In Lanzarote, as in many other parts of the Spanish geography, a most curious phenomenon is taking place. Politicians manage to convince public opinion of the need to carry out a series of pharaonic works whose amount could very well be invested in things that require that public money but that are not as "sellable" as the works in question.
A few days ago our 'dear leader' Mr. San Ginés poured into the press his particular vision of what should be done with the runway at Lanzarote Airport. Urged by the Lanzarote Chamber of Commerce - which groups builders and all kinds of tourist entrepreneurs, who are obviously in favor of the expansion, whether necessary or not - he requested an immediate meeting with the Minister of Development, exposing the technical reasons to the citizens who obviously cannot verify the veracity of these arguments, to expand the runway of Lanzarote.
It so happens that I do have that knowledge and I am enormously surprised by the lack of shame with which things are proceeding here. It is a crude deception of the citizens to affirm that we are going to have more or better tourism due to a 400m runway extension.
I am therefore going to give you - performance tables in hand - concrete data. This data is for a commercial aircraft of the Embraer brand (with 120 seats, comparable to the 737-400).
Before I tell you anything, you should know that take-off operations are more critical in practically all commercial operations... Or what is the same: it is more critical to take off than to land. We will therefore reach our aircraft limits earlier on take-off than on landing.
Why is that? Because for air safety, the worst case scenario is always assumed in a take-off: the failure of an engine at a speed at which the aircraft could not stop on the runway.
That speed is called V1. Before reaching the speed of V1, the pilots know that the remaining runway is sufficient to stop the aircraft safely. After that speed, you have to take flight, yes or yes. For take-off calculations, it is therefore assumed that the most critical engine for the operation fails at just that speed.
With that condition it is mandatory by law that the aircraft crosses the obstacles.
I am therefore going to the simplified table of the aircraft for take-off from a runway at sea level and I look at what is the maximum weight that my aircraft can take out in certain circumstances. Let's take Flap 4 (it is the high-lift device of the wings, at its maximum value) and 40°C of temperature. We see that the weights for runways of 2000m, 2200m, 2400m, 2600m and 2800m respectively are: 45137kg, 45137kg, 45137kg, 45137kg and 45137kg. Curious, isn't it? No, I haven't made a mistake. They are all the same. In other words. We are not going to take out even a kilo more of cargo for being the longest runway of 2000m!
The acceleration distance stopped for those conditions is 2072m by the way - in case anyone wanted to know, since we have talked about it. The climb gradient of the aircraft is around 15% for those conditions and the minimum required by the airport's SID sheet (published in AIP) is 7%.
Of course, it must be said clearly. This is an example based on a specific aircraft. But the performances of the aircraft are normally made for similar conditions. A larger aircraft, having larger engines, also has more power to take out that additional weight that its size gives it.
Mr. San Ginés says that the size of the runway "poses a severe threat to the projection and competitiveness of Lanzarote as a tourist destination, in addition to slowing down our intentions to expand and diversify tourist markets, whose foreseeable connection route will materialize with aircraft that require infrastructures that the island lacks".
And now I say: if we have received 747s (Jumbos so we understand each other), the A330 of Air Berlin and Air Europa regularly comes and on occasions we have had the visit of Ilushin, Tupolev and even the Concorde... what aircraft is Mr. San Ginés referring to? An A380? I'm sorry to disappoint you Mr. San Ginés, but the A380 only goes on very few occasions to Madrid or Barcelona. You will never see that plane in Lanzarote. I am not even going to talk about the limits of the Lanzarote pavement, which would also have to be taken into account to receive aircraft with more weight in Lanzarote. For those who are interested: http://es.wikipedia.org/wiki/Número_de_Clasificación_de_Pavimento http://es.wikipedia.org/wiki/Número_de_Clasificación_de_Aeronaves
And let me not be misinterpreted here. I want more tourists and merchandise to come and for Lanzarote to be a bustling international commercial center. But I do not believe that the extension of the runway contributes to this, nor that it compensates for that expenditure of money that we could well invest in something that we all notice and not just a few.
And now knowing those data, doesn't it seem a bit strange that the builders and their 'friends' politicians demand with such insistence an infrastructure that is clearly unnecessary?
