Pilatus PC-6 Turbo Porter
Flight Test

Big Bird

A legend when it comes to hauling lots of kit in and out of challenging spots, there are no longer any Turbo Porters rolling off the Pilatus production line. Fitting one with floats just adds more awesome to an amazing machine…

There’s nothing actually wrong with a two-seat, Rotax-powered, side by side aeroplane. The odd one or two are a bit offensive, but they’re mostly ‘Tim, nice but dim’. Spot a few of them together and they look OK, add in a few flexwings and you can almost feel the three axis ‘real’ aeroplanes sit a bit taller, but put something that’s only the size of a PA28 or C172 anywhere near them and the best they can hope for is cute. Put them in the presence of a Porter on amphibious floats and they, along with anything like a PA28 or similar, become instantly invisible. The PC-6 Turbo Porter is Big, Tall, Square and very Yellow. It’s so friggin ugly it’s beautiful, so intimidating it pulls you in.

When this thing lands people come out to watch, and linemen rush out in golf carts like maître d’s fawning over an A-list movie star with a big appetite. If you don’t love a Porter you have no aviation soul, and if that’s the case, then even in these tough times I want you to cancel your FLYER Club membership and think about taking up cross stitching instead.

The first Porters came off the production line in Switzerland in 1959 and were powered by a big, gear-driven 340hp Lycoming piston engine. The last of the company’s stock of curves were presumably used up on the cowlings, as the rest of the airframe had to make do with straight lines and sharp angles, a design, if that’s not stretching the meaning of the word too far, that’s stuck with every one of the 600 or so airframes that have been built. It wasn’t too long before the piston engine was replaced by a turbine, initially a French Astazou II, then a Garrett and eventually in May 1964 the engine to which all runways seem to lead, at least in smaller turboprops, the Pratt & Whitney PT6A.

Vietnam War

The airframe/engine wing combination was designed to carry cargo or people in and out of short, rough strips with ease, a role in which it has excelled in pretty much every corner of the world.

It did make a brief appearance in the Vietnam War, where models built under licence by Fairchild in the US were equipped with a Gatling gun, four underwing pylons and a fuselage hard point for external ordnance. Thus equipped, and presumably without a trace of irony, it entered military service named the Peacemaker. It seems that low, slow and without protective armour was not a winning combination, and after a year in theatre all 15 aircraft went back to the US and were eventually sold to Thailand.

It’s not just the STOL capability of the airframe, engine and wing combination that has created the Porter legend, but the versatility. Want skis? No problem, you can have hydraulic retractable skis. Want to be able to drop parachutists? Yep, have a big sliding door on each side. Want to be able to chuck other stuff out? There’s an optional hatch in the floor for that (very 007). Stuff it full of cargo? Easy. Cram it full of people? Yep, some have been configured for up to 11. Want to carry heavy loads? Erm, well yes, but the useful loads are not quite as generous as some of the competition, are they? Yes sir, although that’s something it seems may have been overlooked once, twice or hundreds of times in the field. Allegedly. And then there’s a version with floats, available as straight floats (no wheels, cheaper and lighter with roughly half the weight penalty) or amphibious floats (with wheels, more expensive, heavier but with so much more versatility).

N66JL is one of three aircraft operated for humanitarian purposes by the Dieter Morszeck Foundation, and was most recently used to airlift injured people and bring in medical personnel, drinking water and food during Hurricane Dorian in the Bahamas. It’s one of the last PC-6s to be built before Pilatus closed the production line in 2019. It had the amphibious floats, which is just as well as we’d arranged to meet at Bartow, an airfield with a concrete runway rather than a lake or river. Thanks to its magnetic bulk and seductive ugliness, on landing the aeroplane drew the usual small crowd: linemen, maintenance people, pilots, hangers-on and a mysterious chap interested in perhaps buying it. Mr Mystery was taking an interest in whether it had NATO standard hard points under the wing, not something you often see in potential General Aviation aeroplane buyers. While the recently assembled group chatted about who knows what, I wandered up to the aeroplane for a bit of a closer look.

