Embraer Praetor 600 review: different by design

Reviews — 03.02.19 BY David Zara
 

In the few years since Embraer created its business aircraft division it has launched a number of innovative clean-sheet designs that are revolutionising the industry. The Praetor 600 is their latest disruptor.

Ever since Embraer upended the aviation community at the NBAA Convention in Orlando last year, with the shock revelation of two new fly-by-wire aircraft, the Praetor 500 and 600, I have been desperate to fly them. So it was with surprise and delight I received an invitation to go to the factory in São Jose dos Campos, and in short order found myself on my way to Brazil for an appointment with a Praetor 600.

 
 

Sitting on the apron, the 600 is longer than any of its competitors. It’s not the tallest, the fastest or the widest super-mid size aircraft, but in a crowded and competitive field it is the one with, by far, the most range. And at 3,900nm/7,223km it’s awfully close to Gulfstream GIV types.

The Praetors are made of aluminium and composites, where Embraer thinks it makes sense, which saves weight and reduces maintenance. The new winglets blend the best of both and are made of metal with composite leading edges. They are bolted on and can easily be replaced in case of hangar rash. The door is mechanically activated, avoiding the risk of having an accumulator fail. It’s the first aircraft to comply with a new requirement to be able to view the outside from the cabin before opening the door and so it has a little window.

 
 
 

Fly-by-wire

Like France, Brazil is a nation where engineering matters, and the fly-by-wire design (FBW) is superbly executed. The Praetor’s system is flight-path oriented, with no need for trim. You move the side stick and point the aircraft where you want and it goes and stays there. There are two modes, normal and direct. On normal mode all FBW protections are available, whereas on direct mode the jet behaves like a conventional aircraft. The system is designed to provide safety parameters in both normal and limit flight envelopes.

The normal envelope is built around 33 degree banks, pitch angle between plus 30 and minus 15 degree, Vmo and approximately 1.13 stall speed. The limit envelope has a limitation on approximately 1.05 stall speed, Vd/Md, a limited maximum sideslip angle and the maximum allowable load factor which is between -1 and +2.5g.

The system is so perfect that when making turns the FBW automatically compensates for pitch. It also saves a great deal on maintenance, virtually eliminating most, if not all, inspections and lubrication of mechanical components and cables. Cable tension checks are a thing of the past and inspections no longer require carefully choreographing seat and floor panel removal.

The single cylinder oxygen system supplies both passenger and crew and the only choice you need to make is whether you want the 77 cubic ft (2.2 cubic metres) or 115 cubic ft (3.3 cubic metres) cylinder. There are two masks in the cockpit and 15 more throughout the cabin, to cover all eventualities.

The waste system is a four-gallon tank and flush type vacuum system serviced from outside. The galley and lavatory water tanks are internally serviced and have a capacity of four gallons each. There are two heated drain ports when the aircraft is energised, plus an automatic water drainage system with the simple push of a button. It makes emptying the water easy on those freezing days.

 
 
 
 

Power point

The engines are derived from the reliable and proven Honeywell HTF7000 series. With dual channel FADEC there is plenty of redundancy and they are both quiet and environmentally friendly. At ISA plus 18 degrees Celsius they put out 7,528 pounds of thrust. Equally importantly, inspection intervals are on condition, saving operators money in the process. I loved the auto throttles, though I was at first taken aback by the engage button on the eyebrow. It was easy enough to adapt to this unusual location after a few minutes. The thrust reversers allow for performance credit for contaminated runways. There’s a time-tested Honeywell 36-150 APU, which has been in use for years with most aircraft manufacturers. In this version, it can be started up to 9,500m and provides electrical power up to that altitude and air conditioning and pressurisation up to 6,000m. I found it to be pretty quiet. The power system is protected from fire via a detection system and two bottles located aft of the aircraft. The whole jet is designed with common sense in mind and this philosophy can be seen in both large and small details. The GPU plug, for example, is angled so that inadvertent forward movement merely unplugs it instead of causing damage.

Embraer aircraft have military and regional airliner roots and it shows in their maintenance philosophy. For instance, most conventional aircraft would need 13 probes and static ports for data collection for the avionics. The 600 has only six to deliver the same information. This not only reduces the possibility of something going wrong, it also reduces the cost of maintaining those probes.

