Proud to Fly a Turboprop_ Q400 vs ATR72

Q400 in Spicejet Colors

It’s time for another A vs. B comparison. This time around though, it isn’tbetween Airbus and Boeing, but the world’s two most popular regionalturboprop aircraft, the ATR‐72 and the Bombardier Q400.

The Indian short haul segment was, and is ruled by the ATR 42 and the ATR 72turboprop aircraft. A product of the venture between Alenia Aerospace ofItaly and European Consortium EADS, the ATR enjoys a monopolisticpresence at the small airfields of India, low traffic density routes, or thechallenging airfields of the north and the north east. If it’s one aircraft that

most airfields know, it’s the ATR 72/42. No other aircraft flies to as many airfields as does this family.

Unsurprisingly, this extremely popular ATR 72 is also the most dreaded amongst the

flflying public. The stereotyped image of an aircraft withpropellers forces many to raise their eyebrows. But theflights are short and the fares low, making the experiencebearable. But to the airlines, its aircraft like the ATR thatbring in the money. No wonder that Kingfisher employs25 ATR 72‐500, while Jet flies 20 of the same type. It’smuch more economical to operate a turboprop than a jet.Any day.

Not being the first airline in the country that employsaircraft type that are in appearance different from theaircraft type that their airline name suggests, Spicejet ispoised to please Bombardier with the gradualintroduction of 15 Q400 turboprop aircraft, to flymissions similar to the ATR 72‐500. And for the first time in India, the public may in fact be “Proud tofly a turboprop”. With a quiet cabin that is quieter than some jet airplanes, seats that are claimed to bemore comfortable, windows that allow for a greater view of the magnificent terrain, huge overheadstowage that can fit your trolley bags, and speeds that lag a jet by only 3‐5 minutes on a typical 1 hrroute, while being much cheaper than a jet aircraft of comparable capacity, the Q400 will deliver a jetexperience at a turboprop’s economics. Poised to revolutionise the experience of short haul flight, arethe “DASHing” Q400 NextGens from Bombardier Aerospace.

In this article, focus shall be on the Q400 NextGen, while also fairly comparing the two aircraft that willdivide the short haul skies over the Indian subcontinent. Sit back and relax, while we serve you theturboprop of your choice.

Turboprop in India

It was in the October of 1999 when an ATR72‐500 was inducted by Jet Airways, marking the dawn ofthe turboprop era amongst private carriers in India. According to Nikos Kardassis, CEO of Jet Airways,

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“The turboprop is ideal from a cost perspective to service small feeder routes given the traffic (demand) tocapacity (supply) ratios and more importantly for their operational economics. Given this rationale we havefelt that the turboprop is ideal for some destinations on our domestic network. These aircraft are especiallyideal when it comes to providing air links to smaller towns and cities given that some of the existing airportshave only just been remodelled to accommodate such smaller aircraft.” The economics of a turboprop madeimmediate sense on short haul routes, opening markets previously considered unprofitable to operateon. Air Deccan, which was all about economics, started operations with four ATR 42‐500s in theAugust of 2003. Kingfisher Airlines inducted their first ATR 72‐500 in the March of 2006. In a businesswhich promises hairline profits, turboprop aircraft seem to be the only way to open up new marketsand still make profit with low load factors. But the subcontinent knew only one manufacturer: ATR.

The need for something better

Kingfisher Airline’s Bangalore‐Pune sector has a block time of 1hr 20 minutes when operated by theirAirbus A320. The same sector, when operated by their ATR 72‐500, takes 2hours. This ATR flightoperates at close to midnight, when passenger traffic is low, and speed is of no great concern. But atother times of the day, when demand is high on other short haul sectors, one would foresee the needto introduce an aircraft that can fly a similar number of passengers, with similar operating costs, whilegenerating a higher revenue potential by operating more flights per day. To reword, an aircraft thatflies almost as fast as a jet and yet, is as economical as a turboprop: the ideal crossbreed.

The “PropJet”

Considering that Spicejet would like to honour the last three letters in their airline name, the airlineplaced a firm order for 15 Bombardier Q400s towards the last quarter of 2010, with options on another15. The Q400 is Bombardier’s answer for a regional turboprop that replaces a jet, while behaving like ajet and yet, significantly reducing aircraft noise and fuel consumption.

The Q400 and the ATR 72 aircraft are both twin engine, turbo prop aircraft capable of carrying around70 passengers. Both aircraft have a high wing, with six bladed propellers attached to Pratt & Whitneyengines on the wing. Both sport a “T” tail, and four abreast seating. The ‐600 variant of the ATR 72features a full glass cockpit, much like that on the Q400. This is where the similarities end.

The Q400 is a much longer aircraft, which appears sleeker, with a spine running all the way from thewing box to the rudder. The engines are larger, and extend beyond the trailing edge, unlike the ATR 72wherein the engine pods taper off under the wing itself. The main landing gear are housed and hingedto the engines, rather than to the belly like in an ATR. The fuselage of the Q400 appears “clean” due tothe absence of this belly. The nose of a Q400 is longer and sharper, while that of the ATR is smaller,and blunt. If one were to go by appearances, the Q400′s looks speak of speed, power andaggressiveness. The ATR 72 appears docile. Here are two cases where one may judge books by theircovers, and not be disappointed by their true performance characteristics.

To start with, the Q400 and the ATR72‐500/600 are similar in weight, but the Q400 is equipped withengines that deliver nearly twice the power of any variant of the ATR 72. The Q400 can cruisecomfortably at a max speed of 360kts, while the ATR 72 cruises at a maximum of 276kts. On a sectorthat takes 2 hours for the ATR 72 to fly, the Q400 can easily fly in under 1 hour 40 minutes, slower thana jet by only around 15 minutes. While the ATR 72 struggles to climb to its service ceiling of 25,000ft(FL250), the Q400 reaches this altitude in minutes. Of course, this performance doesn’t come free: theQ400 can land up consuming nearly 30% more fuel than the ATR 72‐500 on the same sector. Butattempting to offset the cost of enhanced fuel consumption is its capacity to carry between 6 to 12more passengers than the ATR 72, at speeds that are jet‐like, while consuming much less fuel than a jetof comparable seating capacity.


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ATR72 vs Q400 usage in a given operational day

Revenue Potential of the Q400 when compared to a 66 seat ATR 72 and a 72 seat ATR 72

Designed with the performance of a jet but the technology and economics of a turboprop, the Q400stands out as a true regional “PropJet”.

Economics

The primary motivation for a scheduled operator,and more importantly a low cost carrier, to invest inan aircraft is the economics that it promises.

The biggest boon to regional turboprop aircraftoperators in India is that their turbine fuel is underthe declared goods category, attracting a sales tax ofonly 4% as compared to 28% for other aircraftweighing above 40,000kgs. Topping that is theexemption from landing charges for aircraft with lessthan 80 seats. Since both aircraft fall into thesecategories, the economics of a turboprop start

making immediate sense.

The average sector distance in the regionally dense portion of India, the south, is 300NM. Consideringthat at high speed cruise the Q400 takes an average 1hr02min of flying time, and the ATR 72 takes1hr15min, and that both aircraft start operations at 6:00am local, and wrap up by 11:30pm local, theQ400 can easily fit one extra flight in that 17.5 hour period.

Over and above this, the Q400 that Spicejet will receive will be configured with 78 seats. The ATR 72′sin Jet Airways are configured with 66 seats in some and 68 in the other. In Kingfisher, all the aircraftabsorbed from erstwhile Deccan are configured with 72 seats while the rest are configured with 66seats. As a result, the Q400 lands up with a capacity of 6 to 12 more passengers per flight.

