OCTOBER, 1961
THE PIEDMONITOR
PAGE FIVE
Building A Schedule Is No Simple Job
A4any Elements
To Consider
Last in a two-part series on Airline
Scheduling.
Suppose you were givgn a group of
airline routes and cities to be served
and told to construct a flight schedule.
How would you start? What require
ments would you have to consider?
overs, or training additional crews when
there are enough already for maximum
fleet utilization. You can see, too, how
even a 15-minute arrival or departure
time change could cause any one of
these things.
Gate capacity presents a challenge. If
you have all your gates filled during the
noontime at a certain city, obviously
something will just have to “give” if
you hope to run another flight through
that city at that time of day.
WHY SCHEDULES CHANGE
9 New Airplanes
# Aircraft Modification Programs
# Changes in Maintenance Programs
# Government Route Changes
0 Competitors' Actions
9 Experience with a New Service
#Airpoit Construction
Preston Wilbourne, Director of Tariffs
and Schedules, lists five basic steps you
would have to take in starting a sched
ule from scratch:
(1) Determine the number of flights
from point to point.
(2) Determine and set up the best ar
rival and departure times.
(3) Allow sufficient ground time and
fuel stops.
(4) Figure return time so aircraft can
originate other flights at destina
tion cities and check on incoming
flights from other airlines to guard
against gate congestion.
(5) Build flights around each other in
an interlocking pattern.
Full Equipment Use
“You should schedule airplanes to get
the most passengers in the least time,”
adds Wilbourne, “and get maximum utili
zation of equipment compatible with
maintenance, station, and crew over
nighting requirements.”
Maintenance, station, and crew require
ments — these are three of the prime
factors you would have to consider in
setting up your schedule.
Look at maintenance. As you know,
each plane in our fleet undergoes care
ful inspection and maintenance accord
ing to an exacting timetable. If a plane
were to fly beyond a maintenance time
limit, it could not continue in service
until the work was performed. This
means each plane must be routed around
our system in such a way that it arrives
at a maintenance base in accordance
with its maintenance timetable.
To achieve this, the maintenance de
partment, working closely with our
schedule planners, prepares highly de
tailed aircraft routing charts. The result
is a master plan that provides timely
maintenance of our entire fleet as it tra
verses the system on its day-in day-out
mission of public service.
Flight Crews
Limits on flight crews often dictate
what schedule planners can and cannot
do. For example, pilots can fly no more
than eight hours a day; nor can they
exceed 30 flight hours during any seven-
consecutive-day period.
An airline must take a good, hard look
at a proposed schedule that calls for
excessive crew changes, or excessive lay
Flight Peaking in the Public Interest
In recent months criticism has been
mounting over the practice of “flight
peaking.” A critic might exaggerate
peaking like this:
“I go out to the airport around 5 p.m.
and I see airplanes all over the place.
But when I want a flight around 3:30
p.m., there’s not a plane in sight.”
The truth is that peaking is a vital
public service. It means that the airlines
are flying when the most people want to
go.
Because of the air age, the business
man, who accounts for a large share of
our patronage, can now leave at the
close of a day’s work and arrive at his
destination at a respectable hour. This
is further borne out by the habits of
private and business aircraft owners.
The post office reports similar peaking
patterns in hourly movements of the
mails.
People Peak
So — in the interest of serving the
most people — airlines schedule their
services to a great extent at times when
the majority of air travelers are on the
move. This means a greater measure of
flight activity around the early hours
in the morning, afternoon, and evening.
For example, between 2:18 p.m. and
3:20 p.m. there are six flights out of
Roanoke. Why? “Because,” says Wil
bourne, “the history of traffic flow on
these flights indicates they carry ex
ceptionally good loads.” In other words,
people peak during 2:18 and 3:20 at
Roanoke.
“Lean” Hours
Though more flights are scheduled at
peak hours, this is not to suggest air
lines do not schedule “off period” serv
ices. They offer a great deal of service
during the “lean” hours. It is signifi
cant that these flights are supported and
made possible, to a great extent, by the
higher loads and resultant revenues
earned by the peak-period services.
Travelers want good connections, too.
This is shown by the fact that one-third
of the industry’s business is made up of
on-line and interline connecting pas
sengers. In building up good connecting
services an airline tries to make flights
connect to or from as many other flights
as possible. Obviously, in order to have
a good connection pattern, flights must
be scheduled to arrive and take off
within a given time span.
Providing convenient connections is
the lifeblood of the local service airlines.
Conceived right after World War II,
these carriers link the smaller and inter
mediate cities with trunkline flights to
all U.S.A. and world destinations. Thus,
excellent connections with the larger air
lines at gateway cities is one of the pri
mary services they offer people of their
communities.
Public Service Paradox
Building up excellent connecting pat
terns and scheduling to serve the ma
jority of the traveling public presents
^
.....
I
Preston Wilbourne, Director—Tariffs and Schedules, coordinates all the elements which
determine when and where Piedmont's equipment will operate. Details must be checked
and re-checked, entailing piles of paper work.
J. A. Shulley is the newest member of the
scheduling team. As Assistant Director—
Tariffs and Schedules, he will work with
all phases of timetable planning.
one of the great paradoxes of modern
airline service. While it performs a vital
public service, it creates peak periods
in an airline’s airport station activity.
This imposes heavy demands upon an
airline, for it must “gear up” for full
capacity, even though much of the day
may remain relatively quiet.
An airline must “gear up” inside the
terminal as well, with ticket facilities
and enough Agents equal to the task.
It’s a paradox. In the interest of pru
dent utilization of equipment, facilities,
and personnel, you must avoid peaking.
Yet in the interest of public service, you
must schedule flights when the majority
want to travel, then provide them with
maximum connecting opportunities.
^ Why Schedules Change
Little wonder an airline must publish
new schedules at relatively frequent in
tervals. Obviously it would be a great
advantage to our customers, to our com
pany, and to employees if schedules
could be planned with more lead time
and more stability. But any one of these
factors can easily require a major change
of plans:
* New equipment delivery dates
* Aircraft modification programs
* Changes in maintenance programs
* Government route awards and
route changes
* Schedule action of competitors
* Our own experience with a new
service
* Uncertainty of airport runway,
terminal, or hangar completion
dates
* Switch twice yearly to and from
daylight-saving time
The Public Decides
Another thing: In the final analysis,
isn’t it the traveling public that makes
the big decisions in scheduling? It is the
traveler whose preference decides
whether or not a particular flight has
sales appeal. It is he who won’t wait
for your flight if another airline’s flight
is leaving in 10 minutes. It is he and his
fellows who cause the scheduling “no
man’s land” on the West Coast and the
“bunching” of departures. It is the
traveler who demands good connections
and departures at the “magic hours”—
requirements which cause peaking in
station activity.
Thus the role of management is to
translate public demand into schedules
that can be operated safely and econom
ically. Clearly, it is an art that requires
precision planning, backed up by the
knowledge and judgment gained over
many years of experience.