-1B FMS, but, until recently, the box couldn't pro­vide access to certain Pro Line 4 diagnostic and service functions. Soft­ware version 4.04 fixes that problem.

Universal plans to release a 4.05 upgrade later this year that will pro­vide a GPS non-precision approach capability.

44 Business& Commercial Aviation. July 1995

cruise the aircraft at 0.76 to 0.77 indi­cated Mach number (IMN) if maxi­mum range is not a factor, resulting ina true airspeed of 435 to 440 knots.

Operators make the LeaIjet 60 earnits way. The majority of users say theyfly 550 to 700 hours per year. A second(and much smaller) group fly 250 to400 hours per year, and a few fly 800to 1,000hours annually.

Depending on annual utilization, theaverage direct operating cost theyreport is $750 to $900 per hour. Mostoperators with whom we spoke partici­pate in Pratt & Whitney's Eagle Ser­vice Plan, a pre-paid maintenance andextended engine protection plan thatcosts a total of $287.50 per hour. "It'scosting us 11 percent less to operatethan our [LearjetJ 55," said onepleased operator.

The crew multiple-the number ofcrews available to fly the aircraft-isabout evenly split in thirds. Operatorsreport they have 1.0, 1.5 or 2.0 crewsper aircraft.

PERFORMANCE!When asked to name their five favoritefeatures, Learjet 60 operators almostinvariably put "performance" at thetop of the list, which comes as no sur­prise judging from their mission pro­file reports. They told B/CA that theaircraft quickly accelerates through

red line after level-offatFL 390 to FL

410, if theydon't

Fred George FlightSafety International

SIMULATOR NEAR READYAccording to operators, fuel econo­

my is yet another of the Learjet 60'sstrong suits-if the aircraft is flown atthe appropriate cruise altitude. Theyreport first-hour fuel burns of about1,700 pounds and subsequent-hourfuel burns of 1,200 pounds or less. "Itburns the same fuel [in cruise] as ourold LeaIjet 35," commented one opera­tor. Combine low fuel-flowswith 7,910pounds of usable fuel, and the result isa comfortable 2,400 to 2,500 nm, oper­ators attest. "Count on seven hours totanks dry," said one operator.

Operators aren't as impressed withthe Learjet 60's runway performanceand relatively high V-speeds. "It lovesthe ground," carped one operator.His comments were echoed by manyothers.

The Learjet 60's balanced fieldlength performance actually is aboutaverage for a mid-size business jet.The Learjet 60's landing distance, incontrast, is decidedly longer than anyother mid-size jet, in part because ofits relatively high landing referencespeeds.

CABIN COMFORTPrevious Learjet operators, especiallythose who fly shorter hops, wereenthusiastic about the Learjet 60'smain cabin and passenger amenities.One operator commented, "The cabinacts a lot bigger than our [LeaIjet] 55,in part because it has much betterchairs." Many praised Learjet's Tuc­son completion center for the quality

Business& Commercial Aviation. July 1995 45

speeds than in any Long-Horn wingLearjet. The increase in angle ofattack results in a double disadvan­tage: higher stall speeds and a lowerMach limit at high altitude.

Simply put, operators say the Lear­jet 60 leaps up to the optimum cruisealtitude for a specificgross weight, butit doesn't want to climb any higheruntil it's much lighter, because of therelatively high induced drag. Said oneoperator, "Its 51,000-foot capability isway overstated."

LeaIjet is quite candid in responding to operators' complaints about theprior lack of a LeaIjet 60 simulator. "There's no good answer [for why itwas delayed]," company President and CEO Brian Barents admitted.

The LeaIjet 60 simulator, now installed in FlightSafety International'sTucson facility, was slated for FAALevelD approval by the end of June.

B/CA had the opportunity to "fly" the simulator in late May, and wewere indeed impressed. The control feel, motion and systems response areall first rate. In addition, the visuals are a cut above anything we've seenin a previous Learjet simulator, and they add a higher levelof realism.

Most survey respondents with whom we spoke said simulators are criti­cal to pilot training. We noted, for example, that the high flight-idle speedand residual engine thrust discount the value of simulated one-engine­inoperative training maneuvers in the actual aircraft. Also, many otheremergency maneuvers are too dangerous to practice anywhere but in asimulator.

The new simulator is versatile, flexible and realistic. It may be config­ured with either the Collins AMS-850 FMS or Universal UNS-lB FMS.The weather radar can detect simulated cloud build-ups. Note: Failure toavoid thunderstorms in the simulator will result in a cold-sweat, high­impact, attention-riveting, thrill ride that no one would want to duplicatein real flight.

promptly pull the thrust levers backfrom the maximum cruise detent.

