Status US PowerFLARM shipments

Pilots have been flying in Uvalde and feedback is positive, see
postings on R.A.S and other locations e.g. John Cochrane:
http://groups.google.com/group/rec.a...0c70618a?hl=en

Nevertheless there are some issues which require our attention:

FLARM range
Some of the pilots have reported a very short range on the FLARM
transmissions (0.2nm). This is of course too little, as an effective
collision warning requires 1.5nm of minimum range.
Our R&D reacted quickly (not all of Europe is on vacation in August)
and sent out a firmware update which records FLARM range, battery
level, internal temperature and many other parameters into a
diagnostic file.
With the help of some of the affected pilots we were able to acquire
data and defective devices, which have been analyzed.
We have tracked the issue to a batch of defective FLARM RF antennas.
Shipments are on hold while we exchange these antennas, but should
resume after Labor Day.
Existing customers should hold on to their units while we set up a
diagnosis and repair program.

Battery
Runtimes as little as three hours have been reported. This was caused
by the very high temperatures at Uvalde, the PowerFLARM internal
temperature sensor measured up to 160 degree Fahrenheit inside the
housing. Rechargeable Ni-MH batteries deliver less than half their
capacity at those temperatures. Runtimes in 'normal' temperatures have
been confirmed at 6h+

The following recommendations will extend battery life:

1) Reduce Display Brightness
The PowerFLARM LCD display is 'transflective' which means that the
brightness is dominated by how much light falls onto the display. In
fact the brightness setting (of the backlight) makes no difference in
full sunlight.
Reducing the 'Brightness' setting (in Settings/Brightness) can extend
battery life by up to 15%

2) Use alkaline batteries in hot environments
In high temperatures, Alkaline batteries do not degrade as much as the
consumer Ni-MH rechargeables.
High temperature rechargeable batteries are available, we are in the
process of testing.
We will work with dealers and the rental program to make rechargeable
batteries and chargers ? suitable for high temperatures available.

3) Power from aircrafts 12V supply
But make sure no alkaline batteries are inserted when applying
external power!

4) Reduction in power consumption
We will implement firmware improvements which will further reduce the
power consumption of PowerFLARM.


The FLARM Team
August 27, 2011