for sharing the following.
World War 2 aero-engines were very heavy consumers of engine oil as well as fuel. They left large quantities of semi-burned engine-oil aerosol in their vapour trails that was especially visible when engines were stressed or dogfighting and when they were at at ultra-high altitude trying to avoid enemy fighters.
Comparing aerosol/particulate-laden trails of dirty WW2 piston-driven aero-engines with efficient modern jet contrails (condensation) is a red herring. The real comparison should be between modern (cleaner) jet aircraft from the 1970s onwards that produced short contrails, compared to jets with much longer aerosol-filled 'chemtrails' that can stretch out for tens of miles.
Another useful comparison is that between normal short contrails of a modern jet flying adjacent to a lengthy 'chemtrais' of aerosol-spraying jets that are geoengineering etc..
The end of a genuine contrail (condensation) always follows and keeps pace with the generating aircraft because the engline-heat is the source of the condensation in the air.
The end of a 'chemtrail' aerosol however gets left behind the aircraft as it moves away from the point in the sky where it first started spraying/seeding/geoengineering.
"Persistent contrails" are a science-abusing propagandist's myth. Condensation cannot persist without an adjacent heatsource in cold air. The persistent chemtrails evident in the skies from the 1990s onwards are often hanging around for half an hour plus after the engine heatsource has gone. Condensation trails (as opposed to aerosol 'chemtrails') cannot do that.
Merlin Engine Oil Consumption: "Merlin 76 drinks 34 pints an hour at maximum continuous power."
Extracts from Jeremy Flack's 1985 'Spitfire - Aliving Legend' book are attached herewith.
WW2 fighters and bombers often used differing numbers of the same engine. See the following for comparison:
WW2 mid-level fighter dogfight trails:
WW2 high-level B17 bomber trails:
Jet aerosol 'chemtrail' geoengineering in 2011: