Rory O'Conor wrote:

Apart from initial cost and traditionalism - "gliders dont have engines", I
cannot
understand why so few people have SLMG.

I suspect that Eric's earlier response, about the higher capital cost
of a SLSP or MG is the main reason there aren't more of them. I know
several people who flew pure gliders until they could afford a MG or
SLSP.

But, in addition to the capital cost, there's also the higher ongoing
maintenance cost -- both in $ and time. I sometimes joke that a motor
glider has 10x the maintenance of a pure glider, but is 10x more
useful.

While the actual numbers depend on the specific ship and are hard to
pin down, in reality, for me, I suspect the maintenance increase is
more like a factor of 2-4, not 10, but the utility factor increase is
well over 10 times. So, for me, the extra work is well worth it. But,
for someone else with different constraints and options, adding a
motor might not be worth the trouble. What are some of the factors
that make a SLSP/MG more or less useful?

1. Whether you live near good soaring. I live in the SF Bay Area, with
minimal local soaring. If I lived in Minden, the value of an engine
would be smaller. With a MG, it's a lot closer to living in Minden. I
can fly there in 1.5 hours, so I've done a number of 1 day soaring
trips, launching about noon, returning about 6 PM, with three hours of
great soaring in the middle. A weekend is even better, but would be
minimal if I had a 5 hour drive to Minden, and then back again.

2. Distance to a gliderport vs. an airport that can handle a MG.

3. Whether you are willing to do cross country soaring without an
engine. For the year that I flew pure gliders, I never strayed out of
gliding distance of the glider port -- tho at Minden that could mean
quite some distance on a good day. I wasn't willing to take the chance
of having to land out, and be stuck til an aero retrieve or trailer
could fetch me, possibly not until the next day. I had always intended
moving quickly to a MG so I could do cross country soaring with less
uncertainty as to my return time.

4. Taste. Some people like me will love the freedom of an engine being
there. Others will scoff at the lack of purity. Neither is right or
wrong. Just different tastes. And tastes change with time, so the guy
who was a purist in his 20's might opt for an engine in his 50's --
when he's also more likely to be able to afford it.

Martin