MotoCalc 8 Release Notes
If you have found a problem with MotoCalc, it may already have been
corrected in a version more recent than the one you have. Before reporting
the problem, please check here if it's already corrected in a newer version.
The most recent version is 8.09.
Click here for information on how to upgrade to
the latest version.
Changes in MotoCalc 8.09
Added PNG support when saving graphs and wiring diagrams.
The MotoWizard now has an outrunner-only option for narrowing down the
choice of motors.
Data files are put into their final location when MotoCalc is first
run, instead of during installation, so that it can be installed by
a user (e.g. the administrator) other than the end user.
Fixed a bug in computing total aircraft weight for multiple ducted
fans, or systems with motors driving more or less than one propeller
Pricing for all orders is now in US dollars.
Support for Windows 10. MotoCalc 8.09 or newer is required to function
correctly on Windows 10.
Changes in MotoCalc 8.08
MotoCalc now stores its files in the system's user data folder,
instead of in the program installation folder. This improves
compatibility with Windows Vista, Windows 7, and Windows 8.
Pricing for orders from outside the USA is now in Canadian dollars.
Changes in MotoCalc 8.07
Fixed a floating point arithmetic error that could occur in rare
cases in the MotoWizard, resulting in a "Floating Point Error"
Changes in MotoCalc 8.06
Fixed a tab order issue on the MotoWizard results page.
Revised the battery temperature computation used on the MotOpinion
page to more realistically deal with parallel cells.
Changed price for Canadian customers to reflect changes in the US/CDN
Changes in MotoCalc 8.05
Added support for Microsoft Windows Vista™. The most significant
change was a switch from the no-longer-supported WinHelp format to
The installation program now gives you the option to put a
MotoCalc icon on the Quick Launch bar.
Fixed a bug that made it impossible to sort a Static Analysis by
number of cells if batteries with paralleled cells were being used.
Changes in MotoCalc 8.04
Improved the MotoWizard's power system selection algorithm, resulting
in much more "mainstream" power system suggestions.
Added support for Lithium-Nano-Phosphate (LiNP) cell chemistry (A123
M1 cells) in the MotoWizard (if requested via the Specific Battery
option on the MotoWizard's Battery page).
The drop-down list of propeller constants (P.Const) in the Drive
System section now includes constants for a wider range of popular
propellers, such as APC-SF, APC-E, and GWS.
When the MotoWizard is busy searching for a power system, you can
now interrupt it if you want to narrow down the search options a bit
more instead of waiting for it to finish.
Fixed a bug in the Airframe section whereby clicking New would result
in MotoCalc assuming a flat plate airfoil by default.
Fixed a typo in the Propeller Constant Estimator window.
Changes in MotoCalc 8.03
Fixed a bug where MotoCalc was computing the efficiency in the
MotOpinion report based on a temperature-compensated armature
resistance even when temperature compensation was turned off. This
resulted in strange efficiency numbers like -5% sometimes.
Changed Weight and Capacity field labels in Battery section to Cell
Weight and Cell Capacity to make it clear that these are per-cell
Increased maximum custom cell voltage to 4.2, and maximum T.Const
and P.Const to 4.0.
Changed remaining occurrences of Idle Current to No-load Current.
Revised tax rates for Canadian customers due to upcoming change in GST.
Included copies of MotoCalc.pdf and
on the MotoCalc CD.
Changes in MotoCalc 8.02
Added support for flat and curved plate wing sections in both the
MotoWizard and the Lift and Drag Coefficient Estimator window.
Reworded full-throttle heat message in MotOpinion.
Fixed a minor bug in the MotoWizard that caused it to rule out certain
set-ups in some cases.
Fixed misaligned column headings in printing of in-flight and static
When updating data from the Internet, MotoCalc will now inform you if
there's a new version of the program available for download.
Changes in MotoCalc 8.01
Added a note to the help for the MotoWizard that clicking Opinion or
In-flight will first copy the proejct to the MotoCalc Workbench.
Updated some topics in the FAQ.
Fixed a minor bug in the MotoWizard where specifying a specific
battery might not find a solution if that battery had too much
capacity for the requested performance and run-time.
Made "Show tip-of-the-day" checkbox label clickable.
Added the word "Clipboard" to the first item in the pop-up menu in the
Report and MotoWizard result windows.
Changes in MotoCalc 8.00
Please refer to the What's New page for the
major new features of MotoCalc 8. The following are additional
minor features and bug fixes made since MotoCalc 7.09.
MotoCalc will generate a warning when you press Compute Report
if you've selected a brushless speed control for use with a brushed motor,
or vice versa.
The MotOpinion report now will warn if full throttle results in an
excessively hot motor even if full throttle is not required for level
MotOpinion will also warn if current exceeds the cells' "C" rating,
The airframe browser now has a Similar button, just like the
motor, cell, and ESC browsers have. This finds airframes that are
aerodynamically similar to the currently selected one (not necessarily
The MotOpinion feature is now available directly from the MotoWizard
and Static Analysis report. In both cases, it gives an opinion on the
highlighted power system set-up.
A section on measuring the constants of brushless motors has been
added to the on-line help.
The Test Data Input window now gives an "Error! Inconsistent Input"
message when it computes something from data that cannot be true.
Fixed a division by zero error that would occur if the wing area
was omitted in the airframe section.
Corrected a problem in the Wiring Wizard where it would sometimes
display too few fuses in a multi-motor, multi-ESC model.
When attempting to add an 11th set-up to the comparison window,
in addition to giving an error message, MotoCalc will open that window
if it isn't already open to give you an opportunity to remove one or more
Output to comma separate value (CSV) files is now padded so that each
line of output (record) has the same number of columns (fields). Some
applications are picky about this when importing CSV files.
