1.221J/11.527J/ESD.201J – Transportation Systems
Assignment 1- Fall 2004
SMALL AIRCRAFT TRANSPORTATION SYSTEMS
Philippe A. Bonnefoy
INTRODUCTION
with 170,500 registered aircraft in the United
Air transportation systems are based on a
States in 2001. However, compared with the size
variety of vehicles including fixed wing aircraft
of the fleet of major airlines like American
and helicopters. The most diverse and developed
Airlines (over 800 aircraft), the number of jet
category remains the fixed wing aircraft with
aircraft is significant with 7000 aircraft operated
sizes ranging from single seat to 555 seats in the
in the United States in 2001. Turboprops are the
case
least numerous category with 5800 registered
of
the
Airbus
A380.
This
size
characterization relates to passenger vehicles.
aircraft.
However, cargo aircraft have similar range of
aircraft. However, there exists a segment of the
-----------------------------------Piston
170,500
Turboprop
5,800
Jet
7,000
-----------------------------------Total
183,300
------------------------------------
air transportation market that relies on smaller
Table 1: Number of aircraft by type [1].
sizes. The largest fraction of commercial air
transportation is performed using 50 to 300 seat
vehicles.
Modes of Operation
Because
from
an
acquisition
and
OVERVIEW OF CURRENT SMALL
AIRCRAFT TRANSPORTATION SYSTEMS
operating cost perspective, small aircraft are
For the purpose of this study, small
counterparts, the modes of operation are much
much
more
accessible
than
their
larger
more diverse.
aircraft were defined as aircraft able to transport
from 2 passengers, like the Cessna 172 or the
General Aviation
Piper PA28 aircraft up to 12 passengers such as
General aviation is the term used to
Gulfstream V or similar business jets. Of course,
define [2] aircraft operations that encompass all
similar size aircraft used for freight transportation
civil aviation other than scheduled airline flights
are included in the analysis.
and military aviation. It includes everything from
a privately-owned light single-engine aircraft to
business jets, police, pipeline patrol, emergency
Vehicles & Technology
As shown on Table 1, the largest fraction
medical flights, crop-dusting, rotorcraft, sport
of small aircraft is powered by piston engines
ballooning and many other aerial activities. From
an operational perspective, general aviation
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1.221J/11.527J/ESD.201J – Transportation Systems
Assignment 1- Fall 2004
operations can be segregated into three major
professional need. For example, aircraft are
categories. Table 2 shows the utilization of
utilized for aerial observations, tourism like site
aircraft for various type of flying. The activity
seeing, or for critical transportation purposes like
where most of the vehicles are used is the
air medical or air ambulances.
“personal” category. This category is probably
In term of vehicle operation, much of the
the most heterogeneous in term of operations
traffic in general aviation is flown under Visual
since
non
Flight Rules (VFR). However, as this is the case
transportation activity such as leisure flying
for airline traffic, certain part of general aviation,
around an airport, antique aircraft collection to
mostly the commercial part is flown by reference
transportation purposes like private pilots owning
to Instrument Flight Rules (IFR) wherever
their aircraft and using it as a substitute to other
ground facilities adequately support that type of
modes of transportation.
navigation. Basically, the VFR flights require that
-----------------------------------Corporate
11,000
Business
25,200
Personal
148,200
Instructional
14,900
Flight
4,300
Aerial observation
5,100
External load
200
Other work
1,800
Site seeing
900
Air tour
300
Air taxi
3,700
Air medical
900
Other
1,000
-----------------------------------Total
217,500
------------------------------------
good weather conditions exist all along the flight
it
regroups
everything
from
pattern. This makes this type of flying unreliable
from a service perspective. On the other hand,
IFR flights, as performed by corporate and
business aviation, use the same rules and
procedures as commercial airlines. Therefore,
they are not constrained by the weather and
service is more reliable.
Infrastructure
Table 2: Number of aircraft by type of flying [1].
In January 2001, the US airport system
Corporate & Business Aviation is another
was composed of 19306 airports of which 5314
significant mode of operation. In this case,
were public (Figure 1).
aircraft are owned by companies (users) or owned
and managed by charter companies who provide
service to various customers. The largest fraction
of these operations is non-scheduled. However
there exist some scheduled services, mainly in the
case of corporate aviation where a company owns
one or multiple aircraft and uses them to move its
personnel from one company site to another.
