This problem, combined with the other one you mentioned in a different thread about funny textures on the Kirin Sport, indicate a graphics driver issue to me. Are you running the latest drivers for your gfx card?
A while back I switched from the standard ATI drivers to the Omega drivers, as the ATI drivers did not support shaders. But the funny thing is that there were no problems with textures or frame rate on 1.73. In addition, without having checked every single OXP ship, my texture issues seem to be limited to ships from one source: So far I've only seen the issue on the Kirin family and the Xarik. Also, the frame rate is - as far as I've been able to determine - unrelated to what I have my shaders set to. (But this is maybe best addressed in a separate thread - the poor Vortex already got hijacked once...)
Edit: Well, the problem appears to be solved. But I'm more confused than ever.
The story, in chronological order: When I first came across Oolite, I had no clue about shaders, I'd never even heard of them. (I'm still fairly ignorant of the technical bits, but I've learnt they make good looking things look even better.) Not until I read posts about decals did I realize that I actually didn't have shaders on my system. So I went looking for a cure. Automatic update? No help. ATI website? No help. Dell? No help. So after trying all the "official" sources, I gave the Omega drivers a go. Lo and behold! Shaders! Damn this shit looks good!
Then I install 1.74 and some new OXPs, and suddenly encounter missing textures and dropping frame rates. In a clear cut case of post hoc ergo propter hoc
I blamed one of the two, but testing gave no answers.
Inspired by a_c's suggestion of driver issues I went back to scratch. Automatic update. Run Oolite. What's this? Shaders? And textures appears fixed too. Quick test of frame rate reveals no problems, so it looks like the problem is solved.
Now here's the kicker: Checking the date on the driver, it says 23rd of May, 2006. Bizarre.
Anyway, on to the cargo problem...