Display
The main, so-called map view of Cumulus consists of three information
areas. These contain:
- the flight information
- a map
- a status bar
In addition, a menu bar may be raised above the display. This gives
access to various setup menus and other options.
Flight information
The group of small windows on the left-hand side are (from top
to bottom and left to right) as follows:
- To - Selected target and, in parentheses, its
elevation. Tap on display to select a target from the Waypoints,
Reachable or Airfields lists.
- Arr - Arrival Altitude above (positive) or below
(negative) the selected target (see glide
path).
- Aircraft symbol - Bearing to target relative to the
current heading. Tapping on the icon will save the current position
as a waypoint, which will show up on the map as a green flag.
- Dis/Eta - Distance to, or estimated time of arrival
at, selected target, respectively. Tap on the display to toggle
between the two.
- Brg - Bearing to target. Tapping on this window causes
the reverse course to be shown with a red flag for five seconds.
- Gs - Current ground speed
- Trk - Track (also indicated by the direction of the
aircraft symbol). If you tap here, the FLARM Radar view is opened.
- Wd/LD - Wind speed and direction toggled with LD by
tapping on the display. The LD display shows both the required and
the current LD to the selected target. See also the LD
description for more info.
- Msl/Std/Agl/Ahl - Current aircraft height in relation
to MSL, standard pressure, ground altitude below the aircraft or
altitude of the home site. To get the dialog box sub-menu for
selecting the height datum, tap on the display.For further
explanations, see Altitude display.
- Var - Variometer display normally derived from the GPS
altitude. If a peripheral device provides variometer information,
this is used instead (see Settings-GPS
help page). Tap on the display to bring up a dialog box where you
can change the integration time and the TEK adjustment.
- Mc - The McCready value used for the glide path and
best speed-to-fly calculations. Tap to open the in-flight dialog for
changing the expected lift, water ballast amount or deterioration in
performance due to bugs. This display is only active if a glider has
been selected. Furthermore the current flight time is displayed, if
the IGC logger is set to the autostart mode.
- S2f/MU - Best airspeed for the current McCready
setting, wing loading and bug setting. This display is only active if
a glider and a target are selected. The target is that displayed in
the To window. Instantaneous variometer information is not
considered at present: it is set to zero.
If you tap on the
window, it toggles the menu bar, placing it along the top of the
display. The letters MU may help you remember this.
Of course all information is displayed in the units you selected in the
Settings/Units dialog.
Map
The map displays a graphical representation of the current position
(indicated by the intersection of the fuselage and wings of the glider
symbol) and heading (indicated by the rotation of the glider symbol).
If there is no GPS fix, Cumulus displays an X symbol instead of a
glider. See under
Manual Navigation for more details.
The current scale is displayed in the lower left corner of the map.
If Cumulus is connected with a Flarm device and the current map
scale is sufficiently low, the most important object reported by Flarm
is also drawn on the map as a circle, labeled with the distance and
the relative vertical separation. In the Flarm display menu a Flarm
contact can be selected; this object will be displayed on the map too,
if it is in view.
The map shows the terrain elevation using colours. The detail level of
this display changes with the zoom factor: more zoom gives more detail
in the terrain shapes. You can turn off the drawing of elevation on
the Settings/Map
Objects page.
Depending on the maps you installed, Cumulus displays airports (the
type is indicated by the standard ICAO symbol), cities (yellow),
highways (red/white), roads (red), railways (dark dashed line) and
water (blue). Not all details are displayed at all zoom factors.
Cumulus also displays airspace structures, the different types being
indicated by different colours configurable under Settings/Airspaces. For
basic information on an airport or airspace structure, simply touch
the related symbol or area on the screen, when the info on the
interesting object will appear in a pop-up window. The window
disappears automatically after a certain time that can be configured
in the Settings/Information
menu.
If you tip longer as one second at the map the airspace
status display is opened as popup window. In the display you can see,
if you are inside of a certain airspace or in its near.
If you touch on an airfield icon, you will get detailed information on
this item. You can add an airfield to your waypoint list if it isn't
in the list already. Added waypoints will have a normal
priority.
Cumulus can calculate which airfields or waypoints are within reach.
These airfields/waypoints have a green background to them. If you
would arrive below the safety height, the point has a magenta
background to it. The line to the currently selected waypoint is
coloured to match, and will be in red if the waypoint is not within
reach. The safety height margin is set at the
Preflight Settings/Common page.
