On 26 February 1960, again at L'vov, CCCP-11180 crashed at the same location due to reduced longitudinal stability and control authority caused by icing of the tailplane.
22.
Another characteristic of the design was the artificial longitudinal stability that allowed equilibrating the airplane by means of the application of positive forces on the line planes.
23.
The transverse strength design of the class, coupled with light hull plating, therefore lacked sufficient longitudinal stability and proved far too flexible and weak in North Atlantic service.
24.
Too great longitudinal stability makes the aircraft " stiff " in pitch, resulting in such undesirable features as difficulty in obtaining the necessary stalled nose-up pitch when landing.
25.
The Farman III airplane was among those used at Chitila Piloting School, and reportedly had a longitudinal stability problem, and in addition the engine was under-performing on the day of the accident.
26.
For example, the redesign of the AA-1B into the AA-1C by Gulfstream involved wider-span elevators and horizontal stabilizers that produced better longitudinal stability, but were no longer interchangeable with the rudder and fin.
27.
The longitudinal stability of an aircraft may change when it is flown " hands-off "; i . e . when the flight controls are subject to aerodynamic forces but not pilot input forces.
28.
Hoskins designed the Rotorwing-Aero 3D-RV, first flying it in 1989 . The design underwent improvements over time, particularly in incorporating a raised landing gear to eliminate longitudinal stability issues and a three-bladed propeller.
29.
To ensure stability for safe flight, an LSAS ( Longitudinal Stability Augmentation System ) was introduced to compensate for the MD-11's rather short horizontal stabilizer and ensure that the aircraft would remain stable.
30.
The directional stability was now acceptable and the new ventral fins also improved longitudinal stability at high g and on landing approach, as well as delaying the onset of Mach buffet to M0.702.