A heavily loaded Learjet 60 can bepushed to FL 430 to FL 450, but sur­prisingly, fuel economy takes a nosedive. Why? The LeaIjet 60 uses essen­tially the same wing as the Learjet31A, resulting in the heaviest wingloading of any Learjet-heavier, infact, than other mid-size jets. Thatprovides a comfortable ride, but thereis an aerodynamic downside: a higherangle of attack at climb and cruise

OPERATOR SURVEY

FLYING IMPRESSIONS

batteries as often as every 70 hours,"one user reported. Learjet is testinglarger-capacity, lead-acid batteriesmanufactured by Concorde, and theyshould be available by the middle ofthe year.

Learjet now offers an optional APUthat provides electrical power duringground operations and virtually elimi­nates forward-c.g.problems because ofits location in the tailcone equipmentbay. The APU eliminates the batteryproblems, provides electrical power forthe auxiliary cabin heating and vapor­cycle air-conditioning systems, andallows avionics to be programmedprior to main engine start. (See"Praise for Avionics" sidebar.)

Cabin comfort is one of the frequent­ly mentioned strong points of theLearjet 60, but cabin noise---€speciallyfrom the air distribution system­annoyed many customers. Learjet nowoffers an air-duct muffler kit andredesigned windshield piccolo tubes(perforated defog air distributionducts) as a no-cost upgrade to helpquiet the cabin. An upgraded acousti­cal insulation package-installed asstandard equipment in current-pro­duction aircraft-also is available atextra cost to soak up four to five dBAof interior sound.

Early production aircraft had pres-

An optional APU eliminates operatorcomplaints of weak batteries, andprovides electrical power in lieu of theengines.

impressed by the quality of the interi­or completion, high cabin-sound levels,imperfections in the paint and a com­paratively narrow center-of-gravityenvelope. One user told us, "Learjetshould have put more avionics gear inthe tailcone equipment bay, like theydid in the [Learjet] 55" to ease center­of-gravity problems.

Many optional avionics boxes wererelocated to the aft bay in laterproduction aircraft, thus moving aftthe center of gravity, as we observedwhen we visited the Tucson comple­tion center in late May. Learjet alsohas widened the published center-of­gravity envelope and increased theMTOW by 400 pounds, to 23,500pounds, thus increasing loadingflexibility.

Weak lead-acid and NiCad batterieswere another complaint, according tomany operators who participated inthe survey. "We have to service the

GROWING PAINSWe heard the most complaints fromoperators of early-serial-number Lear­jet 60 aircraft. (One operator said, "Itwas rushed to market before it wasready.") These operators were not

There are notable differences between Learjet 60-0005,which we flew twoyears ago, and the current factory demonstrator 60-0048 that we flew inlate May with Robert W.Agostino, Learjet's director of flight operations.

After engine start using a GPU, we noticed the new aircraft's interior isnoticeably quieter because of the improved cabin-air distribution systemand upgraded acoustical insulation.

Agostino calculated the takeoff reference speeds for the Learjet60 weighing 19,000 pounds and departing from Tucson on a 75cF day:117 KIAS for Vl, 128 KIAS for VR and 135 KIAS for V2 for flaps 20degrees. The published aircraft flight manual balanced field length (BFL)was 4,390 feet. If we had departed at the 23,500-pound MTOW, in con­trast, V2 would have been 147 KIAS and the BFL would have been 6,830feet.

Prior to takeoff, Agostino pointed out that setting takeoff thrust onlyrequires the power levers to be pushed ahead to the third click detent; nofine tuning is needed. Once cleared for takeoff, we did just that. It takesseveral seconds for the engines to accelerate from ground idle, but oncethe rpm reaches 70 percent, the thrust increases quickly, providing thewell-known Learjet shove in the backside.

We were cleared for a direct climb to FL 410, and for most of the ascentthe temperature was about 10cC warmer than standard. Twelve minutesafter brake release, we leveled off at FL 410, accelerated to 0.77 IMN andpulled the thrust levers back to 1,150pounds per hour total fuel flow.

Returning to Tucson, we made the final, full-stop landing using maxi­mum reverse thrust. Learjet 60 operators told us the thrust reverserswere most effective, and we weren't disappointed. The deceleration rate isimposing, and the FADECs automatically reduced thrust to idle at 50knots to help prevent FOD. Agostino advised against using reverse thrust(even at idle rpm) below that speed to prevent FOD ingestion.

We shut down one engine after clearing the runway to avoid excessiveuse of the brakes while taxiing back to the ramp.