Considering that both airplanes have the same hours in the air, that the Q400′s overpowered enginesspend lesser time at a high power to reach cruising altitude, and that the Q400′s engines are not usedon ground in the “Hotel” mode like in the ATR, the expected cost of maintenance of both airplanesmay be considered similar, though the Q400 has strong reasons to be cheaper to maintain. Landingcharges don’t apply to both airplanes, and both airplanes may need two sets of crew to operate theflights in that 17.5 hour period. However, the most significant operational cost, especially in India, isfuel: The Q400′s fuel consumption is nearly 30% more than that of the ATR72 under similar 300NMenvironmental conditions in high speed cruise.

Bombardier claims that in a European Environment, the 78 seat Q400′s direct operating

costs(DOC) for a300Nmsector is8.8% morethan that ofa 68 seatATR72‐500. ATR on the other hand claims that in the same environment, the DOC for a 300Nm sectorfor a Q400 is 25% more than the ATR72‐500. Considering that Bombardier and ATR are on the extremeends of the estimating scale, an average of 16.9% reveals that over this 17.5hr period, the Q400 will cost1.3 times more to operate than the ATR72‐500. Considering ATR72 seating capacities of 66, 68 and 72passengers, the Q400 has 1.31, 1.27, and 1.2 times the revenue generating potential of the ATR72‐500respectively, in the same day. If one were to go by these figures, the Q400 doesn’t do well against a 68


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Q400 v/s ATR 72‐500 Cabin Layout and Doors

or 72 seat capacity ATR72. In fact, even if one were to consider Bombardier’s figures, and comparethem with an ATR72 with 72 seats, the Q400 will only fare as well as the ATR72 (despite the extraflight on the Q400) as far as this conservative, non‐operator specific economical comparison isconsidered.

While available revenue seats, as used in the comparison above, is only indicative of potential, one mayappreciate that load factors, which are dependent on seasons, play a big role in profits. The ATR72s inIndia may break even with a passenger load of around 20‐25 passengers. As per Bombardier,considering a low cost carrier’s cost and fare structure, the Q400 in the US and European 300Nmenvironment breaks even at 45 seats. This means that the Q400 operator must sell significantly moreseats per flight just to break even.

Finally, the acquisition price of both aircraft: The Q400 is listed at approximately US$30M, which isUS$7M pricier than the US$23 million list price of the ATR 72‐600. While these are list prices, usually,the market price is at a discount from the list price which varies based on the aircraft quantity andindividual airline negotiation and deals.

Operations

i. Ground handling

The Q400 that Spicejet will receive will have a singleclass cabin with 78 revenue seats at a 30″ seat pitch; allseats facing forward. With the same comfortable 30″seat pitch, the ATR72 can seat 72 passengers;However, this will include two rear facing seats,causing significant discomfort and loss of privacy forsix passengers.

The Q400 has forward and rear passenger doors onthe left, and a service door on the aft right hand side. Passenger boarding is from the front door, andnot amongst the chaos of the galley service like in an ATR where both passenger boarding and galleyservice occur at the aft doors.

The Q400 has significantly larger cargo compartments with significantly larger access doors ascompared to the ATR72. The cargo holds are dedicated and not segmented, unlike in an ATR72 wherethe main cargo hold situated at the forward fuselage is segmented to allow cockpit access. Besides,both cargo sections on a Q400 may be accessed completely from the outside, unlike in the ATR wherethe rear cargo hold must be accessed from within the cabin. Considering the higher cargo volumetricefficiency, the Q400 has 156% (438ft3) the effective cargo volume of the ATR72 (281ft3).

When it comes to cargo loading, the ATR72′s forward cargo section is easier to load, as the cargo flooris about 1meter high. However, in the Q400, the forward compartment is seldom used for passengerbaggage, and the rear cargo hold, which is about 1.5 high, will require the use of a mobile ramp to loadcargo, as is done with a European Q400 operator.

Both the ATR 72 and the Q400 can comfortably be turned around in 25 minutes.

ii. Ground Power

The ATR72 has a feature by which the right hand engine may be put in the “Hotel Mode”, wherein theengine is kept running at idle power, but the propellers prevented from rotating by propeller brakes. Inthis Hotel mode, the ATR72 is supplied with electrics for aircraft power, and pneumatics for airconditioning. Although the concept of saving costs and maintenance time by using a normal engine for


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ground operation sounds good, it poses some major drawbacks. For one, ground personnel which needaccess to the right side of the aircraft cannot approach the aircraft when the engine is still runningbecause of the safety hazard involved with a propeller brake that may suddenly give way, and secondlybecause of the hot gases from the downward pointing exhaust. This prevents aircraft refuelling, whilealso mandates the service door to be closed. In such a case, the galley needs to be refilled from thepassenger entry, leaving the aircraft with only one entrance and exit for the crew, passengers, andservice.

Besides, in case of a 10kt tailwind in this “Hotel” mode, a nacelle overheat warning may be generated.For this, the operating manual recommends parking the Aircraft with the nose 45° right to the upwind.However, parking stands do not allow for such flexibility.

Due to these multitude reasons, the crew shut it down 9 times out of 10, leaving the aircraft withoutany air conditioning or back‐up power source (at places where no GPU is available). Only in smallerairports like Aggati where the aircraft is not refuelled and no GPU is available, the Hotel mode is keptrunning, but the service door closed, making for very uncomfortable operations with just one door.

Secondly, even when the engine is left on, the air conditioning system rarely performs well enough tomake any difference in cabin temperature (which has now been bettered in the newer ATR 72s).Thirdly, this results in engine wear and tear.

The Q400 on the other hand, has a dedicated ground power source on board with its APU (AuxiliaryPower Unit). The 61kg Hamilton Sundstrand APS 1000 APU provides the aircraft with pneumatics andelectric power, but is limited to ground operations only. The advantages are twofold; firstly, the APUmay be used anytime, at any airport, without any hazard posed to the ground crew. Secondly, andmost importantly, unlike in the ATR, the engine’s life is not affected. A sensor turns off the APU assoon as the aircraft is airborne.

However, the Q400′s source of power on ground also has its share of problems, as around the world,crews had complained about unreliable APUs on board the Q400. After adopting several standardoperating procedures regarding APU operation, their reliability has significantly increased, though itdoes give up once in a while.

Despite using the engine for power, the fuel consumption on the ATR in the Hotel mode is only about110kg/hr, which is almost the same as the Q400′s fuel burn on the APU (100‐150kgs/hr, as observedoperationally). However, when the air‐conditioning on the ATR doesn’t perform well enough, the crewslightly advance the power levers on the engine, resulting in a fuel burn of about 130kg/hr.

But unsurprisingly, ATR72 or Q400, more often than not a ground power unit is used for the electrics,and an air cart (where available) for air conditioning. This saves on aircraft maintenance, and reducesoperating cost by saving on jet fuel.

iii. Flight Ops & Performance.


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Q400 vs ATR 72‐500/600 performance

The Q400′s PW150A engines, each having nearly twice the power of the PW127M/F engines that theATR72s come fitted with, have significant implications on the operational planning of flights with thisairplane.

The maximum takeoff weight (MTOW) of the Q400′s basic version is nearly 28,000kgs, while that of theATR72‐500 is 22,800kgs, making the MTOW of the Q400 23% more than the ATR72. However, thepayload of the Q400, at 8625kg, is only 18% more than the ATR72‐500. This discrepancy is attributed tothe much higher operating empty weight of the Q400, which is about 17,600kgs, 36% more than that ofthe ATR72‐500. The Q400 has bigger (and consequently heavier) engines, and uses little or nocomposites in its aircraft structure, unlike the ATR72 which extensively uses proven lightweightcomposites in the wing, and tail plane.

