Birds, Clouds and Fire part 2

Those of you who have been following this blog carefully will know that I am currently flying a Cessna 206 aircraft for MAF in Kenya. Some of you will also know that the 206 has a single 6-cylinder piston engine.

In some countries (notably the good ole USofA) you can happily fly a single engine piston aircraft in the clouds for the purposes of commercial aviation. However in others, such as most of Europe and many countries in Africa (including here in Kenya), you cannot.

The story is a little different for single-engined turbine aircraft such as the Cessna Caravan and Pilatus PC-12 which MAF operate in Kenya. Due to the improved safety and reliability of the turbine engines compared to their piston forebears (at least in theory if not always in practice!!), they are allowed to fly IFR (Instrument Flight Rules) here, and so can dance in as well as around the clouds.

As for me and my 206, we are limited to flying VFR (Visual Flight Rules), which means I must at all times remain clear of cloud, and generally in sight of the surface. It is possible to fly VFR 'on top' where you are above the clouds, but to do that you need a gap big enough to climb through, and at your destination you need another gap big enough to descend through. It is also a slightly uncomfortable place to be, since if you did have an engine failure, you are first heading for the clouds before you have any hope of seeing a suitable emergency landing site.

And so to last weeks' Dadaab shuttle. The weather over the weekend was unseasonably grey with low clouds and rain. Normally by this time in August the rains are gone and Nairobi is warm and dry, maybe with some haze. As I rode my motorbike down Mbagathi Way at 6.30 on Monday morning I could tell the flight wouldn't be leaving anytime soon. The sky was dark, with showers to the west and low cloud hanging around.

The trickiest part of the flight would be getting out of Nairobi and to the lower ground. 30 miles east and not only does the ground drop away but the clouds that form due to the rising terrain tend to dissipate so that usually you can find a gap or fly comfortably underneath.

But not today. I did my preflight checks and confirmed that my 3 passengers were checked-in. A quick look at the Nairobi weather data and more importantly a good look out of the window confirmed that we would have to wait for the weather to improve.

An hour later one of my MAF colleagues took off in a Caravan and headed out east before turning north around Mount Kenya. I called him on the HF radio and asked for a weather report. He reported back that it looked bleak and in the few gaps that he flew through, the weather seemed all the way to the ground.

Back in Nairobi though things were looking brighter. The cloudbase had lifted somewhat and to the south there was sunshine poking through. After waiting for the latest forecast and actual weather reports, and talking with another pilot, we judged that it may have improved enough to depart.

I taxied over to customs and the passengers and their bags were soon loaded. We took off and climbed to 700ft. The visibility was excellent below the cloud. Everything was crystal clear, if a little dark. I turned east and headed for the 'Northeast Access Lane' a corridor of airspace inside the Nairobi control zone that threads like a needle between the Jomo Kenyatta International airport to the south and Eastleigh Airforce base to the North.

The corridor is around 8 miles long, but very thin. The distance between the two airports is around 3 miles, so I always stick to the dead centre of the corridor. So far so good. On track, on height, on speed and clear of clouds.

To the southeast I could see blue sky and brightness. To the northeast, Mount Kenya somewhere lurking in the dark grey wall of cloud and mist. And ahead, well it was difficult to tell. The cloudbase was still above me (just) but the forward visibility was deteriorating. Light showers appeared to be approaching my flightpath from the south. But I could still see the ground and was clear of cloud. So we continue on.

During my country training with MAF I had flown this corridor several times with Jane, and in some cases in worse weather than this, so I was comfortable.

And then things started to change. Some drops on the windscreen alerted me to the fact that we were entering a rainshower. Sure enough the forward visibility decreased further, to maybe 4 miles. at the same time the cloudbase lowered, and so I descended slightly to remain below it. Up ahead I thought I could see some brighter areas, but closer in there were some areas of significant cloud and precipitation.

Looking back over my shoulder I could see that my path back to Nairobi Wilson was still clear. It's one thing cautiously approaching bad weather, but another to become surrounded by it and have nowhere to go. I couldn't deviate left or right from track due to the corridor, so I checked again that my rear was clear (!) and continued. The cloudbase was continuing to push me lower, and on checking my Altimeter I saw that I was now around 500ft from the ground. Less than comfortable, but I've flown lower safely during MAF training. Ahead in the distance I could see the lower ground and brighter weather, but between me and that lower ground the clouds stubbornly persisted.

And then a heavier shower appeared in the windscreen. A wall of cloud also appeared ahead, lower than my current altitude. A glance over my shoulder revealed a deteriorating visibility behind. It was time to go home. I executed a tight 180 degree turn, called Nairobi Radar and told them I was returning to Wilson Airport via the corridor.

Ten minutes later we were all safely on the ground again. I apologised to the passengers that we couldn't make it today. They were grateful and understood that safety is our main priority. Sadly not all air operators in Africa share that priority.

Bet you can't wait for part 3...