Finally, the last category may regroup all
type
of
operations
based
on
a
Figure 1: Current set of airports in the U.S [3].
specific
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1.221J/11.527J/ESD.201J – Transportation Systems
Assignment 1- Fall 2004
The ground facilities needed for most
specific take off field length. Therefore, a large
general aviation flights are generally less
aircraft which requires a long take off field length
sophisticated than those required by the airlines
will be more restricted in term of airport access
operating scheduled flights, but there are many
than a smaller aircraft. For example, single piston
differences between the smaller grass aerodromes
engine aircraft have access to more than 6500
and the airports capable of accepting large
runways in the United States (Figure 2).
corporate aircraft.
Issues
Take-Off Length (ft) (MTOW / Sea Level / ISA+15C)
0
00
16
0
00
15
0
00
14
0
00
13
0
00
12
0
00
11
0
00
10
00
90
00
80
00
70
00
60
00
50
00
40
00
30
00
20
00
10
0
Wide
Body Jet
small
aircraft
There are several barriers that limit the
A 380
B747-400
A310-300
utilization of small aircraft and make it a less
B767-300
B737-800
popular mode of transportation than scheduled
B757-300
Narrow
Body Jet
current
transportation systems
A340-500
A321
A 320
airline services or ground transportation by car,
A319
B737-600
etc.
CRJ900LR
Regional
Jet
about
E195
E145ER/ LR
First, in the case of business and
CRJ200ER
E140LR
corporate aviation, the use of expensive jet
Turbo
Props
Dash 8 Q400
A TR72
aircraft and the low utilization rate of these assets
Beech 1900
Micro
Jets
Dash 8 Q100
impose high costs per mile compared to services
M ust ang
Adam A700
Single
Engine
Piston
Eclipse
offered by scheduled airline. Even though some
Baron58
Piper M alibu
8000
6000
that allow users
1248
5000
to buy a share in a type of
aircraft, lowers the costs, these options of travel
841
4000
3000
209
40
19
16
5
14000-15000
15000-16000
0
149 104
60
13000-14000
146
1000
remain inaccessible to the general public.
384
362
2000
12000-13000
Number of runways at public
airports in the continental U.S.
business models based on fractional ownership,
1763
1593
7000
In the case of personal general aviation,
0
11000-12000
10000-11000
9000-10000
8000-9000
7000-8000
6000-7000
5000-6000
4000-5000
3000-4000
2000-3000
1000-2000
0-1000
pilots using piston engine aircraft have to fly in
good weather conditions unless they have a
Runw ay length ranges (in ft)
Figure 2: Aircraft performance vs. airport
specially equipped aircraft and a special IFR
capabilities in the United States [4] [5].
license. Because of the weather constraint, this
In fact, the ability for an aircraft to use a
mode of transportation is not reliable. In addition,
particular runway is dictated by its take off
small airports that are utilized by general aviation
performance, which is also defined by the take
do not provide the same ground services, such as
off field length. Because this distance is a
car rentals, etc, as the one found at major airports
function of the aircraft weight, and its propulsion
[6]. Therefore, this mode of transportation is less
and aerodynamics capabilities each aircraft has a
attractive.
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1.221J/11.527J/ESD.201J – Transportation Systems
Assignment 1- Fall 2004
Due to high costs, unreliability of service
would have been put in place, the new very light
in some cases, the demand that would exist for
jets, and the current set of more than 5300 un-
small aircraft transportation often find substitute
congested airports in the United States, would
modes of transportation such as scheduled
allow the emergence of new on-demand, point-to-
airlines or cars.
point high speed (Figure 3) and low fare personal
transportation between suburban, rural and
RECENT EVOLUTION IN SMALL
AIRCRAFT TRANSPORTATION SYSTEMS
remote communities.
However, a technological breakthrough
on the vehicle side may allow a wider utilization
of small aircraft as a safe, fast and efficient mode
of transportation.
Breakthrough in vehicle technology
A new technological breakthrough in
small aircraft engines leading to the development
Figure 3: Door to door trip speed for various mode
of more efficient engines will eventually bring on
of transportation (SATS) [7].
the market new four to six seat aircraft, for half
the price of current similar jets and with
Limitation of the SATS program
significantly lower operating costs. As of 2004, at
However, the SATS program remains a
least 6 manufacturers are in the process of
concept of operation and there exist several
bringing aircraft to certification, among them
limitations to this concept in the current air
Eclipse, Adam aircraft, Cessna, etc.
transportation environment.
