Re: A320 cockpit visit)

From: (Stefano Pagiola)
Organization: DSO, Stanford University
Date:         28 Jun 93 22:34:51 PDT
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Robert Dorsett <> writes
> 1.  The A320 should be compared to aircraft with similar avionics
> and operating philosophies: [747-400, 757, 767, A300-600, A310]

I'm not sure what `similar' means in this context but it seems to me  
that the A320 isn't really comparable to any of these designs.  Yes,  
they all have `glass' cockpits and digital avionics (as do the MD-88,  
MD-11, and Fokker 100), but none of the other designs is FBW, and  
none attempts to give the kind of `protection from errors' that the  
A320 attempts (what Bob Dorsett called the `cocoon' approach).  The  
A320 will be comparable to the 777, when it comes out.  I fully  
expect the 777 to compare favorably, if only because Boeing could  
draw on 5 years of A320 experience.   (Also because Boeing doesn't  
tend, in my experience, to be quite as arrogant about these things as  
Airbus can be.)  But for now, lets not compare apples and oranges.

> 2.  The 727 situation was a different era, and should be viewed
> accordingly.  The pilots were upgrading to *jets*, and had no
> experience with jets....
> Now, Airbus, of course, would have us believe that *its* interface
> is the "future" of jet transport, and, if we accept that, then
> its accident rate is as easily "justified."  The problem here,
> though, is that they haven't changed that much about airplanes
> fly--only how they're flown--and NOBODY else is jumping on the
> same bandwagon.  The FBW is proprietary, and their control laws
> are unique.  They are vaguely similar to what Boeing was con-
> sidering on the 7J7, but guess what--Boeing's opting for a
> "conventional" control law and interfaces on the 777.

Rephrase that a little and it won't seem so bad: Airbus believed (and  
probably still does) that its interface approach was the future.  It  
was, in fact, one possible future.   Whether it was (or is) the best  
possible future is clearly subject to debate, but it is not, IMHO, a  
debate that can be undertaken a priori.  You have to try it to see.   
I think Airbus deserves praise for attempting the transition to a new  
way of flying.  I think they deserve censure for appearing to be so  
unwilling to learn.  A bit like Columbus insisting he had really  
found India 20 years after he found America.

> It's really a question of philosophies.  There are two major
> philosophies for the future (three, if you count keeping things
> like they are).
> The first is to continue with the automation of technology, and
> isolate the pilot.... There is strong evidence that insulated
> pilots tend to become careless pilots, "out of the loop."
> The other approach is to "keep" the pilot in the loop, yet somehow
> "protect" the airplane from his mistakes.  This is the "cocoon"
> approach...   This may be undesirable, too, in that the pilot
> may grow to rely on the "protections" being there to save his
> bacon.

Well put.  I think the latter approach is inevitable.  I think  
technology does let us build in safeguards that are helpful and  
useful.  The lowly stick shaker was an early example of this, but it  
could only alert.  Technology is reaching the point were it can do  
more, and it would be silly not to use it.  But in doing so, we have  
to be very wary to not lock pilots out of the loop and make them  
overconfident.  Walking that fine line isn't going to be easy.  What  
I worry is not that Airbus is trying to walk it, its that its doing  
so with the wrong attitude; with too much confidence in its technical  
capabilities and not enough consideration for human factors.

> If you are aware of the
> problem, you can work around it; if not, you can fall victim to
> the environment and make a mistake that kills you and your
> passengers.

As I said, I think most A320 pilots are, at this point, aware of the  
potential pitfalls and treat them with respect.  That's why I don't  
lose any sleep over flying on A320s.  But I hope it doesn't take a  
periodic crash to keep people watchful.

Stefano Pagiola
Food Research Institute, Stanford University (NeXTMail encouraged) (NeXTMail encouraged)