My T&T window tilts ok.
When I turn the handle into the turn position the window tilts slightly and the top corner fouls the inside of the window recess preventing it from opening fully.

Voyager, November 2008

malc

I think you may be thinking of a different window type.
This a window 720mm x 1250 mm in a bathroom.
The "hinges" are lever type top and bottom with a moveable lever about 30mm long on the top lever. This lever is approx. in middle of window. When I hold the top of the window in, it moves toward the inside of the window recess as it turns then stops abruptley. At this poin I can't see what is stopping it? I seem to remember on a previous similar window the top middle lever had something to do with it. I have tried to it in several positions this time without success.

Voyager, November 2008

the problem with this type of tilt/turn is that it can go into part tilt before you open therefore you can stop this by placing hand on glass holding firm while you turn handle to open .measure gap between sash and frame rebate it should be 12mm all round it may need sash winding back and up you can do this by removing hinge covers and using allen key to adjust, in the old days they use to use a safety device on side of closing side looked like a sprung butterfly clip this stopped handle being allowed to partially tilt ,only tilt when closed but companies stopped putting them on check if yours has one and its working properly

malc, November 2008

Thanks malc

The window is tilt before turn

Voyager, November 2008

is the window tilt before turn or turn before tilt can advise when we know which way

malc, November 2008