KJakker 902 Posted April 8, 2016 How low must a subsonic passenger jet fly in order for its engines to be heard on the ground? I am asking because I was just doing some work outside my house and while I was in the garage I started to hear jet engine noise and stepped out to see if I could see any A-10's from the ANG base which is about 60 miles south of where I live, they are the only jets that I normally hear, but when I looked up I saw an airliner that had just passed overhead heading about NNE, it appeared to be low as I could clearly make out the fuselage, wings, and horizontal stabilizers yet it still had contrails coming off its wings. Unfortunately I could not get to a camera before it was out of sight. Hearing and seeing it like that just seemed odd as there are no airports near enough for it to be in a lower attitude holding pattern, everything that is not military or small private aircraft stays up high enough I can usually blot it out with the tip of my little finger. So here's the question, being 650 ft above sea-level and with the following conditions... Wind: NE Wind Speed: 9mph Temperature: 40°F Humidity: 52% Pressure: 29.77 in UV Index: 0 Cloud Cover: 88% Ceiling: 11500 ft Dew Point: 18° F Visibility: 10 mi ...What altitude could this aircraft have been at? PS. I just a thought, I can't remember the color of the aircraft's belly but it could have been one of the tankers out of the Air National Guard base. Share this post Link to post Share on other sites
+1977Frenchie 1,038 Posted April 8, 2016 I live under a trans-atlantic ''route''. Every aircraft inboud for Montréal Trudeau airport fly over and i hear them everytime. if i recall well, they are between 28k to 32 k feet of altitude when they get over here (i live 900km East of Montréal). I can easely hear the Canadian Air Forces C-130, CF-18 and Polaris aircraft when they land at Sept-Îles Airport, landing pattern is right beside my house, along with some civilian carriers... So my guess is that Under cetain condition, you might see them at the same altitude as me and still hear them, but yours was way lower then the one i see here. Share this post Link to post Share on other sites
Fubar512 1,350 Posted April 9, 2016 Out at sea, on a calm day aboard a drifting boat, one can faintly hear civilian airliners flying at contrail altitude, or about 28k feet or so. Share this post Link to post Share on other sites
MigBuster 2,884 Posted April 9, 2016 Could you find it on here? https://www.flightradar24.com Share this post Link to post Share on other sites