Aviation has its fair share of characters, both human and mechanical. It is the mechanical ones, the aeroplanes, that are particularly fascinating, because of the surprisingly personal characteristics possessed by some individual aircraft within types. Usually the outstanding characters can be expected to come from the ranks of the charismatic fighter and bomber types, but one transport model in particular that seems to have been promoted up from the lower ranks of interesting aircraft, is the de Havilland Dragon Rapide, first flown sixty years ago. In a promotional brochure, the makers blandly describe their new 1934 Rapides as
" Light twin engine biplanes of wood and fabric construction, equipped with a cabin arranged for eight passengers and a pilot. They are powered with two Gipsy Queen III engines driving fixed-pitch propellers."
That uninspiring description does not presage the strength of interest shown by so many people in what might be presumed a relatively boring old biplane. It does seem however, that there is great interest in this wood and fabric transport, as exemplified by the surprising number of positive comments made about a recently restored Rapide. Over a period of a few weeks, seven people, at unrelated events, when hearing about the Rapide in question, came alive with excitement in relating their own stories of how they remembered the type with great affection . Most had taken their first flight in a Rapide at the early London Airport, or at Land’s End; some had remembered the pioneering communications work done by the aircraft post-war; some had maintained it, and others had flown it. But not one of the memories recalled the noisy, cramped cabin, the slow and turbulent flights, the poor headroom or the rather alarming lack of performance. Without exception, all who remembered the aircraft expressed a great affection for the old girl, mentioning that it was quaint, old-fashioned, had small but surprisingly comfortable leather-covered seats, and there was a unique intimacy, with the pilot sitting up front in his cockpit, within shouting distance of his passengers. Each was fascinated by its feeling of "character".
Is this unusual stirring of interest amongst thjose who flew in Rapides reflected in the attitudes of those who operated it? A view from the aircraft’s front seat may provide a feeling for the pilot’s relationship with this bland old bird.
The appearance of this machine is like no other, if you discount its larger, chubbier four-engined predecessor, the DH 86 Express. The uniquely nineteen thirties lines and curves, as she stands ready for flight, reveal a paradoxical design. The smoothly flowing shapes of fuselage, engine cowlings moulded into undercarriage "trousers", and elegantly tapered wings are examples of aerodynamic efficiency, designed to be drag reducing, so permitting higher speeds. Yet this two-and-a-half-ton aircraft sprouts two pairs of forty-eight foot wings and a surprising number of struts, double bracing wires, exposed fittings and other excrescences, all sitting out in the airflow, and each adding to the already high, inefficient drag. They all add to the charm of the design, but surely the extra aerodynamic drag must outweigh the practicality of the well-streamlined shapes? Would the same engines and load capacity, combined with a neat, cantilever monoplane wing and total adherence to streamlining have produced better range, higher speed and better single-engine performance? It would appear that, in the end, the practicalities of retaining existing manufacturing processes and materials, and the operating experience already gained with the Rapide’s siblings, the Dragon and the DH Express, made the need for better streamlining seem uneccessary in the early ‘thirties. The design performed well enough when tested, so further refinement work would merely have added to the purchase price in a very competitive market.
It was quite fortuitous that no further changes were made, as the whole appearance of the aircraft is delightfully de Havilland. Who else could have drawn that complex combination of flat glass panels and curved wooden structure which form the pilot’s pulpit, or around the engine cowls, which seem to melt into the undercarriage struts, and encompass the fuel and oil tanks in passing? No other designer could have produced the elegant lines flowing rearwards from the wide fuselage into the tall DH trade-mark fin and rudder in such a stylish way. But what about the view from inside?
Once the administrative and external preliminaries are tidied up, the pilot reaches up to open the small cabin entrance door on the port side. The first sensation is one of quality, aided by the luxurious aroma of the leather seats and the typical DH style gray and green furnishings, executed with subtle good taste. No modern plastic fittings and glue smells here. Stepping up to the door sill takes one over the port wing root, which is a weak point on parachuting Rapides. It seems that the minds of exiting parachutists have no concern for the delicacy of wooden wing root structures, as most Rapides used at some time for this somewhat hearty pastime have wing roots badly damaged by exuberant parachutists’ booties, both on embarkation and departure. Ducking into the doorway, the eight dove gray seats can be confirmed for security, and the cabin emergency equipment checked for safe stowage. Then the steep climb up the sloping cabin between the snugly fitting passenger seats takes one to the forward bulkhead, the front face of which the pilot uses as a backrest. What could be called the Captain’s Briefing Notice is fixed on the cabin side of this bulkhead. On its ivory surface is printed, in an elegant ‘thirties script:
Passengers are Reminded to
return to their seats on Approaching
an Aerodrome and Landing
That sets a nice period style for the trip.
