The basic model in Curtis Pitts two-seat biplane series is as good today as it was on its introduction in the sixties
Dave Cockburn would, I’m sure, have met with the approval of the late, great Curtis Pitts. I am betting that Dave would have been the kind of owner Curtis had in mind when he embarked on the laborious process of persuading the FAA to grant the S-2A a Type Certificate. Hitherto, all Pitts Specials had been homebuilts. Curtis wanted his design put into production so that more people could fly it; he knew he was on to a good thing.
Dave is 66 and for the last eighteen years has operated his Pitts S-2A from a farm strip. I landed it there a few years ago and won’t forget the experience quickly, since the strip is rather small for the aeroplane.
I ask Dave how he came to buy his S-2A. “I saw it advertised by Richard Goode, who’d sold the owner a Sukhoi,” he explains. “It was on the Italian register and still in Italy.” Dave had it transferred to the N-register and flew it to the UK over the Alps. The flight wasn’t without incident. “Near Basel the weather clamped in, so I landed there and came home for a week before returning to complete the journey.”
Not bad for someone who had only got his licence two years earlier, but then Dave is a rugged character with an interesting history. He has had many different jobs, including working as a car mechanic and a sound engineer, before becoming a roadie. “I would never have been able to afford learning to fly, let alone the Pitts if I hadn’t founded a trucking company for bands at exactly the right time,” he says. “It was just when raves were becoming fashionable and the organisers had money to burn. Sometimes they’d have one of our trucks going round the M25 all night, trying to get to a venue without the police knowing... not that it was illegal. We always got paid and they could afford to be generous.”
Currently he flies thirty hours a year, mostly with his fiancé Jacky in the passenger seat. Last year they flew to France, the Channel Islands and the Isles of Scilly. The year before they toured the Highlands and Islands. He isn’t a competition pilot, but he enjoys aerobatics and likes to enliven flights with a loop and a roll. “I just love the feel and the handling,” he says. “And I love the fact it’s a biplane. It keeps me on my toes, but the S-2A is a very practical aeroplane.”
If I remember rightly, another ‘late, great’, James Gilbert, Pilot’s one-time publisher and editor got the sack when working as a staff journalist for Flying in America because he had gone to visit Curtis Pitts without asking anyone. (I imagine he thought they’d say no.) Curtis was a crop sprayer who decided in 1943 to build a tiny, streamlined biplane. And as a result of that visit, James told the world the story of how Curtis had become so pissed off with the four-year slog to Type Certification that he hid the words, ‘F*** the Feds’ in the first letter of each paragraph of a document he submitted. The bureaucrats either failed to spot the insult, or they decided to overlook it.
Today Dave has offered to fly his S-2A to Little Gransden, where I can land it with confidence, so that we can make it the subject of a Pilot flight test. My acquaintance with Pitts Specials started in the late 1980s, when I bought Neil Williams’s old Pitts S-1S, G-AZPH?the second to fly in the UK. Later, in a group that included Alan Cassidy and Nick Wakefield, we traded it for G-BKDR ? a more modern and greatly modified S-1S. In 1990 I won the British Advanced Championship in ’DR and came second at Unlimited in a Dutch contest?then the group moved on to monoplanes.
I first sampled an S-2A when a group member damaged ’DR the day before an Advanced-level contest. Alan offered to let me enter in his S-2A. I had one practice flight before the contest, and managed second place. Compared to the S-1S, the S-2A felt heavy, both on the controls and in a tendency to lose height between manoeuvres, but otherwise it flew like an S-1S. Its disadvantages were largely offset by its greater size, which meant that positioning close to the judges wasn’t so critical.
I’ve flown several two-seat Pitts Specials since then and always enjoyed the experience. However, the later models with more power (the S-2B and S-2C), while considerably more capable in aerobatic contests, struck me as having lost something when it comes to handling. And the S-2A would be cheaper to buy second-hand (being older) and more economical to operate. So altogether, I’m looking forward to getting re-acquainted with the type.
