What is the purpose of the 'fins' mounted to the fuselage directly below the vertical stabilizer? Additional vertical stability?
What is the purpose of the 'fins' mounted to the fuselage directly below the vertical stabilizer? Additional vertical stability?
Increase stability during barrel rolls...obviously.
It all boils down to Dutch Roll.
The 25 and 35 require 2 yaw dampers to be active and 1 to be engaged at all times with exceptions for single engine situations and partial flap landings.
The dorsal fin modification (as shown in the picture, standard on 31 and later series, optional on 25 and 35) changed the requirement to 1 yaw damper...a big savings in maintenance and certification.
They also eliminate the need for a stick pusher.
Does anyone know why some of the older lears have a bunch of little "tabs" sticking up in different angles on both wings?
They provide a weather vane tenancy (similar to the feathers on an arrow) and damp out Dutch Roll
Ie: better stability
That is just the wording I read somewhere about them, so I am not sure. But my understanding was that that damps out dutch roll tendencies.Really? I thought they were there to assist in pushing the nose over during a stall situation. Why would you want to add something that causes an airplane to weathervane?
That is just the wording I read somewhere about them, so I am not sure. But my understanding was that that damps out dutch roll tendencies.
Really? I thought they were there to assist in pushing the nose over during a stall situation. Why would you want to add something that causes an airplane to weathervane?
Why would you want to add something that causes an airplane to weathervane?