Monthly
Discussion
Airplanes,
Aviation Technologies, and Our Need to Travel
Much
talked about recent events such as the Concord crash, the Farnborough air show,
and the Airbus super jumbo (A3XX) call for a big-picture update of related issues
previously discussed in Predictions
and Conquering Uncertainty.
To begin with, I want to remind the reader of some
insights revealed by using S-curves and the concept of Darwinian competition in
social and market activities. For example, when a large S-shaped curve was
decomposed into smaller ones, see Exhibit 3 below.
Exhibit 3. An overall S-shaped pattern decomposed into constituent S-shaped
curves according to a rigorous procedure. The horizontal axis represents time.
At the bottom of the figure we see the life cycles corresponding to the
constituent S-curves.
S-curves are nested like Russian dolls.
Consequently, one finds many products in a product family, many product
families in a company, many companies in an industry, and many industries in
the global economy. In all cases, the growth process follows the same S-shaped
pattern but the time frames are different, and the corresponding life cycles
have different duration. Life cycles are longer during the high-growth period
of the overall curve and shorter during the low-growth periods in the beginning
and at the end, as sketched in the bottom of Exhibit 3.
An example of nested S-curves can be
found in the aviation industry. Wide-body aircraft can be seen as a family with
about a dozen members, each having its own life cycle. Early members, such as
the DC10 and Lockheed Tristar, were shorter lived than the Boeing 747. On the
other hand, the recent rapid appearance of the 767, a number of Airbuses, MD11,
and 777 implies that these aircraft will have shorter life cycles than the 747.
As in the pattern of Exhibit 3, the wide-body family of aircraft underwent
successively the stages of: two short life cycles, one long, and again a number
of short ones. We can thus conclude that the overall S-curve, describing the
growth process of the wide-body family, is approaching a ceiling, with the 747
as the central long-lived product. In the future, we should expect little—if
any—growth in the annual passenger-mile totals of wide-body aircraft. In fact,
the average size of airliners on transatlantic flights has already shown signs
of decline. In that light, the super-jumbo underway by Airbus, the A3XX, has a
doubtful market. This aircraft will have to steal market share from the
high-capacity aircrafts in use, and even then, its sales would never reach the
hundreds of units anticipated by Airbus managers.
But let us zoom back and look at all
of jet aviation as one family with two as yet members. The first one—early
jets—underwent a 15-year long growth process. The second one—wide
bodies—underwent a 30-year long growth process. Since the life cycles of the
constituent S-curves are increasing, the picture suggests that we are still
before the mid point of the overall curve and that there should be a new
upcoming type of aircraft with an even longer life cycle.* What should this type of aircraft look like?
Communities grow around their
transport systems. According to a traveling innvariant discussed in Predictions, people are happiest when
they are on the move for an average of about 70 minutes per day. If it takes
more than seventy minutes to get from one point to another, the two points
should not reasonably belong to the same "town.” Cars permitted towns to
expand. When people only traveled on foot, at three miles per hour, towns
consisted of villages not much larger than three miles in diameter.
There was a factor of ten in speed
between foot and car transport, but also between car and airplane transport,
taking the average airplane speed as around 300 miles per hour. Airplanes
expanded the limits of urban areas further and it is possible today to work in
one city and live in another. Air shuttle services have effectively transformed
pairs or groups of cities in the United States, Europe and
Japan
into large "towns."
If we now imagine the supersonic
airplane of the future with an additional factor of ten in speed, say an
average of 3,000 miles per hour, we can visualize the whole Western world as
one town. In his book Megatrends ,
John Naisbitt claims that Marshall McLuhan's "world village" was
realized when communication satellites linked the world together
informationally. This is not quite accurate. Information exchange is a
necessary but not a sufficient condition. It is true that empires in antiquity
broke up when they grew so large that it took more than two weeks to transmit a
message from one end to the other. But it is also true that communications
media are poor substitutes for personal contact. The condition for a
"world village" is that it should take not much more than one hour to
physically reach any location.
Expanding in space as far as possible
is of primordial importance for all species. It is what reproducing unicellular
amoebas are after, as well as what the conquest of the West and space explorations
were all about. According to this reasoning supersonic travel and the
realization of "world village" become inevitable. But there are
constraints. Productivity can not be compromised. As with the standard of
living, decrease is not an option for a new way of life. The productivity of a
new-technology aircraft (i.e., the product speed times payload) must increase.
This was not the case with the Concord whose productivity significantly fell
short of the productivity of the Boeing 747 introduced around the same time.
The Concord's payload was too small. It should be able to carry around 250
passengers to match the productivity of wide-body aircraft. And even with 100
passengers the time the Concord gained flying, it lost refueling. This explains
its commercial failure.
Other insights revealed by S-curves
are found in Exhibit 4 depicting the beginning of chaos. By casting the
analytical mathematical expression of the S-curve into a discrete formulation,
we observe chaotic fluctuations appearing at both ends of the growth process.
In Exhibit 4 we see the onset of chaos, for a certain combination of the
parameters values. At this point, chaos is not fully installed yet, but there
is an important oscillation both in the beginning and at the S-curve. In real-life
situations we cannot see the early oscillation completely because negative
values have no physical meaning. We see, however, a precursor followed by an
accelerated growth rate, an overshoot of the ceiling, and finally erratic
fluctuations. These features correspond to real phenomena. Accelerated growth
is a catching-up effect, usually attributed to pent-up demand. The overshoot is
a typical introduction into the steady state. As for the precursor, it is often
considered a fiasco, unfairly so.
Exhibit 4. One of the first patterns obtained by putting an S-shaped curve in
a discrete mathematical form. The deviations from the familiar S-curve
demonstrate the early catching-up effect, the precursor, and the overshoot.
According to our earlier discussion,
the Airbus A3XX corresponds to the "overshoot" of the growth process
of the wide-body family of aircraft. As for the Concord, it corresponds to the
"precursor" of the next family of aircraft, the supersonic family.
Sticking to Exhibit 4 we can say that after the Concord there will be no
supersonic commercial travel for a while (a duration comparable to the life
time of the Concord, i.e., 30 years). But then supersonic travel will take off
and will grow at an accelerated rate (pent-up demand). From the discussion
around Exhibit 3 we can surmise that this new family of supersonic aircraft
will have a life cycle longer than thirty years, and will constitute the
central long-lived family of aircraft in jet aviation.
To do this successfully, supersonic aircraft
technology will have to rely on a richer fuel, such as liquid natural gas or
liquid hydrogen (see last month's discussion topic). This fuel will permit high
productivity, namely, supersonic speeds as well as relatively high carrying
capacity, but probably narrow fuselage (single corridor). Last but not least,
the hydrogen fuel will do marvels for the environment. Let us leave aside, for
the time being, the fact that the most realistic way of producing and
liquefying hydrogen in such quantities today is via nuclear energy!