BY ORDER OF THE SECRETARY OF THE AIR FORCE AIR FORCE ...

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AFMAN 11-217V1 3 JANUARY 2005
Chapter 9
IFR DEPARTURE PROCEDURES
9.1. Introduction. Arriving at an airport is usually the focus of most of our attention;
however, in many cases, departing an airport under IFR is a more hazardous operation.
When planning a mission, aircrews must ensure they cannot only arrive safely, but also
depart safely. This planning must be accomplished prior to arrival at the destination.
Arriving aircraft have several advantages over departing aircraft.
9.1.1. Performance. Mainly due to fuel consumption enroute, arriving aircraft are
typically lightweight and thus have a higher performance capability. Departing aircraft
are much more performance-limited and may have difficulty achieving the minimum
required climb gradient.
9.1.2. Established Routing. Clearly established routing is almost always available to
arriving aircraft. Normally, there will be several published instrument approach
procedures to choose from that will provide a safe route to the airport of intended
landing. A departing aircraft, on the other hand, may be faced with an extensive array of
IFR departure procedures with little or no accurate information about obstacles in the
terminal area. Some, but not all obstacle data may be depicted on individual IAPs or
published departure procedures and routings.
9.2. Planning an Instrument Departure. Prior to departure, consideration must be given to
terrain and/or obstacles on or in the vicinity of the airport. Pilots must use all available
sources to select the most appropriate departure method, which will ensure proper terrain
and/or obstacle clearance. Consideration must be given to degraded climb performance and
the actions required in the event of loss of thrust during the departure.
9.2.1. Except for diverse departures, instrument departure procedures are preplanned IFR
procedures that provide obstruction clearance from the terminal area to the appropriate en
route structure. If an airport has an instrument approach procedure, then it has also been
assessed for an instrument departure. The primary purpose of instrument departure
procedures is to provide obstacle clearance protection information to pilots. At busier
airports, a secondary purpose is to increase efficiency and reduce departure delays.
9.2.2. Published departure procedures must meet the same requirements as approach
procedures. Approval of non-DOD/NACO departure procedures is IAW AFI 11-202,
Volume 3 General Flight Rules.
9.3. Obstacle Clearance Surface (OCS). In order to assess the airport for instrument
departures, the TERPS specialist looks for obstacles along an obstacle identification surface
(OCS) on a 40:1 slope from at or above the departure end of the runway. The 40:1 slope is
equivalent to a 2.5% gradient or 152 feet per nautical mile. TERPS also requires a certain
amount of required obstacle clearance (ROC). Historically, the standard ROC has been 48
feet per nautical mile (ft/nm), which when added to the standard OCS of 152 ft/nm equates to
the standard minimum climb gradient of 200 ft/nm. The FAA has recently changed the ROC
from a standard 48 ft/nm to a formula based on 24% of the climb gradient required to clear