With the powerful PW150A engines, however, the Q400 has 50% more power per kg of the aircraft atmaximum takeoff weight, in comparison to the ATR72‐500. This extra power is what determines theterrain surrounded high airfields which the Q400 may be operated to, the cruising speed andconsequently the trip time of this overpowered beast.

To start with, the Q400 can take‐off and land from airfields that are 10,000ft ASL, while the ATR72‐500is limited to airfields of 8500ft ASL. At sea level, on a 20°C hot day, a fully loaded ATR72‐500 clears anobstacle 55ft in height, at a distance of 1000m from the end of the runway, while the Q400 clears a125ft high obstacle at the same distance, under the same conditions. This tremendous climbperformance allows the Q400, at MTOW to reach FL200 in 12 minutes, while the ATR 72 reaches thesame altitude in the same conditions in 21 minutes. With both aircraft at 95% MTOW, the Q400 canreach FL250 in 16‐18 minutes, while the ATR72, although certified to FL250, just cannot fly to thisaltitude.

In case of an engine failure, the Q400 can maintain 17,500ft, while the ATR72 with one engine canmaintain only 11,000ft. With a 6,500ft margin, the Q400 can be dispatched to regions with significantterrain, clearing obstacles with one engine that the ATR72 simply can’t.

For example, the sector that the ATR72 is deployed on, in Kingfisher: Dharamshala, is surrounded byterrain on all sides, except the south west. The minimum off route altitude (MORA), in the grid inwhich it is located, is 23,500ft. To the south, the grid MORA is 14,200ft; to the west, the MORA is16,600ft, while to the south west, the MORA is 3,800ft. Since the Dharamshala flight is based on visualflight rules (VFR), the aircraft is dispatched to this hilly terrain, relying on pilot skill to steer clear ofterrain in case of an engine out. Although the standard operating procedures authorizes a go‐around,it is next to impossible at this airfield. The Q400, on the other hand, can easily execute a go‐around.With a single engine out, the Q400 can easily clear terrain on all 3 of four sides, the 23,500 MORA gridbeing the only concern.

For other critical airfields, such as Kullu and Shimla, Kingfisher uses its ATR42 aircraft, due to runwaylength limitations and terrain. The ATR42 has 2,160 shaft horse power (SHP) engines, lending it apower to weight ratio of 0.23SHP/kg at its MTOW of 18,000kg. While this lends the ATR42 a betterclimb performance than the ATR72, the Q400 still outperforms the ATR42 with 0.33SHP/kg, even if theengines on the ATR42 are upgraded to PW127M.

At sea level, and at MTOW, the ATR42‐500 needs 1,165m of runway for takeoff. Under the sameconditions, the ATR72‐500 needs 1290m of runway for takeoff. The Q400, despite its higher mass,higher payload, and higher take off speeds, needs just 1,300m of runway, or lesser when carrying thesame payload as the ATR 72. At certain airfields, such as Shimla, which has a runway length of 1,158m,the Q400 may operate from this runway under reduced load. When taking off from such short airfields


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with a lower mass, the Q400′s climb performance will be significantly greater.

The Q400′s performance is simply amazing for a regional turboprop; it behaves more like a jet. Theaircraft can fly at a maximum true airspeed of 360kts at FL200 (20,000ft above sea level), while the ATR72 hits its maximum of 276kts at FL170. This speed advantage lends the Q400 tremendous flexibility.As experience with other airlines has shown, the Q400 can fly at its maximum speed when behindschedule, or can fly at a long range cruise speed (consuming significantly lesser fuel) when ahead ofschedule. This lends the Q400 greater flexibility than its performance limited European counterpart.

Even the speeds at take off are phenomenal: The ATR 72, on rotation, climbs out at 125kts at MTOW,while the Q400 climbs out at 155kts at MTOW. Upon reaching the acceleration altitude, the Q400 canaccelerate to 250kts much sooner.

Both the ATR72 and the Q400 can pull off high performance approach feats: to maintain approachspeeds much greater than 200kts till a few miles, and then configure the aircraft for landing. TheATR72‐500 can maintain 240kts till 7NM from touchdown; many times, this speed has been maintainedtill only a few miles before touchdown, and yet fast enough decelerated and configured the aircraft forlanding at a speed of 110kts. In this process, turboprop aircraft overtake jets on approach, making jetaircraft the bottleneck in approach scheduling.

The final approach speeds of the Q400 are higher than the ATR72′s: based on weight, and flap settingthe speeds vary from 101kts to 129kts. Typically, the Q400 has a final approach speed of 115kts withflaps 35. While the ATR72 falls into a category “B” aircraft based on speeds, the Q400 falls intocategory “C”. But the approach minima for a category “B” aircraft are lower than a category “C”aircraft, giving the ATR72 the edge over the Q400 in degrading visibility conditions. This can spell thedifference between a missed approach and a landing.

With this jet‐like performance, the Q400 may be treated as a jet, preventing airport congestionnormally attributed to the lack of understanding of a turboprop’s performance by air traffic controllers.For this reason, Bombardier went on a road show in India, educating air traffic controllers of itsperformance. If the ATC treats this as a jet, (which it should with the ATR as well, at least as far asapproach is concerned) , the Q400 can easily fit into jet slots on departures and arrivals, reducingpotential delays associated with turboprop aircraft. This can lead to a better on time performance. Buthow effective the road show has been is to be seen; Kingfisher had tried to get Air Traffic Controllersto fly in the cockpits of ATR72 aircraft to better understand its performance and capabilities, but sadly,that did not work out.

Typical fuel consumption loses the Q400 out to the ATR72. For example, a 296NM mission on anATR72‐500 from Hyderabad to Goa, is planned with a trip fuel of 913kgs, and a flying time of 1hr 14minutes (74 minutes), at FL180 (near MTOW). A Q400 flying 300NM at FL220 for 1hr 7 minutes (5minutes slower than otherwise possible), would require about 1,200kgs of trip fuel. For just a gain in 7minutes over the ATR72, the Q400′s 300kg extra burn isn’t quite appealing. Performance aside, for anATR72 and a Q400 flying 9 flights a day, the Q400 lands up consuming 985,000kgs extra fuel more thanan ATR72, this translating to around INR 4.5Cr in today’s value of ATF for turboprops. While thisfigure appears big, simple math will show that the 300kgs extra fuel will cost INR 13,800more,translating to each of the 78 passengers paying just INR 180 more per ticket, if only fuel were to beconsidered. But airline economic models are complex, and vary from airline to airline.

iv. Maintenance & Dispatch Reliability

The Q400 NextGen promises to keep the aircraft more in the air and less in the maintenance hangar,with intervals between checks significantly increased: the “A” check interval has been extended from400hrs to 600hrs; the “C” check interval has been extended from 4000hrs to 6000hrs. The “A” check


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interval for the ATR72‐500 is 500hrs while the “C” check interval is 5000 hrs. This means that the Q400NextGen can generate significantly more revenue between checks.

While the Q400 will climb at a very high rate and cruise at 360 knots, Augsburg Airways (which fliesunder the Lufthansa Banner) flies at reduced power settings to prolong engine life. The crew climb theaircraft at 850 rpm instead of 900, cruise at 850 rpm, and never exceed an interstage turbinetemperature (ITT) of 670°C while the maximum is 800°C. This results in a climb rate of between 1,800and 2,500 feet per minute, which provides a comfortable cabin attitude for the passengers. Cruise is at345 knots instead of 360. Such engine handling has allowed Augsburg to extend the life of the Pratt &Whitney PW150A engines on the Q400. The prolonging of engine life is not possible on theATR72‐500/600, as the significantly lower powered engines need to be run at higher power settings.

