FOR 2005, PORSCHE
THE TECHNOLOGY ENVELOPE
Sports Chrono Package
Plus lets the 911 driver dial in preferred performance parameters
For Porsche, the ultimate challenge is always to push the
limits of possibility. From the company's very beginning, Porsche has
explored and expanded the limits of performance, through competition on the
racetrack and with innovative technology engineered to enhance the driver's
daily experience on the road.
Throughout its proud history, Porsche has been
respected for the dynamic quality of its vehicles and for the engineering
expertise and technological innovations that make those vehicles so safe, so
secure and, yes, so exciting to drive. Now, for the 2005 model year, an
already impressive list of engineering innovations expands with the
introduction of the Sports Chrono Package Plus.
Porsche Active Suspension Management for the 911
There are two versions of Porsche Active Suspension
Management, one for the Cayenne sport utility vehicle and the other for the
2005 Porsche 911 Carrera and 2005 Porsche 911 Carrera S.
For 2005, Porsche Active Suspension Management is standard
equipment on the 911 Carrera S and optional on the 911 Carrera and uses
active damper technology to provide both a comfortable yet sporty suspension
setup for regular driving and very aggressive settings for performance
Compared with the standard suspension, PASM lowers the entire
car by 0.39 inches (10 mm). Further, by pressing a button on the center
console, the driver can chose between normal and sport settings.
The normal setting provides a more comfortable damper setting
that changes gradually to a sporting mode as the driver adopts a more
dynamic style of driving. For example, when cruising down the freeway, the
normal setup absorbs minor and medium bumps more smoothly than the standard
On the other hand, the sport mode activates a firmer damper
control map for agile, dynamic driving styles and minimizes body roll to the
point that lap times in testing on Germany's famed Nuburgring racing circuit
were reduced an average of five seconds per lap compared to the standard 911
Porsche Active Suspension Management for the 911 links
adaptive dampers and a pair of accelerometers that track vertical movements
of the body with a control unit. Active dampers have a similar structure as
standard shock absorbers, but also have a bypass valve in addition to the
regular opening in the main piston so oil flow can be increased or reduced
as needed to infinitely adjust damping forces. In the event of a system
failure, the valve closes automatically and PASM maintains its hardest
position to provide the safest dynamic driving mode.
One accelerometer is mounted on the top of the right front
damper dome and the other on top of the left rear dome. The control unit
compares reading from these accelerometers with lateral acceleration,
steering angle, road speed, brake pressure and engine torque to determine
optimum damper control for each wheel.
PASM has five specially developed software modules to assure
excellent performance in all driving conditions:
change module responds to fast movements of the steering wheel and
instantaneously increases damper forces on both axles to better control
lateral forces and improve handling in extreme dynamic situations.
control module does two things: in the normal setting, it increases damper
forces whenever vertical movement of the car's body exceeds a certain
threshold, for example, on a bumpy road; in the sports mode, the system
slightly reduces the damping effect to maintain better wheel contact to
prevent the car from 'jumping' around while assuring good ride comfort.
acceleration module increases damping effect through a turn as a function of
road speed and lateral acceleration to enhance driving precision.
module responds as soon as the driver starts to apply the brakes and
switches to a harder damping effect to reduce body 'dive' to assure faster
transmission of braking forces to the road to optimize braking performance.
Then, during brake application, the system switches to a softer control
setting after a certain period, applying different forces to the front and
rear axles as needed. This is particularly effective on bumpy roads, where
it assures better surface contract and shorter stopping distances.
change module switches damper control maps and establishes different damping
forces on the front and rear axles in all-out acceleration, when the driver
lifts off the accelerator or shifts gears. This prevents the car from
developing too much 'squat' in normal driving. In the sport setting, the
system briefly switches to a softer damper response to improve traction when
accelerating on a bumpy road.
Sports Chrono Package Plus: Much more than a stopwatch, it sets higher
A clock-style gauge mounted on top of the dashboard of the
2005 Porsche 911 Carrera or 2005 Porsche
911 Carrera S signals that this car is equipped with Porsche's newest
technological innovation: the Sports Chrono Package Plus.