The Learjet 60 has benefited from two years of refinements. It is no lessof a sporty Learjet than when first introduced, but now it's a more com­fortable, economicaland practical work tool for its passengers.

of the interior cabinetry, chairs, uphol­stery and fittings. "You can see theCan adair Challenger influence,"explained another, referring to the CL601 aircraft completed by the Tucsonfacility.

"Business aircraft" is a term thatvery much applies to the Learjet 60,according to operators. They appreci­ate the 117 VAC power outlets for lap­top computers and other officeequipment. Some were particularlyimpressed with the Magnavox Mag­nastar digital radiotelephone system."It has true, two-channel operationand exceptionally good ground cover­age," one operator volunteered.

46 Business& Commercial Aviation. July 1995

FADEC FIRST FOR LEARJET ENGINESPratt & Whitney Canada (P&WC)PW305Aengines on the Learjet 60 rankhigh among operators' favorite features. The turbofans are flat-rated at4,600 pounds-thrust for takeoff up to 74°F,but APR extends that thrustrating to 88°F.

The full-authority digital engine controls (FADECs)-a first for a Lear­jet-automate most functions including start, takeoff thrust setting,thrust adjustments for anti-ice bleeds and even automatic relight, shouldthe need occur.

A few of our interviewees noted it is difficult to make small powerchanges because of the calibration of the electronic power levers-knownin techy terms as "rotary variable differential transformers." The onlyconnections from the RVDTsto the FADECsare electrical wires.

Operators of early Learjet 60 models told B/CA that occasionally theyexperienced ENG CMPTR light annunciations, but it seldom caused themto abort a mission. Later model aircraft don't appear to be as prone to theproblem.

Cracked combustion liners, however, are a major source of concern. Onehigh-use operator told us his firm has changed five engines and six linersdue to stress cracks near the igniter bosses in the liners. In response,P&WC has issued Service Bulletin 24317, specifying a slimmer-nosedigniter that provides increased clearance from the combustion liner, there­by reducing stress between the two structures when minor thermal distor­tion occurs. P&WC also issued SB 24349, an updated combustion linerwith a double-weldedigniter boss and a ceramic thermal barrier coating toreduce heat stress and distortion. Both service bulletins are field updates,and they are covered by the engine warranty or P&WC's Eagle ServicePlan.

The Learjet 60's contours, including theengine nacelles and pylons, were mademore slippery by using NASA/BoeingTranair softWare.

surization systems that rather abrupt­ly bumped the cabin altitude duringaircraft-altitude changes. Relocatingthe jet pump that provides servo vacu­um for the pressurization controllersolved the problem by slowing theactuation of the cabin-outflow valves.The upgrade is offered at no cost tooperators of early aircraft.

The lavatory was another sore point,especially from operators who flytranscontinental and transoceanicmissions. Customers complained thatthe potty's wastewater capacity istoo small, and that it uses non-stan­dard chemicals and non-standardexternal servicing fittings, requir­ing special adapters. Learjet Incorpo­rated, in response, is developinga standard, "blue-water" pottywith double the fluid capacity andimproved venting. The new potty, slat­ed for certification late this year,will be offered as a no-cost upgradeto present Learjet 60 customers,and it will be standard equipment infuture aircraft.

Operators said they want moreexternal baggage capacity and morecarryon luggage room. Passengershave to stow most of their carryon lug-

gage in the compartment aft of thelavatory on typical out-and-back"briefcase" missions. There is no planby LeaIjet, however, to increase carry­on luggage space or external baggagevolume.

Early model Learjet 60 aircraft hadno heating in the unpressurized, exter­nal baggage compartment, causingaerosol cans to freeze and burst. Lear­jet recognized the problem and nowoffers an aft baggage compartmentheating system as a no-cost upgrade.

Operators told B/CA that the air­craft needs a bigger wing and largerwheel brakes. There is no cost-effec­tive solution to those fundamentaldesign aspects. A Learjet engineernotes that the wheel brakes "arecompletely capable of handling theenergy required for emergency stops."Our survey subjects don't disagreewith Learjet's engineering departmenton that essential point, but theybelieve that excessive wear and rela­tively long published landing distancesprove their point about undersizedbrakes.

By the end ofthis year, Learjet plansto offer an automatic ground spoilerdeployment system that will reduce

published balanced field length dis­tances by 300 feet.

Brake wear was a problem duringthe first several months of Learjet 60operation because the thrust reversersweren't yet certified for use. Now thatuse ofthe thrust reversers is approved,brake wear is greatly reduced, butoperators told us they must be carefulin using maximum reverse thrust oncontaminated runways because of thepossibility of foreign-object damage tothe engines. The thrust reversersshould be stowed at 50 KIAS to pre­vent possible particle ingestion by theengines.

