The 1970s represents the high-water mark for general aviation in the United States – in several respects. Discounting the few years immediately following the Second World War, general aviation aircraft deliveries, according to the General Aviation Manufacturers Association trade group, peaked in the 1970s before beginning a precipitous decline. This decline can be attributed to any number of factors, ranging from a decrease in the numbers of active pilots to onerous product liability laws.
And, at the tail end of the decade, manufacturers concentrated their efforts on fielding products at the upper end of the spectrum – so as gross numbers declined, the average cost of delivered aircraft skyrocketed. Cessna, Mooney and Piper all fielded six-seat pressurised piston singles to capture sales at the high end of the general aviation market.
Piper’s offering was the PA-46 Malibu. Featuring a 310shp piston engine, it first flew in 1979. The first significant upgrade came in 1988 with the addition of a 350shp Lycoming TIO-540 engine. Less than 10 years later a Pratt & Whitney Canada PT-6 turbine was fitted and the aircraft rebranded as the Meridian. This was also fitted with a larger wing, to accommodate the fuel needed for the thirstier PT-6. In 2011, Piper upgraded the Meridian’s Avidyne avionics to a Garmin G1000 system. Then, in 2015, Piper fielded the M500; this first “M-Class” offering featured an enhanced Phase Three Garmin G1000 avionics suite.
Control feel and aircraft response were solid during low-speed manoeuvres
Jim Barrett/Piper Aircraft
The M600 was launched in 2015 to further raise the bar for Piper singles. Positioned at the top of its M-Class line, the M600 promised to deliver more refinement, speed and range. The M600 shares the same fuselage and cabin as the M500, but the similarities diminish from there. The flight deck is upgraded with a very capable Garmin G3000 suite. The M600’s PT-6 is flat rated at 600shp,100 more than the M500. A larger, more efficient 19.42m2 (209ft2) wing – 2.42m2 larger than the M500’s – is fitted, increasing fuel capacity from 644l to 984l. The engine and wing combine to give the M600 a maximum cruise speed of 274KTAS (457km/h), 14kt more than the M500. Most notably, the M600’s maximum VFR range (45min reserve) of 1,484nm (2,748km) is 484nm more than its stablemate’s. The M600 is more than 400kg heavier than the M500 and provides a full fuel payload of 298kg, 44kg greater than the M500’s.
While many M600 sales are upgrades from less-capable M500s, according to Piper's director of marketing, Jacqueline Carlon, several other manufacturers’ aircraft are cross-shopped. Perhaps the most obvious are the Daher TBM900/930 and the Pilatus PC-12. Interestingly, there are several light jets that compete in this market segment. The Eclipse 550 is at nearly the same price point as the M600, while a used Citation Mustang is also in the neighbourhood. The yet-to-be-certificated Cirrus SF50 may well also offer competition to the M600, with a good number of its sales sure to be move-ups from Cirrus piston singles. One dark horse may be the Epic LT. While currently available only in kit form, a certificated version is on its way. Recently FlightGlobal was invited to Piper’s Vero Beach, Florida facility to fly the M600 and see how it how it stacks up against the competition.
DAWN’S EARLY FLIGHT
My preview flight was conducted in two parts; the first part was a photoshoot and the second part dedicated to my more typical evaluation items. The M600 is single pilot certified and I flew both sorties in the left seat, with Piper chief pilot Bart Jones on the right. Our initial goal was to get some air-to-air shots at sunrise, so Jones had prepped the aircraft prior to my 0-dark-30 arrival. The M600 has a single entry door on its left side, aft of the wing. Two integral steps are mounted in the lower half of the split door. The preview aircraft (N403MM) was production representative, with two seats on the flight deck and four in a club arrangement aft. Access to the four passenger seats was quite good, but it took some contorting of my frame to slide between the forward seats and alight in the command seat. I am sure with a bit practice it would be second nature (just as getting into the F-16’s ACES II ejection seat without stepping on the seat was, in my prime).
Once seated, Jones turned on the battery, fuel pumps and ignitors before pushing the “Start Switch”. As the gas generator spun up, he set the condition lever to RUN as Ng passed 13%. After starter cutout the engine quickly reached IDLE. Once the generator was online, the vapour cycle air conditioner was turned on, providing much appreciated cool airflow. With the parking brake released, a small push of the power lever started the M600 rolling. Taxi speed was easily controlled with both wheel brakes and putting the propeller in the BETA range (aft of IDLE and forward of REVERSE). During the taxi I found the pedal-controlled nose wheel steering allowed me accurately track taxiway centrelines. As we taxied I followed our own ship position on the airfield diagram, a nice feature in the morning darkness. During the taxi, Jones set the electrically actuated flaps to T/O. With the Piper Seneca photo ship ahead of us on the runway Jones called “Ready”. As the Seneca pulled away, Jones advanced the power lever and executed the takeoff. With the gear and flaps retracted, Jones flew the initial join-up.
