Date: 201702
Local time of day: 1201-1800
Location: ASE.TRACON, CO
Flight conditions: Marginal
Light: Daylight
Aircraft: Light Transport; Low Wing; 2 Turboprop Eng
Operator: Corporate
Operating under: Part 91
Flight plan: IFR
Mission: Passenger
Flight phase: Initial Approach
Airspace: Class E ASE
ATC / advisory: TRACON ASE
Second aircraft: Light Transport; Low Wing; 2 Turboprop Eng
Reporter organization: Government
Reporter function: Supervisor / CIC; Approach
Reporter qualification: Air Traffic Control Fully Certified
Human factors: Situational Awareness
Second reporter function: Enroute
Anomaly: ATC Issue All Types; Airspace Violation All Types; Conflict Airborne Conflict; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Air Traffic Control
When detected: In-flight
Result: Air Traffic Control Separated Traffic; Air Traffic Control Issued Advisory / Alert; Air Traffic Control Issued New Clearance
Contributing factors: Airport; Airspace Structure; Chart Or Publication; Procedure
Primary problem: Chart Or Publication

Narrative: I was working as Controller In Charge when I observed the event. Aircraft X was being vectored for ILS Runway 26 approach at RIL. The RADAR controller was issuing standard vectors and altitudes. Around the same time we all notice an EGE departure heading more southbound than normal. Immediately after ZDV called and advised it looked like the aircraft was on the engine out Cottonwood procedure and would stop at 14;000. RADAR immediately turned and climbed Aircraft X to attempt and deconflict the situation. I also had them give a traffic alert. After separation was established I contacted ZDV to ask if the aircraft was actually engine out or if they had just flown the procedure wrong; the latter being the answer. After review of the FALCON replay the closest proximity was 3.83 miles and 200 feet; so RADAR was able to maintain separation for ASE approach minimums.While this report is about that single event; this is not the first time I have seen a similar situation. I'd estimate that I've seen aircraft incorrectly fly the engine out procedure on that departure without having an actual emergency at least a dozen times now over my 3 years as a CPC (Certified Professional Controller) at the facility. Only twice; including the described event; have aircraft been in conflict. Typically ASE approach does not have aircraft in the area of the procedure and usually it's not an issue except for ZDV needing to call for a quick point out. However; my issue with the situation is that under the wrong circumstances the procedures conflict enough that it could lead to a significant near miss if not worse. It is something we have talked about among ourselves as controllers and many times we have stated we should report it even without an event.The departure seems to be an unpublished procedure and I do not have easy access to it to see why it is so common for aircraft to mistakenly fly the engine out part; but that would be the first thing I would look at. Make sure it is clear what the normal procedure is and what the engine out is. I'm assuming that no other engine out procedure is available otherwise I would say have that changed to not enter ASE airspace at all.There are a few reasons I believe this situation could have dire consequences. The aircraft on this procedure do not reach ZDV's MVA until 14000 (I believe). This prevents the ZDV controller from being able to issue a heading off of the procedure prior to that altitude; which with a normal performance climb tends to be right about at the boundary of ASE airspace. So from ZDV's standpoint there is not much they can do to get the aircraft away from any potential ASE traffic. ASE RADAR limitations prevent us from being able to see the aircraft until roughly 12;500 ft. This gives us very little time to assess the situation and move our traffic out of the way of the climbing EGE departure. It is fairly common to run RIL and ASE arrivals in the airspace that the engine out procedure from EGE takes the aircraft at 13000 and 14000. In my opinion it is very believable that you could have aircraft on converging courses; climbing or descending through each other's altitude; and not knowing about the second aircraft until separation is already lost leaving very little time to avoid an accident.


Second narrative: I was working Denver ARTCC. Aircraft Y was coming off the missed approach LOC/FMS Runway 25 off of EGE. ASE Approach called with a point out on Aircraft X direct RIL to land. This coordination was not going to get near our airspace so I approved the point out. As I watched the track on Aircraft X; I realized the aircraft was not going direct RIL but tracking north towards our airspace. I called ASE back to confirm Aircraft X was direct RIL. I was told that they were direct ZELOP for the approach into RIL. I then explained that I had an aircraft coming out of EGE and that I could no longer approve the point out. The ASE Approach controller told me they would miss our airspace.Aircraft Y came out on the missed approach and instead of doing the missed approach procedure; they did the 'engine out only' procedure that enters ASE airspace. They did not have an engine out. Upon realizing that the aircraft was not flying the correct procedure; I called ASE to point out Aircraft Y. The RADAR controller stopped the departure at 14000 feet; as at the time; Aircraft X showed at 15000 feet. However Aircraft X had been cleared for the approach and was descending. The controller then gave Aircraft Y an immediate right turn heading to 360. It appeared that the aircraft turned slightly left before eventually turning right to the 360 degree heading. I am told the proximity was about 3 miles and 300 feet.Aircraft Y was told by EGE not to fly the 'engine out' procedure if they did not have an engine out. The pilot stated that they are unable to override the FMS to fly the proper procedure. The FMS is programed to fly the 'engine out' procedure. This has been and is a known problem; specifically when ASE has traffic in the north part of their airspace below 16000 feet. My recommendation is to reprogram the software or change the procedure.


Synopsis: ASE TRACON and ZDV ARTCC Controllers reported aircraft FMS databases are programmed incorrectly for the EGE Cottonwood 2 Departure causing aircraft to fly the incorrect departure procedure into confliction with ASE's ILS approach.