Background: Roberts Field (KRDM) in Redmond, Oregon, and the surrounding terminal environment have intense, high-volume activity that includes air carrier, flight training, firefighting, and general aviation operations. The airport geometry, operating habits of airport users, and the lack of surveillance tools in the tower create a complex operating environment.

LTA Purpose: Provide pilots with flight safety considerations when operating in the central Oregon area or near KRDM, to reduce the risk of traffic conflicts and increase safety margins.

For ADS-B equipped aircraft:  When flying VFR within 25 miles of the DSD VORTAC, Seattle Center encourages pilots to broadcast ADS-B Flight ID at all times, squawk 1237 and monitor frequency 126.15.

Squawking 1237 while broadcasting Flight ID, will force the display of your flight ID onto the controllers’ radar display and indicate to the controller that 126.15 is being monitored.  

Making the Flight ID available for the controller will result in more efficient and expeditious pilot/controller communications when:

•  Controllers issue traffic calls and safety alerts, which may be issued in the blind for the benefit of pilots monitoring 126.15.
•  Requesting flight following.
•  Requesting a “Corridor” transition advisory.

Standard Operating Procedures: In order to provide stable and predictable flight paths in the Redmond area, Seattle Center controllers utilize RNAV/ILS approaches to the KRDM airport with IFR arrivals and will issue runway heading to departures as much as feasible.  If a visual approach is used, expect clearance over an RNAV FAF or vectors to set-up for a 5-mile final to the assigned runway. 

Pilots operating near KRDM, are advised to obtain the KRDM ATIS for current runway-in-use information to enhance situational awareness. Aircraft arriving runways 5 & 29 encounter traffic in the arrival paths, causing TCAS TAs and RAs, resulting in unstable approaches.  Additionally, Aircraft operating outside the RDM Class D along the extended centerline of Runway 23 may interfere with the ILS Approach and should avoid loitering in this area.

Attached are depictions of KRDM arrival corridors for RWY 5 and 29. The numbers within the segments list the top and bottom altitudes of the airspace segment in hundreds of feet MSL and indicate the area most commonly flown by IFR aircraft. For instance, on the segment beginning at SMRDK, the altitudes to avoid are between 9,500 ft and 6,500 ft.

When operating in the Central Oregon area without receiving VFR traffic advisories, ATC displays Mode C, but it is not verified and cannot be used for separation purposes. ATC recommends corridor transition calls to verify Mode C, reduce conflicts, and avoid approach cancellations.

Aircraft not receiving VFR traffic advisories are advised to avoid the KRDM final approach/departure corridors or request advisories to transit the corridors for RWY’s 5 & 29 by using the following procedures:

Pilot: “N1234 request (RWY 5) corridor transition.”

ATC: “No IFR traffic in corridor.” – Implies transition of corridor can be accomplished without conflict with IFR aircraft.

ATC: “Traffic in corridor, advise you avoid.” - Please remain clear of the corridor. This indicates that the controller believes there is a potential conflict with IFR aircraft or may be too busy to provide more detailed information about the potential traffic in the area.

Workload permitting, ATC may advise you of inbound traffic within the corridor. For example: “E175 traffic, ZIBID, inbound RNAV Y Runway 5.” The controller is providing traffic information that a transition of the corridor on your present track won’t result in a traffic conflict, but deviations from your current track could result in a conflict.

 Airborne Hot Spots:

• DSD VORTAC at and below 8,000 ft: Utilized for holding practice and multiple IFR procedures for the area converge over DSD .
• KRDM inbounds to Runway 5, crossing KBDN departures and arrivals navigating via DSD.
• KRDM inbounds to Runway 29, crossing aircraft transiting between S39 and KBDN.
• KRDM ILS encountering traffic loitering outside the Delta Airspace near the localizer.

 Non-towered KRDM operations:

• Due to buildings obstructing the view of crossing runway ends and the presence of short taxi durations, it is crucial for pilots to monitor the CTAF for an extended period to maintain situational awareness of the active runway(s) and the location of other aircraft.

NOTE- UNICOM should not be used as CTAF during non-towered operations.

• Local flight schools and corporate aircraft park on the south and north ramps respectively. These operators favor Runway 11.
• The air terminal is on the west side of the airfield, airlines often depart from Runway 05 and arrive using Runway 23.
• Whether operating IFR or VFR, pilots should broadcast accurate and descriptive position reports, state their intentions, and coordinate with other operators on CTAF to de-conflict flight paths.
• In accordance per Advisory Circular 90-66C, pilots should consider current traffic flow as well as wind direction and align/de-conflict their arrival or departure paths to the maximum extent possible to reduce the risk of collision and enhance safety.