While there are several sports cars available with a built-in
stopwatch, Porsche's Sports Chrono Package Plus does much more than record
sprint or lap times. Of course, Porsche's Sport Chrono Package Plus does
include a stopwatch and lap-counting function, and uses the Porsche
Communication Management (PCM) system to provide graphic display
of such information. But Porsche's Sports Chrono Package Plus also allows
the driver to engage more aggressively set electronic control maps for the
Motronic engine management system, for the Porsche Stability Management (PSM),
for the Porsche Active Suspension Management (PASM) and for the Tiptronic
S transmission (on vehicles equipped with these options).
By pressing a button on the center console, the driver
engages Sports Chrono Package Plus to take driving dynamics to a standard
never before available. Under Sports Chrono Package Plus, changes are
effected to the gas pedal control lines, engine speed limiter, engine
throttle butterfly, PSM, PASM and Tiptronic S.
When the Sports telltale lights up on the center portion of
the gauge cluster, the driver knows that the E-gas control line has switched
to a steeper configuration that puts the Tiptronic S in its manual mode,
thus the throttle butterfly responds more quickly to movements of the gas
pedal and the driver enjoys even more spontaneous response from the engine.
Should the driver keep the accelerator pedal fully depressed without
shifting gears, the engine speed limiter in gears 1-5 intervenes far more
abruptly than in routine driving. Shifts become less oriented to comfort
and the throttle butterfly closes faster when the driver lifts off the
accelerator pedal, thus providing a more dynamic driving experience, more
similar to the feedback a racer gets from a car on the track.
The operation and intervention of PSM also changes to provide
greater agility. For example, when accelerating out of turn in the Sports
mode, higher anti-spin control thresholds allow more slip from the rear
wheels. This can result in even faster acceleration because PSM does not
intervene as quickly. Likewise, other PSM thresholds, such as those that
control the anti-lock braking system, also are raised to a level that allows
more dynamic control by the driver before the system intervenes. And the
particularly skilled driver retains the option of switching off the PSM
system and taking manual control of the car's dynamic direction.
Under the Sports Chrono Package Plus, the PASM also switches
automatically when needed to a sports program that provides firmer
suspension settings, reducing even further body lean through corners and
enhancing contact between the tires and the road surface. However, there
are circumstances, such as on wet or snowy roads, in which an aggressive
driver knows that a 'softer' suspension setting can enhance traction and
thus the PASM button can be pushed to put the car in its normal setting even
when the sports mode is active.
So the driver can graphically verify the improved dynamics of
the 2005 Porsche 911 Carrera and 2005 Porsche 911 Carrera S equipped with
Sports Chrono Package Plus, the driver can push a stalk attached to the left
side of the steering column to record various route segment times, which can
be reviewed graphically on the PCM screen.
The Sports Chrono Package Plus is just the latest in a long
list of Porsche technological innovations available on 2005 models of the
911, Turbo or Cayenne sport utility vehicle. Information on
other technologies follows:
PASM for the Cayenne SUV
Porsche Active Suspension Management (PASM), a variable
damping system, is standard equipment on the Porsche Cayenne Turbo and is
optional on the Cayenne S and Cayenne.
On the Cayenne, PASM incorporates an air suspension system
that provides extra ground clearance in rough terrain, automatically lowers
the vehicle at highway speeds, and has a self-leveling feature that helps to
provide a proper position regardless of passenger or cargo loads or the
presence of a trailer. The air suspension incorporates six ride height
levels, allowing a range of 4.56 inches.
adjusts damper forces in response to road surface conditions and each
driver's style. For example, under the rapid and powerful application of the
gas and/or brake pedal, as when driving aggressively on twisting roads, or
when driving with cautious movements on particularly rough terrain, PASM
steadies body sway and dive motions by monitoring body movement through five
accelerometers. As soon as the motion of the Cayenne's body exceeds
programmed limits, PASM intervenes and works to stabilize the vehicle by
acting on specific dampers
PASM also allows the Cayenne driver to select from Comfort,
Normal or Sport modes. However, should a driver select, say, the Comfort
mode but then operate the vehicle in a more sporting style, the system
automatically switches to the Sport mode and makes the appropriate changes
in damper settings.
Porsche cautions drivers that while PASM
provides for extremely dynamic handling, no system can overcome the laws of
Porsche Stability Management
Porsche Stability Management (PSM) helps keep a vehicle going
in the direction the driver steers, whether on a dry paved road, a slippery
road or even unpaved surface. PSM uses data from several sensor inputs to
detect a loss of grip. The system reduces instability by applying brakes to
individual wheels and, if necessary, by reducing engine power. PSM operates
so quickly that most drivers will not notice its corrections.