The Q400 has a 99.4% average dispatch reliability, and this figure somewhat surprises Bombardier.“The amazing thing is that we haven’t made structural changes in the basic design of the aircraft; yetthe dispatch reliability is a lot better, probably due to availability of inventory, skilled personnel, andaccumulation of valuable experience leading to better training and understanding of the airplane.”,says Sunder Venkat, director, sales (Asia) at Bombardier Aerospace. ATR claims the dispatch reliabilityof the ATR72‐500 to be over 99%, making both airplanes almost equally reliable for dispatch.

Passenger Comfort

The toughest impression to erase from the minds of the travelling public is the twisted view on anyairplane that has propeller blades. The propeller diameter on the Q400 is 13.5ft, while the fan diameterof the largest jet engine in aviation history, the GE90 engines that power the Boeing 777, is only 10.7ft.

Such dimensions don’t miss the eye, and in the eye of most, any prop is a loud flying machineemploying old technology. The Q400 has two Pratt and Whitney PW150A turboprop engines that drivethe six bladed Dowty (now part of GE Aviation) propellers. A turboprop engine in essence is a jetengine with a gearbox to increase the torque (the turning force) on the shaft which finally drives thepropellers; this increased torque available at the expense of the shaft speed.

But a slower shaft implies slower propellers, and anything that moves slower through the air producessignificantly lesser noise. Yet there will be vibration and noise from the engines and the non shroudedpropeller, but when comparing the noise in the cabin of a Q400 or an ATR72‐500 with the cabin noiseexperienced in the Boeing 747‐400′s upper deck, it’s the mentioned turboprops that stand quieter.Even the noise pollution experienced around the airport from these turboprops is far lesser than mostcommercial jets.

As the propellers turn on the Q400’s engines, they push air up against the fuselage. This phenomenoncauses the fuselage to experience some flexing which can result in unwanted noise and vibration. TheQ400 has engines that deliver nearly twice the power of the PW127M/F engines that are fitted onto theATR72‐500. As a result, there is bound to be more noise and vibration in the cabin. Bombardier gotinnovative, and employed a Active Noise and Vibration Suppression (ANVS) system based ontechnology that was patented around the 1950s to reduce noise in aircraft cockpits. Through thestrategic placement of over 40 microphones, the ANVS system measures these vibration frequenciesthroughout the cabin. This frequency is analyzed and an equal frequency 180 degrees out of phase issent to Actively Tuned Vibration Absorbers (ATVAs). The ATVAs, placed between the exterior andinterior walls, push back against this vibration with the out‐of‐phase frequency to effectively “cancel”the vibration. Since the vibration is cancelled, noise generation is also eliminated right at the source.This system results in a cabin that is up to 28dB quieter than otherwise. In addition, passive noisedampeners, as used in the ATR72‐500, help reduce low frequency noise and vibration.

The Q400 NextGen is the only commercial turboprop available today to make use of the (ANVS)


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system, with which the average cabin noise of 77‐79dBA is lower than that in an Airbus A318/319, andaround 2‐4dB quieter than the ATR72′s cabin. Although a noise difference of around 2‐4dB is barelyperceivable to the human ear, Bombardier states that based on European working standardsmeasurements, this lower noise cuts passenger fatigue by one third.

Any aircraft is at its loudest in the take‐off and climb phases. The Q400 reaches the same cruisealtitude as the ATR72 in around half the time, giving its passengers further respite from noise muchsooner.

The Q400 can, in all conditions, easily reach FL250 (25,000ft), while the ATR72‐500 cannot easily reachthis altitude in most conditions. The result is the Q400 clearing more weather than the ATR72, allowingfor a smoother, less turbulent ride.

Other changes made to the Q400NextGen cabin are mostly cosmetic in nature, such as LED lighting,larger bins, and dished sidewalls; most of which are of no consequence to an economically sensitivepassenger of a low cost carrier.

Safety

A sticky issue for the Q400′s reputation is the series of main landing gear accidents in 2007 thatplagued the Q400 fleet of Scandinavian Airlines, the flag carrier of Denmark, Norway and Sweden.Within a span of 3 days, two Q400s suffered accidents due to the right main landing gear collapsing. Inthe very next month, another Q400 suffered an accident with the collapse of the right main landinggear. The very next day, SAS decided to immediately discontinue the use of the Q400.

Within the same period, an Augsburg Q400 returned to Munich after the nose gear did not extend,and landed with the nose gear up.

The first two SAS accidents were related to severe corrosion in the main landing gear, while the thirdaccident was related to a blocked orifice within the actuator assembly which prevented the completeextension of the right main landing gear. The Augsburg accident was due to a the corrosion of a spring.

But this was not all. An All Nippon Airways (ANA) Q400 landed at Kochi, Japan, with a the nose gearretracted. This led Bombardier to advise all Q400 operators around the world to inspect the aircraft’sfront landing gear door mechanism. A Porter Airline’s Q400 had to return shortly after takeoff fromMontreal’s Trudeau Airport when the landing gear failed to retract after takeoff. In another PorterAirline’s incident, the landing gear would not extend the normal way, and had to be lowered using thealternate mechanism. In two other SAS incidents, the landing gear failed to retract after takeoff.

All the above incidents, with the exception of one in the December of 2006, occurred in 2007.

But the signs of an impending accident were present, and an early flag was raised by Japan’s CivilAviation Bureau (JCAB) in 2006 itself. JCAB had asked Bombardier to improve the reliability of theQ400s, following 52 cases where Q400s had declared emergencies or had to return to departureairports. Following the accidents involving the SAS Q400s, the Accident Investigation Board ofDenmark recommended reviewing the design, the certification and the maintenance program of theMain Landing Gear retraction/extension actuator and rod end. In 2008, the FAA proposed anAirworthiness Directive that mandated incorporation of new weight‐on‐wheels (WOW) and steeringharnesses that have a new conduit construction. The Q400′s reputation for safety was literally on shakylegs.

Bombardier introduced modifications to the in‐service fleet following the SAS incidents. Thesemodifications have been incorporated in the Q400 NextGen aircraft, including a new metallurgyapplied to the actuator piston and rod in the main landing gear.


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Bombardier states that the landing gear has been modified “to overcome even potential maintenanceissues”. Since the modifications, there have been no issues with the Q400′s landing gear.

In all of these incidents and accidents attributed to system error, not a single life has been lost. On theother hand, the ATR 72‐212 (the predecessor to the ATR 72‐500, though no major differences lie in thetwo types), has taken away 136 lives in two accidents spaced 16 years apart; both accidents a result ofthe same issue: icing on the wing leading to loss of control. The ATR 72‐500 has been suitably modifiedto better handle icing, and has a clean safety record.

Another situation that could lead to a partial or full loss of control could be a control surface jam. Boththe ATR72 and the Q400 have a provision to disconnect the otherwise linked elevators, allowing for thecaptain or the first officer to have full authority over their respective, independent elevators. But incase of a control wheel (yoke) jam, ATR pilots have to do with nothing but the rudder and power leversto change the aircraft’s heading. Pilots who experience this during training find it very hard to controlthe aircraft. The Q400, on the other hand, can disconnect the captain’s controls from the first officer’s,allowing the captain to control the hydraulically operated roll spoilers, and the first officer to controlthe mechanically linked ailerons. Whichever gets stuck, allows for the other to be used.

