3 satellite appearing objects travelling over Langley on two separate nights in triangle formation from north to south.

I observed 3 satelites (in apperance and in orbit) travelling from north to south on Tuesday evening at 10:35PM (approx)for 4 minutes. They were in exact relationship (unmoving except in direction of travel)to each other. I first saw them at bout 70 degrees up to the south through binoculars while watching satellites and observed them travel to the horizon. I saw them again on Friday night but a bit earlier with their meeting the horizon at 10:16 PM on the same trajectory. I suspect they are satelies of some kind of experiment but could not find any help on the web. Please inform.
We suspect the witness may have seen the "triplet" of satellites, thought to be part of the U. S. Navy "NOSS" satellite system.  PD