PSM is tuned to the driving style and skills of Porsche
drivers. Drivers who want total control of their vehicle can disengage PSM
with a switch located on the dashboard. However, for purposes of safety,
PSM automatically engages under braking and then disengages when the driver
lifts off the brake. Porsche also cautions drivers that while the system
provides a dynamic handling aid, no system can overcome the laws of physics.
With the introduction of the 2005 Porsche 911 Carrera and
2005 Porsche 911 Carrera S, a newest generation of PSM uses new anti-lock
brake sensors that take their readings not from conventional wheel pulses
but from multi-pole seats fitted directly on the wheel bearings. These
improved signals allow more precise processing and control. Instead of
conventional shaft valves, linear solenoid valves adjust brake pressure with
nearly infinite precision.
To provide pressure more quickly, a new hydraulic pump is
used and a pre-charging pump and its connections are eliminated, reducing
system weight by 25 percent, or 6.6 pound (3 kg).
Another enhancement to PSM for 2005 gives the
enthusiast driver more control over the system. As in previous years, PSM
can be turned off through a switch on the dashboard but now PSM does not
automatically reactivate when the brake pedal is depressed. Instead, the
system reactivates only when the pedal is pushed hard enough to exceed the
ABS control threshold on at least one front wheel. This change allows the
enthusiast driver more dynamic freedom, including slight use of the brakes
Porsche Traction Management
Drivers might think that the laws of physics do not apply to
Porsche Traction Management (PTM), the newest generation in four-wheel drive
technology that comes standard on every Cayenne. PTM significantly
influences the Cayenne's dynamic performance by coordinating the vehicle's
outstanding power and torque, its sporty and agile handling, and its
excellent driving dynamics with superior performance off the beaten track.
In normal conditions, PTM feeds 62 percent of the engine's
power to the rear wheels and 38 percent to the front wheels. This assures
that the Cayenne has the same basic dynamic characteristics as the Porsche
911. However, through the use of a multiple-plate clutch, the Cayenne can
vary the power split as needed, if necessary feeding 100 percent of the
engine's torque to the front or rear wheels.
The map-controlled front-to-rear lock and the optional rear
axle differential lock not only respond to lack of traction on the front or
rear wheels, but incorporate sensors to measure such things as vehicle
speed, lateral acceleration, steering wheel angle and operation of the gas
pedal. PTM determines the optimum lock on both axles and distributes drive
power as actually required to the front and rear wheels.
Thus PTM acts as an intelligently networked electronic system
that helps to provide stability and safe lane change behavior both at high
speeds and when driving on snow and ice at moderate speeds.
This innovation offers an impressive range of outstanding
driving stability and traction in all situations, regardless of the
steering provided by the front-to-rear differential lock opening up to avoid
any understeer effect;
front-to-rear differential that ensures better control when driving to the
directional stability and better road grip by operating the front-to-rear
lock as required;
traction by increasing locking action before the wheels start to spin.
Porsche Stability Management (PSM) remains consistently in
touch with Porsche Traction Management (PTM), but intervenes only when the
vehicle reaches its limits.
Masterminding essential systems such as ABS (Anti-lock
Braking System), ASR (Automatic Slip Regulation) and ABD (Automatic Brake
Differential), PSM cuts in immediately under critical over- or understeer
conditions and tells PTM to open the locks to restabilize the vehicle by
applying the brakes specifically on individual wheels.
The Cayenne successfully combines outstanding performance on
the road with equally outstanding off-pavement abilities. Indeed, it is
already a genuine master off the beaten track in its 'basic' configuration,
intelligent four-wheel drive enabling the Cayenne to easily cross light
terrain without any adjustment of the traction systems.
On rough terrain, the Porsche Traction System uses the
reduced-ratio gearbox featured as standard equipment. With its reduction
ratio of 2.7:1, the reduction gearbox is ideal for even the most extreme
off-pavement maneuvers, easily handling steep gradients and, in particular,
Activating the low-range mode by means of a toggle switch on
the center console, the driver can automatically prepare several control
systems for off-pavement driving conditions: PTM switches over to the
reduced ratio for off-pavement requirements and changes to a special
off-pavement control map activating the differential locks, PSM responds by
setting ABS and ABD to a special traction mode for off-pavement motoring,
and the air suspension featured as standard in the Cayenne Turbo
automatically lifts the entire vehicle up to its off-pavement level.
