Science fiction — especially on TV — does a wonderful job of ignoring obvious problems, or waving them away with a little exposition. The most obvious issue is translation; whether it be Babel fish, universal translators, or a field imparted by the TARDIS, somehow various disparate cultures all manage to be understandable to one another in modern English. Idioms translate perfectly and, even more incredibly, lips synchronise with the ‘translated’ speech.
Translation isn’t a problem in the Stargate universe, where cultures that have descended from people who left Earth thousands of years ago seem to have evolved their languages to be very close to modern American English. No need for translation devices if everyone conveniently speaks the same tongue.
But although this lucky example of parallel linguistic evolution cures one problem, the stargate itself introduces many others. Its physics-bending rules of operation seem somewhat ‘flexible’ depending on what is demanded of the plot at any given time. So it’s not surprising that the orientation of stargates tends to be ignored — you can apparently fly your puddle jumper into an orbiting stargate any way you wish, and you’ll emerge in Atlantis the right way up.
Perhaps there’s a self-righting mechanism in the stargate system — goodness knows there are enough safeguards in the operating system that overriding them is a key point of many plots — but how does it know which is the right way up for a puddle jumper, or wraith dart?
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G1: I still can't believe we had this Stargate in a museum for all those years, thinking it was just another archaeological artefact we'd dug up in the desert
G2: But at least we know its real purpose now, and we're restoring it back it to its original location
G2: Just in time, too. That must be the visitors from Earth arriving
[Scene shows the SG-1 team falling to the floor from the "top" of the stargate]
G1: Oh… so it needs to go *that* way up…
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Gravity, obviously. We know that these wormholes are bent and effected by gravity, it’s probable that they twist towards their local gravity. It might even just be a part of the design of the physics.
That might make some sense when considering the SG-1 team walking into the gate, but it doesn’t really address the issue of a puddle jumper flying into an orbiting stargate at the wrong angle. In Stargate: Atlantis they often flew into a gate at one angle relative to local gravity (as extrapolated from the big CGI planet in the background), but always came out right-side-up in Atlantis. Either the gate system knows which way up a puddle jumper should go and compensates accordingly… or it’s just a TV programme that ignores such details for dramatic effect.
My money’s on the latter 😉
Only one side of the Stargate can be used to transport matter.
I’m not sure how that affects the joke, or commentary. We’re not talking about “back” vs “front” of the stargate, but rather “top” vs “bottom”. Consider an SG team walking through the bottom of the gate whilst a UAV flies through the top – what happens at the other end if the gate is upside down so that the top chevron is at the bottom?