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After an incredible life of 89 years since first flight, the South African Air Force announced the retirement of its Douglas DC-3/C-47 in May 2024.

The “Dak’ is a genuine legend and to commemorate its retirement, we put you in the pilot’s seat to find out what it is like to fly a true legend. Derek Hopkins shares the  joys and hazards of flying what many consider to be the first true commercial airliner.

Amazingly after 90 years there are still hundreds of Daks operating around the world, some with more than 100,000 hours on the airframe.

When it was designed in the 1930s, fuel was cheap and it was easier to over-design rather than maximise weight saving. So it was built strong.

But the Dak has another rare feature, which is a key factor behind the design’s longevity. It has no main wing spar, just a complete mid-fuselage section manufactured as one piece, including inner wing and engine nacelles. The outer wing skins are bolted  onto the mid-section, using 328 bolts and carefully torqued Nylock nuts on each wing.

Our subject aircraft is Menno Parsons’ ZS-CRV,  a C-47, the military transport version of the DC-3. It is powered by two Pratt & Whitney R-1830 radials, each developing 1,200 hp.

Development

DC stands for Douglas Commercial. The prototype DST (Douglas Sleeper Transport) first flew on December 17, 1935 (the 32nd anniversary of the Wright Brothers’ flight at Kitty Hawk) with Douglas chief test pilot Carl Cover.

Compared to contemporary airliners, the DC-3 was fast, had good range, was more reliable, and carried passengers in greater comfort. Before the WW2 it pioneered many air travel routes. It was able to cross the continental United States from New York to Los Angeles in 18 hours, with only three stops.

It was one of the first airliners that could profitably carry only passengers without relying on mail subsidies. In 1939, at the peak of its dominance in the airliner market, around ninety percent of airline flights on the planet were by a DC-3 or some variant.

Following the war, the airliner market was flooded with surplus transport aircraft, and the DC-3 was no longer competitive because it was smaller and slower than aircraft built during the war. It was made obsolete on main routes by more advanced types such as the Douglas DC-4 and Convair 240, but the design proved adaptable and was still useful on less commercially demanding routes.

Surprisingly, the true DC-3 is a rare aircraft. DC-3 production ended in 1943 with just 607 aircraft. However military versions, including the C-47 Skytrain (the Dakota in British RAF service), and Soviet and Japanese-built versions, brought total production to over 16,000. Many continued to be used in a variety of roles; as of 2023 it is estimated about 150 are still flying.

Early-production civilian aircraft used either the 9-cylinder Wright R-1820 Cyclone 9 or the 14-cylinder Pratt & Whitney R-1830 Twin Wasp. The R-1820 was chosen for most military versions and was also used by most DC-3s converted from military service.

Five DC-3S Super DC-3s with Pratt & Whitney R-2000 Twin Wasps were built in the late 1940s, three of which entered airline service.

On the ground

The Dak has great ramp presence. From the ground it is huge for a tailwheel aircraft, and the cockpit is far above ground. An immediately noticeable feature is the escape hatch on the left-hand fuselage, just behind the cockpit. If, during an evacuation, the still-turning left propeller (the tips just miss the hatch) didn’t kill you, the 7-metre drop will.

The Dak’s stance on the ground is 12 degrees nose-up so, after entry via the rear door, the pilot is faced with a climb to the cockpit, more like mountain hiking than piloting.  But once you get there, and have got your breath back, the true character of the cockpit becomes evident.

It is a classic ergonomic disaster with key controls seemingly added as an afterthought. Notable are the no-less than twelve levers and knobs on the centre pedestal. The power levers are not conventional power, pitch, mixture from left to right. The throttles are the tall levers in the middle, thus giving pitch, power, mixture – like early Barons.

The centrepiece of the panel is the classic ‘whisky compass’ which is suspended on bungy cords above the glareshield. Below that is the exposed pneumatic plumbing for the windscreen wipers.

Given its vintage, it is unpressurised, so the cockpit windows slide open. They look as though they come from a Series 1 Land-Rover. In a rainstorm the windows and the escape hatch above the pilots can be guaranteed to leak like broken drainpipes. For experienced pilots, large rolls of super absorbent paper towels are standard equipment.

The pilot seat looks like it’s from a 1930s Massey-Ferguson tractor and, if the internal springs are old, height adjustment can be a depressing affair. Once you are in the left seat, you can see nothing but sky out the windscreen. The field of view to the side is okay, but visibility forward while on the ground, with such a nose-up attitude, is poor and through the opposite right-hand front windscreen bordered on non-existent.