Porsche is the first carmaker to offer this
combination of systems all controlled by one central off-pavement switch and
thus significantly facilitating operation of these systems when driving
under extreme conditions.
Porsche Side Impact Protection
POSIP (POrsche Side Impact Protection) is standard on all
Porsches and provides the driver and front passenger with a broader scope of
protection than conventional side airbags.
A special feature of POSIP is that this airbag system is able
to ensure exemplary protection, even in an open convertible.
Housed in the door panel of Porsche sports cars, the airbag
modules differ from conventional units through their large volume and airbag
geometry. In a collision from the side, this ensures not only the usual
protection of the torso, but also helps to protects the driver's and front
passenger's head from hitting an obstacle at the side, regardless of the
fore-and-aft position of the seats.
Because of the size of its interior, the Porsche Cayenne
sport utility vehicle gets a special airbag system that includes front, side
and head curtain airbags. In the Cayenne, 911 Carrera and Carrera S the
side airbags have been placed in the backrests of the front seats. While
providing protection for the driver and front-seat passenger's heads, this
separate airbag also helps to protects passengers sitting in the rear seat
in the event of a side impact. This system is designed to provide
protection even when a narrow obstacle, such as a pole or a tree, strikes
Variable-ratio rack-and-pinion steering
For the first time, the 2005 Porsche 911 Carrera and 2005
Porsche 911 Carrera S feature standard variable-ratio steering, a system
that enhances the car's agility on winding roads while retaining exceptional
stability at higher speeds.
When the steering wheel is turned 30 degrees from its
centered position, the steering ratio remains similar to that on the
previous generation 911. This assures a smooth and calm driving experience,
even on rough surfaces on which a driver might have a tendency to steer too
However, when the steering wheel angle exceeds
30 degrees the steering ratio becomes more direct, reducing the lock-to-lock
ratio from its usual 2.98 to only 2.62. This gives the driver better
control both on fast, winding roads and in slow-speed parking maneuvers.
Porsche Ceramic Composite Brakes
Because of their exceptional performance in extreme
conditions, ceramic composite brakes were developed for use in high-level
motorsports competition. Porsche was the first automaker to apply them for
road use, with Porsche Ceramic Composite Brakes (PCCB) included
as standard equipment in the 2005 Carrera GT and the 2005 Porsche 911 Turbo
S coupe and convertible.
Ceramic composite brake discs provide a 50-percent weight
savings compared to conventional metal discs. This reduces unsprung weight,
enhances shock absorber response and vehicle handling, and also improves
fuel efficiency and thus contributes to reduced emissions.
Ceramic composite brake discs have an extremely hard surface
that provides consistent frictional values throughout the deceleration
process, even in braking from extremely high speeds and at high operating
temperatures, such as those generated from repeated braking. But the system
also provides benefits in low-speed situations. In the event of an
emergency stop, PCCB technology does not require heavy pedal forces or
outside technological boosting assistance to achieve maximum and immediate
With cross-drilled discs and pads that are resistant to water
absorption, the ceramic composite brakes provide superior response in wet
conditions as well as dry.
Because of their hard surface and immunity to
salt corrosion, Porsche Ceramic Composite Brakes have an extremely long
Porsche Ceramic Composite Clutch
With the introduction of the Carrera GT, Porsche launched the
Porsche Ceramic Composite Clutch (PCCC). Ceramic composite
clutches were developed for use in motorsports at the highest levels of
international competition. However, in such applications and for specific
use on the racetrack, they often have short lives.
But by applying lessons learned through the development of
Porsche Ceramic Composite Brakes, Porsche has created a new clutch design
and configuration that applies ceramic composite technology to the public
roads with a two-plate dry clutch made from a composite of carbon fiber and
silicon carbide. This ceramic composite clutch is compact and light, but
also strong and has an exceptional service life.
In the Porsche Ceramic Composite Clutch, the plates are only
6.65 inches (169 mm) in diameter, less than half the size of typical
production car clutch plates, which can run as large as 15 inches (380 mm).