The tandem seats have a warbird feel about them. You have company in the aeroplane, but at the same time, you are on your own, communication being limited to the intercom. You can’t see each other’s faces like you can in side-by-side two-seaters, nor can you point to things.
Climbing aboard after a long absence has for me a familiar feel. You put one foot on the lower wing root, reach up to the handhold in the top wing, hoist a shoe over the steep side, step onto the seat and down into the cockpit. For a Pitts newcomer, the cockpit seems deep and high ? a bit like stepping into a well?and once the front seat has someone in it, your main view is of the back of their head. The military theme continues in the footwells above floor level and the exposed steel tube fuselage with its outer cladding of aluminium sheet and fabric. It’s all very functional and the siting of some of the controls and their labelling seems a little perfunctory. There’s a substantial centre console sprouting from the footwell between my calves, holding the radios and other secondary bits and pieces.
Dave and I strap ourselves in?a five-point harness including a negative-g strap coming up from the floor, plus a two-point secondary harness for each of us. I then reach up for the big canopy and swing it down, then punch it forwards. “Give it some welly,” says Dave. Pushing sideways a stiff lever at the top locks it. In the front seat, Dave can see the locking catches and confirms that they’re secure. If they weren’t quite settled, at full throttle the canopy would jettison itself, causing much heartache.
I look for everything I’m going to need, then get ready to start the engine ? power switch up, intercom on, fuel tap on, mixture fully lean, throttle cracked, pitch fine. I shout “Clear prop!” and, holding the stick back with my toes pressing on the brake pedals, twist the start key. The engine cranks, lifeless for several seconds, “Keep cranking, Nick, she’ll start” and without warning bursts into life. I push in the mixture control and set rpm to something sensible.
Now that the engine’s running, the tension I was feeling a moment ago has turned to a growing feeling of excitement. My thousand-plus taildragger hours are largely in the past and I’m probably rusty. I haven’t flown a taildragger for six weeks and that was a Super Cub ? much tamer than a Pitts. I’ve made perhaps twenty tailwheel landings in the past twelve months. I should be fine, but there’s a niggle of doubt. The engine instruments are soon in the green and we run through the pre-takeoff checks, including cycling the CS propeller via a rather odd lever to the left of the instrument panel.
After waiting for the cameraplane’s Gipsy Major (it’s a Chipmunk piloted by the ultra-reliable Bob Morcom) to reach its operating temperature, we taxi in close formation out to the runway, the Chipmunk leading. I weave from side to side to keep the other aircraft in sight. Taxying the S-2A is pretty straightforward although, with so much spiral airflow and a rather short fuselage, rudder alone won’t work at times and you do need to supplement it with toe brakes fairly smartly to avoid a leisurely ground-loop. The view isn’t bad if you weave and, while you should keep the stick back at all times, the undercarriage is set far enough forward that you don’t need to worry about lifting the tail and a prop-strike.
We line up, the Chipmunk begins its takeoff run and, after waiting three seconds, I smoothly go to full throttle, simultaneously pushing the control stick fully forwards. We accelerate fairly smartly, twisting left ? but a jab of right rudder sorts that out ? and I’m utterly unable to see ahead for a slightly anxious couple of seconds before there’s enough airflow for the tail to lift. Now I can see over the nose, confirm that we’re pointing in the right direction and that there’s no danger of our overtaking the Chipmunk.
I have no attention to spare for the ASI, because the Pitts is squirreling a little. I am probably over-controlling on rudder. The controls are lightening up, the aeroplane coming fully alive. I see the Chipmunk’s wheels separate from the grass, give ours another second or two for luck and ease back on the stick. We bounce gently and then climb away, accelerating towards the Chipmunk until I throttle back. Soon both aeroplanes are climbing at the same rate and maintaining separation and I’m able to open the throttle and draw alongside.
