Wind effect on Obstacle and Climb Limited TOM
Thread Starter
Joined: Jun 2011
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From: Portugal
Wind effect on Obstacle and Climb Limited TOM
I am still 2 subjects away from my ATPL(A) and there is a something that I am having trouble understanding. It is one of the question in the Bristol DB.
It has to do with Obstacle and Climb Limited TOM.
I just donīt see how can tailwind affect OLTOM and no CLTOM...as I see it they are almost the same. The first requires an Obstacle Clearance and in order to do that we need a certain Climb Gradient, and the other requires a designated Climb Gradient. So both should be affacted by wind...or not...
Any help?????
Thanks
It has to do with Obstacle and Climb Limited TOM.
I just donīt see how can tailwind affect OLTOM and no CLTOM...as I see it they are almost the same. The first requires an Obstacle Clearance and in order to do that we need a certain Climb Gradient, and the other requires a designated Climb Gradient. So both should be affacted by wind...or not...
Any help?????
Thanks
Joined: May 1999
Posts: 1,846
Likes: 4
From: Bristol, England
The Climb Limited TOM is controlled by the requirement to make a still air gradient - hence wind cannot affect it. The Obstacle Limited TOM is controlled by a requirement to clear obstacles by a given margin, and this is affected by wind. Headwinds improve the aircraft's gradient relative to the ground (and thus increase the Obstacle Limited Mass) and tailwinds degrade it.
The Climb Limited TOM used to be called the WAT Limit, because only Weight, Altitude, and Temperature affect the still air climb gradient. I've always thought that a much less confusing name.
The Climb Limited TOM used to be called the WAT Limit, because only Weight, Altitude, and Temperature affect the still air climb gradient. I've always thought that a much less confusing name.