Because it is extremely compact and
lightweight, the PCCC contributes to the Carrera GT's incredibly low center
of gravity. The PCCC's low mass also has a very positive effect on the
dynamics of the Carrera GT's 605-horsepower (SAE), 5.5-liter V10 engine and
its six-speed, transversely mounted transmission.
Tiptronic S transmission
Tiptronic S is
Porsche's version of an automatic transmission, and offers five forward
gears for the 911 models and six for the Cayennes. The driver can shift
gears manually by tipping the selector lever on the center console or by
using toggle-style switches on the steering wheel. The driver presses the
upper portion of the thumb switch or tips the center console shift selector
forward to advance the gears, or presses the lower part of the thumb switch
or tips the shift selector back to downshift.
One major advantage of the Tiptronic S is that it provides
the driver with the option of intervening while the transmission is in
automatic mode. The driver can move the thumb switch on the steering wheel
and shift gears manually even though the gearshift selector lever in the
center console remains in the automatic position. In such a case, the
manual mode is activated for at least eight seconds, and this period is
extended when the car is in 'overrun' - for example, on a downhill grade, to
capitalize on engine braking - or when the driver downshifts before the
entrance to a curve and the car is under lateral acceleration as it
negotiates the turn.
When in such a situation, the letter 'M' appears in the
right-hand instrument dial and the specific gear currently engaged also is
displayed. At the same time, the transmission retains its kick down
function so the driver can downshift again as needed. The transmission can
downshift by as many as three gears when the driver steps hard and quickly
on the gas pedal.
In automatic mode, Tiptronic S adjusts to various shift
control maps based on the driver's style of driving and the route. The
range of shift points extends from a particularly economic mode activated
whenever the driver prefers a calmer and more reserved style of driving
(with the gears shifting up at an earlier point and engine speeds being
reduced accordingly) all the way to a very dynamic, active mode (with the
gears remaining in mesh for as long as possible when accelerating, using the
engine's free-revving driving characteristics). The crucial factor in all
cases is the driver's foot on the accelerator: Moving the gas pedal quickly
and dynamically, accelerating frequently with full power, the gearshift
points change accordingly, switching if necessary to the most dynamic
variant and vice versa.
Over and above its ability to recognize the driver's style,
Porsche Tiptronic S also features:
program that prevents the transmission from shifting up too soon, thus
increasing the temperature of the catalytic converter as quickly as possible
while allowing the engine to warm up smoothly and without any strain;
gearshift that immediately moves the shift points to the most sporting and
dynamic program whenever the driver presses the gas pedal quickly and
of upward gearshift in overrun when the driver's foot suddenly lifts off the
accelerator, for example, before entering a bend;
to the next lower gear to optimize engine braking when the brakes are
upshift that delays shifting into a higher gear after an active downshift;
gears in a bend to prevent upshift; and
recognition that retains lower gears as long as possible in uphill or
To reduce the possibility of an improper shift when the
Cayenne SUV is traversing rough terrain, the steering wheel switches are
deactivated when the reduction gearbox is engaged. In this case, the driver
can shift manually only by moving the shift lever on the center console.
But the driver may not have to shift manually because Tiptronic uses
gearshift control maps to ensure optimum power in rough terrain.
Another Tiptronic S feature in the Cayenne is a
hill-holder function that prevents the car from rolling backward when
setting off in a forward gear, even on a steep grade.
VarioCam variable valve timing
VarioCam and VarioCam Plus are Porsche's patented variable
valve timing and valve lift technologies. Originally developed for the
Porsche 911 Turbo, they are designed to optimize each vehicle's dynamic
capabilities while properly managing the fuel consumption and exhaust
emissions of such high-performance engines.
Similar technology can be found in every Porsche engine.
VarioCam refers to cam timing adjustment that can be either a
one-step system, as on the Porsche 911 Turbo, or a fully adjustable vane
cell system, as on the 911 Carrera models and the Cayenne models. VarioCam
Plus adds valve lift control and is used on vehicles such as the Porsche 911
VarioCam technology allows adjustment of the camshaft angle
and is set to provide optimum performance for each Porsche engine. For
example, in the Cayenne S and Cayenne Turbo, an adjustment of up to 25
degrees assures a beefy torque curve for the sport utility's V8 engine.
With VarioCam, intake camshaft timing is fully variable
through a wing-cell adjuster fit directly on the camshaft drive sprocket.
