'Change to Ben Gurion Tower, frequency 118.3.'

'Whiskey Zulu, 118.3.'

I switched both sets over. 'Queen Ak Whiskey Zulu listening out.'

I stopped at the holding point and did a careful run-up on both engines, checking for mag drops. Nothing much.

'Whiskey Zulu, ready for takeoff.'

'Whiskey Zulu, Met advises line of electrical storms approximately fifteen kilometres west, inbound flights report severe turbulence.' The clipped voice was as carefully unemotional as a laundry list.

With the midday temperatures and coastal effect, the front was winding up tight. Well, if it was rough upstairs it would be bad below stairs; that's what I'd wanted, wasn't it?

'Thank you, Tower. But haven't you heard of heroes?'

'Whiskey Zulu cleared for takeoff on runway 30, wind now reported 270, 25 knots gusting to 40. Climb initially to 3,000 feet, maintaining runway heading until outer marker, then resume normal navigation.'

'Whiskey Zulu, rolling.'

But not for long. The airspeed needle flickered almost before I'd got the throttles open. I stayed on the ground well past 90 knots – a sudden drop in the wind could slam me back with a crunched under-carriage – and when I lifted off we went up like a nervous lift. Half the wet-shiny black runway still stretched ahead when I was wheels up and throttled back into the climb.

The Tower came back: 'Whiskey Zulu, airborne at oh-seven. Change to Ben Gurion Approach, 120.5. Shalom."

'120.5. Not up here.'

As I reached to switch channels again, something moved on the main panel. When, I looked back, the ILS dial was dead. With its dying volts, it had managed to put up both OFF flags, and I hope I go as thoughtfully.

The first cloud came at 2,500 feet. Just thin wet stratus without any extra turbulence – in fact things were smoothing out as I got clear of the rippling effect of the ground. After another half minute the grey turned to a gentle golden glow, the rain drained off the windscreen – and I was in a new world.

A hard bright sun blazed over my left shoulder and glared back off the fluffy white cloud below – the top side of that dank stratus I'd just cleared. The total was as bright as a ski-slope; I blinked and squinted before I got my sunglasses on. But ahead…

It reached higher than I could see with the cockpit roof in the way, and far out of sight to either side. A bulging, boiling wall of cloud, blinding white in the sun but so dense it threw black shadows on itself below the bulges. As I watched, one of the black patches flashed green-blue with internal light.

For a pilot, this is the wall ofthe eternal city. Its ramparts higher than Everest and older than Jerusalem, yet so transient that it can build itself and fade inside a day. And you can spend that day in the bar – but there'll come another. A day when there's just you and the wall and a reason to get through.

But not me, not today. All I had to do was get blood on my sword. I'd still have settled for a nice calm sea fog, if Israel went in for that sort of thing.

I had a couple of minutes left; the aeroplane hung steady as a picture on a wall as I switched off the loudspeaker and plugged in the earphones, ready for things to get noisy, and turned up the radar brightness. It was still playing up, not reaching beyond ten miles, but that showed enough: a ragged but solid bar of shimmering light, from about five miles onwards. Rain. Rain thick enough to throw a reflection like a hillside. I turned the contour switch.

The screen blinked and the line hollowed out to an irregular row of dark holes, almost linked. The thunderstorm cells, churning private cauldrons of up-and-down draughts. The strong points of the wall. I weaved the nose to give it a better view south and north, but no obvious weak points.

Did I really want one? Half of me did; even twenty years of built-up flying instinct wanted the safest way. Problem: how to get into trouble safely.

I could try one thing. 'Ben Gurion Approach, Whiskey Zulu. Request clearance to descend on track and try to get below this stuff.'

'Whiskey Zulu, stand by.' I tightened my straps, pushed up the carburettor heat levers.

'Whiskey Zulu – negative on descent. Continue climb to flight level 80.' What I'd hoped for – what half of me had hoped for. The Israelis don't like aeroplanes down low off their coast; they want them up where radar gets a proper view.

The light glowed on the marker receiver: I was just about on the coast.

'Ben Gurion Approach, Whiskey Zulu on outer marker. Turning to intercept Blue 17.'

I hauled around to the right, steering 340 in the hope that it would give me a track of due north. By rights, the VOR should be giving an exact track, but I'd bypassed those rights.

Approach came back at me: 'Whiskey Zulu, change to Tel Aviv Control, frequency 124.3.'

'Whiskey Zulu, roger.' I made the change. Now, briefly, I was flying parallel to the bubbling white wall, but it was moving on me as I headed north and it came east.

Tel Aviv Control, Queen Air Whiskey Zulu.'

'Whiskey Zulu, go ahead.'

'Whiskey Zulu passing 6,000 feet…' I reset one altimeter to the standard atmosphere figure of 1013 millibars; my indicated altitude wound up by almost a thousand feet…

'… airborne at 12.07, estimating Blue 17 at 12.28…' I spelled out the whole meaningless formula. A glance at the ADF needles, which should have been pointing somewhere behind. Instead, they overlapped, both quivering like bird dogs and sniffing east, at electric power sources a thousand times stronger than man-made beacons.

'Whiskey Zulu, call at flight level 80.'

I wasn't quite going to get there before I had to turn into the wall. Close up, the scale of the thing is always unbelievable. The tiny crafted details you see at twenty miles become vast crude brush-strokes – live ones. Lumps the size of cathedrals bubbled and rolled like breaking waves. It's the hungry surge of a thunderhead that the paintings can never get.

7,000 and I must be about on the line of Blue 17. I turned left, switched up the cockpit lighting full – and just remembered to take off my sunglasses. I had my head down and was settled into the rhythm of instrument flying before the cockpit went dark around me.

110 knots, nose above horizon, going through 7,400 feet, climbing about 900 feet a minute, heading 325, start again: 108 knots, push the nose down a fraction, just over 7,400, climb rate dropping, heading steady, start again… a constant sweep of the eyes over the panel, tiny corrections passed to the hands, almost bypassing the brain. Never concentrate on one thing. You have five items to watch; stare at one sheep and the other four are scattered to hell. Speed, horizon, height, climb, heading. Again…

The wings rocked stiffly and the neat pattern warped; pat it back into place. A faint rattle of rain nibbling through the drone of the engines, but skip the wipers: I don't want to see out anyway.

The windscreen blazed with light, half-dazzling me despite the cockpit lighting and my deliberately bowed head. When I caught up with my reading again, the nose was down, airspeed going up, climb almost nil, heading five degrees off. Less smoothly, I dragged the pattern together.

It began, now. The whole aeroplane lifted and stayed lifting. The climb needle paused as if it was surprised, then shot past 2,000 feet/min. I let us go, just tried to keep the wings level and nose not too high. You don't fight thunderstorms, you just roll with the punch.

The sky fell out from under, jerking me up against the harness; the needle whipped down to a 2,000 feet/min descent. The heading wavered between 320 and 330 degrees.