[The Red Zone]

It would depend on how large the opening was. A dome shaped glass can be thinner than a flat pane that withstands the same vacuum, just like relatively strong light bulbs can be made of very thin glass because of their globular/tubular shape.

The ship could have a pointy tip at the end of a rod to break the glass, and the rod itself made so it would break off once the ship hit air. The glass could be inscribed with break lines on the inside like a hand grenade, so that it would come apart neatly without bits getting sucked back down the tube before the ship could get all the way out.

[r9etb]

If you hit anything solid at 8 km/sec, no matter how thin it is, or how pointy you are, you're going to get a hell of a bang.

[nuke rocketeer]

And I bet there would be plenty of volunteers who would fly it up.

[SampleMan]

At the speeds we're talking about, plasma, not broken glass would be the result. Think a bird strike at 600 mph looks ugly? Try 7,000 mph. 1/2e=mass X velocity squared