Operators also had complaints aboutthe cockpit checklist, runway perfor­mance data, avionics system limita­tions and engine hot-section parts.(See "FADEC First for LearjetEngines" sidebar.)

One customer, reflecting on thecompany's overall commitment to theLearjet 60 upgrades, said, "LeaIjet hasreally worked with us [on theseissues]." Most people with whom wespoke shared that belief.

OVERALL SCORECARDMost of the Learjet 60's growing painsare related to its unprecedented range

Business& Commercial Aviation. July 1995 47

OPERATOR SURVEY

But there were caveats. "Unlike pre­vious Learjets we've operated, youcan't fill up the tanks and fIll up theseats." One reason is optional equip­ment. Operators frequently orderTCAS, GPWS and cabin entertain­ment systems. For example, the cur­rent Learjet 60 demonstrator weighs500 pounds more than the B/CAequipped weight.

Other survey respondents com­mented that they wished the Learjet60 were backed by the quality of prod­uct support and technical representa­tives associated with the CanadairChallenger. The Challenger servicecenter, for instance, assigns a lead per­son who assumes full responsibility fortask coordination and completion of acustomer's airplane.

Would any of our intervieweesbuy another Learjet 60? Commentsranged from lukewarm to mostlyenthusiastic. Among the tepid an­swers: "We would look at the Hawker800, but probably would buy anotherLearjet 60." Or, "We would buy thelatest serial number aircraft," and"We're watching the Learjet 45 veryclosely." Enthusiasts proclaimed:"Most assuredly!" "We've been reallyhappy with the airplane" And, "It's ariot to fly." B/CA

Learjet is developin"l a standardizedchecklist format similar to theChallenger checklist. The pages are

larger, systems diagrams are included,and colored index tabs make it easierto identify each section.

In the Works~High-Capacity, Blue-Water Toi­

let (Fourth Quarter 1995)~More Powerful Batteries (Third

Quarter 1995)

Group II (Additional Cost)~SB 60-25-3 Improved Cabin

Soundproofing, $49,800~SB 60-27-6 Automatic Ground

Spoiler Deployment, $10,200~SB 60-34-2 UNS-1B 404 Soft­

ware

Group I (No Cost)~SB 60-21-3 Cabin Pressuriza­

tion Improvement~SB 60-21-4 Auxiliary Heating

System UpgradeSB 60-21-6 ECS Noise Reduction

Package~SB 60-21-7 Tailcone Baggage

Compartment Heater~SB 60-21-1Pro Line 4 Phase III

Autopilot Upgrade~SB 60-23-1 Pop-up Radiotele­

phone

SOME UPGRADEOPTIONS

Brian Barents, Learjet's presidentand CEO, doesn't pull any puncheswhen answering questions aboutthe Learjet 60's early production­model problems. "The good newsis that we've already addressedthe problems operators haveidentified."

Barents said that the firm deliv­ered 22 Learjet 60 aircraft in 1994,and he expects to exceedthat num­ber this year. One of the reasonsfor his confidence is Learjet'saggressive stance on productimprovement.

Specifically, Learjet now offersthese upgrades:

the aircraft for hj.gh reliability. Previ­ous Learjet customers found it easyto work on the aircraft. It takesapproximately 20 minutes, for exam­ple, to remove or replace the optionalAPU-a must to gain access to thebatteries and most systems in the tail­cone bay.

and cabin volume compared to that ofprevious Learjets. Operators of 20s,30s and 55s having intra-continentalrange seldom complained of the lack ofan APU, too little potty capacity orthe need to program avionics priorto engine start. Without question,the Learjet 60 is stepping up intothe intercontinental and trans­oceanic business-aircraft class thathistorically has been dominated byheavy-iron.

Despite that explanation for theaircraft's reported shortcomings, oper­ators still believe that the aircraftwas pushed into production beforeit was ready. There has been prog­ress, though. "We're now getting pastsome of the early problems," noted oneuser.

Don't mistake all of those com­plaints as an indication of operators'dissatisfaction with the Learjet 60. Allbut a few would strongly recommendpurchase of the aircraft to theirfriends.

"Personally," an interview subjectsaid, "I don't think you can beat aLearjet 60." We also heard, "It's anexcellent value;" "try to find some­thing in a mid-size [jet class] that goesfaster or performs better;" and "a hellof a goodairplane."

Operators frequently complimented

While access to the aft baggagecompartment is simple, many operatorssaid they wished the total baggage­volume capacity was greater.

48 Business& Commercial Aviation .July 1995