Yellow behemoth

Quite a few years ago I’d joined a pilot on a PC-6 ferry flight from Cyprus to Switzerland with the intention of writing about the aircraft. The pilot, who had a strange fascination and passion for handguns, would only let me fly in the cruise. Say what you like about the PC-6, but hand flying while in an airway and on oxygen at FL170 is both cold and tedious. I never did write about the trip, but I don’t remember the aeroplane, which was on wheels, being anywhere near as big as the yellow behemoth in front of me.

The big Wipaire 6100s lift the whole thing a couple of feet or more into the air, they feel big enough to be used as lifeboats on a cruise ship and they’re capable of displacing something like two and a half metric tonnes of fresh water.

Built from aluminium, each float has a baggage locker capable of taking another 50lb of baggage. Floats, amphibious or otherwise, are split into different sections, each of which can – and usually do – end up with some water in it. That’s pumped out at the start of the day or before each flight depending on their leakiness – 66LJ’s were dry, so no pumping required.

I thought it might be a bit rude to climb all over the aeroplane unaccompanied, so diplomatically suggested to the group that it was perhaps time to fly. Mr Mystery was keen to come along for the ride, so we settled on a shortish first flight with some water landings, after which we would drop Mr M back at the airport before heading out again.

I was going to be flying with Dave Hensch, a local seaplane instructor who runs Florida Seaplanes, and often works with the Pilatus’ owners. We talked through the exterior check, looked at the flying wires that tensioned the eight struts it takes to keep the floats and fuselage together while riding the waves, made sure the float hatches were secure and then took a look at the oil. Given the engine’s way out in front and probably 10ft off the ground, this is a bit of a precarious horizontal stretch, and one that I decided I didn’t need to experience first hand.

You board the aeroplane by first climbing onto the floats, and as if to emphasise the height, there’s not one but two cut-outs to help you get up there. Once on the float, two more steps take you high enough to get in through the front cockpit door, or the rear sliding door. This particular Porter is equipped with a stretcher and two seats, but the configuration can be changed fairly quickly. What goes in the back and how it’s arranged is all very interesting if you’re trying to figure out how to make money from your expensive asset, but let’s face it, we’re really interested in the cockpit and going flying.

Sitting in the cockpit there’s no doubt that this is a utilitarian aeroplane. There’s no plush Alcantara, no deep pile carpets, no cup holders, what you get is what you need and not a lot more. The PC-6 is the only aeroplane I know to have what looks like a small, flat parcel shelf in front of the two cockpit seats. It’s home to the throttle quadrant, the emergency trim, pens, iPad, charging leads etc. Unusually the stick sits under this ‘shelf’ so when you’re flying, most of the time it’s out of sight, which is a bit strange. Avionics is a Garmin G950, which is basically a G1000 without the integrated GFC700 autopilot or audio panel. This aircraft also had a Bendix King ADF and a S-TEC autopilot fitted, but I managed to avoid touching either, preserving them for their overdue display in an avionics museum somewhere.

Once we’d briefed the normal stuff (such as, how to get out in a hurry, don’t fall, it will surely hurt) it was time to clear the area and get the engine started, which basically involves lighting and sustaining a fire inside the turbine engine. This is accomplished by the starter blowing large quantities of air through the engine, turning on ignitors and introducing fuel in two stages. Done correctly, and you get a self-sustaining flame surrounded by a protective sheath of air that’s ready to power your aviating dreams. Get it wrong, and you get very big invoices and maybe an email that’ll only be powering your CV writing skills. Once everything’s up and running and the prop lever is set forwards, and the fuel condition lever set to low or high idle, you’re left with just the throttle to worry about. I continue to be surprised that expensive and sophisticated engines like this aren’t FADEC controlled and therefore protected, but they’re not and it seems to work, so clearly I need to get with the plan.

