Either of you happen to have an estimate of how long it took for your xeno teams to work out what type the construct was? I've had a solid 15 kT of xeno vehicles on-site for about 20 months now, and it only took them one month to study the rest of the ruins on that planet.
Yes, as Steve wrote:
The annual chance for a race to successfully translate the alien language and symbology is equal to the xenoarchaeology points on the planet. For example, a Xenoarchaeology Vehicle is created with 2 components, giving it 1 xenoarchaeology point (cost about 9 BP). If a formation has forty such vehicles, the annual chance would be 40%. The chance in any given construction phase is equal to the annual chance * (construction phase length / year).
However, the implications of this are not all that obvious. Assuming that your 15kt formation consists of 47 xenoarchaeology vehicles each providing 1 Xenoarchaeology Point, that your construction phase length is the default 430000 seconds, and that you're clicking the 5–day button, then the chance per construction cycle is p = 47% * 432000/31556952 = 0.6434%. With a little arithmetic, you will find that the percentage chance that you won’t have completed the job after n construction cycles is (1−p)
n.
Thus, after 120 5–day construction cycles the chance that you won’t have completed the job is pretty good: 46.089%.
On the other hand, if you were clicking the 30–days button, then the chance of completion per cycle would be p = 47% * 2592000/31556952 = 3.8604%. After 20 cycles, the chance of not completing the job is 45.503%.
Give it a little more time. Just be aware that it isn’t linear; if you’re really unlucky it could take 10 times this long. You can see
a graph of the chance of not completing the job, or if you prefer,
a graph of the chance of success.
To guarantee a 90% chance of success, you’ll need to wait up to 357 5–day cycles. 99% chance of success will require waiting up to 714 cycles, and so on.