A turboclair system basically consisted of jet engines used to warm the air around the runway and dissipate the fog. I understand that better visibility due to less fog allows less-well-equipped aircraft to land safely, but such an artificial temperature elevation may create strong turbulence (due to convection) and, thus, restrict the types of aircraft than can land safely (e.g., only heavier aircraft, which could be less affected by localised turbulence).

(I imagine that, nowadays, ILS is more effective than a fog removal system in bringing an aircraft safely to the runway.)

My question is: Because of probable turbulence due to this system, do operations into runways using a turboclair system come with additional restrictions compared to the same runway without fog?

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    $\begingroup$ We can look at the airport(s) in question, and see if the approach plates say anything about it. Do you have a specific one in mind? $\endgroup$
    – CrossRoads
    Apr 8, 2019 at 12:23
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    $\begingroup$ Not according to this book. $\endgroup$
    – fooot
    Apr 8, 2019 at 22:17
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    $\begingroup$ This sounds terribly expensive. Where has this been implemented? Anywhere? $\endgroup$ Apr 10, 2019 at 22:07
  • $\begingroup$ @RyanMortensen according to this article it has been implemented at orly airport with 14 military jet engines. $\endgroup$
    – Manu H
    Apr 11, 2019 at 16:30
  • $\begingroup$ Sounds like this could also be a way of generating some additional headwind to improve TO/landing performance. With a cost of added turbulence... $\endgroup$
    – FreeMan
    Dec 16, 2019 at 14:34

1 Answer 1


I found a Turboclair addon checklist for the SE.2 Caravelle landing procedure and it says nothing about turbulence. This procedure is intended for ferry flights without passengers and specifies the use of a braking parachute, so it is not for normal flights. It is possible that this was the checklist used during 1968-69 testing of the system before general approval and that a turbulence warning or restriction was added later, but it seems likely that any severe turbulence problem would have been recognized very early.

There are standard weather checks at the destination. There is evidently a Turboclair specific approach that must be requested and the pilot must announce arrival at outer marker, at 400ft, that he has landed and again when he has cleared the runway. He is to continue the use of instruments when on the ground due to poor visibility.

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Initial testing in 1961 was conducted using modified De Haviland SE 252 jet aircraft as heaters, which could be re-positioned to find most effective locations.

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Under construction from 1970 to 1974, the system's jet engines were permanently installed in underground pits. The reference shows the installation on Orly runway 07, remnants of which can still be seen in Google maps which now shows the runway as 06.

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The system was also installed at Charles DeGaulle airport. It was used for fewer than 1000 landings between the two airports before being decommissioned in 1982.


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