Contrails possible at low altitudes?

[BWI Scott]

Hi,
I'm just wondering if it's possible to have a plane leave a contrail at a low altitude?I mean do you just need to have cold enough temps?It's been pretty damn cold here recently and that got me thinking about it.

Thanks
Scott

[LRJet Guy]

I'm not really sure. The other day in cruise at FL390, the other traffic above 370 wasn't making any contrails. Everything from the mid 20's the 350 was.

[NWFLYER_MKE]

Yes it is possible Last year when the temps were around 0 F I watches a few planes a few minutes from departure and the MD-88 that I saw was shooting a very low density trail. The plane was about 2,500 ft. The trail disappeared after a minute. So anything can be possible! :D

[AC_A340-500]

I saw contrails coming from a Dash-8 flying overhead between FL 120 and 150 (my estimate) in Edmonton during the late afternoon. It was late September and the ground temperature was 15 degrees. Also there was a big high pressure system over us, and the relative humidity on the ground was very low. (Not sure if any of that information is important or relevant).

I had never seen contrails coming out of an aircraft flying that low before.

[BWI Scott]

Thanks for the replies guys.

I think it would be very cool to see some contrails like that.I haven't seen any but it sure has been cold here.

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Scott

[PIAA310]

Dear Scott, I don't know if they are possible at really low ALT, but if it is cold enough -10------ -20 Then you might see some contrails at lower ALT's. I have never thought about this question, i will ask some one and get back to you with the right answer.


-PIAA310

[Freightdogg]

Hi,
I'm just wondering if it's possible to have a plane leave a contrail at a low altitude?I mean do you just need to have cold enough temps?It's been pretty damn cold here recently and that got me thinking about it.

Thanks
Scott

Scott,

Contrails are possible any time the outside air temperature is cold enough. The reason that they are rarely seen at low altitudes is because low altitude air tends to be more turbulent or less stable due to temperature variations cause by uneven ground heating and also due to the lifting effect of airflow over uneven terrain. In order for contrails to be noticeable there has to be a very stable layer of air for them to form and remain for a while. This is why they are more frequently seen in winter, even at high altitudes. Winter air tends to be more stable. During summer the lifting effects of uneven heating can prevent contrail formation even at the flight levels despite the fact that the outside air temperature is not significantly different than during winter.

[a78jumper]

I have seen contrails off departing jets at YEG on a really cold day, ie -35F and colder. Ever notice how the engines sound a lot different when it is really cold as well?
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[Chris Kilroy]

I have heard stories of Dash 7s making contrails several thousand feet up in the coldest parts of Alaska, where ground temperatures were -55f or lower.

[screaming_emu]

I've seen contrails forming right at the exhaust of the engine in the RJ85 during climbout from GFK. Not exactly sure what altitude, but I'd guess anywhere from 4-6k.