PLAYTIME
In position on the Seneca’s left hand side, I took control of the M600. For the next 50min we flew formation with the Seneca at bank angles up to 35º and speeds up to 140KIAS. While this was by no means an exhaustive evaluation of the M600’s formation abilities, it did serve to reveal its admirable handling qualities. I found the conventionally actuated control forces were well balanced in pitch and roll. Thumb actuated electric pitch trim deftly trimmed out yoke forces as the speed varied. Thrust response from the PT-6 was linear throughout most of the power lever’s range. Once placed in the right position, the M600 stayed there. Other than having to look cross cockpit and contend with the windscreen’s centre pillar, I found station-keeping to be a joy. After we peeled away from the Seneca and rolled out on course to Vero Beach (KVRB), I was reminded of a quote from Plato: “You can discover more about a person in an hour of play than in a year of conversation.” Flying formation is one of the most challenging things you can do in a single-engined light aircraft, and the M600 had just aced the first part of its exam.
I flew a visual approach to runway 30L with the flaps set to their full down LND position. Piper recommends an approach speed of 95 to 105KIAS, and I used the lower speed as my target. As can be expected, the large propeller made precise airspeed control a snap. At about 10ft I started the round out and pulled the power lever to IDLE. I did note that it took a significant amount of yoke back pressure to maintain touchdown pitch attitude as the airspeed slowed. Jones said this was normal, there being a large down spring in the elevator. Wheel brakes alone were used to slow for runway turnoff and taxi to Piper’s ramp.
After a short ground photo session, we taxied back out to 30L for the second half of the evaluation. Once cleared I smoothly advanced the power lever and set torque to its maximum continuous power setting of 1,575ft-lb. Acceleration was brisk and the available rudder easily countered the p-factor yawing moment. At 85KIAS Jones called “rotate” and the light M600 leapt off the runway. The landing gear was immediately retracted, with the flaps retracted passing 100KIAS and clear of obstacles. Piper lists a take-off distance of 716m (SL, MTOW) – markedly shorter than a Cessna Mustang’s 948m, and on par with a TBM 900/930.
The standard cabin layout with four seats in club configuration
Jim Barrett/Piper Aircraft
As time was limited we climbed to only 15,500ft mean sea level, well below the M600’s ceiling of 30,000ft. During the climb I engaged the autopilot and familiarised myself with the G3000 avionics. As with the other G3000 installations, I was impressed by its capabilities. The three interchangeable 12.1in displays were configured as two primary flight displays and a centre-mounted multifunction display. I especially liked the full-width attitude display indicator on the primary flight display. The ability to split the displays in a 60/40 format allowed several different Jeppesen charts to be presented, a nice feature.
Whilst level at 15,500ft, I set the power to 1,525ft-lb (fuel flow 350pph) and the aircraft accelerated to 197KIAS. On the ISA+15º day the resultant true airspeed was 255kt. At FL280 (std day) Piper lists a maximum cruise speed of 274KTAS, a tad slower than the PC-12’s 285KTAS, but well short of the TBM930’s 330KTAS. In addition to a higher speed, that higher altitude also gives a lower 324pph fuel flow than at our 15,500ft cruise point.
SAFETY FEATURES
While still at medium altitude we explored some of the M600’s safety features. One is its digitally controlled pressurisation system. The 5.6psi delta p system uses engine bleed air and gives a cabin altitude of 8,244ft at 26,000ft. Should a loss of cabin pressure go undetected by the pilot (above 14,999ft), the G3000’s hypoxia recognition system will be triggered and the autopilot’s automatic descent mode activated. There are also several other neat safety features embedded in the G3000 suite. The first is the “Blue Button” automatic level mode. Whether activated by a disoriented pilot or perhaps by a passenger in response to a disabled pilot, pushing the button will level the wings and return the M600 to level flight. While not quite the “get out of jail free card” that the Cirrus SF50’s parachute recovery system is, it does add another layer of safety while not adversely affecting hull insurance rates.
The M600’s Garmin GFC 700 autopilot also incorporates several flight control enhancements. The first is its underspend protection mode (USP). A flight director function, it allows the autopilot to remain engaged and prevent the aircraft from stalling should power be reduced below that needed for the commanded pitch state. The other is Electronic Stability Protection (ESP). Aircraft such as any fly-by-wire Airbus or Boeing 777/787 have features that are designed to prevent the aircraft from being over-banked. In the M600, bank angles less than 45º are unrestricted. If a bank angle in excess of 45º is held, a restorative force is applied to level the wings. If this force is ignored for more than 10s, the autopilot level mode will be activated, and return the M600 to wings level flight. This feature should help prevent inadvertent departures from controlled flight.