Fixed a database indexing problem which prevented MotoCalc from finding
the components of a power system if the component database wasn't currently
sorted by name.
Repaired the data contribution facility so it also works for European
users (or anyone who has their decimal separator set to anything other
Fixed a "date encode error" that sometimes occurred under Windows® XP,
and often occurred when attempting to run MotoCalc under Wine, the Windows®
emulator for Linux (note that MotoCalc is not officially supported on
some people have had success running it under Wine).
MotOpinion did not properly account for the division of current between
multiple ESCs, thus giving erroneous warnings about exceeding the ESCs'
limits. This has been corrected.
Corrected some keyboard shortcuts that had multiple meanings in the
MotoCalc 7 Release Notes
The following are the changes made during the various minor version releases
of MotoCalc 7.
Changes in MotoCalc 7.09
The Prop Constant Estimator window now defaults to metric propeller
pitch and diameter only when the All Metric option is selected in the
Fixed a problem with parallel Lithium-Polymer cells in ducted fan
models. MotoCalc wasn't computing the net battery resistance (and
hence the current) correctly (this was already correct for propeller
Corrected a division by zero fault that could occur if the hands-off
level flight speed exceeded the plane's maximum level flight speed.
The Compare button on a ducted fan static analysis did not work, which
has now been corrected.
Switched to a new installation program because the existing one, which
has worked so well for many years, but has problems on some Windows® XP
systems. The new installer can also put a MotoCalc icon on the
desktop. And, it is 35% smaller, making it faster to download.
Changes in MotoCalc 7.08
Fixed a problem where the wrong contributed items would get imported
if you clicked on the Description or Contributor column headings
before clicking the Add Checked Items to MotoCalc
Corrected an issue with project names containing leading blanks, which
did not appear correctly in the recent projects list in the
Changes in MotoCalc 7.07
Added some smaller Lithium-Polymer cells to those considered by the
Improved the MotoWizard's search algorithm to try power systems with
longer flying times if none were found with the desired flying time.
Fixed a problem that could cause data contribution to fail in some
cases for some users.
Changed the maintenance release upgrade mechanism to use an
installation program and to automatically add all the latest
data to your MotoCalc database.
Changes in MotoCalc 7.06
Fixed a problem that occurs when MotoCalc is running on a computer
that is set to use a comma as the decimal separator (i.e. many
computers in Europe). In some cases, a message about an invalid
numeric value would appear.
Changes in MotoCalc 7.05
The recent MotoWizard change (in version 7.04) to eliminate series
wired brushless motors unfortunately also applied when only a single
motor was specified, effectively eliminating all brushless motor power
systems. This has been fixed.
Fixed a bug where the airspeed at which a stalled propeller becomes
unstalled was computed incorrectly when MotoCalc was set to
operate in Metric.
Changes in MotoCalc 7.04
The MotoWizard can now suggest series/parallel (or parallel/series) wiring
when 4 motors were specified, increasing the number of possibilities for
powering such a model. This wiring arrangement is shown in the MotoWizard
results by an "X" prefix (as opposed to "P" or "S" for parallel or series).
The MotoWizard will no longer suggest series wired brushless motors (since
that is not possible), and when suggesting parallel wired brushless
configurations, will assume a separate speed control for each motor.
Fixed a bug where contribution of speed control data was not working
correctly if intake and/or exhaust diameter and/or length were specified for
a ducted fan.
Fixed a problem where bad data (for example, an unrealistically high motor
resistance) would cause MotoCalc to repeatedly offer to turn off
the filter, even once it was already off.
Clarified the result dialog that is displayed after updating MotoCalc
data from the Internet (or importing from a file). When no new data was added,
it now says so, instead of saying nothing.
Some internal exception handling was added to the MotoWizard to catch
spurious floating point problems that occur when running MotoCalc
on a Macintosh computer using Virtual PC.
Fixed the MotOpinion output to display correctly under Windows® 95.
Changes in MotoCalc 7.03
In the contributed data browser, you can now click on the column
headings to sort by that column (alphabetically by description or
contributor, or by date with the most recent contributions first).
When unable to compute a throttle setting for hands-off level flight,
MotOpinion will use the throttle setting for best lift-to-drag ratio
airspeed. If that cannot be computed either, it will use full
throttle at zero airspeed. In both of the above cases, it will now
issue a detailed warning about the implications of the above.
If the battery temperature in MotOpinion exceeds about 95°C or
200°F, the actual temperature is no longer displayed, since it cannot
be estimated accurately. The message also indicates that proper cooling
may alleviate the problem.
Changes in MotoCalc 7.02
Corrected an error in the temperature component of the air density
correction factor computation. This was accidentally introduced when
the sea-level pressure option was added to MotoCalc 7, and
would result in current predictions a few percent higher than those of
Fixed a problem where clicking in the empty space below the last row
of a static or in-flight analysis would cause duplicate copies of
other (non-blank) rows to appear.
Changes in MotoCalc 7.01
There was a bug in the Contributed Data Browser window. When you
clicked the Add Checked Items to MotoCalc button, the
items in the last tab in which you selected things would not be added,
unless you changed to a different tab first.
Contributing an airframe if you were running in Metric with Prop
Sizes in Inches mode would result in the wingspan not being
converted to inches. Other users downloading that airframe would then
get a wing span 2.54 times larger than it should be. This is now
There were a number problems in the display of various parts of
MotoCalc when Windows® was running in "Large Fonts" mode. These
have been fixed, and MotoCalc works as well in this mode as it
does in the standard "Small Fonts" mode.