By now I feel completely at home in the S-2A and my earlier anxiety has gone. It’s great to be sitting behind a pair of biplane wings again, power in reserve under my left hand, with my feet splayed on rudder pedals and my hand on a joystick. The controls aren’t light or heavy, just ‘right’, and there is plenty of control authority if I want to do anything dramatic. At the same time, light, precise control of the kind needed when cameraman Keith Wilson points up or down or waves me closer or further away is at my fingertips. The changes he commands involve moving the aeroplane just a few feet and holding it there, and the S-2A is one of those wings-at-your-back, think-it-and-it-does-it aeroplanes...
Which is pretty amazing when you consider it. People had begun switching from wooden to steel-tube fuselages in America soon after Anthony Fokker showed the way with his Fokker DVII in the Great War. Even so, aerobatic biplanes between the 1920s and the 1940s underwent a slow development. Compared with this little beauty I’m flying now, aircraft like the Stearman and the Great Lakes are primitive, mediocre performers in aerobatics. Only the Belgian Stampe and German Bücker Jungmann come close, but even they fall short. Curtis Pitts designed some very clever features into his Pitts Special. He began drawing the design as far back as 1943.
Firstly, he realised the importance of streamlining. It’s this that made the Pitts Special an aerobatics contest winner even though it was competing with monoplanes with no external struts or bracing wires. Instead of two interplane struts with diagonal bracing wires, he used a single I-strut. In place of two externally-braced vertical N-struts to hold up the wing centre section, he slanted the Ns inward to make a pyramid and inverted V. He kept the fuselage short and the wing area minimal to reduce drag and he used a low-drag engine cowl and flat-four engine in place of a radial or four-in-line. There’s genius in the wing design: a one-piece, swept back top wing combined with two un-swept lower wings. Wing sweep improves stability and flick-roll performance, but it makes it harder for judges to assess whether a competitor is flying an accurate 45-degree climb (for example), so he gave the aeroplane both. The un-swept lower wings have their trailing edges aligned with the pilot’s eyeline, making accurate flight easier from the cockpit.
The ailerons are superb, producing an excellent roll rate with little adverse yaw, and the slave link to the upper set is another low-drag feature, a single rod. The use of push rods and clever design keeps control play to a minimum.
The second consideration that has enabled the Pitts Special to stand the test of time so well is its basic, rugged construction. It’s immensely strong, yet light and simple enough for amateurs to build. Maintenance, compared with other 1940s biplanes, is un-complicated. Everything about the Pitts Special is well thought out, and seems to have been right from the beginning.
One possible downside to flying close formation in a biplane is the number of blind spots. I spend parts of the photoshoot formating on a component of the Chipmunk, the rest being hidden. Local turbulence means that the Chipmunk is constantly bobbing about, which might have felt uncomfortable ? it doesn’t, since the S-2A is so controllable.
So we sail through the photoshoot without difficulty. This includes the first half of a formation loop and me drawing ahead and rolling inverted and holding the S-2A upside-down while the Chipmunk draws up close for a photograph. One standard feature of the S-2A ? which is factory produced ? is full inverted oil and fuel systems, so we could hold upside-down indefinitely. It’s not uncomfortable, and if I chose to, I could trim elevator so that I wouldn’t need to push on the stick as I am doing now. The push force isn’t much though, since the S-2A has a symmetrical wing-section. This means that upside-down; the aeroplane isn’t especially nose-high, making it easier for the judges to tell if your slow rolls and four-point rolls are truly axial. In the Tipsy Nipper, for instance, or the Cessna Aerobat, both of which have flat-bottom wings, the nose has to be well above the horizon, which looks ugly.
The formation loop begins with the Chipmunk diving to gather speed. It begins to pull up at a speed that is ludicrously inadequate for the S-2A, which is heavier and also has a higher wing loading. I follow, and despite our low entry speed, am able to steer laterally to keep the right distance for the camera. I can feel the combination of a 200hp engine and an efficient CS prop sustaining us as we approach the vertical, even though gravity is winning by now and we are running out of energy. I bank away left just as the S-2A begins to sag and torque-roll and we finish nose-down with a last sight of the Chipmunk heading away under our belly before gathering enough speed for me to pull gently out of the dive.
