||Aviation in Canada Blog
This week's topic:
Contact & Visual Approaches
Definitions, Contact and Visual Approach
There are a lot of differences of opinion with regard to Contact and Visual Approaches, both online and in the real world. Despite that fact, many ATC will generally apply them the same way. Many pilots regard them with some questions, so hopefully we can make the air clear enough for use of both types without raising too many new questions.
Contact Approach: According to the AIP, RAC 9.6.1, a Contact Approach is an approach wherein an aircraft on an IFR flight plan or flight itinerary having an ATC clearance, operating clear of clouds with at least 1 NM flight visibility and a reasonable expectation of continuing to destination airport in those conditions, may deviate from the Instrument Approach Procedure and proceed to the destination airport by visual reference to the surface of the earth.
Visual Approach: The AIP, in RAC 9.6.2, says a visual approach is an approach wherein an aircraft on an IFR flight plan, operating in Visual Meteorological Conditions (VMC) under the control of ATC and having ATC authorization, may proceed to the airport of destination.
Sound similar, don't they? They are in many ways. They are also quite different in application and flexibility, too. Each has it's own set of restrictions and each offers advantages over the other.
For a Contact Approach, the only weather minimum that exists is the 1 NM flight visibility. This means there is technically no ceiling requirement to meet. The idea here is to allow an aircraft to fly an approach visually under conditions that may, or may not, be VFR. In a control zone, for example, you need a ceiling of 1,000 feet and a visibility of 3 NM to meet VFR weather conditions. To conduct a Visual Approach, as you'll see later in more detail, you need significantly more than these numbers. An aircraft can do a Contact Approach in worse weather than either of these sets of criteria. There come some hazards with a Contact Approach, though, in many conditions under which these could be used.
A pilot wishing to conduct a contact approach must request it. ATC is not allowed to initiate a Contact Approach. Many controllers have said things like, "A contact approach is available on your request...," to remind a pilot that he has another option, but ATC cannot clear an aircraft for a Contact Approach without the pilot's request. A pilot may not conduct a Contact Approach without a clearance from ATC. Additionally, there has to be some form of functioning instrument approach aid at the airport, or a GPS or GPS overlay approach published. An ILS off the air doesn't qualify, but an NDB approach with the NDB functioning does, for example.
Regardless of the ATC environment (terminal with radar or otherwise), only one aircraft can be cleared for a Contact Approach at a time. This is because the aircraft doesn't have to see the airport in order to conduct an approach and his flight path may not be straight in. The pilot must maintain at least 1,000 feet above the highest terrain or obstacle within a 5 NM radius until he attains the visual reference required to continue with a landing, and he must maintain a flight visibility of at least 1 NM throughout the approach. This means the pilot may have to deviate around clouds to keep the ground in sight. ATC must maintain separation from other IFR aircraft while an aircraft conducts a Contact Approach. This may mean holding other aircraft at altitudes that allow the for the maneuvering of the aircraft on the Contact Approach, and it will likely also mean holding departures on the ground until he lands. Since ATC cannot dictate the flight path used, departure vs. arrival separation standards are difficult, if not impossible, to apply. If a missed approach is necessary, for whatever reason, terrain and obstacle clearance is the pilot's responsibility, even if detailed missed approach instructions have been received and acknowledged by the pilot. The pilot is also responsible for adherence to any noise abatement procedures and avoidance of Class F airspace. With all this in mind, requesting a contact approach in low visibility should be conducted only if the pilot is familiar with the destination airport's surrounding terrain and other geographical features.