The immediate impression of the cockpit is of a cramped, angular workspace, with plenty of glazing above, to the sides and ahead. The single pilot’s seat is a minimal wooden box, now fitted with a leather back and cushion to match those offered to the paying customers. As a token gesture towards safety, a full safety harness is now fitted, but that’s it. No adjustment for height, rake or reach. No armrests. Just a (nicely covered) box with a vestigial backrest. The DH twin transport which followed thirty years after this one has progressed several hundred percent in terms of pilot comfort, but that’s what gives this DH model part of its charm. Surveying the shiny brass and wood fittings and the airfield congregation below, gives the air of being seated at an old-fashioned pulpit, with its instrument panel making a passable lectern.
Around the pilot are spread the means of operating the machine, fitted with little apparent thought for their concurrent use on the ground or in the air, being placed more for the convenience of the specialist fitting that system into the airframe. Of course, they can all be reached or seen when required, but not in the most convenient way, as with a modern ergonomic cockpit. While most controls are roughly where you might expect them to be, it is only with practice that they come easily to hand, and some, such as the fuel cocks, brake and flap levers, are awkward to operate.
Starting is usually simple, unless the aircraft has not been run for some weeks. With the pre-start checks complete, the starboard engine is primed up to eight times with the little Ki-gass pump on the starboard cockpit wall. All Rapides have electric starters, so after switching on the two magnetos, the starter button is pressed, until the engine fires. If the weather is cold, simultaneous priming and cranking may be necessary, which means right hand to cope with the uncomfortable pumping action, and left hand on the starter button, with the knees gripping the central control column to keep the elevators up. The throttles can be left alone. However, most starts are quite straightforward, and then its time to start the "three handed taxying game".
The aircraft has a castering tailwheel, a large moment arm between tail and main wheels, and a large keel surface aft of the centre of gravity. It therefore tends to "weathercock" its nose into the wind, so brakes have to be used on the ground to counter the effect, particularly in a strong wind. Brakes have to be used to steer accurately, but the brakes tend to slow the aircraft down, requiring the use of higher and often asymmetric power. Asymmetric power alone can be used for coarse turning control, but this requires considerable anticipation if over-turning is to be avoided. However, a potential effect of increasing power in certain wind conditions is to allow the tail to rise, and therefore the nose to lower towards the ground. This combination is the dread of all Rapide pilots who have seen photographs of colleagues who broke their noses through letting their tails rise while applying brakes. The Rapide’s nose cone crushes as quickly and easily as its pilot’s pride in a "nose over". All this is leading to the question of how to control these manoeuvres on the ground. In light winds the two throttles can be moved independently with the left hand, and the control column easily kept in its rear position with the right hand. Turning can then be controlled by small amounts of differential brake applied via the rudder pedals. Simple enough.
However, taxying in a cross wind requires use of the hand brake, which is on the left cockpit floor abeam the pilot’s knee, and only reached by the left hand, and which must be constantly adjusted to stop the wheels from locking. More modern aircraft make use of control column brake levers or toe brakes, but not this dear old girl. When the wind is strong, the left hand is needed for constant attention to the throttles to move forward, as well as continuous use of the brake lever to control the direction and stopping. If one happens to have only one left hand, one is then forced to use the three-handed method scoffed at by non-Rapide pilots. It works like this. The control which needs the most careful and constant adjustment is the brake lever, low down on the left side, so the left hand is used for the constant brake work. The pilot then hunches forward while crooking his right arm round the front of the control column, forcing it rearwards, and stretching up to move the two throttle levers on the left side wall with his right hand. This may explain why all real Rapide pilots have hunch-backs and gorilla-like right arms. This is one of the most tricky of all aircraft to taxi, but the challenge makes the practice more interesting, and it adds to the fun.
The rest of the operation is easy, unless you happen to have an engine failure, when the marginal performance again requires delicate hands and feet to maitain very accurate speed and balance.
