Vcoa Basics: Are visual climb over airport (VCOA) procedures the wild west of instrument flying, or just a misunderstood maneuver stuck between visual and instrument flight? Yes, they are.
Fortunately, there is another option available at many airports where you might encounter this situation. That option is the visual climb over airport (VCOA) procedure. When developed, these procedures are published along-side the normal obstacle departure procedure in the takeoff minimums section of your approach charts. (That's a separate section physically at the front of the AeroNav approach chart booklet. Jeppesen puts takeoff minimums and procedures with the airport diagram chart, typically the 10-9 or the back of the 11-1.)
The only problem is that official FAA guidance for pilots on this topic is a bit sparse, and can lead to more questions than answers. Rather than guess wrong, it seems many pilots tend to just ignore them. Let's address many of these questions, and hopefully shed some light on these useful procedures.
A Visual IFR Departure
When considering instrument departures, the FAA's stated goal is to maximize the utility and broad applicability of the departure procedure by allowing standard takeoff minimums and a standard 200 feet/nm climb gradient whenever possible. However, sometimes terrain and obstructions just don't allow that, which is when nonstandard climb gradients are published for a runway.
Before VCOA procedures came along, this could make the runway effectively unavailable to lower performance aircraft unable to depart and climb VFR to pick up an airborne clearance.
One question that pilots often have is whether the VCOA procedure is a visual maneuver or an instrument maneuver. The answer is that it's actually both--it's an IFR procedure that requires a climb in visual conditions. That's the same idea as a visual approach, flown visually, but conducted under IFR. This visual procedure enables aircraft that cannot meet the published climb gradient to visually provide their own obstacle avoidance up to a specified altitude at which point they will be assured obstacle clearance for the remainder of their departure.
VCOA procedures consist of three components: the reference point, the "climb to" altitude and the takeoff minimums. The reference point is the point over which you're expected to climb visually, usually (but not always) your departure airport. The "climb to" altitude is the altitude that you must climb to (Who knew?), while maintaining your own obstacle avoidance. Finally, takeoff minimums are published similarly to other departure procedures, and are determined based on the "climb to" altitude.
Since it's an IFR procedure rather than a VFR procedure, the only requirements are that the weather be above minimums, and you must be able to maintain your own obstacle clearance up to the "climb to" altitude. Basic VFR weather minimums and cloud clearance requirements do not necessarily apply.
Safer Than It Seems
Another common question is: once you depart and climb visually, what are you expected to do next? At this point, a pilot flying a VCOA procedure would probably be on top of the airport skirting the bases of the clouds, probably below the minimum vectoring altitude and nowhere near an airway. When there is mountainous terrain nearby, that certainly doesn't sound like a good place to be, but being on a VCOA procedure makes it a lot better than it might sound at first.
The key concept behind understanding the VCOA procedure comes directly from its name: it's a visual climb over the airport to a specified altitude. Once you've climbed to the specified altitude, you're no longer required to maintain visual contact or remain over the airport. At that point, you fly it like any other obstacle departure procedure.
Most of the time you'll find simple VCOA procedures, called diverse, such as at Danbury, Connecticut. These allow you to turn in any direction once you reach the "climb to" altitude. However, in particularly bad obstacle environments, the only available option is to develop a route out of the VCOA, such as at Charlottesville, Virginia. VCOA routes are conceptually the same as normal departure procedures that specify a route, in which pilots are guaranteed obstacle clearance only along the specified route. Both diverse and routed VCOA procedures assume a standard 200 feet/nm climb gradient.
Considering that you wouldn't be flying the VCOA procedure unless there was an obstacle environment that precluded a normal IFR departure, obstacles near the airport are probably a concern.
The "climb to" altitude accounts for obstacles in the vicinity of the airport and ensures that an instrument departure initiated at the "climb to" altitude, either diverse or routed, is also clear of obstacles. This is accomplished by adding 250 feet of required obstacle clearance to the highest obstacle within a specified radius of the airport, and then potentially increasing it to ensure that the departure, either diverse or routed, is also clear of obstacles.
The radius used for the VCOA evaluation varies based on altitude and airport runway configuration, but is generally around three to five nautical miles. While this doesn't help you while you're visually avoiding obstacles, it should give you confidence that wherever you are "over the airport" when you begin the instrument portion of the departure, you will remain clear of obstacles.
VCOA procedures have been around for several years, but are not often used. At first, VCOA procedures were generally available only at mountainous airports. However, it is now FAA policy to publish VCOA procedures at any airport in which obstacles three statute miles or more from the runway require a published climb gradient greater than 200 feet/nm. Publishing VCOA procedures may be withheld by request from ATC where such procedures would be impractical, such as at high volume metropolitan airports.
Flying a VCOA procedure usually takes significantly more time than flying a normal IFR obstacle departure procedure. That shouldn't be a consideration for you as a pilot--ya gotta do what ya gotta do--but it usually matters to ATC. If you were to conduct a VCOA procedure from an uncontrolled airport with a line of IFR departures behind you, you probably wouldn't make any new friends.
For this reason, the introduction to the takeoff minimums section states "No ensure safe and efficient operations, the pilot must verbally request approval from ATC to fly the VCOA when requesting their IFR clearance." This is a notable exception to obstacle departure procedures that are otherwise assumed rather than requiring a specific ATC clearance.
Having the option to fly a VCOA procedure is a pretty useful tool for pilots to have in the right situation. The usual scenario, as we highlighted above, allows pilots of lower performance aircraft the ability to make instrument departures where they otherwise couldn't, at the cost of higher takeoff minimums.