Starting the Pratt  & Whitney R-1830s is an art. For the uninitiated, it seems as though you need to be a concert pianist to pull off the complex sequence of, prime, boost, propeller turns, magnetos, mixture and revs.

The best part of a radial is the burping, belching, barking, start as the huge cylinders reluctantly come to life. Once the engines are firing on all cylinders you need to pressurise the hydraulics using the four levers (including the gear and flap operating handles) on the hydraulic panel, which somewhat typically yet unhelpfully, is behind the co-pilot’s seat. Hydraulic pressures are however easy to see, because the gauges are big enough to have been borrowed from a locomotive.

With both engines burning and turning, you need to check temps and pressures are in the green. However this is really the co-pilot’s job as the engine gauges are behind the ship’s binnacle sized power quadrant.

Taxying the big taildragger with its castoring tailwheel is another acquired skill. With the rudder lock removed and no main control lock, holding the yoke and pedals in gusts requires strength. There are not many lady Dak pilots. Steering is best with differential braking using the toe brakes. But the trick is to use not just differential braking abut also differential engine power. With power and a dab of brake, tight turns around the stationary inner main wheel are easy – but not great for the tyre life if done on a hard surface.

Flying the DC-3

Once lined up for takeoff, the Dak becomes less of a handful. Power is applied by the pilot flying and completed by the co-pilot to give 48 inches boost at 2,700 rpm. Acceleration, even at light loads, is stately rather than brisk. Once you are moving, push the control column hard forward to get the tail up. The flight deck will be level by about 50 KIAS so you can finally see where you’re going.

Depending on weight, rotation is between 80 – 90 KIAS. Gear is selected Up by the co-pilot as soon as you are airborne because this is not an aircraft in which to have an engine failure after takeoff with the gear still down. The ladder frame and huge wheels create massive drag.

The climb rate of a fully loaded DC-3 benefits from the curvature of the Earth. But with no passengers or cargo, an medium all-up weight of 8,800kg and outside air temperature of 20ºC, you can see a climb rate of about 1,000ft/min at 110kt, using 35 in Hg and 2,350 rpm up to 8,000ft.

The Dak may have seven-metre long ailerons, but lateral control is still sloppy, especially if there is any slack in the control cables.  Notably too, the control forces are out of the is ideal standard proportions. The ailerons have higher control forces than the elevator (by about 3:1) and are slow to generate roll.

In the climb, the Dak has good response in pitch and yaw, with huge static stability in pitch. This means that high stick forces are needed to change the pitch angle from the trimmed speed. The opposite is then also true – once trimmed, the aircraft feels as if it can be flown hands-free all day. There is little Dutch roll, and just a small amount of adverse yaw with aileron input.  

Pulling the power back at 8,000ft, the clean stall is innocuous. At 50-55 KIAS there is a distinct airframe buffet and vibration through the yoke, followed by a positive pitch down without a tendency to drop a wing. The stall in approach configuration on for example, the base to final turn, with Flaps 1, 15 inches of boost, 20 degrees left bank and about 10 degrees pitch attitude is trickier. The pre-stall buffet is masked by the propeller slipstream and, if the stick is held back, the aircraft drops its left wing to about 70 degrees with 30-40 degrees nose down pitch. Recovery takes more around 1000 ft.

A standard circuit starts with the gear down and Flaps 1 on Downwind. In keeping with its generally idiosyncratic nature, the flap indicator is a screw head in a vertical slot that moves up to indicate flap going down. Flaps 2 can be selected on Base. Turn final with 18 inches boost at 95 KIAS.

Flaps 3 and 4 are then selected in stages to slow the aircraft to cross the fence at 75 KIAS and let it settle into a two-point landing attitude. Check forward to plant the mains and the tail can be held up surprisingly long. This is not a plane to hold off into a full stall for a 3-pointer.

As the tail drops, the rudder loses effectiveness behind the wing with the engines at idle power so there is no direct steering. Using differential braking is inadvisable due to unpredictable braking action. With the tail down the view forward returns to ‘sky only’ mode but the tailwheel steering is then effective.

The Dak POH says it has a 20 kt demonstrated crosswind landing limit. Beyond 25 kt it will require exceptional pilot skill.

Conclusion

It is a privilege to fly such a classic aircraft. Like many veteran designs, the DC-3 has moderate performance and many in idiosyncrasies and potential pilot traps that would never be tolerated in modern aircraft.

Have we come a long way in the nearly 90 years since Dak first flew? Yes, indeed we have. Pilots really were pilots back when the DC-3 ruled the world in the 1930s.