With the simple Pre Take Off checks completed, the aircraft is ready for take off. Captain de Havilland’s notes tell us that she should use up only 535 yards to reach a height of fifty feet on a maximum weight take off, in nil wind conditions, but that target sometimes seems improbable when viewed from the start of a short field. In fact the performance is lively, as the ground roll is pleasantly short with any sort of headwind. As to be expected with a ‘thirties design, this aircraft feels most comfortable on grass runways, being more skittish on tarmac. The main concern on hard runways is of course the wind direction, which is never right down the middle, so forcing a cross-wind technique. With anticipation of weather-cocking into wind, a combination of slower than usual opening of the throttles, coupled with careful use of rudders and positive rotation off the ground, the problems inherent in tarmac take offs will usually be solved. In this case we are taking off into wind on a gently undulating grass airfield. After initial application of staggered throttle to counter any torque-induced swing, the Queens settle into a deep, steady bellow, and a check on the gauges confirms their willingness to work. Only small amounts of balancing rudder are needed as the speed builds, to deter any tendency to swing off course. Keeping the column back, then gently towards neutral as speed increases and the old girl undulates across the grass, she stretches upwards on her undercarriage a couple of times, until she flies herself off the ground at around 50 knots, eager to be airborne. The engines are checked again, while awaiting the seconds taken to reach the critical single engine speed of 65 knots. With safety speed achieved, the pilot can cope with an engine failure, and can afford to increase up to his climb speed of 85 knots, which only takes a few more seconds. Controls are nicely effective in the climb, the heavier ailerons beginning to require more muscle power but the rudders and elevator feeling light and positive. The Queens need a delicate touch at this point to synchronise engine speeds and so prevent the typical, irritating asynchronous beat which occurs with all propeller twins.
Now that she is safely in her element, the machine feels more comfortable, with the seating and the controls better adapted to the airborne phase. Despite the greater feeling of comfort, anything over two hours airborne, even with high quality leather seats, is something of a discomfort to the pilot, sitting on his upholstered box. The panoramic view out over the pulpit is something enjoyed by the pilots of few aircraft, old or new, because of the sloping glazed panels ahead, to the sides and above. Navigation at close ranges to the aircraft is therefore easy, until the next major Rapide foible is encountered. Because of the acute angle of the two centre windscreen panels relative to the airflow, flying in anything heavier than light rain decreases forward visibility to about two feet. Sideslipping and changes of speed have no affect whatever, so the only alternative to pure instrument flight is to open one of the sliding side windows, thereby gaining a moderate increase in visibility and an unbelievable volume of water in the cockpit. That is also the reason why all-weather Rapide pilots wear long raincoats and wellingtons in flight.
This is one biplane which needs only moderate balancing rudder in normal turns, unlike most aircraft of its era. Trimming is accurate and sensitive, using the large trim wheel down by the left knee, which all helps to make this a stable platform for cruising flights. There is little else to manage in the cruise, except for watching the fuel gauges and adjustment of the fuel mixtures when flying above 5.000 feet. With no such equipment as engine cooling cowls, mixture controls or even engine temperature gauges to worry about, the cruise is usually spent, in inverse proportion, admiring the countryside, navigating, watching the fuel and oil pressure gauges and battling the engines’ pervasive de-synchronised mode. This delicate operation, adjusting the throttles and RPM levers if fitted, to keep the engines exactly in tune, is an almost continuous task.
When heading back to base for the more challenging phase, the landing, a quick check of altimeter, engine gauges, fuel levels, radio, and the navigation is completed, and the throttles gently retarded to allow the Queens to cool, and the nose lowered for the descent. Speed increases, felt and heard by the increased pitch of the flying wires’ whistle. The myriad air gaps and holes around the cockpit windows and nose join the chorus, not quite in harmony, but at least in unison. This is one of few "seat of the pants" transports, which could almost be flown by sound and feel alone. Descending somewhere just above middle "C", which equates to about 120 knots, is comfortable as well as practical, unless there are passengers on board, when a gentler alto descent is more appropriate. Visibility in good weather is excellent, so a nice tight circuit can be happily flown, using distances slightly greater than for a Tiger Moth, to cope with the extra speed.
There is a strong wind at the home strip on return, so all the way round the circuit a close watch is needed on the airfield windsock’s wanderings, to assess the mean wind speed and direction. In these conditions, very much the sort of weather in which the pioneering Rapide pilots regularly flew their incredibly regular services to the Highlands and Islands, the old Rapide needs different skills and thought processes from those applied to modern twins.