The main landing gear for the Q400 extend from the engine pods, giving it a wheel base of 8.8meters.The ATR72, however, has the landing gear extending from under the belly, giving it a wheel base ofonly 4.10 meters, less than half that of the Q400. As a result, the Q400 on the ground is far more stablethan the ATR72, in all conditions.

The Pratt and Whitney PW150A is a dependable engine, with the engine as such never giving anyproblem. In flight shutdowns, though rare, are usually precautionary in nature, and are linked to amalfunctioning Propeller Electronic Control. Precautionary shut downs, when necessary, are seen inthe ATR 72′s PW127 engines as well.

Single Engine ceilings for the Q400 and the ATR 72

But when an engine fails, the Q400, with the remaining engine, can climb at nearly double the rate ofan ATR72‐500 under similar conditions. Besides, the single engine ceiling of the Q400 is 6,500ft more,making the Q400 far safer, and more dependable in hilly terrain.

The Q400 has one dedicated type II/III emergency exit on the forward right, and three Type I doors.The ATR 72 on the other hand has two plug emergency Type III exits, in addition to two Type I doors.Type II exits are at minimum 20% bigger than Type III exits, and are at floor level, unlike Type III whichcan be as high as 20 inches above floor level. In case of an emergency, evacuation through one TypeII/III and one Type I exit, like in the Q400 (one side evacuation) is potentially much faster than throughone Type III and one Type I exit (like in the ATR).


10 of 27 4/19/2014 23:32

An Augsburg Q400 being hand flown.

Aircraft Handling and Other Systems

Ask any Q400 pilot who has flown both jets andturboprop, and he will hands down cite his love for the“Propjet” hybrid.

Infact, the aircraft’s engines are so powerful, and theQ400′s aerodynamics so favourable that it holds threerecords for climbs to 29,527 ft, as submitted to theFédération Aéronautique Internationale. In the C1i(16,000kgs – 20,000kg) category, the Q400 holds therecord at 07:02 minutes, 59 seconds faster than the Saab2000. In the C1j category (20,000 kg to 25,000kg), theQ400 holds the record at 08:21 minutes, 03:04 minutesfaster than the GrummanE2C Hawkeye. In the C1k

category (25,000kg to 35,000 kg), the Q400 climbs in 11:41minutes, with no aircraft holding a previousrecord. The Q400 is undoubtedly the fastest amongst regional turboprop aircraft.

According to Mark Brouwer, a first officer on the Q400 at Augsburg Airways, a regional airline based inGermany, “When the Q400 is light it’s almost as nimble as a small General Aviation aircraft (such as aC152), and is a dream to fly. The climb performance on take off with a light Dash is just insane: on aferry flight, with normal take off power (90%) in standard conditions, flaps 5, speed V2 + 10 (around140‐145kt), the Q400 will gladly take you to the skies at just under 5000 fpm with a pitch of around27‐28 degrees. When quickly reducing power during cruise the propellers will immediately move intoshallow pitch, causing so much drag from the twelve R408 propeller blades that you can feel yourselfgetting gently pushed forward as the aircraft decelerates. Landing an aircraft with these characteristics(and where 1% change in power makes quite a difference when there’s just over 5000 shp per enginebehind it) can be a great challenge, but that makes it all the more fun.

A heavy Q400 will feel a lot more sluggish, maybe even jet‐like due to its sleek profile. All V‐speeds aregreatly increased, and the reason why Bombardier decided to use such powerful engines becomesquite apparent, as the expected initial climb rate in aforementioned conditions is reduced to around1700 fpm.”

Hydraulic controls are necessary for such a long aircraft, and with the exception of the ailerons, allprimary and secondary flight controls are hydraulically powered. The ATR 72 has hydraulics poweringonly the roll spoilers and flaps, which can make flying the ATR physically more demanding.

In both aircraft, flaps are hydraulically powered, though the Q400 offers 0°, 5°, 10°, 15°, 35° of flappositions, while the ATR72 offers 0°, 15°, 30°. Since extending flaps affects aircraft pitch, automaticpitch trim for flap positions between 15° and 35° reduces the pitch forces felt on the control columns.

Being a long aircraft, the Q400 is very sensitive in yaw and pitch. “A minor annoyance when flying theQ400 is that the Yaw Damper has only limited governance over the rudder, which means that therudder has to be trimmed manually on every change in aircraft pitch or engine power setting”, saysMark. This problem, although present on the ATR 72, is not as severe.

The Q400′s flight deck sports large LCD screens, which offer considerable advantages on manydifferent levels. “The Q400 can be quite pitch sensitive, so having a large AI (Attitude Indicator) , hison the primary screen really helps when flying manually. The secondary screens can be used both fornavigation (NAV mode, in three different formats) and systems monitoring (SYS mode – electrical,doors, fuel, engines) which make monitoring the aircraft both in‐flight and on‐ground a breeze. TheEngine Display is, just like the other displays, clean and uncluttered, allowing us to detect and analyse


11 of 27 4/19/2014 23:32

The glass cockpit of the Q400. Image courtesy: Bombardier Aerospace

The ATR72‐600ʹs appealing glass cockpit. Image Courtsey: ATR

: PW 150A Turboprop Engine. Image courtesy: Pratt and Whitney

any problems with an enginein an instant. The screensautomatically dim themselveswhen it gets darker and can bedimmed manually as well,which is ideal for nightflights.”, says Mark, beamingwith enthusiasm.

The ATR 72‐500, features anElectronic FlightInstrumentation (EFIS), withtwo small CRT

screens per pilot. The remaininggauges are analogue. The ATR72‐600, which was certified by EASAonly in the July of 2011, is late tocatch up with a full glass cockpit,while the Q400 has sported this inevery model delivered since 1998. Aglass cockpit allows for a clean,uncluttered, organised and prioritizeddisplay of colour coded information.

The aircraft comes with a FlightManagement System, and forSiddharth Srinivasan, who is a TypeRating Instructor on the Q400, as wellas a line Captain at Colgan (servingContinental Connection’s routes),“The glass cockpit is good. Having flown both glass and steam gauges I definitely give glass the thumbsup. The FMS is a good step and very important to ensure full use of the capabilities of the glasscockpit.”

The PW150A engines on the Q400are controlled by FADEC (FullAuthority Digital Engine Control),unlike the PW127s in the ATRwhich are controlled by an EEC(Engine Electronic Control). TheFADEC provides automatic engineprotection against out‐of‐toleranceoperations, while reducing thenumber of parameters to bemonitored by flight crew. TheFADEC also provides

semi‐automatic engine starting, while also providing engine long‐term health monitoring anddiagnostics. With the number of external and internal parameters used in the control processesincreasing by one order of magnitude, a FADEC engine can deliver better fuel efficiency (relative toidentical non‐FADEC controlled engine).

Aircraft Sales and Production


12 of 27 4/19/2014 23:32

ATR 72‐600 rates are going to be ramped up to its limit, due to high demand for the type.

The ATR 72 was introduced in the October of 1989, with Finnair as the first customer. Born out of anATR42, in response to the need for a 70‐odd seat plane, the ATR 72 has in total delivered close to 410aircraft over 22 years. The most popular has been the ‐500 variant, selling about 290 airplanes since itsintroduction to service in 1997.

The Q400, although conceived much later, was born out of a similar requirement. With deliveriesstarting in 2000, 357 Q400s (including Q400 NextGen) have been delivered over the 11 year period.This on average translates to 32 Q400 deliveries per year, as against 21 ATR 72‐500s per year.

