HI.VIII.B.R2e

From the FAA library

• Helicopter Flying Handbookp. 11-9
  Chapter 11: Helicopter Emergencies and Hazards › Vortex Ring State

  helicopter begins to descend vertically, it settles into its own downwash, which greatly enlarges the tip vortices. In this vortex ring state, most of the power developed by the engine is wasted in circulating the air in a doughnut pattern ... result, the airflow of the inner blade sections is upward relative to the disk. This produces a secondary vortex ring in addition to the normal tip vortices. The secondary vortex ring is generated about the point on the blade where…

• Aeronautical Information Manualp. 7-4-4
  Chapter 7. Safety of Flight › Section 4. Wake Turbulence › 7-4-4. Vortex Behavior

  Vortex Movement Near Ground - with Cross Winds 5. Pilots should be alert at all times for possible wake vortex encounters when conducting approach and landing operations. The pilot is ultimately responsible for maintaining an appropriate interval, and should consider ... vortices can rise with the air mass in which they are embedded. The effects of wind shear can cause vortex flow field “tilting.” In addition, ambient thermal lifting and orographic effects (rising terrain or tree lines) can cause a vortex…

• Helicopter Flying Handbookp. 10-5
  Chapter 10: Advanced Flight Maneuvers › Steep Approach

  considered a steep approach. [Figure 10-4] Caution must be exercised to avoid the parameters for vortex ring state (20–100 percent of available power applied, airspeed of less than 10 knots, and a rate of descent greater than ... feet per minute (fpm)). For additional information on vortex ring state (formerly referenced as settling-with-power), refer to Chapter 11, Helicopter Emergencies and Hazards. Figure 10-4. Steep approach to a hover…

• Aeronautical Information Manualp. 7-4-1
  Chapter 7. Safety of Flight › Section 4. Wake Turbulence › 7-4-3. Vortex Strength

  Vortex Strength a. Weight, speed, wingspan, and shape of the generating aircraft’s wing all govern the strength of the vortex. The vortex characteristics of any given aircraft can also be changed by extension of flaps or other wing configuring ... devices. However, the vortex strength from an aircraft increases proportionately to an increase in operating weight or a decrease in aircraft speed. Since the turbulence from a “dirty” aircraft configuration hastens wake decay, the greatest vortex strength occurs when…

• Aeronautical Information Manualp. 5-6-7
  Chapter 5. Air Traffic Procedures › Section 6. National Security and Interception Procedures › 5-6-8. Foreign State Aircraft Operations

  paragraph 5-6-4 and any other national security requirements in paragraph 5-6-2. b. Diplomatic Clearances. Foreign state aircraft may operate to or from, within, or in transit of U.S. territorial airspace only when authorized ... State Department by means of a diplomatic clearance, except as described in subparagraph 5-6-8i below. 1. Information about diplomatic clearances is available at the U.S. State Department website https://www.state.gov/diplomatic-aircraft-clearance-procedures-for-foreign-state-aircraft-to-operate-in-united-states-national-airspace/ (lower case only). 2. A diplomatic…

• 14 CFR Part 47 — Aircraft RegistrationOpen
  14 CFR § 47.9 Corporations not U.S. citizens.

  certificate of incorporation; (2) A certification that it is lawfully qualified to do business in one or more States; (3) A certification that the aircraft will be based and primarily used in the United States; and (4) The location where ... will be maintained. (b) For the purposes of registration, an aircraft is based and primarily used in the United States if the flight hours accumulated within the United States amount to at least 60 percent of the total flight hours…