Precautionary Landing

Shaken but not stirred is how I like my Martini, not my plane. Yesterday was a bit of shaken though as I took off on runway 05 Virginia for a flight to Howick. My daughter Kate-Lynn has organised a little surprise for her boyfriend James. I was to take him unannounced on a 45 minute flight inland to our midlands area of the Province where she was going to meet up in her car and we were going to do the Midlands Meander and lunch in the farming and craft area around Howick, also famous for our Howick Falls... a waterfall on the Umgeni River below Midmar Dam, the main water supply for our Province.

Everything seemed normal as I did my mags check and pre-takeoff checks and I ran through the emergency procedures with James... should there be any abnormality on take-off I would re-land the plane on the runway if there was space remaining, failing that would hop over the bushes that separate the runway from the beach and land on the beach, or if it was possible we would do a low-level circuit and return to the airfield. I pointed out where the fire extinguisher was located behind the ledge at his elbow and pointed out that to detach it, he would need to lift the clip and remove the extinguisher from the bracket. I also told him not to touch any of the controls and that I would take charge of any emergency... not actually anticipating that we would follow these procedures today.

ATC gave us the cleared take-off announcement and we edged onto the runway, lined up and did a last-minute re-check of engine temperatures, flap setting and harnesses and checked with James that we were ok to roll...

I gently squeezed on the power while maintaining course along the centre line, then put the throttle into full power position and watched the speed increase anticipating rotation/take-off at 45 kts (83 kmh). It seemed to take a fraction longer than anticipated to build up speed as we were eating up the runway. As we reached 45 kts I had half a hesitation, but only half as to whether I was imagining it or that we had taken further than normal to get to take-off speed. I gently lifted the plane off the runway and then as normal I held the stick slightly forward to flatten the climb to enable the plane to build up more speed before climbing. But nothing happened. In fact we reduced speed to 39 kts which means the plane should not be sustaining flight. The EFIS warning light was flashing and the audio warning "LOW SPEED" was sounding. It usually does this as we are building up speed down the runway and when it did then I made a mental note to warn a future passenger not to be alarmed as the low speed warning was normal until we had built up enough speed for flight. However this warning was now sounding regularly as we skimmed low over the tiny bit of runway left... certainly not enough to reland the plane. I skimmed over the trees at the end of the runway at only 100ft instead of the 300ft we should have been at now and took a gentle turn to the beach. A bit of a panic had set in as I had never experienced this before. The engine was sounding normal though so I was determined to see the airspeed climb as normal to 70kts which would be the best rate of climb speed for this plane. I was now over the beach, still at 100 ft and the engine was sounding ok. I knew I needed to do something while the engine was still alive and we were still in the air. I must fly the plane. So I started a gentle turn out over the sea to return to the airfield, conscious of not wanting to stall the plane in the air at that low speed, nor wanting to ditch in the sea. I realised that in order to prevent a stall I needed to make the turn as gentle as possible which meant a wider circle and by now we were out to sea almost as far as the shark nets. I reassured James that we weren't achieving the best flying speed I was happy with and we were returning to land. At this stage I called the ACT at Virginia and said we needed to return immediately to the airfield and could I have clearance to land. She asked what the problem was and whether I needed emergency vehicles for a crash landing. By this stage the airspeed had increased to 70kts but inexplicably the engine revs were showing 6700 which is impossibly high. The take-off specs for the Rotax engine are 5800 revs for a maximum of 5 minutes and 5400 continuous. One would normally have reached cruising speed by this stage and one would turn the constant speed propeller setting to cruise so that the revs reduce and stabilise around 5000 revs per minute. I was at a loss to understand what was happening but used the increased speed to gain a little height and I reduced the throttle setting to try and bring the revs down as they were indicating a possible imminent engine failure. I was just thankful that the engine was indeed performing and getting us back to the other end of the runway so that we could turn onto final approach and reland the plane back in the direction we had taken off in against the wind and as slow as possible. Getting us back on to finals was a huge relief and I was thankful to see tarmac ahead of us. We touched down as normally as possible and I was hoping that James did not see anything too untoward about the flight. My mind was racing to consider all possibilities and as to what had just happened.


I landed back on runway 05

In retrospect I have come up with a few possibilities and am thankful to have had a safe experience which has taught me a few lessons and re-programmed my head to do a few things differently should something like this happen again.

1. If I ever feel uncomfortable again as I did for a split-second on take-off, rather abort the take-off than take to the air. This is easier said than done if there is little runway left, but I have made a conscious decision to analyse a runway I intend to take off from in future to pre-decide what would be the latest decision point for a take-off. This also depends on the wind speed and direction.

2. Most importantly, instead of being fixated on the readings given by the computer screen of the EFIS I need to read my backup instruments for confirmation of what I am reading. I intend to put a little marker on my pressure instrument - the airspeed indicator - at the 45 kts mark for take-off and the 70 kts mark for climb speed. Whilst these instruments are quite tiny and difficult to read at a glance, a glance to check if the speed is between the two markers would be all I need to confirm whether the computer instrument is giving the correct reading. My feeling is that the recent electrical fault we had could have perhaps damaged the sender unit on the EFIS so that the incorrect airspeed and engine revs were being displayed. The engine could possibly have been performing perfectly, just the readout gave me the mistaken impression that we were in imminent danger of an engine failure and were about to fall out of the sky due to the lack of speed.



This is what our EFIS looks like and the position of the AirSpeed indicator and the engine Rev Counter

 I intend to go back during the week and do a runway check.. speeding down the runway with the intention of not taking off but comparing the speed readouts of the EFIS and the pressure instrument to see if there is any deviation. This will give me some clue.

So all in all, possibly nothing wrong with the plane's engine at all, possibly just an EFIS (Electronic Flight Information System) readout error and a good learning curve for me. The Captain Morgan's and coke certainly tasted good after this!