Oil pressure is used to turn the position of the inner wing-adjuster wheel
versus the outer sprocket. Because the intake and exhaust camshafts are
driven directly via a roller chain, this system makes the conventional
three-stage chain drive redundant between the crankshaft and the camshaft.
Porsche's patented VarioCam responds quickly to any sudden
need for power or, conversely, to a more reserved style of driving, say in
city traffic. This is possible because of the way it makes precise
adjustments to valve opening and closing times.
When running under part load, the intake camshaft is set to
an earlier opening point. The residual gas remaining in the combustion
chamber builds up maximum output through the small overlap in the opening
and closing times. Maximum torque is provided by extended valve overlap and
the earlier conclusion of the intake period.
VarioCam Plus not only adjusts camshaft position to provide
continuously adjustable valve timing, but also varies valve lift and
duration. This helps to flatten as well as smooth the torque curve while
reducing emissions. The use of dual valve springs ensures reliable
Some have said that driving a Porsche equipped with VarioCam
Plus technology is like having two engines in one vehicle: an engine that
provides maximum horsepower and torque and another that provides quiet and
However, Porsche technology combines these characteristics
into each engine. Even under cold starting, VarioCam Plus improves the
engine's characteristics by reducing emissions through suitable adjustment
while the engine warms up.
While the engine is at idle, the small cams control valve
lift and valve timing is optimized to keep any valve overlap to a minimum.
The small valve lift serves to reduce friction and, thanks to the very short
opening times, it significantly increases the charge motion while reducing
emissions from any previous combustion within the chambers. The system also
reduces fuel consumption and emissions by as much as 10 percent.
Under part load, valve lift shifts to a large overlap and the
engine runs with internal recirculation of exhaust gases to minimize any
throttle effect and to reduce fuel consumption.
Under full load, maximum torque and horsepower are ensured by
a highly efficient gas charge cycle with minimum losses as well as an
uncompromising cam contour and suitable adjustment of valve opening and
The system is controlled by engine management
software, Motronic ME7.8 for the Carrera models and MY7.1.1 for Cayenne
models, designed specifically for Porsche's requirements. Engine speed, gas
pedal position, engine oil and coolant temperature and even gear selection
are monitored. The driver's commands for horsepower and torque are compared
with control maps. Within milliseconds, the computerized system responds and
makes the proper adjustments.
Porsche Communication Management
Porsche Communication Management (PCM) operates
at the speed of light.
Using Porsche's MOST (Media-Oriented Systems Transport)
technology, PCM uses light wave conductors to exchange multi-media data in
every Porsche model in which it is installed. The big advantage of this
technology is that it exchanges data without any loss of quality and at
extremely high speeds. Among other features, this assures high-quality
audio transmission for radio, CD changer and amplifier units.
Featuring a double audio tuner, CD player and trip computer,
optional PCM provides a user-friendly design that includes a color screen
and 12-digit keyboard. In the Cayenne, that screen is 6.5-inches across and
provides the clarity of a 16:9 aspect ratio. The keyboard can be used for
entering information such as radio station frequencies.
In addition, buttons beneath the display provide direct
access to the individual menus such as trip computer (Trip button) or the
navigation system (Navi button). Two buttons providing direct access to the
Set (Set button) and Return (button with a bent arrow), thus avoiding the
need to 'jump around' from one sub-menu to another and wasting a lot of time
in the process.
As well as improved radio reception, ensured by a modern
double tuner consistently looking for the best frequency, the navigation
module features the following outstanding highlights:
of various navigation functions: Functions can also be presented on the map
in the display, informing the driver of such facilities as restaurants,
service stations or parking lots;
road junction zoom: This function automatically enlarges road junctions in
the active guidance mode, providing helpful support above all at dangerous
points where a road junction is unclear.
Benefiting from the wider range of map options, the user is able to shift
the map display, scroll and position the map as required. This enhances
navigation from the current location to the desired destination, checking
out and memorizing a destination by means of a reticule display without
having to enter the exact address.
planning: The tour planning function allows the user to enter and memorize
routes with as many as eight destinations in a row. When setting out, the
system will automatically guide the driver to the individual destinations on
the way, in precisely the order recorded in advance. Further processing
options on such extended routes are also possible, such as adding
information, removing destinations, changing the order of destinations on
the way or skipping a certain point;