If these numbers are anything to go by, the Q400 has proved its popularity, though the geographicalmarkets of the Q400 and the ATR72 are almost complimentary to each other. The ATR 72′s presence ispoor in USA and nonexistent in Australia, while the Q400 enjoys a good representation all over exceptin Asia with only 3 independent operators cumulatively flying 32 aircraft: ANA, JAC, and PALExpress.

While ATRbuildsplanes inToulouse,sharingresourcesandtechnologywithAirbus, andis part of aEuropean

Consortium, Bombardier Aerospace is smaller, though only the third largest commercial aircraftmanufacturer in the world. This is enough to make the Canadian manufacturer significantly sensitiveto world economy and the health of the global airline business. In the April of 2008, With demand forturboprops shifting toward the larger models, Bombardier Aerospace had decided to focus on theQ400 by ceasing production of all other Dash 8 variants, leaving ATR as the only western producer of a50‐seat turboprop. In the Jan of 2009, Bombardier was mulling a boost in Q400 production ratesfollowing a delivery backlog of 113 aircraft. Eventually, this did happen. In the September of 2010,Bombardier Aerospace Chief Operating Officer Guy Hachey said that a regular stream of new, albeitsmall, orders for Q400s meant that production rates could be sustained. But in the June of 2011,Bombardier opted to reduce Q400 production rates while awaiting sales campaigns to materialise, afterfew prospective customers put their orders on hold.

For ATR, things are moving the other way with their next generation ATR 72‐600. Since launching the‐600 series programme in October 2007, ATR has received orders for a total of 165 ATR 72‐600 aircraft.Demand for the ATR 72‐600 has been very strong over the last 12 months due to its apparent attractiveoperating economics, proven reliability of the family of products, and latest avionics suite upgrade overthe ATR 72‐500. ATR delivered 51 aircraft in 2010 and is keeping production in 2011 in the region of50‐53 aircraft. ATR still plans to raise production next year to 70 aircraft, and possibly further in2013‐14 if the airframer is confident that the supply chain can cope.

While the sales figures are vastly different for the Q400 NextGens and the ATR 72‐600, Bombardierand ATR seem to share the same view on the future of the airline industry. In its 20‐year forecast, ATRanticipates a demand for 3,000 turboprops with a sale volume in excess of $20 billion, and is convincedthat 30% of the demand for 3,000 turboprops over the next 20 years would be met by a larger aircraft.Bombardier, in its 20 year forecast, anticipates a total demand for 6,100 aircraft in 20‐99 seat segment.


13 of 27 4/19/2014 23:32

Of the 6,100 aircraft deliveries predicted from 2011‐2030, 2,500 aircraft will be turboprops. Bombardieris quick to work on a bright future; a 90‐seat stretched Q400 is on the cards.

Conclusion

The number of Q400 aircraft flying today is indicative of the aircraft’s immense potential and proveneconomics. No further orders are being taken for the popular ATR 72‐500; the well selling ‐600 willreplace the ‐500 on the production line. With the ATR 72‐600 imbibing some good features of theQ400NextGen, such as LED lit cabin and a full glass cockpit, differences between the aircraft arereducing, though only cosmetic.

The Q400 and the ATR72 are two aircraft in their own leagues, beyond a true comparison. The Q400offers immense operational flexibility and unparalleled performance, while requiring only one aircrafttype for most missions. The ATR 72 wins over the Q400 in the operating economics, from the start tothe finish. The ATR 72 is less expensive to purchase, to operate, and goes out with a good resale valueto cost sensitive operators due to a high demand for the type.

Spicejet has based the Q400s at Hyderabad, serving 11 destinations. While the airline will start reapingthe benefits of a turboprop in its fleet from the 21st of August 2011, how the airline uses the Q400 to itsfullest, and the manner in which it complements its 737 fleet is to be seen.

It must be remembered, the Q400 was designed as a jet aircraft replacement; not as a mere turboprop.

Credits

Primary contributors who fly the Q400

Mark Brouwer

Mark Brouwer is a First Officer for Augsburg Airways,which is a Lufthansa Regional partner airline based inMunich, Germany. With a total of just over 1500hrs,around 1200 of which are on the Dash 8 Q400, he justhad his Airline Transport Pilot License “unfrozen”.

Siddharth Srinivasan

Siddharth Srinivasan isa Captain and TypeRating Instructor (TRI)at Pinnacle, which isheadquartered atMemphis, USA. His5000+hrs of experienceincludes time on theQ400, and the Saab340. Pinnacle fliesroutes for ContinentalConnection.

Primary contributorswho fly theATR72‐500


14 of 27 4/19/2014 23:32

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A K

A K is a senior first officer with Kingfisher airlines, flying the ATR72‐500 aircraft. With more than2200hrs of experience and an ATPL, she is set to move onto the Airbus A320 with a private low costairline in India.

A T

A first officer with a private airline in India, rated on the ATR72‐500. Despite being newly released, hehas an eye for detail and thirst for knowledge which makes him an valuable contributor. Yet, hehumbly adds, “I am an FO and have a long way to go”. [Photo removed on request]

Contributors who fly the ATR72‐500

B B

A commander with Kingfisher Airlines. She has a total of 3000hrs, of which 600hrs are in command ofthe ATR72‐500. She is the youngest captain in the country, having got her command at the age of 21.

C J

A senior first officer based out of Delhi, flies both the ATR72 and the ATR42 aircraft for a privateairline in India. He has 2500hrs of flying experience, and holds an Airline Transport Pilot License.

Note: All Indian Contributors’ names have been removed to protect their identity.

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Chuck

February 5, 2012 at 7:58 pm

How about doing the comparison with the EJETS. Using productivity and point to point networkwith longer distances

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Deep

February 18, 2012 at 10:28 am

Fantastic article, great detail – thank you.

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Capt Vishnu Unnithan

March 2, 2012 at 11:07 pm

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15 of 27 4/19/2014 23:32

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Congratulations for an excellent article. Well Done!!!

Anybody has any opinions about the comparative pilot fatigue experienced on the two aircraft atthe end of a hard day’s flying? and also regarding the relative spaciousness of the two cockpits.

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chowdhury j v

March 10, 2012 at 5:38 pm

very good analysis

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David

March 26, 2012 at 11:22 pm

My main complaint with turboprops is how poorly they handle turbulence, at least from apassenger’s point of view. I fly regularly on ATR‐72 aircraft with American Eagle between SJU andSTX and I can say without hesitation that passengers could do without the roller coaster reaction ofthe flight with every cloud that the ATR passes through. Granted, a jet may have more options inavoiding the less than smooth airspace, but I can tell you that passengers cringe at the thought offlying on them for that reason alone. In my many years of flying on them between STX and SJU, Idon’t think I can ever remember a single completely smooth flight. Now THAT would be somethingto address, at least from the point of view of the flying public.

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clay

July 23, 2012 at 7:15 pm

I agree 100% the ATR 72 is sensitive to rough air.

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Tim


The Q400 flies much higher than the ATR and hence above most of the clouds that, as you pointout, often generate uncomfortable buffet & turbulence. So in that sense, the Q400 hasaddressed the comfort issue.

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Amar Kothari

March 29, 2012 at 1:21 am

Very Intersting article….the author has described all in details with feedback from actual pilotstruely says the story of two turbo props. As India is such a vast populated country and as themiddle class is growing so fast with such an immense buying power almost 50 % of that middleclass is going to fly soon or in near future. New airports are being built and old ones are renovated

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the passanger traffic will increase drastically. Keeping that in mind and all the positive thingsdescribed in the article I am confident that the Q400 will out run any turboprop in his class.Congratualtions to Bombardier for job well done!

