The Grob G103 is a family of glass-reinforced plastic two-seat sailplanes developed in Germany by Grob Aircraft AG. The aircraft are of T-tail configuration and fitted with upper surface air brakes. They are designed for training, high performance soaring and basic aerobatic flying (Twin II Acro and Twin III Acro).
- Grob G103 Twin Astir Built since 1976, with retractable or fixed undercarriage in front of the center of gravity and water ballast.
- Grob G103a Twin II a new and unrelated design that replaced the Twin Astir from 1980, with fixed undercarriage behind the center of gravity and nose wheel.
- Grob G103c Twin III Replaced the Twin II from 1989, with a new triple-trapezoidal wing, lower control forces and higher airspeed limitations.
![](http://upload.luquay.com/wikipedia/commons/thumb/f/f8/Grob_G103_Twin_Astir%2C_Private_JP7712425.jpg/220px-Grob_G103_Twin_Astir%2C_Private_JP7712425.jpg)
![](http://upload.luquay.com/wikipedia/commons/thumb/b/b0/G103_Twin_II_landing.jpg/220px-G103_Twin_II_landing.jpg)
![](http://upload.luquay.com/wikipedia/commons/thumb/6/6b/Grob_G_103_Twin_III.jpg/220px-Grob_G_103_Twin_III.jpg)