When flying the Longitude the other night I noticed that the contrails are black at night. Looked like engine trouble or something. Although it’s night condensation is condensation and the only time you get dark black smoke coming out the the engine is when there’s a problem with the engine both d…

Black Contrails at night

VAUGHAN269 September 23, 2021, 2:25pm 11

Further to my last comment, here is an example to illustrate the issue
a320 black contrails 1