Knowing flying over the MTOW or out of the CG range can cause an insurance
company to deny a claim.
Continued flight over Max GW can increase the fatigue on an aircraft over
time and increase failures to controls, hinges or wing structures.
Knowingly flying out of CG range, and you are a test pilot.

You mention the Janus with extra weight, our Janus C has a lot of useful
load, max the seats at 110kg each and yes, it can still carry more to reach
Max allowable GW. You mention needing more aft stick to keep the nose up.
Yes, the aircraft will still stall about the same speed, but recovery can be
delayed because more tail force is needed to raise the nose after stalling,
that means more airspeed for recovery to get the elevator to be effective.

You mention loading up "200kg" of water in the wings. Most single seat
gliders are made to carry ballast "up to max GW", to knowingly fly over the
max allowable GW with extra water ballast. Again, you are a test pilot. Not
all gliders can be "filled" as in filling the the water bags to the max
quantity without going over max GW. Each glider is different and should be
checked.



"Bruce Hoult" wrote in message
...
On Mar 18, 2:00 am, toggles mcfarley
wrote:
Hi,
after a hiatus of nearly 20 years I'd like to start soaring again
only this time I'm carrying a few extra pounds. Having decided on this
last year I started working on the weight in Jan and am down to 230lb
in boxers though I am continuing work on it.

It's really not a big deal. Yeah, most gliders have the seats
placarded as 110 kg (242.5 lb), but it's not as hard a limit as some
people like to make out. All gliders are built to take at least 5g of
acceleration at the placarded maximum weights, so they have huge
amounts of reserve strength in normal flying never going above 2 - 3
Gs.

There are a number of things that impose weight limits, but the main
one for the standard 110 kg per-seat limit is that the seat belt
straps and mounting points are rated for a 40g load with a 110 kg
pilot in the event of a crash. If you're a bit over, like me, then try
to keep any crashes down to 35g.

Weight of the non-lifting parts is an important limit. You can
compensate for that one with a light instructor, in which case feel
free to throw the beast around as much as you like. Otherwise go easy
on the aerobatics and fly a bit slower in rough air than the book
says.

The other technical thing to worry about is CofG. Most gliders are
very tolerant of a too-forward C of G. It's pretty common to not be
able to completely trim out the elevator force in a thermalling turn,
even for pilots within the placarded limits, but you'd have to be
grossly out of trim for it not to fly ok. I'm not very proud of this,
but I once forgot to look under the seat for ballast and took off in a
Janus with around 145 - 150 kg in the front seat, between me and the
ballast I didn't notice, and with a reasonably large guy in the back
seat as well. I did notice on liftoff that the stick needed to be
maybe half an inch further back than normal, but it flew just fine
with no problems at all in tight thermalling or in the flare on
landing, and it could still be stalled at right around the normal
speed.

More of a worry, especially with operators in the USA, seems to be
insurance. Some places are absolutely strict about doing everything by
the book. As far as I can tell they are worried about claims being
denied in the event of an accident. Or maybe being sued, I don't
know. Here in NZ a claim could only be denied if exceeding a
particular placarded limit can be shown to have contributed to the
crash, but it may be different elsewhere. Excess weight is of great
concern in powered aircraft as it can easily contribute to failure to
take off in the available space, or failure to get an adequate rate of
climb, but that is far less of an issue in gliders where we regularly
throw 200 kg of ballast in the wings and we're probably only talking
at most 10 or 20 kg extra in a pilot. Maybe it's a different attitude
here but, for example, it is absolutely standard for agricultural
operators to take off at 30% over the manufacturer's MTOW and the
aviation authorities and insurers are happy with it as long as the
excess can be jettisoned in a few seconds.