Dave’s main concern was that I’d put in too much throttle and over-torque the engine (with potentially similar results to a start done wrong), so I made sure that the torque meter didn’t get close to the 47.3psi max.

The parking brake…

The plan was to go and do a few splash-and-goes on a local lake, but both Bartow and our chosen lake sit in Class D airspace. A quick chat with the controller got us permission to fly as many ‘patterns’ at the lake as we wanted if we kept it below 500ft. Time to taxi, so off with the parking brake. Ah, yes, the parking brake. Here we are in this 620hp beast with a max take off weight of nearly three tonnes and the parking brake is operated by pulling what is little more than a piece of cable you’d worry about if you were using it to hang a small painting on the wall. Fearful of breaking the cable I delegated the task to FO Dave and headed for the runway. My right hand’s on the throttle and my left on the invisible stick grip under the shelf. In stark contrast to the parking brake wire, the stick top grip is huge and my thumb is at a bit of a stretch to get to and operate the stick top trim. I don’t know if Swiss pilots have large hands, or if someone mistakenly ordered giant stick tops, but blimey…

The front wheels are fully castoring, so differential brake is needed to get a turn started, plus a bit of anticipation is needed to get the aeroplane to come out roughly on a desired heading. Forward visibility is great, although with the long nose protruding for about half a mile, I guess it might be possible to lose sight of something under the aeroplane.

There’s no engine run up with a turbine, but we did pay particular attention to the trim position. The fact that there’s a bloody big emergency trim and a big emergency trim disconnect right in front of you should be a hint that the PC-6’s trim is more than powerful enough to spoil your day, should you take off grossly out of trim. That and the emergency brief taken care of, I line up, set the flaps and gently advance the throttle, keeping one eye on the runway, one on the ASI – and another on the torque gauge. This was a gentle departure, and somewhere around 50kt I rotated and let the aeroplane accelerate to climb at about 80kt with the gear and flaps up.

My immediate impression was that the huge floats and perhaps the optional and full external fuel tanks were making the handling a bit, erm, steady. I’ve flown a couple of aeroplanes that had me wondering if the stick was connected to the ailerons by a few strands of tired elastic, the Porter had none of that vagueness. Things happened when you asked for them, and they happened straight away, it’s just that the rate of change wasn’t overly fast, at least without getting a bit aggressive with the controls, and a few hundred feet off the ground and seconds into my first flight wasn’t really the time or place. We head straight for the lake and orbit a couple of times, partly to get a feel for the aeroplane but also to have a scout for wind direction, wire hazards, boaters, ‘gators and fisherman. Dave demos a landing, and hands back as we turn crosswind. The plan is to approach at 75 to 80kt, land (or should that be water), climb away and do it again as many times as we can in the length of the lake.

Downwind we check the wheels are up. Landing an amphib on water wheels down is worse than hot starting and over-torquing. It will spoil your day or maybe more.

As it happened, conditions were great, the PC-6 was stable and easy to fly, and I managed to fit in four splash- and-goes in the length of the lake.

The next would be the water equivalent of a stop-and-go, except on the water that’s more like a land, drift-a-bit-and-go. When the floats touch the water, bringing the power fully to idle and the stick all the way back gives a fairly rapid deceleration, then a lever between the seats drops the water rudders and that gives you much better control. We had light winds so feigning accuracy wasn’t too difficult, but in a decent breeze I imagine that more skill than I currently have would be required to dock with any precision.

Taking off, the all important trims and undercarriage position are checked, power is set (taking care not to over-torque), the stick held fully back and the water rudders retracted. Once the nose has finished rising the stick comes forward a bit to get on the step, then a combination of light back pressure and perhaps slightly lifting one float gets you unstuck and climbing away. The combination of excess power, a light breeze and a long lake conspire to make me think that I’m half competent and we head back to the hard runway to drop off Mr Mystery. This time we definitely want the gear down (it’s a wheel-shaped handle underneath the PFD), but best not leave it too late as the extension speed is much, much slower than the aeroplane’s roll rate. All four wheels are eventually confirmed down by the gear lights and by a voice continually saying ‘gear down for runway landing’ and I approach at, yep, 75-80kt. I had a bit of a crosswind for landing, and although there’s a big slab-sided fuselage and a couple of humongous floats, the four landing gear and six tyres made it a lot easier than it would have been in the tailwheel version.
   