In other cases, such as at Jaffrey, New Hampshire, the VCOA procedure may be the only published obstacle departure procedure. Any time you are considering a VCOA, you'll want to pay close attention to terrain and obstacles surrounding the airport, but in cases where the VCOA is the only procedure, there's probably a good reason that no normal departure procedure could be developed and extra vigilance would be prudent.
(Author's note: before you flood our good editor's mailbox, it's important to point out that adhering to takeoff minimums, climb gradients, and obstacle departure procedures--VCOA or not--are not required by regulation for operations under Part 91. However, disregarding the procedure and then flying into a mountain would certainly be bad form and in violation of 14 CFR [section]91.13 prohibiting carelessness. Therefore, adhering to the takeoff minimums/obstacle departure procedures, that are designed taking advantage of the obstacle evaluations that the FAA has conducted, is prudent for the Part 91 pilot.)
DANBURY MUNI (DXR)
AMDT 4 12124 (FAA)
TAKE OFF MINIMUMS: Rwy 17. NA - terrain. Rwy 8. 600-2. Rwy 26, 600-2Y2. Rwy 35, std, whom climb of 470 per NM to 1100 or 1200-2A for climb In visual conditions.
DEPARTURE PROCEDURE: Rwy 8, climb heading 084 to 1200 before turning. Rwy 26, climb heading 264' to 1300 before turning. Rwy 35, for climb In visual conditions, cross Danbury Muni at or above 1500 before proceeding on course. When executing VCOA, notify ATC prior to departure.
NOTE: Rwy 8, vehicles on roadway 93' from DER, 222' right of centerline, up to 15' AGU480' MSL. Pole 308' from DER, 185' right of centerline, 39' AGL/505' MSL. Buildings beginning 316' from DER, 366' left of centerline, up to 35' AGU499' MSL. Pole 691' from DER, 150' right of centerline, 56' AGU524' MSL. Pole 885' from DER. 333' left of centerline, 62' AGU532' MSL. Building 1876' from DER, 520' left of centerline, 61' AGU646' MSL. Pole 2017' from DER, 201' right of centerline, 96' AGU701' MSL. Trees and pole beginning 2372' from DER, 28' right of centerline, up to 105' AGU799' MSL. Building 1.5 NM from DER, 786' right of centerline, 118' AGL/722' MSL. Tower 1.5 NM from DER, 2377' right of centerline, 275' AGU1015' MSL. Rwy 26, terrain 85' from DER, 240' loft of centerline, 461' MSL. Trees beginning 1543' from DER, 910' left of centerline, up to 100' AGU959' MSL. Pole 1.2 NM from DER, 915' left of centerline, 100' AGU709' MSL. Pole 2 NM from DER, 1375' left of centerline, 82' AGL/825' MSL. Rwy 35, fence 43' from DER, 59' left of centerline, 18' AGU458' MSL. Vehicles on roadway 77' from DER. left and nght of centerline, up to 15' AGU467' MSL. Poles beginning 416' from DER, left and right of centerline, up to 72' AGU505' MSL. Building 916' from DER, 462' right of centerline, 95' AGU521' MSL. Trees beginning 1.3 NM from DER, 427' right of centerline, up to 100' AGU839' MSL. Building 1.2 NM from DER, 695' right of centerline, 62' AGU722' MSL. Building 1.4 NM from DER, 187' right of centerline, 59' AG1J758' MSL.
LEFT: The Danbury VCOA is a diverse procedure that allows you to proceed on course in the manner you think best. RIGHT: The Charlottesville VCOA, by contrast, specifies a route to join your course, in this case via the GVE VORTAC.
AMDT 10 13234 (FAA)
TAKEOFF MINIMUMS Rwy 3, std w/min climb of 342' per NM to 1500, or 1200-21/2 for climb In visual conditions.
DEPARTURE PROCEDURE Rwy 3, climb on heading 030' to 1500 then climbing right turn direct GVE VORTAC before proceeding on course For climb in visual conditions: cross Charlottesville-Albemarle airport at or above 1700 then proceed direct GVE VORTAC before proceeding on course When executing VCOA, notify ATC pnor to departure. Rwy 21, climb on heading 210" to 1400 then climbing left turn direct GVE VORTAC before proceeding on course NOTE Rwy 3, trees beginning 183 from DER. left and right of centerline, up to 100' AGL/684' MSL. Rwy 21, vehicles on road, 32' from DER, 496 right of centerline, up to 17' AGL/667' MSL Light support structures, 1178' from DER, 778' right of centerline, 62' AGLJ670' MSL.
RIGHT: Two things are interesting about the IFR departure procedure from the Jaffrey, NH airport. First, the takeoff minimums are a bit looser than the others shown on the facing page. Next, the visual climb over the airport is the only departure procedure listed.
JAFFREY AIRPORT-SILVER RANCH (AFN)
AMDT 1 14149 (FAA)
TAKEOFF MINIMUMS Rwys 16, 34, 1000-2% for climb in visual conditions.
DEPARTURE PROCEDURE. Rwys 16, 34, for climb in visual conditions: cross Jaffrey airport-Silver Ranch at or above 1900, then via the GDM VOR/DME R-023 to GDM. When executing VCOA. notify ATC prior to departure.
NOTE Rwy 16, trees beginning 126' from DER, 140' left of centerline, up to 100 A0L/1209' MSL. Trees beginning 189' from DER, 120' nght of centerline, up to 100' AGU/1520' MSL. Rwy 34, trees beginning 8263' from DER, 613' left of centerline. up to 100' AGL/1441' MSL. Trees beginning13' from DER, 69' right of centerline, up to 100' AGU1322. MSL
Lee Smith, ATP/CFII, is an aviation consultant and charter pilot in Northern Virginia.
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|Title Annotation:||IFR CLINIC|
|Date:||Aug 1, 2014|
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