From an electric viewpoint, the aircraft is a 28 VDC plane with three DC 600 amp brushless generators mounted on each engine and the Auxiliary Power Unit (APU). The system is highly redundant with two main NiCad batteries inside the pressurised area of the plane and two backup batteries to power the flight control system and the pumps for the fuel system. Finally, there is yet again one more large airplane system for this super-mid. A Ram Air Turbine (RAT) system can provide power should all else fail. The system is sophisticated enough to not only power the aircraft, but it can actually recharge the batteries at speeds above 140 KTS. In line with the Embraer low maintenance philosophy, the RAT only needs to be checked at 24-month intervals.

The trailing link landing gear has ample travel to cushion even ham-fisted pilots landing on rough runways. More importantly, in case of a gear malfunction, the gear will free-fall thanks to gravity and aerodynamic forces, which are impervious even to climate change. Braking is dual channel Brake-By-Wire (BBW) via carbon brakes powering traditional brake pedals, and should the pilots get really lazy or braking conditions be dicey there is an autobrake system. It’s a very smart system that brakes before stowing the wheels during gear retraction. It also prevents the main gear wheels from touching down with the brakes applied. Which would be bad… Finally there is a Brake Temperature Monitoring System to keep track of temps during shorts hops. I found the brakes very linear and easy to use. There was none of the jerkiness of some BBW systems.

 
 

Fuelling flight

The fuel system is a simple single limit pressure fuelling system. Over-the-wing fuelling can still be accomplished, should it be necessary, but more importantly the system allows for defuelling as well. I loved the set-and-forget system. You dial in how much fuel you need and it stops when the limit is reached. There are two DC pumps per wing tank, and fuel balancing between the wings and the two fuselage tanks is automatic, though it can be overridden if necessary. The fuel pumps are brushless and essentially maintenance and headache-free. They are of the canister type and, following Embraer’s maintenance philosophy, they can be removed for servicing without emptying. The total fuel capacity is 15,986lbs (7,251kg), which is good for about 8:45 of flight with NBAA reserves. This gives you an idea how miserly fuel consumption is.

The wings are a work of art. Clean and with a 27 degree sweep, they and the rest of the surfaces are protected from icing via bleed air, like the big boys. Ice detection is automatic via a vibration probe. There are 11 flight control surfaces and they are electrically controlled and hydraulically actuated. There are three hydraulic systems providing great redundancy. Systems one and three are positioned aft of the fuselage to reduce cabin noise levels, while system two is located in the wing to fuselage fairing, to keep it segregated and everyone safe. This is a lesson learned from the DC10 flight that blew through its controls some years back. Number two is the one that powers the systems should there be an electrical emergency.

Though the weather was pretty nice the day we flew, there were some cells lurking out there. The MultiScan Technology weather radar has 320 nautical miles range thanks to a large nearly half metre-long antenna in the nose. I loved the reduced workload. It’s a ‘set and forget’ system and, as long as it’s dark, there isn’t anything to worry about. It also detects wind shear.

The 9.7 psi pressurisation system is capable of creating 5,800 foot cabin altitudes at FL450. Fresh air is plentiful and the entire cabin air is renewed every 3.5 minutes. A High Efficiency Particulate Air (HEPA) filter included in the price cleans the air.

I like the luggage compartment a great deal. Like all Embraer aircraft it’s large, unusually large for an aircraft of this size. Together with the forward cabinet and aft internal compartments the total luggage capacity is a grand 155 cu.ft and 1300 pounds.

 
 

And so to fly the bird

I had what was, without a doubt, the most thorough pre-flight briefing ever. The attention to detail is evident throughout the organisation. Daniel Bachmann, Corporate Communications Manager, Embraer, flew down from Florida to babysit me through the process and remained an interesting and gracious companion through a few days and some long dinners. Embraer then threw a lot of engineers my way led by Alvadi Serpa Jr. They spent two days going over the plane and answered each and every question I threw their way. Eduardo Camelier and Luiz Eduardo Salgado drew the short straws and had to endure my flying. Eduardo is a former fighter pilot and military test pilot, a position he segued into at Embraer. I am sure there is something that can frazzle him but I got nowhere near that threshold. The man is unflappably unflappable, but unlike most jet-jockeys he is also funny. Both he and Luiz have a sharp sense of humour and never miss an opportunity to laugh, even when it looked like we might all be upside down in two seconds.

