The Wasp Nest

The end of the rainy season was close, early on a tropical December morning, when I took a new Nestlé employee in my Cessna 150 from the interiór to Panama City for a day of shopping.
I set the electric landing flaps to full down on short final to the City airport's runway 21. Nothing happened.
After the first few seconds of adrenaline flow, the cause was easy to identify as a blown fuse in the flap motor's circuit.
Fumbling in the glove compartment for the correct spare fuse, I lost precious time and was fast approaching the far end of the runway.
As most often is the case in aviation's potentially dangerous situations, at least two abnormal circumstances had to meet, if the incident is was to develop into an accident. In this case, landing with no flaps at all would not have presented a problem in itself. But in addition, I had entered a high final to clear the buildings in the approach path, again in itself not a problem. The two facts together, however, made up one of the very close calls in my flying career.

With one hundred meters of runway left, at full gross weight, and applying full power the little two-seater would not climb a foot per minute. There was just no way except flying straight ahead. The nearest land straight ahead is Australia.
So I tried a slow 180 ° turn towards the coast, which cost me another 20 feet of precious altitude.
With my meagre 250 flying hours I was too busy to remember calling Panama Tower about my problem and that I was attempting to land in the opposite direction.
There are a few rocks looming out of the surf near the coast at the South end of the runway and I had a feeling of flying below them. As far as I can remember, this is the only time I made a landing without the need to level off. The tyres just went "chew-chew" and we were safely on the ground.

 The reason for the fuse to blow came as a surprise as we examined the flaps system back safely on the ground.
Cessna specifies so-called slow-blow fuses for the flaps. As it is impossible to read their ampère rating in flight, especially in an emergency, I had marked all the old fashioned thermal spare fuses with Dymo Tape. But a slo-blo fuse was not among them. Despite my constant bickering at the maintenance shop, they had simply been unavailable in the Republic.
But what made the fuse blow in the first place? Opening the inspection plates showed a reddish brown mass of cement between the flap cable and one of the pulleys, later identified as the nest of a tropical wasp.

I'm afraid my passenger-colleague preferred to attribute the incident to the whims of personal flying rather than an act of Murphy's.

 What to learn from this incident?

1. Tropical wasps' saliva plus earth mix to very hard concrete indeed.
2. Inspection plates are no barrier to mating insects.
3. Avoid high approaches unless the ground at the runway's end is level.
4. While a normal type instead of a slow-blow fuse is not a no-go item, one had best keep shortcomings like this in mind during flights at all time.

 Thankfully, we now all have magnetic pop-out fuses, so romantically called "circuit breakers".

8. December 1968

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