On Monday, 3 February 2014 23:40:39 UTC, wrote:
On Monday, February 3, 2014 4:55:33 AM UTC-5, waremark wrote:

The 1% altitude difference rule normally requires a maximum altitude difference of 500m or about 1,650 feet for a 50 k silver distance flight. With a position recorder it becomes a maximum altitude loss of 400 m or 1,300 feet.



I heard directly from the SSA about 20 minutes ago that the 100m of altitude "buffer" if you will, only applies to altitude heights.



You can fly your silver distance with one the height differential still cannot be greater than 500m.



Looks like I'm ordering mine shortly........

To be clear, I don't say you should not get one, so long as your eyes are open to the issues of the height buffer and the need for specific software for downloading. But if the SSA say the height buffer does not affect distance claims, that is certainly different from the way the same rules are applied in the UK. It is also illogical. From the BGA website:

"Badge Claims and Position Recorders 24th September 2012

From October 1st, approved GPS position recorders will be allowed for all silver and gold badge legs without the use of an additional barograph. However, where height differences are critical (height claims and claims involving the 1% rule) there will be a 100m penalty applied to the GPS height gain or loss when a position recorder is used without an independent barograph. For example, a silver height gain will need to show a GPS height gain of 1100meters and a silver distance of, say, 60km will need to show a height loss of less than 500m: ((60k*1%)-100)."

You should also consider the implications for any future competition flying.. Again, the height buffer issue may come into play in relation to start and finish heights and penalty zones.

An LX Nav Nano III would clearly be a better device, but for many times the price. A 2nd hand IGC logger might be closer in price, but might be less convenient, for example needing external power or an external aerial.