On Wed, 05 Dec 2012 07:50:32 -0800, Grider Pirate wrote:

On Dec 5, 7:19Â*am, son_of_flubber wrote:
1.Why do many gliders have two variometers?

Redundancy. I want the audio of an electronic vario, but electronics
work great until they quit, then not at all. A mechanical vario becomes
very handy at that point.

Yes, but be aware that you can get interference between the varios if you
hang a flow type (mechanical) and a pressure sensing (almost all modern
electronic types) vario off the same TE probe. I carry two electronics:
an SDI C4 which runs off the glider's 12 supply and a Borgelt B.40 which
also is normally on the 12v supply but also has a 9v PP3 attached to it -
it can run for over 12 hours on the latter, so is as good at 'get you
home' as a mechanical. Both varios are pressure sensors, so no chance of
interference.

There are other vario types that are designed to run off a 9v battery for
the same reasons, such as the Tasman V.1000 and the Borgelt B.400 which
will run for 7-8 hours off 4 x AA alkaline cells - it replaced the B.40.

2.Assuming for a moment that you are not flying in the flatlands, how
often and under what scenarios do you use your compass? What are some
good exercises for developing airborne compass skills?

Almost never. But almost never isn't the same as never. My compass
'clued me in' when I had rolled out of a very long climb spiral on the
wrong heading. (unfamiliar territory, complete overcast)

Is it a required instrument? It is in some countries.
Mine is tucked away at the bottom of the panel. I get the same
information off my GPS. I used to use a Garmin GPS II+, which is good for
8-12 hours on its internal batteries and now use LK8000 on a Binatone PNA,
which only does 2.5-3 hours on its internal batteries

3.If you needed panel space for a PowerFlarm display, which existing
instrument would you delete (if any)? (Assume a PDA is present.)

No opinion on that one. It would depend on what you had in the panel.

Agreed. I carry a RedBox FLARM which has a 30mm x 60mm display that got
squeezed in without needing to take any instruments out.

Don't forget that you can gain space by swapping 80mm instruments for
75mm equivalents, though at a cost. (cost = replacement instruments +
time & money to replace the panel).


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