[lojban-beginners] Re: POM lines 1

OK, encouraged by the lack of anybody saying no, here is a first bit of dialog to critique.
(The explanation of POM and its current state is at http://www.tassos-oak.com/tempp/barsoomian.html)

The audience's first sight of the princess, Dejah Thoris, is a scene that does not appear in the book. She is discovered on the deck of her flying yacht. Her crew chief approaches her carrying a toasty-looking chunk of machinery and the following dialog occurs:
JARL THON
coi noltru ti'u ga'i nai le ti nenli'i cupra a'onai spofu

SUPER: Princess, this ray generator is hopelessly broken

(O Princess, (meekness) the this-here energy-ray producer (hope-denial) is-broken )

I have no ideo what ti'u is doing here, but since your translation doesn't reference it, I'll assume it got in by mistake.

"le ti nenli'i cupra" expands to "le nenli'i cupra pe ti", or "the energy ray producer of this". This may be sufficient for your meaning ("this" could refer to the ship), or you may wish to use ti poi nenli'i cupra.

I'd attach .a'onai to the spofu rather than the cupra. You also need a cu before spofu

ma'a na kakne lo ca'a cupra le lafti

SUPER: We cannot continue to generate lifting force.
(we-all not are-able-to the-really continued generation-of the-lifting ... does this need nu after lo?)

Yeah, it needs a nu, or a za'i might be better. You may mean "ca'o" rather than "ca'a".

DEJAH THORIS
lo zu'o vofli cu renvi fi ma?

SUPER: How long can we keep flying?
(the-truly activity-of flying, endures how-long?)
JARL THON
le go'i mleca le cacra

SUPER: Less than an hour.
(The what-you-said is-less-than [default-1] hour)

As Timos pointed out, {le go'i} doesn't work like that here. {lo cacra be li me'i pa} would probably be a good answer.