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Marcel

December 13, 2013 at 10:45 pm

…..the Q400 will out run any turboprop in his class….It is safe to say the Q400 is in a class of its own, really…..

good article, though!!

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Satyajitters

April 14, 2012 at 10:03 pm

I really appreciate the depth and research of the article. Just made my weekend

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Mark

April 21, 2012 at 1:00 pm

I was a first time passenger in a Q400 from Newark to Pittsburgh today. I loved the plane with oneannoying exception, noise. I was in seat 14B. Above my head and a little aft was a loud noise duringtaxi, takeoff, approach, and taxi. After landing gear was retracted noise went away. If the noise isnormal passengers should have been informed before hand. It was too loud. I will NOT fly in aQ400 until someone tells me what the root cause of the noise was and that it’s normal. I assume itwas hydraulic or APU both of which I don’t like.

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Jay

May 4, 2012 at 12:56 pm

It was most likely part of the hydraulic system which is turned on for the stages of flight youmentioned.

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Jayson

May 6, 2012 at 3:13 pm

Just came back from a vacation in Coron, Palawan, Philippines. Flew Manila (MNL) – Busuanga(USU) on Cebu Pacific ATR 72‐500. We had to wait for some time inside the shuttle bus parked onthe tarmac before we could board the plane since service personnel were using the same door usedfor passenger entry. Warm cabin before take‐off so much so that we had to use fans. The plane wasfull and the climb to cruise altitude took a really long time. Landing at the short runway of USU

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(1,200 m) was not a good experience; after initial runway contact the plane bounced up againbefore it could finally put itself into the pavement, shaking the entire cabin. Flew on Airphil Express(formerly PAL Express) Q400 on the return to MNL. Acceptable cabin temp before take‐off. Theplane was full but the climb to our altitude was pretty fast. Flying time to MNL was shorter byaround 15 minutes. The crosswind landing was definitely more comfortable to that in USU. I thinkthe placement of the main landing gear helps the Q400 make smoother landings since the cabindoes not directly take the vibration, and the wing flex might as well dampen vibration; whereas inthe ATR 72‐500 where the main landing gear are placed just under the cabin, vibration is morenoticeable. As to cabin noise, they were almost the same for me. Overall, the Q400 wins forpassenger experience, and I hope more airlines would be willing to take the Q400 into their fleet.

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keesje

June 9, 2012 at 5:46 pm

Very complete and nice written review, excellent job! I sense a slight preference for the Q400sbetter performance, from a pilot perspective. It seems the economics of the ATR are winning at thistime, as well as the enhanced cabin and cockpit of the ‐600s. Curious to know what BBDs answerwill be. They can’t sit on the hands saying theirs is faster..

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bigpoint

June 17, 2012 at 10:40 pm

ИЛ 96‐300 лучше!!!

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Cb

July 30, 2012 at 10:16 am

Hi I found this article very nice and interesting with few exception. I have been flying ATR42/72‐500 since last 4 years as a captain and was flying with kingfisher in India. Regarding thementioned speed during cruise in ATR I found it incorrect as it was mentioned in this article.VMOof ATR is 250 kts , and in ISA plus 15 degree average TAS u will get in ATR 72‐500 in average is250kts during cruise.yes u will reach 276 KTS in cruise but only in ATR 42‐500 and might reach inbelow ISA COndition in 72.In Indian condition for 72 only in decending phase.regarding the climbperformance in fully loaded ATR 72‐500 ,to reach FL180 from 3000 ft elev it takes almost 81 nm inISA PLUS 15 degrees c .After FL 100 it hardly gives u 700‐1000 feet per min climb and after FL 150hardly 300‐600 ft per min climb. So in term of climb performance it is far inferior to Q400.

Handling wise ATR 72 is not at all pilot freindly.work load for pilot is very high. Very hard to land incross wind and while raining.even during day time with more than light rain condition it is veryhard to land as ATR wiper is absolutely useless. It feels sometimes as its there just for the show.Ucan imagine landing in bad weather at night. As no hydraulics are avialable for primary controls,sometimes need good physical strength.Due to its climb performance ,max time u hv to fly through weather in monsoon period and duringlanding just watch out for pitch to prevent from tail strike.Air condition.. Not sufficient for Indian

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and subcontinent condition.OVER ALL it’s quite a challenge to fly ATR … But gets satisfaction after flight n loving it.

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Sahil

September 5, 2012 at 12:28 pm

one of the best aviation articles that i have read in a long time. Thank you for the insight.

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Napper

October 10, 2012 at 3:37 am

Hi

The sound heard during taxi, take‐off, approach is the PTU(Hydraulic Power Transfer Unit) it is asafety feature on the aircraft that transfers Hydraulic power between the two main systems in‐caseof a failure during take‐off or landing. It supply’s power to certain flight control and landing gear. Itis auto enabled and triggers when flaps move past 0 deg.

This is a generalization the PTU logic is quite complex. It makes much more noise when it called toprovide hydraulic power!! it is basically in idle mode during taxi.

I write the function test procedure.

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theflyingengineer

October 10, 2012 at 1:17 pm

Thank you!

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David Daniels


Of all the turboprops I have flown on, the best of the bunch to me, was the SAAB 2000. That reallydoes fly at jet speeds.Regretably it has been out of production now for a long time.

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Tom Martin


Unfortunately, the SAAB 2000 was way ahead of it’s time. It was unheard of to stretch a 1X2

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fuselage to 50 seats (proven viable with the ERJ‐145), and jet like speed with a turbo‐prop(proven viable with Q400).

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sony thomas


Sir,Just noticed this. Jet Air ATR taxied in kochi to parking bay with a single engine while the q400 ofspice jet used both engines for taxi while at mangalore.

i think i have read a story of delta airlines saving a lot of money by flaps up on taxi or single enginetaxi.

i it applicable for the q400?

just asked.

thanks.

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theflyingengineer

October 22, 2012 at 10:59 pm

Hello Sony,

Here is your reply from a Q400 pilot: Mark Brouwer, who helped me with this article:

At Augsburg Airways we always taxi with both engines running and the condition levers at maxrpm. That’s just company procedure, though, because I often see Austrian (Tyrolean) taxiing inwith one engine in 850 rpm. The difference in fuel flow is around 50kg/hr, but I guess it canmake quite a difference when it’s standard procedure on all flights.

We don’t shut down an engine completely, nor have I seen other companies do this. It’s quitecommon on the ATR, but on the Dash it would probably cause problems with maneuverabilitybecause of the wide track.

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sony thomas

November 1, 2012 at 1:25 pm

wow!!! thanks a milion…feels real good being able to communicate with a real worldpilot…..one doesn’t find many walking around (obviously they are flying, i guess)…..nice reply….thank you very much!

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deep

November 17, 2012 at 8:41 am

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just wanted to confirm from a pilot whether q400 is category B or category C aircraft . what is theapproach speed ?

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Asborn Webb

December 3, 2012 at 11:34 am

Just two days ago, I was responding to a post on facebook in relation to news clip that state LIAT islikely to upgrade its fleet to ATR 42 and 72 and not the Q400. As I observed most of us thatrespond to the post favors the Q400 over the ATR. LIAT have an all Dash 8 fleet of 3 Dash 8‐100and about 15 Dash 8‐300, so you can understand why we favor the Dash 8. However we allconcluded that from our observation on airport ramp and our experience as passengers in Dash 8aircraft we concluded that the Q400 is a much better aircraft for LIAT fleet renewal. Reading thisarticle have given me more love and favor for the Q400. Personally I will go for the flexibility andperformance of the Q400 then for the ATR 42 or 72 operating economics. Thank for this wonderfularticle.

