PPRuNe Forums - View Single Post - LOT Boeing 767 severe turbulence and unreliable airspeed June 19th
Old 9th Nov 2011, 14:09
  #17 (permalink)  
SadPole
 
Join Date: Jun 2010
Location: East of Eden
Posts: 157
Likes: 0
Received 0 Likes on 0 Posts
I'm sure that if this had been from manufacturer 'A' rather than manufacturer 'B' there would be media hysteria.
It has nothing to do with manufacturers and everything to do with the fact that a bunch of dead buddies makes it much better story to pursue in the case of 'A'. It's stupid, yes, but this is why the web has a chance to change things, eliminating monopoly of the usual tabloids.

There are more idiocies like that. In the present world a military pilot that gets shot down becomes a celebrity and a millionaire while the one that does not get shot down remains poor.

That said, I often wondered why on earth the avaition industry does not get rid of these idiotic pitot tubes altogether or at least have a backup of a different type. We now have much more reliable ways to measure air speed. For example this:

Mass flow sensor - Wikipedia, the free encyclopedia

Yes, mass flow sensor measures mass flow, but electronics can easily calculate speed if you know the current air pressure and temperature - which every plane has to know.

Unlike pitot tube, the mass sensor cannot freeze, it is much less prone to contamination, and it is far more precise. Almost every car currently produced uses those and nobody would even think of using something like a pitot tube in their place, in spite of the fact that pitot tubes are significantly cheaper.

The theory of operation of such a sensor is quite simple - you heat a piece of metal and measure how much energy you require to keep it at a constant temperature. The more air flows over the sensor, the more energy is required to keep it at constant temperature. An aviation version of such a sensor could simply be a piece of wire/metal rod protruding from fuselage.
SadPole is offline