Talk:Longitudinal static stability
|WikiProject Physics / Fluid Dynamics||(Rated Start-class, Mid-importance)|
|WikiProject Aviation / Aircraft||(Rated Start-class)|
There are comments below, all now either invalid or actioned (corrections implemented in the article), so I think the balance of this page is defunct, and would like to delete it. That feels capricious & unilateral so I won't. Instead I'll do some research to see what the habitual techniques of maintenance and housecleaning before presuming to delete. Meanwhile, any reading this be advised (one person) thinks the article's pretty good and the below comments no longer relevant. Markrkrebs (talk) 13:29, 13 May 2012 (UTC)
In all conventional aircraft, the center of gravity must be ahead of the center of lift of the main airfoil in order to achieve positive static stability. The diagram in this article incorrectly shows the center of gravity behind the center of lift.
As the center of gravity moves aft toward the center of lift, stability decreases and is lost when the center of gravity is behind the center of lift. Some modern aircraft do fly with reduced or even negative static stability because static stability is achieved with a drag penalty created by the drag produced by the negative lift of the horizontal tail. This penalty can be reduced in civil aircraft to reduce drag and thus fuel consumption. Static stability can be virtually eliminated in some military aircraft in the interest of extreme maneuverability. There is a cost for this. These newer aircraft can only be operated safely by relying on active computer assisted controls. The controls must counter every disturbance from trimmed flight, perhaps many times per second. Otherwise these disturbances may cause the aircraft to depart controlled flight altogether. —Preceding unsigned comment added by 22.214.171.124 (talk) 16:39, 5 February 2010 (UTC)
The above asserts that; 'the drag produced by the negative lift of the horizontal tail.' I am of the opinion that the tailplane in modern commercial aircraft produce a vertically upwards lift component, not downwards. Downwards lift would make the aircraft dynamically unstable. 126.96.36.199 (talk) 07:09, 8 March 2010 (UTC) R.A.P