a)  When vacating any previously assigned altitude  or flight level for a newly assigned altitude or  flight level b)  When an altitude change is made if operating on  a clearance specifying VFR-on-top c)  When unable to climb/descend at a rate of at least  500 feet per minute (fpm) d)  When an approach has been missed (Request  clearance for specific action (to alternative  airport, another approach, etc.)) e)  Change in average true airspeed (at cruising  altitude) when it varies by 5 percent or 10 knots  (whichever is greater) from that filed in the flight  plan f)  The time and altitude upon reaching a holding fix  or point to which cleared g)  When leaving any assigned holding fix or point NOTE: The reports in (f) and (g) may be omitted  by pilots of aircraft involved in instrument  training at military terminal area facilities when  radar service is being provided. h)  Any loss in controlled airspace of VOR,  TACAN, ADF, low frequency navigation  receiver capability, global positioning system  (GPS) anomalies while using installed IFR- certified GPS/Global Navigation Satellite  Systems (GNSS) receivers, complete or partial  loss of ILS receiver capability, or impairment of  air/ground communications capability. Reports  should include aircraft identification, equipment  affected, degree to which the capability to operate  under IFR in the ATC system is impaired, and  the nature and extent of assistance desired from  ATC. i)  Any information relating to the safety of flight. a)  When leaving the final approach fix inbound on  final approach (nonprecision approach), or when  leaving the outer marker or fix used in lieu of the  outer marker inbound on final approach (precision  approach). b)  A corrected estimate at any time it becomes  apparent that an estimate as previously submitted  is in error in excess of 3 minutes. 2.  When not in radar contact: ATC arrival procedures and flight deck workload are affected  by weather conditions, traffic density, aircraft equipment,  and radar availability. When landing at an airport with approach control services and  where two or more IAPs are published, information on the  type of approach to expect is provided in advance of arrival  or vectors are provided to a visual approach. This information  is broadcast either on automated terminal information  service (ATIS) or by a controller. It is not furnished when  the visibility is 3 miles or more and the ceiling is at or above  the highest initial approach altitude established for any low  altitude IAP for the airport. The purpose of this information is to help the pilot plan arrival  actions; however, it is not an ATC clearance or commitment  and is subject to change. Fluctuating weather, shifting  winds, blocked runway, etc., are conditions that may result  in changes to the approach information previously received.  It is important for a pilot to advise ATC immediately if he  or she is unable to execute the approach or prefers another  type of approach. If the destination is an airport without an operating control  tower and has automated weather data with broadcast  capability, the pilot should monitor the automated surface  observing system/automated weather observing system  (ASOS/AWOS) frequency to ascertain the current weather for  the airport. ATC should be advised that weather information  has been received and what the pilot’s intentions are. When the approach to be executed has been determined, the  pilot should plan for and request a descent to the appropriate  altitude prior to the initial approach fix (IAF) or transition  route depicted on the IAP. When flying the transition route,  a pilot should maintain the last assigned altitude until ATC  gives the instructions “cleared for the approach.” Lower  altitudes can be requested to bring the transition route  altitude closer to the required altitude at the initial approach  fix. When ATC uses the phrase “at pilot’s discretion” in the  altitude information of a clearance, the pilot has the option  to start a descent at any rate and may level off temporarily  at any intermediate altitude. However, once an altitude has  been vacated, return to that altitude is not authorized without  a clearance. When ATC has not used the term “at pilot’s  discretion” nor imposed any descent restrictions, initiate  descent promptly upon acknowledgment of the clearance. Descend at an optimum rate (consistent with the operating  characteristics of the aircraft) to 1,000 feet above the assigned  altitude. Then attempt to descend at a rate of between 500 and  1,500 fpm until the assigned altitude is reached. If at anytime  Any pilot who encounters weather conditions that have not  been forecast, or hazardous conditions which have been  forecast, is expected to forward a report of such weather to  ATC. Planning the Descent and Approach 10-8