Birds, Clouds and Fire part 3

"I can smell something burning!" shouted the passenger behind me over the noise of the engine. We had just taken off from Marsabit and were about 200ft off the deck. A few seconds earlier I had smelled the same thing, and was already scanning the guages and looking around inside and outside the cockpit for any sign that something wasn't right. I briefly smiled an unconvincing half-smile over my shoulder and calmly told the passenger that I could smell it too, as I tried to channel my adrenaline surge into working out what was going on rather than panicking....

The day had started well, with a very clear and pleasant flight on my own from Wilson Airport to Sololo, a small town right on the Ethiopean border, a good 2.5 hrs from Nairobi. I had been able to climb to 10,000ft and had a great view of the Eastern slopes of Mount Kenya as I passed by. As usual the three peaks were in cloud.

After picking up three passengers and their bags from Sololo, we flew south to Marsabit for fuel, as I had not been able to carry round-trip fuel due to the payload. The passengers in question had been facilitating a training course for rural pastors, in this remote border region. They were in good spirits and were happy for a short comfort stop to stretch their legs in Marsabit while I took on fuel.

All preflight checks done and all systems normal as we taxied out, turned at the end of the runway and increased power for take-off. The wind in Marsabit is often stiff (20kts+) but usually mostly a headwind, so despite being close to gross weight, we lifted off in no time and were climbing quite nicely as the unwanted aroma started to fill the cabin. Obviously an aircraft fire of any sort is an emergency of the first order. The three main likely fires one can experience in a light aircraft are an engine fire, an electrical fire or a wing fire (where the fuel is stored).

Something didn't make sense though. Sticking my head upwards and to the left allowed me to get a good sniff of the air coming through the outside air vent (as shown in the picture on the right), and sure enough, the smell was stronger. So that indicated that the fire was outside, rather than in the cabin. And it was unmistakably that of a wood fire, which was also encouraging because apart from my head there is nothing wooden in the aircraft.

After a few seconds more, in the words of Inspector Clouseau, "the mystery was solve-ed" as a reasonably large fire came into view on the ground, with a smoke trail gently rising into our flight path.

The whole escapade had lasted maybe 10 seconds, although as with many incidents like this it felt much longer. I showed the passengers the cause of the smell, and everyone relaxed. Within 5 minutes they were all asleep.

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...

Birds, Clouds and Fire part 1

No really, I'm fine. But in the last two weeks I've had some new experiences which have added to my knowledge and experience of flying.

The first was during the Dadaab run. I had departed from Nairobi soon after 8 local time with some passengers and arrived at Dadaab at around 10. After using the facilities at the Airport (right), I was all set to return to Nairobi with a three other passengers.

African Flycatcher

Lined up on the runway with the engine at 1700RPM I checked the magnetos one at a time and then opened up the throttle and released the brakes. We accelerated well and I was just at Vr (rotate speed) when I spotted a small flock of birds in the middle of the runway ahead. They were flycatchers as far as I could tell. At the approaching bigger metal bird they scattered, but unfortunately one decided to challenge my propellor to a duel. Maybe he thought I was a big fly.

So as I rotated and the aircraft wheels left the ground, something yellowy-red and mushy appeared on the right-hand side of the windscreen, accompanied by a soft "phlat", the sort of noise that Rowan Atkinson might make when in character as Johnnie English or Mr. Bean.

I quickly glanced at the temperature and pressure guages, and all seemed well, so I continued the take-off and climbed up to circuit height to consider what to do. Since the bird was small, the deposit on the windscreen did not affect my forward vision, and there were no adverse engine indications, I decided to continue climbing and head back to Nairobi.

Windscreen Damage from a Vulture

As is always the case, these issues require judgement on the part of the pilot. If the bird had been bigger or there had been multiple strikes, I would have continued in the circuit and landed. Had the windscreen or propellor sustained physical damage, such as shown on the aircraft on the right, I would have aborted the take-off (even with the wheels already off the ground) and landed back on the runway. It is long enough to do that.

A week later one of my colleages was flying to Dadaab and he had a birdstrike. Another flycatcher. His Cessna Caravan has a big engine air-intake at the front, and the concern is that a bird could be ingested in the engine and cause a failure (as happened with the airliner that successfully ditched in the Hudson river a couple of years ago). In this case he aborted the take-off, shut the aircraft down and had a good look in the air-intake.

So I've had my first birdstrike. Happily as with the majority of birdstrikes, it was not a serious incident (except of course for the bird). Next time I'll tell you what happened when I got up close and personal with some low cloud...