Johan Walden - TIES, BUTTONS AND BARS

The Grob 109B - one of the two planes that Jim regrets selling. Photo by Ian Howat on AirHistory.net.

bloody undercarriage. You see, the air around us hasn’t changed much since the 1930s – so the flying bit of the aeroplane is fine. But the advent of runways – instead of nice open grass fields – has caused all sorts of problems for the bits of the aeroplane that interact with the ground. The wheels, the tyres, the brakes, the suspension – just kidding there isn’t any. The silly marie biscuit tyres were meant to absorb all the bumps.

When the Junkers was designed you taxied a short distance in a straight line to your takeoff point and then turned into wind. Same when you had landed – a straight line taxy to your parking spot.

With the advent of runways things became complicated. You have to taxy a hell of a long way on a hard unforgiving surface, and you have to keep turning on to different taxiways. Nothing about the structure below the wings was designed to cope with such things.

There are no toe brakes - simply massive rudder pedals with leather straps over your feet. The straps serve two purposes, they help you keep your feet on the rudders in turbulence, and they enable you to shove with one foot and heave with the other. Almost everything on the aircraft requires massive physical strength. There’s no power steering or fly by wire – you physically push and pull things that are connected via railway fixings to other things.

My mate “Squintin” – Mike St Quintin – says, “The JU bounced along during taxi, it had no oleos, springs etc. The bouncing came from the tires acting like a spring with no shock absorber. This, I believe, is what caused a loosely fitting tire to come off the rim.” Except it didn’t just happen once – it was a reasonably common event.

Mike goes on to say, “I never had trouble with the air brakes other than they were unpredictable in how effectively they would work. They could be a bit grabby and equal pressure applied to both brakes was never guaranteed to cause equal braking. Actually it very seldom did.

The brakes are powered by a compressed-air bottle under the co-pilot's feet. This air is fed through a mass of pipes, valves and pressuregauges, to… guess where… the throttle levers. Throttle back the left motor and you have left brake. The right throttle will do the same for that brake, while the centre throttle works both binders.

With long distance taxying two major problems arise, the brakes quickly overheat and stop working, but worse still, every time you throttle back there’s a hissing of compressed air, like the old steam trains, and the pressure gauge reminds you that you only have a limited number of shots till the bottle is empty and that was your braking allowance for the day.

Another interesting system supplies oil (but not fuel) to a failed engine. If one packs up there is no way to feather the prop - it just keeps windmilling, and therefore needs to be fed with oil, but not fuel. All very complicated.

Start-up is typical for round engines - plenty of wobbling wobble-pumps, winding up and meshing of inertia-starters, and billowing clouds of blue smoke. Everyone enjoys that.

Take-off is a stately affair. The tail comes up as soon as you have full power. The engines bellow and trail smoke while she lumbers forward. After about 200m she drifts gently into the air and climbs with more dignity than spirit. Perhaps like an elderly butler carrying a silver tray with a whisky and soda up the mansion’s sweeping staircase. This lack of urge is to be expected as our three Pratt & Whitney Wasps – borrowed from Harvards – push out a total of 1800HP. This is 600HP shy of the 2400HP developed by the original BMW motors.

Once settled in the air you realize you are surrounded by glass. Strangely that doesn’t make for good visibility but it does mean you can keep a close eye on those thundering oil splattering engines. At least for a while until the centre engine chunters out enough smoke to cover the windows with an ever-thickening film of oil.

These engines make their presence known. The bellow of open exhausts only feet from your eardrums, and a rumbling vibration combine to let you know that you are being dragged through the atmosphere by radials. Ignore their temps The whole lot thunders along at a stately 90 knots. Sir Isaac Newton – had he been there – would have applauded the manner in which the Junkers obeys his law about things carrying on doing what they were doing, until acted upon by an external force. With the JU-53 the external force is supplied by the pilot. It takes massive physical muscle to make this aircraft do anything. The elevator is heavy and slow, the ailerons are heavier and produce more adverse yaw than roll, while the rudder requires such brawn that even the master-race had difficulty populating these cockpits with adequately strong-legged pilots.

Unfortunately we had a dozen pax, so steep turns and stalls were not on the menu and I had to content myself with doing pansy turns and fighting the turbulence caused by a mean burg-wind which had just sprung up. All too soon it was time to return to base. The engineer opened a hatch in the roof, climbed on a wooden box, head-and-shoulders in the slipstream, and wiped the oil from the windscreens so we could see the runway.

With a strong, gusty, 90 degree crosswind, the landing was interesting. Scully used most of the two kilometres of runway to battle the blasts and avoid taxying too far, while gently feeling for the ground with one wheel. I kept thinking of what Mike had said about tyres coming off the rims. We taxied in with huge bursts of power and much puffing of brake-pressure as he wrestled the squalls of hot air.

As we were shutting down Derek Dumbleton, a local crop-spraying pilot, stuck his head into the cockpit. “I don't know how you lot keep three of these engines going - I have enough trouble with one of the bastards."

So there you go Zingi, my long deceased friend, how much time do you have on a JU52?j