Daytime ufos that appeared above Farmington New Mexico in 1978.

We were all sitting on our back porch relaxing when my sister noticed three circular objects above the foothills behind our house. The foothills were about three miles from our back porch. My sister told us all to look at these crazy things above the hills. As we all watched them, it appeared as if they were performing some kind of odd ballet in the sky. They kept darting back and forth horizontal to the horizon at great speeds, but we were wondering how the kept from hitting each other as they seemed to dart in and out of each other. the opjects seemed to look like the moon when you can see it in the daytime. (wierd description I know but they seemed illuminated like that.) they darted along for several minuets after we spotted them, and at one point they all started moving to our right along the horizon and gained speed and then moved rapidly up at about a 45 degree angle and dissapeared in less then a second. We did not think of it at the time but the radio we were listening to became heavy with static.
Date in April 1978 is approximate.  PD