For a Visual Approach, the weather minima are much higher. This is to allow the greater flexibility for both the pilot and ATC. The reported ceiling must be 500 feet above the appropriate Minimum IFR Altitude and the visibility must be at least 3 NM. Where a Minimum Radar Vectoring Altitude is established, this is the applicable altitude for the preceding statement. Otherwise, find an applicable altitude for the airport, such as the highest quadrantal altitude from an approach plate. Remembering that cloud heights on METAR weather sequences are heights above ground, this may not be as restrictive as it sounds. For example, at the Greater Moncton International Airport (CYQM), the MRVA close to the airport is 1,800 feet and airport elevation is 232 (which we will round off to 200 feet for simplicity). The minimum altitude we need for the cloud base is 2,300 feet ASL (1,800 + 500). Take away the height of the aerodrome and you have a cloud height requirement of 2,100 feet. If the ceiling reported in the METAR sequence is 2,100 feet or greater, you have that portion of the weather minima on your side. Remember also that this is a ceiling requirement, not a lowest cloud layer requirement. If you have a METAR sequence containing, "SCT015 BKN032" you're still good for a visual approach at this airport since the first cloud layer constituting a ceiling is at 3,200 feet. Remember in such conditions that aircraft conducting Visual Approaches may have to deviate around cloud to keep the airport in sight, but in any case must remain clear of clouds.
Another requirement is that the aircraft must report the field in sight if he is the number one IFR aircraft. With a Visual Approach, as soon as the pilot reports the field in sight, ATC may clear him for a Visual Approach, regardless of whether the pilot asked for a one. A pilot has the right to refuse any clearance and may still wish to conduct an instrument procedure, as is often the case when a pilot is unfamiliar with the airport he is approaching. Multiple Visual Approaches are possible, unlike Contact Approaches. Successive aircraft must report seeing their traffic rather than the airport, and must be instructed to follow the preceding aircraft if they'll use the same runway, or be instructed to maintain visual separation from the preceding aircraft if they are to use different runways. In either of these cases, acceptance of the Visual Approach clearance by the pilot of the second and subsequent arrivals means that the pilot agrees to maintain his own spacing from preceding aircraft, including consideration of wake turbulence separation if appropriate. As with Contact Approaches, pilots conducting Visual Approaches must also maintain their own separation from Class F airspace near their route of flight and adhere to any noise abatement procedures in effect.
A Visual Approach is not an instrument approach and therefore has no missed approach segment. If an aircraft on a visual approach must go around for whatever reason, the pilot is expected to remain in visual conditions and complete a landing as soon as practicable. At controlled airports, the pilot will receive further direction from the tower controller. At uncontrolled airports, it is up to the pilot to determine the best course of action, keeping in mind the positions and intentions of other aircraft operating at or near the airport.
In both the Visual and the Contact Approaches, the IFR aircraft, as with any other IFR approach, establishes no priority over VFR aircraft that may be operating near the destination airport. Hence, they may be required to maneuver themselves around these aircraft as well. ATC is not responsible at uncontrolled airports for separation from or sequencing with VFR aircraft. Receiving a Visual Approach clearance or a Contact Approach clearance and being told you're number one only really applies to other IFR aircraft. At controlled airports, an IFR aircraft will be sequenced normally with the other aircraft operating near the field, VFR or IFR.
As mentioned earlier, pilots on either a Visual or a Contact approach must maintain their own separation from Class F airspace and must adhere to any noise abatement procedures for the area where the flight will operate.
Another common feature these approaches have is that neither is considered a legal option when the pilot is in receipt of a clearance for "an approach". If ATC says something like, "Air Canada 123 is cleared to the Fredericton airport for an approach," the pilot has the option of doing any published instrument approach procedure by any transition (including DME arcs, straight-ins from fixes with published transitions, full procedure, etc), but this clearance does not include Visual or Contact approaches. All a pilot needs to do is ask for approval. The odds are that if ATC is clearing a pilot unrestricted like that, he probably has little reason to refuse a Contact or Visual approach if the weather criteria for either can be met.
So while both approaches require the pilot to look out the window, there
are other similarities, but many differences. As with any clearance, the
pilot may refuse it, or request further direction at any time. In any situation
it's better to question a clearance than accept it without fully understanding
what is expected.