Eventually Keith says he’s got all his photographs and we head back to Little Gransden. Following Dave’s directions, I set the rpm at 2,500 and the manifold pressure at 25 inches. In this 1981-manufactured S-2A, which has 1,300hr on airframe and engine, this produces a 120kt cruise speed. After adjusting the mixture, we are using nine gallons an hour, giving us a two-hour endurance from full tanks, leaving half an hour’s reserve.
The back seat of the S-2A isn’t quite as good a platform for navigating as sitting in a Cessna or PA-28, because there is no view ahead. In clock-face terms, what you get is quarter-to to five-to; and five-past to a quarter past. However, if you do want to look ahead you need only twitch the powerful controls into a gentle sideslip. Most biplanes have this drawback, because you solo them from the rear seat and have the nose and wings ahead of you. It’s something you quickly get used to.
There is some stability in the S-2A, but not much and you really need to fly it most of the time. It bores through the air smoothly, though, giving a comfortable ride, especially when compared with its little brother, the S-1S, which tends to dance about and can also be a noisy, hot little box with 180hp just in front of your feet.
The Rothmans Aerobatics Team, which originally flew a fleet of Stampes, converted to Pitts S-2As and covered considerable distances in them. I imagine the displays were similar, but the fifty per cent increase in cruise speed must have transformed the cross-countries. Their S-2As had open cockpits, incidentally.
Once safely back at Little Gransden, having previously cleared it with owner Mark Jefferies, I climb to 2,500ft to sample some aerobatics.
A good entry speed for a loop seems to be 150kt. A gentle dive gets us to that speed without losing much height and up and eventually over we go. All very pleasing and simple. I follow that with a stall turn with the same entry speed. The S-1, I remember, was tricky to stall turn, so I am on my mettle. On the way up I compare wingtips on both sides against the horizon and realise that I’m yawed a good five degrees left, so the up-line is marred by a corrective wobble. I arrive at the top properly vertical, though, and by now I’m holding quite a lot of right rudder against spiral airflow (still at full throttle). Swapping to full left rudder produces a nice, clean reversal and now we’re pointing straight down and accumulating speed.
My next manoeuvre is a half-reverse-Cuban, with a half roll to inverted on a climbing 45-degree line. The half roll is delightfully brisk and we’ve loads of energy left afterwards. So I prolong the inverted 45-degree climb before gently pulling through to complete a loop.
I keep the loop big in order to reach level flight at 160kt for my next manoeuvre, which will be a quarter-vertical roll. I have time to compare wingtips and get absolutely vertical before the quarter roll ? delightfully brisk again, but not disorientatingly so, as it would be in an Extra ? and then bags more time still heading up vertically before increasing right rudder and a general waffly-ness tells me its the moment to rudder over into another stall turn. A half roll on the downward vertical is brisk, so we lose little height before pulling level at 160kt. I’m now going to attempt an avalanche.
We pull up and as the S-2A approaches inverted, I push hard on the left rudder and pull the stick all the way back to induce a flick roll. I’m evidently not vigorous enough and we rotate rather lazily, although there does seem to be auto-rotation, because when I apply opposite rudder with a quarter-roll to go, I’m only just in time to stop it and come out on line. That flick roll at the top of a loop is the only auto-rotative manoeuvre I’m going to fly today (out of consideration for my passenger), but it suggests to me that the S-2A is rigged with a forward centre of gravity. The resultant resistance to stalling would make it tricky in competitions for flick roll and spin manoeuvres, but also safer as an aerobatic trainer and tourer. Given that it’s a factory produced aeroplane with a Type Certificate obtained in 1971, a forward C of G and reluctance to stall is only to be expected.
After a half-loop, half-roll ‘Immelman turn’, I finish my sequence with a quarter-turn rolling circle to line us back up with the runway and a four-point hesitation roll. The rolling circle is tricky, but promising and the hesitation roll, pure joy.
