In my research I came across three fascinating letters from a civilian who was seeing and photographing things in the sky over Sussex. It is worth noting that when you write to the MoD they will show people in 30 years time!
I'd like to keep the writer's details private for now.

 - 24th August 1976 "...Archeological study of the Paleolithic Artifacts of an obvious machine culture.
The machines discovered on the photographs are engraved on the Artifact...the Tektites have the power to act in unison as a corporeal body. Their motivating power appears to be static electricity.
The power to build up high pressure for good static generation, hence the hot dry weather..."

 - 30th August 1976 "Your prompt action 05.30 27th August threw the "Tektites" completely out of gear ...Another incredible 'Set' was forming in the air as the R.A.F. arrived. The plane ploughed through the stuff, a reddish brown Fog. Probably 'Bacteria' in astronomical numbers...a vast swarm occupying hundreds of square miles...a Triple 'Entity'. The Master Mind (Not Known Luminous Balls, capable of individual movement,
several meters in diameter, provide light colouring along he Angstrom spectrum of visible light, and probably beyond, and are aware of security from the ground. The third 'Body' huge Swarms of 'Tektites' making up and filling the body of the 'sets'. I saw the mass Panic int the Air as the R.A.F. made the third pass a little after 05.30 am...the menace must be contained..."
 
- 31st August 1976 "Many hours observation of the rebuilding of the 'sets' of the 'Tektites' reaches the conclusion that the Entity is still very much intact, and unharmed. To my mind, the sets are on test and in the process of setting in sequence. The detail on the Top Level, behind a curtain of controlled cloud, the Entity uses to conceal the sets during course of construction, is now very sharp. I believe it is practising another deceit almost contemptuously. I believe it is very urgent to find the actual source at ground level, and stop it there.
The building material of the Entity covers hundreds of square miles, but one of the production lines is a few points East of this house. It can be seen to be operating every day."

AF/7464/72/S4f(AIR)
UFO sightings reported to the Ministry of Defence
YEAR TOTAL
1959 22
1960 31
1961 71
1962 46
1963 51
1964 74
1965 56
1966 95
1967 362
1968 280
1969 228
1970 181
1971 379
1972 201
1973 233
1974 177
1975 208
1976 167
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AF/7464/72/S4f(AIR)
"The numbers of UFO reports submitted to the Ministry of Defence...at the end
of 1975 this figure stood at 2,695...Since the number of reports submitted to you
in the 9 years prior to 1968 was 625 and in the 8 years after this period was 2,070,
this suggests an average increase for the two periods of almost 400%"
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AF/7464/72/S4f(AIR)
UFO Statistics - 1st January 1968 t 31st December 1972
Y'R | SATE'TES | BALL'NS | CEL'TIAL | METEORO | AIRCRAFT | MISCELL | UNEXP'D | = + DEBRIS +OBJECTS | + NATUR' ANEOUS
1968 65 10 36 3 114 30 22 280
1969 37 9 27 19 101 17 18 228
1970 9 8 31 16 97 5 15 181
1971 28 11 33 62 160 27 58 379
1972 7 28 17 2 128 5 14 201
Miscellaneous in this instance meaning: for example hoaxes, the reflection of lights on cloud, flares, fireworks, kites, lights on tall structures, photographic aberrations and bird flocks.