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. 

## 2. When not in radar contact: 

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. 

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 

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 