By now we’ve dropped down by a thousand feet, which is pretty modest considering how many manoeuvres we’ve flown. It’s also an indication that the S-2A has enough power for Standard and Intermediate contests, although I imagine it’s somewhat under-powered for Advanced level. It’s also got about the right amount of power as a teach-yourself aerobatic trainer, or for learning with an instructor.
I’ve subjected Dave to enough aerobatics, and it’s time we brought the sortie to a close. So I dive off 500ft and join the downwind leg, making a rejoin call on the radio.
Now comes the moment that’s been a slight worry ever since we took off: when I have to land the beast. Dave recommends an approach of 80kt, coming back to 70kt over the hedge. “But be careful ? she stalls at 60kt,” he says, “and she can drop on you below seventy”. As with most aircraft, I feel safer making my first approach straight, rather than sideslipped, but to get the speed back to 80kt, the nose has to be so high that not just the runway, but the entire airfield disappears. With a hedge and a road to cross, and not wanting to mush in, I end up coming in a touch high and a touch fast. However, Little Gransden has a long runway and it feels as though we’ll get in okay off this approach. I flare and now have nothing but the edges of the runway to guide me. No problem, although we do seem to be going awfully fast and using up a lot of runway. Nervously, I touch down while the S-2A still has excess energy. We bounce ? boing from the tight bungee suspension, notoriously unforgiving ? and the nose comes up, but the change in attitude and the bounce are modest, so I hold steady and after a couple more bounces with lesser boings, we are down to stay. The short-coupled undercarriage sends us bucketing along the grass. I’m pushing hard at the toe brakes to bring the violence to the earliest possible end. When we slow enough for me to see how much runway we’ve got left, it’s at least a third.
“Phew,” I say through the intercom. “That was a bit rough.”
“Just a normal Pitts Special landing,” says Dave. “Plenty of mine are like that.”
I know, from experience, that anyone watching would have seen an ordinary touchdown. One feature of Pitts Specials is the tight bungee loops that brace the undercarriage; they transmit every bounce and lump in the grass directly to the occupants and it always feels worse than in it looks. With long intervals between my flights in Pitts Specials nowadays, my first landing is usually a poor one, but my second much better. Rather optimistically I say as much to Dave as we backtrack for a final circuit.
The takeoff run this time feels like about 250 metres and the initial climb seems to be about 1,500fpm. I make a tight circuit, then position a little further out and higher for my final approach. This time I come down in a sideslip and everything is much easier, with the runway and threshold in view the whole way down. My speed and altitude control is more exact and I cross the hedge with the ASI just below 80kt and unwinding. I un-cross the controls a moment later and we are whistling down the runway a few feet up for a second time, only now it’s at the start of the runway instead of one-third in, and we’re a good five knots slower. With no feeling of haste, I keep the S-2A flying just above the grass until its energy is thoroughly dissipated and only then allow the wheels to touch. We contact smoothly, the aeroplane runs straight and some gentle braking brings us to a full stop within less than half the runway. What a satisfying end to the flight!
I turn the aeroplane and taxi in, feeling, now that it’s all safely over, tired but happy. Carefully I manoeuvre past parked aircraft, the fuel pumps and the corner of a hangar into the space that seemed so narrow when we left it earlier and with toes on the left brake and a quick burst of throttle perform the Pitts party trick of pirouetting 180 degrees on the spot and stopping. I run the engine a little longer to cool it and pull the mixture control and the Lycoming winds down to silence.
Only 259 S-2As were factory-built, with some additional S-2Es, the homebuilt version, completed from factory-constructed kits. I counted 28 S-2s and S-2Es on the G-register. This doesn’t include Dave’s, of course, since it’s on the N-register. I should imagine that there are others.
I can see why James Gilbert would have made a visit to Curtis the first thing on his agenda all those years ago: the Pitts Special in all its variants is one hell of an aircraft.