Sunday, 18 April 2010

Enough is enough

Yesterday a KLM Boeing 737 took off from Amsterdam, climbed all the way to 41,000 ft and came back down again. Why? To observe and detect the ash cloud that is supposedly spread over much of northern Europe. What did they find? ash was detected. The aircraft was spotlessly clean when it returned to Amsterdam.

The satellite imagery that I have seen on the net is pretty inconclusive. Clearly the ash cannot be physically seen in the air so we are reliant on infra red imagery to detect it. Yet the imagery from the Met Office shows the "significant levels" way to the north of the UK

The case that the news items always relate back to is that of the British Airways 747 which suffered multiple engine failure over Indonesia....but in that instance the cloud was all too visible to the crew with visibility severely restricted. Clearly that is not the case now, or again the ash cloud would show up using standard optical imagery...besides which we would easily see it from the ground.

The met office sent an aircraft up....but only in to the lower levels that jets would climb through...not levels at which they actually operate. Yes, they said that they detected "significant" ash, but the aircraft was not exactly covered in the stuff when it returned. But, that aircraft only operated at levels that private flights are still being allowed to operate in otherwords they detected ash at low levels, but the CAA has not considered it sufficient to ban private flghts! How then, can they justify banning flights at higher fleght levels?

In truth of course there has been volcanic ash in the atmosphere since the planet formed; the question is "What density is significant?
" No-one so far has provided an answer to that question. Surely with all our technical abilities and resources that question can be answered or at least someone can say that the levels are currently in excess of that which aircraft engines can safely operate?

Every year we have several incidents where huge volumes of Saharan dust blow up into the stratosphere, clearly visible on all optical satellite images. On occassions this has found its way all the way north to the UK. When it has fallen to low level, it produces a very murky sky, and we see hard evidence by the dust covering our cars. Yet in these circumstances flights operate as normal, they fly through the dust, and so far without any damage being caused.

The VAAC (Volcanic Ash Advisory Centre) has said that the ash cloud is 60% Silica. Guess what the sand from the Sahara is made of? In reality I fear that it is simply a case of, yes there is some ash up there, the public know that an aircraft nearly crashed once because it flew through ash, so lets just ban all flights...that way no-one is responsible if there is an incident.

There are aircraft available with testing equipment that could be used to give accurate readings of the ash levels up there. The aircraft concerned are operated by NASA. Have we, or any affected country asked them for assistance?

In the meantime the public suffer, businesses suffer and whole aviation industry suffers.


  1. Ken, did you forget about the KLM 747 that lost all 4 engines over Mt St Helens? Hard to believe that was 30 yrs ago! US press has referred to both incidents.


  2. You're quite right but not being a British aircraft its not newsworthy here!

    The incident was very much like the BA one, where the visibility was severely impaired by the ash particles.