On Feb 18, 10:25*am, Greg Arnold wrote:
*However, sometimes the
airworthiness document requires one. *See, for example, the type
certificate data sheet for the ASW-27 athttp://tinyurl.com/2qpqhr.

Interestingly the ASW-28 TCDS issued later does not list a compass in
the equipment list.

For an experimental glider, even if here is a standard type
certificate and associated TCDS, I don't think the TCDS applies.
Minimum equipment may be listed in the experimental certification docs
(operational limitations) but that may depend the date of the
airworthiness inspection and the region in which it was conducted.
Recent experimental glider cert docs seem to be more standardized than
they were when the ASW-20 was new.

Andy