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starjack22


First of all, i don’t think Q400s would work well for island hopping routes that LIAT operatesbecause the aircraft is too fast, this comes like having a jet to do the island hopping (rememberwhat happen to Redjet). Secondly, not most islands in the Caribbean region would supportQ400 because their airports have shorter runways. Even if LIAT was to get the Q400s it wouldhave to fly long routes especially between, Jamaica, Dominican Republic, Puerto Rico, Barbados,Trinidad and probably Guyana. This would just leave out the islands in between and rememberLIAT is a intra‐caribbean airline so it must serve all the islands. The ATRs whether 42 or 72 aremore economical enough to operate because they can island hop like the Dash 8 100s or 300sespecially when you talk about the ATR 600 series, the airline could save a lot of money inmaintenance and fuel when it uses these aircraft.The way i see it, the Q400s were really design to compete with regional jets like embrarer’sE‐jets and bombardier’s CRJs therefore the Q400s inherited the speed and economics close to ajet than a turboprop like dash 8 300s or ATR 42 and 72. I do like Q400s as well but if any airlinelike to operate routes with longer runways that’s the Q400s. If an airline wants to operate onshorter routes especially island hopping like Caribbean Airlines or LIAT at airports with shorterrunways, the ATR 42/72 is the way to go.

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starjack22


First of all, i don’t think majority of LIAT’s routes demands a Q400 because:1. The is aircraft is faster and larger than the Q300s2. There are some of the islands’ airports and runways can’t handle this aircraft and3. it’s not really design for island hopping.

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The Q400 is really design to compete with regional jets like embrarer’s e‐jets and bombardier’sCRJs on longer regional routes. The ATR 42/72s on the other hand makes more sense to operatebecause they can fly at a normal turboprop speed as a dash 8 100 or 300 and is still capable ofisland hopping. And the much advantage especially with the new ATR 600 series is that it couldhelp save the airline millions of dollars spent on fuel and maintenance making it moreeconomical sense to operate especially in shorter sectors. So there’s nothing wrong withCaribbean Airlines or LIAT choosing ATRs over Dash Q400s. I myself wish they would haveQ400s in their fleet but in a more economical outlook for in the Caribbean it may not be viable.

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Chris


Excellent article! Perfect!I just want to add information about ATR: spoilers are still activated on ground. I find itunconfortable (yaw effect) and dangerous when there is crosswind. (asymmetrical dragincreasement).Another parameter is missing in the performance analysis: the wind. Which is not in favor of slowaircrafts…Ex.: headwind 50kt (daily found…)Ground speed ATR 72: 226ktGround speed Q400: 310ktSo 37% faster!

Headwind 80ktGS ATR 72 : 196kt 1h31min for 300Nm cruiseGS Q400 : 280kt 1h05minSo 43% faster! 26 min less!

Often, this kinds of aircrafts are used to feed hubs. If you are late, connecting flights are missed…

Thanks again for this articleBrgds

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Stefin


Maldivian airways fly with Dash 8 300/200 aircrafts…. which is super and easy to handle.I do theload and trim for these flts its much easier compared jet engine loadsheets…

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Capt. Vibhooti Singh


Quite a detailed review and comparison between both the makes…

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Angus Clarke


Excellent article. It should be noted that although the list prices indicate a $7M difference, in realityits smaller, especially when the order is for multiple units. In my opinion the actual cost differenceis much smaller. (perhaps only about $2‐$3M.)

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Zacharias


Hi, one question:

Is it possible to fly the Q400 with lower speed than usual and save fuel through this?

If it should be possible: How much more fuel would the Q400 need compared with the ATR72,when operating with the same speed as the ATR 72?

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Tyrolean

January 10, 2013 at 1:18 am

Thank you for the great article. However you state that

“…with which the average cabin noise of 77‐79dBA is lower than that in an Airbus A318/319…”

which has to be a joke. I don’t care about the numbers but with thousands of hours as operatingcrew as well as a passenger on the Q400 I dare myself to know that it is significantly moreuncomfortable than any airbus narrowbody jet.

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29.

Doug Liser


Great article! Thanks.Just flew STS‐SEA on a Horizon Q400. Other than the noise, it was great. STS is tiny compared toSFO. It’s like a private jet experience. We held 400+ mph ground speed in both directions. The 2hr9min trip is only a few mins longer than a 737 from SFO. I’m a big fan of these aircraft for fuelefficiency. Swapping out jets for TPs on short routes could make more of a difference than all therail projects currently on the table.

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30.

Rashad

April 4, 2013 at 6:45 am

I would like to see you guys compare the old saab 2000 with Both Q400 atr 72/ 42 and even theDash 8 300 also and compare dash 8 300 Q300 the the atr 42 500

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24 of 27 4/19/2014 23:32

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AlexandreACW

April 23, 2013 at 6:22 pm

Remember Q400 crashed on USA around Feb.2009 with Continental Express colors and killing allon board.

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32.

kolorowa‐bielizna.pl

April 29, 2013 at 5:30 pm

I just couldn’t go away your web site before suggesting that I really enjoyed the standard info anindividual provide for your guests? Is gonna be back continuously in order to investigatecross‐check new posts

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33.

Krzysiek

May 19, 2013 at 5:02 pm

On polish LOT they call Q400 “square wheels” because of way in which it runs on ground. Shutterspassengers left and right, even at slow speeds during taxiing before start.

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34.

Behramjee

June 8, 2013 at 12:46 pm

how much does it cost approximately to operate a Dash 8 Q400 and an ATR 72 at full cost i.e.variable + direct + indirect

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35.

MB

July 6, 2013 at 6:38 am

I would like to know if anyone could inform me where I can obtain the fuel costs for Q400? Itwould also be great if I can get a breakdown of the operating costs. An approximate value shouldbe good enough, it will help me complete my thesis.Thanks in advance

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36.

Bharath Nahar

August 24, 2013 at 6:15 pm

spicejet has 15 Q400′s for its regional operations. The CEO of the airline put in his papers 18months in advance out of his 5 year term. The airline according to one of the pilots finds servicing

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25 of 27 4/19/2014 23:32

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the Q400′s pretty expensive. The spare parts of the aircraft are changed only after the pilots request3 or 4 times, to get it changed to the aircraft technical team. The airline being a low cost one spendsa lot of time and expense, in sending the pilots to canada for delivery of aircraft and tosweden/finland for simulation training.The other low cost airline, indigo gets all their aircraftdelivered in delhi.

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Claria

September 2, 2013 at 12:47 pm

SpiceJet sucks all Indian pilots are horrible, I was travelling from Goa . O my god what a hardlanding it was, and the maintenance sucks u will find mosquito, u will find windows are taped withpapers horrible airline I hv traveled

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38.

Peter Schmid

September 17, 2013 at 4:27 am

Thank you very much for an excellent article, very educational, including the comment section! Iwould love to learn more about both of these aircraft!

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39.

Felix

October 26, 2013 at 10:28 am

Fantastic comparison b/w the both.. Nice work.What about HQ ratings of the airplanes ?

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40.

Adrienne O/Neill


I am troubled by llymphedema of the arm, a complication that arose after surgery to my armpit forbreast cancer. i need to fly in a cabin with as close to normal atmospheric pressure as possible andwear an elastic sleeve throughout the flight. Does anyone know what the atmospheric pressure inthe cabin of these two planes would be at their maximum flying altitude?

Thanking you in advance.

the resident Mermaid

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Proud to Fly a Turboprop_ Q400 vs ATR72

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