For the USA -- Gliders are aircraft and the IRS says that the
depreciation schedule for an aircraft is 5 years (and only 5 years).

The only way to depreciate it faster is by having your accountant take
advantage of special "bonus depreciations plans" that are sometimes
made available by the government.

If you feel that your glider will depreciate (to a zero value) over a
much longer period than the standard 5 years (as we all know is the
case), it is legal to start with the purchase value and establish a
"risidual value" at the end of the 5 years. The determination of this
residual value is up to you (and your accountant) as long as it is
based on some reality.

for example: $50,000 starting value (purchase price) - $30,000
risidual value = $20,000 in "accounting value" lost in 5 years.

Then your accountant can legally show $20,000 in depriciation over the
first 5 years ($4,000/year). At the beginning of the 6th year you
start over using the $30,000 "balance" as a starting point to reset
the calculation -- all $30,000 over years 6-10 or set up a new
residual value and keep going until all the value is depreciated.

You and your accountant would analyze both scenarios to determine
which method was the most "correct" for your particular glider and
your particular accounting situation. Obviously, your yearly tax
situation will be influenced by the depreciation method you choose.

Steve

Disclaimer -- the above is not accounting or legal advise. You
accountant should be consulted to ensure that your plan of action is
both legal and conforms to the "best accounting practices" that we
should all strive to achieve.