The failure of Williams International, the
Long term vision: “The SATS Program”
engine manufacturer that started the development
In the 1990s, as the new engine
of the efficient small jet engines (EJ22), to
technology was starting to be developed, NASA
deliver the announced performance constitutes a
saw in this emerging technology a way to
first limitation. Other engines for small aircraft
develop personal air transportation. The program
such as Pratt & Whitney PW610 and PW615, the
called “Small Aircraft Transportation System
Williams FJ33 will become available eventually
(SATS)” [6] was lead by NASA Langley. The
if they are certified; the performance levels are
goal was to test an innovative concept for
not as revolutionary as the one the EJ22 would
personal air transportation, as well as developing
have offered. Engine lower performance means
key technologies that would be required to
higher operating costs and therefore makes the
achieve such goal. Once these technologies
operation of the aircraft slightly less attractive.
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1.221J/11.527J/ESD.201J – Transportation Systems
Assignment 1- Fall 2004
The currently long certification process
services for significantly lower fares than current
required for aircraft certification make it costly
business and corporate aviation. The air taxi
for manufacturers to quickly develop new aircraft
based concept solves the limitations of the SATS
pushing the innovation and evolution process fast
program that have been illustrated earlier. In fact,
as it is the case, for example, in the automobile
the higher utilization of the aircraft implies lower
industry.
unit costs. The safety and training issue is solved
Another limitation remains the level of
by flying the aircraft with two professionally
training required from a pilot that would own and
trained pilots, etc.
operate its aircraft for personal transportation.
Unlike current piston engine aircraft, very light
CONCLUSION
jets are faster and fly higher which require more
Starting from the current state of the
training and experience to fly. This training issue
small aircraft transportation system, this paper
of private pilot willing to fly very light jets comes
has addressed the current limitations of this
with insurance issues where insurances are
transportation
expensive and require pilots to go through special
evolutions of the system enabled by emerging
training courses.
technologies were analyzed and limitations for
From a cost perspective, the acquisition
short
to
system.
medium
term
In
addition,
development
future
were
and operating cost requires the aircraft to be
addressed. Finally, a business and operational
operated several hundred hours per year to justify
model that might be the first step towards a more
such costs.
accessible, reliable and efficient small aircraft
These are several barriers that make the
transportation system was presented.
concept difficult to implement on a wide scale, at
least in the short term.
REFERENCES
Near term models: Air Taxi
[1]
United
States
Department
of
Transportation,
Federal
Aviation
Administration
[US
DOT
FAA]
Factbook of 2001, 2001
[2]
Definition from Wikipedia, [online
encyclopedia]
http://en.wikipedia.org/wiki/General_avi
ation [last accessed 14/SEP/04]
[3]
Personal plot, data source: FAA,
National Plan for Integrated Airport
System, 2002.
Jane’s All the World Aircraft, 2004-2005
However, on-demand point-to-point air
transportation may not be accessible, in the short
and medium term, to masses of individual
owning their plane and using it as conveniently as
their car, similar services might be available in
the upcoming years. The solution would come
from aviation companies, who would own and
operate large fleets of these small aircraft and
[4]
offer on-demand point-to-point air transportation
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1.221J/11.527J/ESD.201J – Transportation Systems
Assignment 1- Fall 2004
[5]
FAA, Airport Form 5010 data, [online
database],
URL:
http://www.gcr1.com/5010web/ [last
accessed September 2004]
[6]
DOWNEN Troy D. and HANSMAN R.
John Jr., Analysis of Barriers to the
Utility of General Aviation based on
User Survey and Mode Choice Model,
Report No ICAT 2002-01, MIT, 2002.
[7]
NASA, SATS program website, URL:
http://sats.nasa.gov/
Other references on the subject:
BOKULICH Frank, The world of business jet
technology,
Aerospace
Engineering,
SAE
Aerospace Publications, p23-27, April 2002.
COSTA
Peter
R.,
HARNED
Doug
S.,
LUNDQUIST Jerrold T., Rethinking the aviation
industry, The McKinsey Quarterly, Number 2
Risk and resilience, 2002.
FALLOWS James M., Free Flight: from airline
age to new age of travel, Publics Affairs,2001.
PORT Otis, Many Are Hailing This Air Taxi,
BusinessWeek Online, August 28, 2002.
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