Status bar
The status bar displays the following items (from left to right):
The first item shows the mode Cumulus is operating in. If no GPS
connection has been established (i.e., Cumulus is in Manual mode), G-0
will appear, otherwise G-N, where N is the number of satellites
in use by the GPS receiver.
The next item in the status bar combines a logging and flight
indicator. If IGC logging is enabled and running, the background is
green, whereas if the logger is in standby mode (autostart), the
background is yellow. A grey box means that the logger is not enabled.
The flight status symbol is shown by one of the character symbols
below:
- ? - Unknown
- C - Cruising
- L - Circling Left
- R - Circling Right
- S - Standstill
The next item shows the number of received Flarm devices. If no Flarms
are seen, F-0 will appear, otherwise F-N, where N is the
number of received Flarms. Obviously this item is only visible if
Cumulus is connected to a Flarm device.
The next item in the status bar indicates the current position
in latitude and longitude.
The next item shows the glider selected.
The rest of the status bar is used to display warnings and other
information.
If you want to maximize the screen area for the map display, you can
disable the status bar via the menu entry Toggles/Statusbar.
Altitude display
The altitude display can present the aircraft's altitude relative to
one of four different references. All are derived from the GPS
altitude, unless pressure altitude information is being provided by an
external device.
- Msl - Altitude above mean sea level.
- Std - Altitude based on standard pressure, 1013,25 hPa. This
is used to determine the vertical warning distance to airspaces
defined by flight levels. As Cumulus does not "know" what the current
pressure at sea level is, this must be given as (an area) QNH in
Setup/Pre-flight setup/Common or by using the menu "behind" the
altitude display (described next).
- Agl - Altitude above ground level. Only available when
terrain data have been loaded.
- Ahl - Altitude above home site level. Requires the right
elevation setting of the home site above MSL here.
You can very easily change the altitude display reference: just
tap on the display, and a configuration dialog is opened, where you
can change the altitude reference, the unit, the height correction
factor and the QNH. The height correction factor is used to compensate
the difference between the altitude delivered by the GPS system and
the true altitude. Both GPS and pressure altitudes often differ from
the expected altitude.
Another function of this dialog is the calculation and the display of
the gained altitude. When you press the S button, the
calculation of your gained altitude is started. The AltGain box
shows you the height between your deepest and highest point after the
start button press. That is a good help, if you want to make a certain
altitude gain as it is required for the silver and gold-C and for the
5000m diamond.
Glide path
The glide path indicator gives you an estimate of whether or not your
selected target is in range. This it calculates using the following
parameters:
- your current height
- the elevation and range of the target
- the polar values given in the Settings/Gliders menu.
- the mass of the pilot given in the Preflight Settings
- Glider menu.
- the amount of water ballast carried. The initial amount is
set before take-off in the Preflight Settings
- Glider menu, but if ballast is reduced in flight, then the value
can be adjusted accordingly in the Mc window's sub-menu.
- the reduction in performance by bugs on the wings, also
adjustable in the Mc window's sub-menu
- the wind strength and direction shown in the Wd window
- the minimum arrival height at the target as set in the Preflight
Settings/Common menu.
It is assumed that you fly at the indicated best airspeed, S2f, for the
currently-set McCready value. If, however, the indicator shows a
negative value, you are below the glide path and the target is not
within reach. If you are above the glide path, i.e., the target is
reachable, you can probably fly a bit faster to reach it sooner,
depending on the polar of your glider. The theoretical value of the
speed to fly can be found by adjusting your McCready value in Mc until
the glide-path indicator shows just slightly positive.
LD-Display
In addition to the glide path indicator you can check your situation
with the LD display, too. A precondition for the LD calculation is
likewise that you have selected a target, otherwise nothing is
displayed. The LD display consists of two values, separated by a slash.
On the left side is displayed the required LD to the selected target -
normally this should show positive! The safety height margin and the
elevation of the target are both taken into account in the calculation.
On the right side of the slash is displayed the current LD achieved
over the last 60s. If the current LD is higher than the required LD,
you should be on a safe glide path to your selected target. If you have
climbed or flown at the same altitude in the last 60s, the display
shows a value like
>99. If the calculation result is not sensible, a dash is
shown in the display.