Loss of Tail Rotor Effectiveness (LTE) ensure that the nose does not continue yawing to the right. If  a go-around is required, increasing the collective too much or  too rapidly with airspeeds below translational lift may cause  a rapid spinning to the right.  Once the helicopter has landed and is sliding/rolling to a  stop, the heading can be controlled with a combination of  collective, cyclic and throttle. To turn the nose to the right,  raise the collective or apply aft cyclic. The throttle may be  increased as well if it is not in the full open position. To turn  the nose to the left, lower the collective or apply forward  cyclic. The throttle may be decreased as well if it is not  already at flight idle. pilots to not only to understand the definition of LTE, but  more importantly, how and why it happens, how to avoid  it, and lastly, how to correct it once it is encountered. We  must first understand the capabilities of the aircraft or even  better what it is not capable of doing. For example, if you  were flying a helicopter with a maximum gross weight of  5,200 lb, would you knowingly try to take on fuel, baggage  and passengers causing the weight to be 5,500 lb? A wise  professional pilot should not ever exceed the certificated  maximum gross weight or performance flight weight for any  aircraft. The manuals are written for safety and reliability.  The limitations and emergency procedures are stressed  because lapses in procedures or exceeding limitations can  result in aircraft damage or human fatalities. At the very least,  exceeding limitations will increase the costs of maintenance  and ownership of any aircraft and especially helicopters. Overloaded parts may fail before their designed lifetime. There  are no extra parts in helicopters. The respect and discipline  pilots exercise in following flight manuals should also be  applied to understanding aerodynamic conditions. If flight  envelopes are exceeded, the end results can be catastrophic. Loss of tail rotor effectiveness (LTE) or an unanticipated  yaw is defined as an uncommanded, rapid yaw towards the  advancing blade which does not subside of its own accord.  It can result in the loss of the aircraft if left unchecked. It is  very important for pilots to understand that LTE is caused  by an aerodynamic interaction between the main rotor and  tail rotor and not caused from a mechanical failure. Some  helicopter types are more likely to encounter LTE due to the  normal certification thrust produced by having a tail rotor  that, although meeting certification standards, is not always  able to produce the additional thrust demanded by the pilot. LTE is an aerodynamic condition and is the result of a control  margin deficiency in the tail rotor. It can affect all single-rotor  helicopters that utilize a tail rotor. The design of main and  tail rotor blades and the tail boom assembly can affect the  characteristics and susceptibility of LTE but will not nullify  the phenomenon entirely. Translational lift is obtained by  any amount of clean air through the main rotor disk. Chapter  2, Aerodynamics of Flight, discusses translational lift with  respect to the main rotor blade, explaining that the more  clean air there is going through the rotor disk, the more  efficient it becomes. The same holds true for the tail rotor.  As the tail rotor works in less turbulent air, it reaches a point  of translational thrust. At this point, the tail rotor becomes  aerodynamically efficient and the improved efficiency  produces more antitorque thrust. The pilot can determine  when the tail rotor has reached translational thrust. As more  antitorque thrust is produced, the nose of the helicopter  yaws to the left (opposite direction of the tail rotor thrust),  forcing the pilot to correct with right pedal application  (actually decreasing the left pedal). This, in turn, decreases  the AOA in the tail rotor blades. Pilots should be aware of the  characteristics of the helicopter they fly and be particularly  aware of the amount of tail rotor pedal typically required for  different flight conditions. A helicopter is a collection of compromises. Compare the  size of an airplane propeller to that of a tail rotor. Then,  consider the horsepower required to run the propeller. For  example, a Cessna 172P is equipped with a 160-horsepower  (HP) engine. A Robinson R-44 with a comparably sized tail  rotor is rated for a maximum of 245 HP. If you assume the  tail rotor consumes 50 HP, only 195 HP remains to drive  the main rotor. If the pilot were to apply enough collective  to require 215 HP from the engine, and enough left pedal to  require 50 HP for the tail rotor, the resulting engine overload  would lead to one of two outcomes: slow down (reduction  in rpm) or premature failure. In either outcome, antitorque  would be insufficient and total lift might be less than needed  to remain airborne. Every helicopter design requires some type of antitorque  system to counteract main rotor torque and prevent spinning  once the helicopter lifts off the ground. A helicopter is heavy,  and the powerplant places a high demand on fuel. Weight  penalizes performance, but all helicopters must have an  antitorque system, which adds weight. Therefore, the tail  rotor is certified for normal flight conditions. Environmental  forces can overwhelm any aircraft, rendering the inherently  unstable helicopter especially vulnerable. LTE is a condition that occurs when the flow of air through  a tail rotor is altered in some way, by altering the angle or  speed at which the air passes through the rotating blades of  the tail rotor disk. As discussed in the previous paragraph, an  effective tail rotor relies on a stable and relatively undisturbed  As with any aerodynamic condition, it is very important for  11-18