Settling into the seat is easy enough and does not require yoga skills. Engine startup is child’s play. You flip a switch and the rest is done for you. All you have to do is to confirm the engines are on, because they are so quiet. Setting the cockpit for flight is quick and easy, but it was considerably easier with Eduardo sitting to my right. I think he could make the FMS sing if he wanted to. The nose wheel is actuated by steer-by-wire and it’s smooth. It’s powered by a hydraulic system driven by an electronic system and it’s beautifully calibrated. The range is 62 degrees right and left up to 10 knots (five metres per second) at which point the system gradually and wisely reduces the steering range. Disconnecting the system can be done from outside and allows for 170 degree free turns – enough for very tight manoeuvring.

Takeoff was uneventful with a smooth rotation followed by kick in the pants acceleration as I pointed the jet towards the sky. V1 and Vr speeds were manageable and quickly calculated by Embraer’s tweaked Pro Line Fusion system. The FBW knows the plane is in take-off mode or take-off law and behaves accordingly, reverting to normal mode once the take-off is complete a few seconds later. Take-off law assists the pilot by dampening the pitch mode on the aircraft to help set a proper angle. We climbed at a good clip until reaching the Embraer airbox reserved for testing. Steep turns were on the very steep side and I tried some abrupt direction changes. The 600 never even broke a sweat and responded in the spirit of the flight. The 600 can be flown both smoothly and firmly when needed. Our simulated engine failure was as non-eventful as you’d hope. The asymmetrical thrust compensation system did its thing and we flew straight and level, albeit with less oomph. Should the need arise to perform an extreme escape manoeuvre backed by FBW protection, this is the bird you want.

I have always said aircraft are more than the sum of their parts and this is where the Praetor shines. The word that came to mind when flying was fun. The controls are pleasant beyond words. They are solid, crisp and fast. This aircraft is meant to be flown smoothly and that is how I would fly it had there been passengers, but free of these constraints we could let loose and yank and bank to our satisfaction. The FBW gently reminded us that we were exceeding its design parameters and the system attempted to correct our ham-fisted ways, but we kept wringing fun and performance out of the jet.

Suffice to say we performed all the tasks called for in the flight test card, but saved some time for a couple of landings, and here is where the 600 shines brighter than most. Landings are smooth no matter how rusty you are. Braking, even when not using the auto-brake feature, can range from comfortable to hard – as in really, really short braking distances. I figured I used about 1,800 feet (550m) of pavement, even though I don’t know the plane and was unfamiliar with the airport. This was done by being firm, but without really stomping on the brakes. Pretty amazing. The SVGS system is perfect. There was no need to look outside and so I disconnected the auto pilot and kept my eyes inside for the first approach all the way to below minimums, with Eduardo at my side monitoring my progress. I was perfectly positioned for a landing when I transitioned to visual. My second approach was made without any instrument references at all and both resulted in near-perfect landings. The FBW automatically derotates the nose wheel when the mains have made contact with the runway. It’s a good system though I like having more control at this stage of flight. That said, I acknowledge the system does a better job than I possibly ever could.

 
 

Overall impressions

The Bossa Nova interior by Jay Beever and his team is gorgeous, and though it appears spartan at first, with its angular contours, it is surprisingly comfortable. The interior is difficult to describe because it’s an updated version of a retro-look. It made me think of Slim Aarons’ classic photos, but with modern day design touches like carbon fibre. A successful marriage of new and old, wrapped in creativity. It overturns traditional aircraft interiors in a progressive and inventive way and is thoughtfully designed with passengers in mind.

The range on the Praetor 600 will be a major factor when it enters the marketplace. The 600’s range is inching up on earlier generation long-range heavy corporate jets. From Dubai you’ll make Hong Kong in a heartbeat. From New York, Brasilia and Rome are within range. From London, New Delhi and Detroit are possible. The Praetor 600’s fully loaded range is greater than the ferry range of most of its competitors.

What would I change on the 600? I can only think of one thing. I am not crazy about the armrest position for the sidestick. I would have preferred an adjustable cradle for my arm, but save for that simple idiosyncrasy the 600 is one amazing machine. Embraer is a very unusual company. In only a few years they have created a business aircraft division out of thin air and rather than rely exclusively on converting existing aircraft to corporate use, they have birthed a few clean-sheet designs that are revolutionising the industry. There is little doubt the Praetor 600, the Legacy 500’s precocious child, is going to enjoy a very long life and have a very bright future in the marketplace.

 
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