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If there is no published departure procedure at an airport with an approach then you can use what is referred to as a diverse departure assessment departure. I would think that you might find these in places like Kansas and Florida, but a cursory look in these areas doesn’t yield any examples.

Can anyone give examples of diverse departure assessment departures in the US or Canada?

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  • $\begingroup$ A diverse vector area (radar vectors) meets the requirements of a diverse departure assessment but uses radar vectors. These procedures are listed in the chart supplements book. $\endgroup$ – wbeard52 May 27 '17 at 21:39
  • $\begingroup$ @wbeard52 Many of the Diverse Vector Area (Radar Vectors) require a climb rate of greater than 200' per nautical mile, so they do not meet the requirements of a diverse departure assessment departure. The first airport I looked at, KSMO (Santa Monica) has a DVA(RV) departure but it would not qualify for a DDA departure because of the mountains north of it. I suspect that most would not qualify for for a DDA departure, that’s why they have radar vectors. $\endgroup$ – JScarry May 29 '17 at 4:16
  • $\begingroup$ That's interesting. If that is so, the Instrument Procedures Handbook, pg. 1-38 needs to be updated. "This type of departure procedure meets the TERPs criteria for diverse departures, obstacles and terrain avoidance in which random radar vectors below the MVA/MIA may be issued to departing traffic." $\endgroup$ – wbeard52 May 29 '17 at 21:54
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A diverse departure is a default departure procedure, named "omnidirectional" by ICAO.

To answer your question: It is normally not published. The only thing that is required on aeronautical publications is a wording preventing or limiting the use of this procedure.

BUCKLEY AFB (KBKF), AURORA, CO TAKEOFF MINIMUMS AND (OBSTACLE) DEPARTURE PROCEDURES
11013
Diverse departure not authorized.
Use published departure procedures for obstacle avoidance.

Sometimes there is a reminder that it can be used:

CANNON AFB (KCVS), CLOVIS, NM
TAKEOFF MINIMUMS AND (OBSTACLE)
DEPARTURE PROCEDURES
ORIG 15064
Diverse departure authorized all runways.

This default procedure is valid only when:

  • Not explicitly prohibited,
  • There is at least one instrument approach for the airport
  • No obstacle departure procedure (ODP) and
  • No standard departure (SID) has been published for the airport.

A diverse departure is conducted this way:

  • Cross the runway end at 35 ft, maintain heading and a 200 ft/NM gradient until 400 ft above the runway end. The 200 ft/NM gradient is TERPS' minimum climb gradient, and corresponds to ICAO's 3.3% for the minimum procedure design gradient.

  • Continue or turn in any direction while maintaining a minimum rate of climb of 200 ft/NM.

  • Maintain this rate of climb until reaching a 1,000 ft obstacle clearance or a 2,000ft obstacle clearance in mountainous areas.

enter image description here
Source

The 40:1 ratio (152 ft/NM) delimits a surface from the runway end, named the obstacle clearance surface (OCS). The diverse departure ensures being above the OCS until enroute.

Whenever the conditions exist for a diverse departure, it is implicit ATC authorities have assessed the absence of obstacle above the OCS. This assessment is named the diverse departure assessment.

Given the 40:1 slope and obstacle clearances, the area assessed may have a radius from 25 to 46 NM.

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  • $\begingroup$ Great explanation. Are you aware of any examples where it is applicable, but not listed in the Chart Supplement? $\endgroup$ – JScarry May 27 '17 at 20:07
  • $\begingroup$ In Ontario, Kincardine has two RNAV (GNSS) approaches, and no ODP/SID. Therefore a diverse departure is possible. See page 130 in the large CAP file or on this image. I was able to confirm the validity of the diverse departure because a wind farm was built and needed the area to be reassessed. $\endgroup$ – mins May 27 '17 at 21:57
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    $\begingroup$ "Continue or turn in any direction while maintaining a minimum rate of climb of 156 ft/NM (40:1 slope)." Are you sure the minimum climb rate is156ft/NM? I recall it's 200ft/NM, which is 3.3% or 2 degree. $\endgroup$ – lemonincider Sep 17 '17 at 3:22
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    $\begingroup$ @lemonincider: You're right the rate is 200 and 156 (actually 152) is the slope of the OCS. Corrected. Thanks! $\endgroup$ – mins Sep 17 '17 at 8:56
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enter image description here When you see this symbol on the approach plate, it means that either there are non-standard takeoff minimums or that there is a published departure procedure. So one way to find airports with a diverse departure is to look for ones without that symbol. It is a necessary, but not sufficient condition.

I downloaded the TPP documents for Florida and California and started looking for airports without the symbol. The only ones I found were a couple of military fields in FLorida. Kansas and Nebraska are pretty flat too so I looked at the TPP NC2 plates and found KAIA.

enter image description here

There are no notes for this approach and none of the approaches at this airport have Alternate Takeoff Minimums symbol. If you look at the approach plate there is only one obstacle several miles away and about 1800' above the airport. It would be hard to hit it with a standard IFR climb.

Dodge City, Harper Muni, Neodesha Muni, Platsmouth Muni, Pratt Regional, Smith Center Regional, Cessna Aircraft Field (but not the Beech Aircraft field just a few miles away) all have diverse departure assessment departures. So there aren’t a lot of them, but they aren’t unicorns.

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