AF 447 Thread No. 8

[RR_NDB]

Advantages of two SS with no feedback

Hi,

aguadalte

Some time ago you mentioned in an excellent post to CONF iture (*) some points that could clarify an issue:

Why AI (Airbus SAS) introduced the SS?

This issue is being covered in another Thread concerning the "interface". The paper you mention discuss the issue and is a confirmation of some concerns i had previously.

Could you help me to understand why Airbus Industries (Airbus SAS) introduced two separated SS with no feedback in their planes?

There are advantages with this design?

Reasons for AI SS introduction to airliners

Hi,

Why AI (Airbus SAS) introduced the SS? What reason(s)?

It was representative (the visible item) of the Airbus new control philosophy?

What are the main advantages? And it's disadvantages?

What about the overall cost to benefit compared to original (proven) solution?

This interface is adequate when dealing with possible anomalies?

Why active feedback was not built in?

A similar device would be eventually adopted by Airbus SAS competitor(s)?

I mentioned my post in the specific thread avoiding to discuss the issue in AF447 thread. I don't consider the interface an issue between A or B. My agenda is on Aviation Safety, during normal conditions and during anomalies.

PS

The mentioned Thread:

Man-machine interface and anomalies

The increasing technological sophistication in FBW planes brings benefits and challenges to the pilots and other 'players". The objective here is to discuss the "interface" and it´s components, specially when facing anomalies.

(*)

CONF iture:
The provocative answer to that question would be: "because Airbuses were designed by engineers but unfortunately flown by pilots"...
My personal guess is that they wanted to brake with the "old" concepts. Starting with a blank sheet, they wanted to show the world that they were able to design an all new aircraft reflecting the European potential for innovation. "An aircraft made against pilot's errors"...
I had the opportunity to meet Pierre Baud, when I was invited to Toulouse in the early ninety's, to fly one of their A330 testbed aircraft. That was my first experience with a FBW aircraft (before that, only Boeing and A310's) and I personally had the chance to verbalize my worries in this regard (no feed-back on SS, added inputs on SS, lack of need for trimming, ATS in step of Auto-Throttles) and he explained to me that this was a new concept of aircraft and that the FBW represented not only an evolution on the handling characteristics but also the chance to save on weight and that the final goal would be MFF and communality.
I do understand that at certain point of the design work, AI engineers had to take options. They have opted for this system and there is no go-back, at this time. It is not yet clear for the majority of the pilot's community that the system is wrong.