After trying out the Blue Button, USP and ESP features, I advanced the power and started a descent to see how the M600 behaved at 251KIAS Vmo. This speed is a significant improvement over the M500’s Vmo of 188KIAS. Both the M500 and 600 have the same Mmo of M0.55, and the M600’s increased Vmo allows for a larger safety margin at altitude and high cruise speeds. Additionally it allows for a faster emergency descent from high altitude. Approaching 251KIAS the red bar on the primary flight display airspeed tape alerted me to the impending overspeed. At 253KIAS an aural “Airspeed, Airspeed” was sounded. A series of short, sharp control doublets in all three axes (yaw damper off) showed the M600 was very stable. This solid control feel and aircraft response should engender confidence if the M600 needs to be manoeuvred at its upper speed limit.
Once below 10,000ft I slowed the M600 and set up for some good old-fashioned stalls. While I appreciate automated safety features, hand-flown slow speed flight can give you good insight into an aircraft’s handling characteristics. The first was in a clean configuration with the ESP feature turned off. Jones set the power lever to 150ft-lb of torque, to simulate IDLE thrust. In a 1kt/sec deceleration I gradually increased yoke back pressure to maintain level flight. At 80KIAS an aural “Stall, Stall” was sounded, with accompanying minor airframe buffet. Continued aft yoke pressure slowed the M600 to 72KIAS where a stable wings-level descent was entered. Aircraft response to small control inputs in all three axes was good. Relaxing yoke back pressure and advancing the power lever recovered the M600 to normal flight conditions. The second stall was in a landing configuration, gear down and flaps set to LND. The aural stall warning sounded at 64KIAS, with more airframe buffet than in the clean configuration. With continued aft yoke pressure the aircraft entered a nose-high descent, with the wings rocking +/-15º from level.
Again the aircraft was responsive to small control inputs, but the rudder was more effective at countering the wing rock than the ailerons were. Recovery to normal was again affected by relaxing yoke back pressure and advancing the power lever.
APPROACH SAFETY
Satisfied with the M600’s docile and predictable low- and high-speed handling qualities, before returning to Vero Beach we loaded the ILS10R approach at Treasure Coast International (KFPR). One nice feature of the M600’s autopilot is the ability to do a coupled go-around. As recent accident reports confirm, the safe execution of a go-around can’t be taken for granted. I engaged the autopilot and let it capture both the localiser and glide path. With gear down and flaps set to T/O, 575ft-lb of torque held our approach speed of 125KIAS with the M600 in a 2.5º nose-low attitude. While still well outside the Class D airspeed at 4,500ft mean sea level, Jones called for a go-around. I pushed the TO/GA thumb switch on the power lever. The autopilot smoothly pulled the nose to an 8º nose-high attitude. I smoothly advanced the power lever to about 1,300ft-lb torque and retracted the landing gear. Passing 100KIAS I retracted the flaps. The autopilot did an admirable job of climbing to and capturing our missed approach altitude of 5,500ft while still tracking the LNAV ground track. Jones added one caution about doing a coupled go-around – that advancing the power lever too rapidly can overpower the rudder’s ability to keep up with the p-factor-induced yawing.
Recovery to Vero Beach was via a visual approach to runway Y12R. As with the earlier approach, the M600 was a joy to fly on final. In the final portion of the flare manoeuvre, I was again taken by the rather large aft yoke pressure needed to capture and hold the touchdown attitude. While the M600 has reverse thrust available to aid in stopping, the dry conditions made wheel brakes alone sufficient to slow for runway turnoff.
PERSONAL SPEEDSTER
Certificated under the PA-46 type certificate, the M600 is a much evolved and far more capable aircraft than its nearly 35-year-old piston predecessor. While it does share a common fuselage and cabin, little else is common. A new wing, more powerful engine and class-leading Garmin G3000 avionics suite make it a viable entry into the niche left by the near-demise of the VLJs. With a range of more than 2,700km, the M600’s good runway performance and low direct operating cost make it a great fit for many owner-operators. While slower than the TBM930 and smaller than the PC-12, the M600’s typical out-the-door price of $2.85 million is $1 million and $2 million less than them, respectively. For the same amount you can buy a new Eclipse 550, but it has shorter legs and higher operating costs. While I personally would prefer a twin jet to a single-engined turboprop, for many the right choice will be Piper’s sleek M600.
Source: FlightGlobal.com
