It would be difficult to stay stable for any length of time because those basic instruments give you almost no information on your angle of bank.

If you could manage to keep you spirit compass on a constant heading and keep the yarn straight, your wings would be level.

So while it would be possible, I would think you would need an experienced glider pilot and relatively calm conditions to maintain wings level for any usable length of time.

It would be interesting to hear from someone who has actually done it.

It would be difficult to stay stable for any length of time because those basic instruments give you almost no information on your angle of bank.

If you could manage to keep your spirit compass on a constant heading and keep the yarn straight, your wings would be level.

So while it would be possible, I would think you would need an experienced glider pilot and relatively calm conditions to maintain wings level for any usable length of time.

It would be interesting to hear from someone who has actually done it.

It would not be possible for even a super skilled pilot to stay stable for any length of time, because none of those basic instruments give you any information on your angle of bank. It would be no better than saying "As a skilled pilot, I can fly straight and level, by the seat of my pants with my eyes closed."

It is not possible, and it would be only blind luck if you could do it for more than a few minutes.

It would be difficult to stay stable for any length of time because those basic instruments give you almost no information on your angle of bank.

If you could manage to keep you spirit compass on a constant heading and keep the yarn straight, your wings would be level.

So while it would be possible, I would think you would need an experienced glider pilot and relatively calm conditions to maintain wings level for any usable length of time.

It would be interesting to hear from someone who has actually done it.