Despite the pilot’s attempts to will the wind into a more convenient westerly direction, it persists in blowing from the north west, which only allows a short landing run and the choice of two difficult approaches to this short strip. The more northerly approach is slightly closer to the general wind direction, but that approach would need a hop over a twenty five foot telephone line running parallel to the stone boundary wall, and then straight towards the farm at the other end. The other possibility is to approach on the slightly longer westerly run, about forty degrees out of wind, so avoiding the high trees on the boundary, then turn sharply into wind at about twenty feet, within the airfield boundary, for a slightly longer ground roll. The telephone cable route looks tricky in the strong, gusty wind, so the out of wind approach followed by the last minute turn into wind seems the most practical.
With the standard fixed pitch propellers, a good circuit RPM for the Queens is 1,900, which produces around 85 knots at the end of the downwind leg. Aircraft modified with constant speed propellers need to have their propeller levers adjusted to give 1,900 RPM at this point, then the throttles set to match, at about minus three boost. The strong wind wisks the aircraft rapidly downwind, as the rudimentary downwind check of setting mixtures, fuel contents and brake lever are completed. The touch-down point of the landing strip appears again behind the port lower wing, indicating time to turn onto final approach. Throttling back to a gentle 1,200 RPM gives around 85 knots in a descending turn, the cross-wind skidding the aircraft sideways at a surprising rate, onto final heading. A reminder is needed here not to go below the single engine safety speed of 65 knots until committed to land, then use is once again made of the long right arm, to reach down for the flap lever’s catch, which is now inconveniently at the top of the lever, way down on the forward cockpit floor. Flap selection with tight shoulder harness is impossible in this machine, unless you are an Italian racing driver or an Orang Utang. (Rapid oscillations on final approach in Rapides can often be attributed to short-armed pilots attempting to configure their aircraft for the landing.)
Turn rate, angle of approach and speed are balanced until the machine is lined up nicely on the selected final approach, allowing for the forty degree crosswind, at 75 knots and 400 feet. The extra five knots should cover the higher than usual wind and the final turn into wind. Approaching 400 feet, everything looks as expected inside and on the windsock, so committal to landing can be made, followed by a speed decrease towards 65 knots at the threshold. The aircraft is very sensitive to gusts and has to be handled carefully near the ground, particularly at slow speeds, as it will readily drop a wing at the stall, especially if asymmetric rudder or power are applied. Normal approaches in calmer conditions are much more friendly, as the aircraft is then smoothly responsive to the controls all the way down to touchdown, allowing accurate speed control and judgement of touch down point. Rough weather is a different matter.
The wind is obviously causing some turbulence near the ground, as at about 300 feet, the right wing suddenly drops about thirty degrees, prompting a rapid application of full opposite aileron and some rudder to pick up the starboard wing. She struggles back to an even keel, then the turbulence decreases as the ground below smooths out. The direction of approach is working out well, and speed is averaging about right as the aircraft crabs into wind, forty degrees or so off the final track. Extreme caution is now needed to stop the wind drifting the aircraft into the high boundary trees on the left, as the machine creeps in over the wall, preparing to turn right into wind. A last look at the speed, 65 over the wall, then right aileron and rudder to skid back into the strong wind’s throat. At about 15 feet, wings level, the column can start to come back to decrease the descent rate, throttles brought backwards and then she is gently on the grass, level and running nicely, straight into the breeze. There is no need for brakes with this wind, so the tail can come gently down as the speed dies towards a walking pace. Somewhat surprisingly she has stopped in less than half of the available strip, despite the final correcting turn inside the boundary.
With the excitement of the airborne element complete, the equally challenging taxying game can be tackled. But first, the long right-arm stretch to lock the flap lever in its retracted position, and the thinking can start on how to cope with cross-wind taxying in this wind. Some speed is kept on for the first part of the turn, and with asymmetric throttle and sparing use of the brakes, port aileron up as the turn crosswind is started, and the turn is started. The manoeuvre works safely, and the aircraft is soon running downwind, back towards the hangars and safety. After Landing checks are finished on the move, as they only consist of checking the flaps up and switching not-needed radios off. On reaching the hangar, the old girl is turned into wind, the trusty Queens run up to 1,000 RPM to cool for a minute. Then its time to switch off the radios, lights and fuel, then the four engine magnetos, and let the props jerk to a halt. Now the comforting bellow of the Queens has died, the quiet whirring-down of the the air-driven gyros is interrupted by the clunk of the brake lever as it is released. This spritely sixty-year-old is once again left to her own silence.
For a pilot of a later generation, it is a privilege to accept, in part, the same flying challenges presented to the pioneers of British aviation sixty years ago, and to be allowed a practical insight into the demands and the fun inherent in flying those machines.
COLIN DODDS