That this layer was present at the time and lil the area is indicated by the
failure of the aircraft rudar to detect the Louisiana coa~tline even
though burn-off flares on the shore were visible to the unaided eye.
The layer was probably slightly stronger at the tim~ of the incident,
thus constituting a thick radio duc~. A transmitter located above a
radio duct and emitting a high enough frequency to be affected, as the
radar un oubtedly was, does not excite propagation within the duct. This
implies that the coastline below the duct would not be visible to the
radar located above the duct.
The strange moving targets scen on the radar were probahly
caused by imperfections in the atmospheric layer forming the radio
duct, allowing the radio energy to enter the ducting layer at
various points. TIlis would create sporadic ground returns. The
returns may have been caused by a series of gravity waves running
along the Jucting layer in a Sf direction; this is a phenomenon
which is at present only poorly understood. In any event, spurious
radar images have often been noted 'mder propagation conditions of
this sort, often moving at apparent speeds of from tens to thousands
of mlles per hour.
In sununary, it seems most likely that the cause of this sight-
ing can be assigned to radar AP, for which there is meteorological
evidence, and meteors.
7-C. Whitt;; Sands ~Iissile Range, N. M., 2 March 1967, 1025-
1132 LSI. Weather: apparently clear (few meteorological data are
available), A single witncss at the sUlJlmit of highway 70 over the
Sacramento Mountains (Apache Summit, 9,DOO ft. elevation) rCllorted
seeing "silvery specks" plissing overhead from north to south. The
wi tness called Hollom~n AFB, and Tllnge ~urvei 11,lnCC radar was requested
to look fOT the objects. Two aircraft were scrambled, but neither
reported a ~ighting, although they searched ~hc arca where the UFOs
were reported.
223
That this layer was present at the time and in the area is indicated by the
failure of the aircraft lauar to detect the Louisiana coa~tlinc even
though burn-off flares on the shore were visible to the unaided eye.
The layer was probably Slightly stronger at the timt of the incident,
thus constituting a thicK radio duct:. A transmitter located above a
radio duct and emitting a high enough frequency to be affected, as the
radar un cubtedly was, does not excite propagation within the duct. This
implies that the coastline below the duct would not be visible to the
radar located above the duct.
The strange moving targets seen on the radar were probahly
caused by imperfl~ctions in the atmospheric layer forming the radio
duct, allowing the radio energy to enter the dueting layer at
various points. 11lis would create sporadic ground .. etuTns. TIle
returns may have been caused by a series of gravi ty waves running
along the ducting layer in a SE direction; this is a phenomenon
which is at present only poorly understood. In any event, spurious
radar images have often been noted ~nder propagation conditions of
this sort, often moving at apparent speeds of from tens to thousands
of mIles per hour.
In summary, it seems m05t likely that the cause of tlds sight-
ing can be assigned to radar AP, for which there is meteorological
evidence, and meteors.
7-C. Whit.,; Sands ~Iissile Range, N. M., 2 March 1967, 1025-
1132 LSI. Weather: apparently clear (few meteorological data are
avai lable), A single wi tncss at the sUlluni t of hi.ghway 70 over the
Sacramento Mountains (Apache Summit, 9,DOO ft. clevation) reporter!
sCE.'ing "Silvery ..;pel.:ks" plissing overhead from north to south. The
witntOss called Hollol1lun AFP" and T[lnge ~urveilLmcc radar was requested
to look for thE.' objects. Two aircraft were scrambled, but nc.ither
reported a sighting. although they searched ':he area where the UFOs
were reported.
223