Apple should start making airports and airplanes IMHO :)

A few nanometers thick layer of piezo-resistive skin could perhaps also be seen as an alternative ;)

Processing the data would require some dense continuous computing but this method should give a very reliable and precise IAS reading.

Until the present Thales/Airbus situation, pitot tubes have been very reliable.

It just shows that manufacturing even the simplest device can be screwed up. What could possibly go wrong with making and maintaining piezo-electric skin?

GB

vortex shedding
 

a few years ago I believe work was being done on speed sensors which relied on 'vortex shedding ' (why telephone lines 'sing' in the wind). These don't rely on dynamic pressure. Don't know what, if anything, became of them.

here you go...
 

1) 'Print' film with micro connectors onto the wing surface

2) Paint job

:)

The sensor surface shouldn't require any more maintenance than say a carbon fiber airframe.

...As a secondary and auxiliary meter, the IAS could be derived from an internal 3D reading of the wing geometry together with weight, static pressure and accelerometer data.

Pls tell me you are having a lend of us :hmm:
or from what galaxy you lobbed in from?:eek:

Ha ha :)

(I'm from Concerned Non-frequent Fliers Anonymous)

Advanced automation within aviation is the future and thus the need for a more sensible airframe.

Are you seriously suggesting to try to back out the external wing loading from FEM type measurements within the structure? That would require a degree of accuracy that simply does not exist, and may not feasibly ever exist in any cost-effective sense.

First, a piezo-resistive matrix on the wing surfaces would give data that eventually could be used to make flying in strong turbulence experienced as rather comfortable.

There would be a combination of inputs needed, with advanced realtime computing involved, surely. A carbon fiber airframe would have more flexing / movement that would make the measurements more 'visible' to the various sensors.

The main 3D physical motion of a wing could be measured from one strategic single point, affordably.

You can't deduce airspeed from the data you are suggesting, though.

At least, not with any expectation of accuracy.

A wing flexes the same under load to support the same weight, independent of airspeed (to a first approximation). So the wing shape at 100knots and the wing shape at 200knots would be essentially identical for the same weight. Even then, backing out the weight would not be trivial, especially given the unknowns of the inertia distribution due to fuel and payload distribution. (The wing flex for a heavy a/c with low fule state will differ from that with a high fuel load but correspondingly lower payload)

So, let's assume nevertheless that somehow we back out a reliable estimate for the weight. What's left in the lift equation - 1/2 rho V squared, S and CL. OK, S we can define, but to get closer to V we need CL. For that we're going to need an accurate model of the aerodynamics - not at all trivial, especially for an in-service aircraft not given the TLC a test vehicle gets. (Indeed, this methiod has been used with a KNOWN V to estimate degradation of CL compared to standard, and it's not always small).

I think if you do the error budgets in that process you struggle to get any kind of accuracy for airspeed - especially given that we have a pretty good way of measuring it right now that's a great deal simpler.

The alternative - Well, you could attempt to deduce the airspeed by looking at very small differences in wing loading due to low order Mach effects - not something terribly accurate at low Mach numbers. But that's even more error prone I suspect.

The model would be complex, and this 'synthesized IAS' could be thought of as a complementary reading, used when there was an eventual problem with the main meter.

The resistance will here be quadrupled and this will bend the wing accordingly.

The accelerometer data is meant to make the reading / the modeling more accurate.

(I dropped out of school long before any of the above and we only had access to an ABC 80 btw :bored:

A friend, John Talbot, has designed a simple system where a valve shuts off the ASI from the pitot tube and engine bleed air is blown back through the pitot system to the pitot head, clearing any ice, moisture, insects, etc. If this is done on each pitot head one at a time by a sequence system of some kind the ASI reading will not be lost.
The patent for this is now in the public domain so a developer would not have to pay royalties, etc. but I`m sure John would appreciate an acknowledgement. We have tried sending the idea to most of the manufacturers but no luck so far.
Publication number:
GB2418739
Publication date:
2006-04-05


Details can be found on

http://v3.espacenet.com/textdes?DB=EPODOC&IDX=GB2418739&F=0&QPN=GB2418739

No. Although the dynamic pressure is 4 times greater at 200knots compared to 100 knots, the wing loading is actually the same. Because the wing is supporting the same aircraft weight, and THAT is what causes the bending.

xMillion dollars worth of electronics being fed information by a couple of holes in the side of an aircraft.
I know its not as simple as that but its a question of balance.
Takes me back to my days in industry when the time and motion engineer would measure operations to the nearest minute then produce costings to a thousanth of a penny! He didn't understand the problem but common sense......
It is actually quite serious because we now have a very good indication that something wrong with these 'holes' can totally disable a large aircraft and that 'something' can be a problem encountered regularly by all pilots i.e. ice.

Why is it only Airbus receiving attention for multiple pitot problems?

l@ser...
 

Customs...... "The Traditional Monkey" ;)

P.S.: I wonder if it could be applied to machines somehow...

In industry terms, it isn't "only Airbus".

EASA Safety Information Bulletin 2009-17, issued June 09, contains "recommendations" to operators regarding unreliable airspeed procedures and the applicability is:

Now obviously the more general media are concentrating on AB because that's the simple story. And to be honest, would it really help matters if the press started harping on "it could happen to Boeing too, or Douglas, or ..."? There's enough unnecessary anguish already.