[wkat4242]

I've done gliding and we didn't really do forward slips that much. Perhaps US glider brands are different but all the European (German and Czech) ones I've flown had huge spoilers/airbrakes that were more than sufficient to waste altitude quickly without increasing airspeed.

It's actually a really nice way to land, I wish powered aircraft had this.

[subhro]

Some powered FA aircrafts and pretty much any powered commercial aircraft has air brakes/spoilers.