With our ride-along ‘interested party’ offloaded, we headed out to an even larger lake for some photos and some more water work. The second flight is always easier than the first, by now my thumb had become used to stretching for the trim and my brain no longer needed three eyes to keep everything in its place. It would be silly to say that after one short flight I was completely comfortable, but what had started out as a big, beautifully ugly yellow beast had got just a little bit smaller.

Extraordinary feats

A 15 minute flight to get to the lake was enough time for me to figure out that if you’re going to cruise at low level you can expect to get about 100kt IAS for a fuel burn of about 50 (yes FIFTY!) US gallons per hour. The higher you fly the better it gets, and you can choose between keeping the same indicated airspeed and burning about 35 gallons up at 10,000ft or keeping the same fuel flow and seeing about 140kt IAS. No, you’re right, this aeroplane isn’t about going a long way fast, it’s about going a fair distance (and if you top off all of the tanks, including the underwings you’ve got close to 300usg), and then performing extraordinary feats when it gets there.

Sadly, with the PC-6 now just a Pilatus production memory, if you want one you’re going to have to look through the classifieds. You could probably pick this one up for just north of $2m, and you’d have a very capable and almost brand new aeroplane. Although the fuel and maintenance costs are going to be punchier than your average LAA Permit aircraft, the really frustrating part would be having a gloriously brilliant amphibious aircraft in a country that’s so anal about aeroplanes landing and taking off from water. If I had one in my hangar it would either have to be on wheels, or I’d find a country with a broader outlook.

Record Holder

Over the years the Porter has acquired quite a few records, some impressive, some that raise an eyebrow and some that leave you wondering… WTF?

By far the most impressive was the highest landing for a fixed-wing aircraft when a ski-equipped, piston-powered PC-6 nicknamed Yeti landed at 18,864ft on the Dhaulagiri glacier in Nepal. You might wonder why it doesn’t also have the record for the highest take-off? The departures didn’t go quite so well, and a mishap means that the damaged aeroplane remains in situ to this day.

Then there’s the 1969 record in which an Astazou engined PC-6 was flown to over 44,000ft, and while we’re discussing heights, an Australian pilot set the ‘distance in a straight line’ record for the category by flying a Porter at 27,000ft at -41°C, covering 2,102nm.

The Porter also holds the record for the most take-offs and landings in 24 hours, with Tom Bishop racking up 424 in 21 hours.

Tech Spec

Performance

Max speed (Vne) 151kias
Max cruise speed 139kt @ 10,000ft 139kt @ 10,000ft
Stall speed (clean/full flap) 53kt/49kt 53kt/49kt
Take-off distance water 1,240m
Landing distance water 825m
Rate of climb 965fpm
Range It depends!
Fuel burn 190 litres/hour @ sea level @ 100ktas

Weights and loadings

Seats Up to 11
Max take-off 2,772kg
Empty 1,801kg
Payload 971kg
Payload with 3hr fuel 562kg
Baggage Lots and lots and lots…
Fuel capacity 390usg with optional underwing tanks

Dimensions

Wingspan 15.88m
Wing area 30.1sqm
Length 10.92m
Height 5.1m

Spec

Airframe Aluminium
Engine Pratt & Whitney PT6A-27
Max power 620shp
Propellor 101in diameter, three-blade Hartzell aluminium, fully reversible
Avionics Garmin G950 Garmin G950
Undercarriage Wipaire 6100 amphibious floats
Manufacturer Pilatus Aircraft Switzerland www.pilatus-aircraft.com
Price Used examples vary. The example flown would probably cost $2.1m, but older wheel versions are significantly less
More info www.pc6.net
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