Sunday, August 13, 2006

Faking It

KRAMER: You know, I faked it.

JERRY: (confused) What?!

KRAMER: Yeah.

JERRY: You faked it? Why would you do that?

KRAMER: Well you know, if it's enough already and I just wanna get some sleep.
Instrument trainees spend a lot of time executing instrument approach procedures. In fact, it's safe to say that most soon-to-be or newly-minted instrument pilots become a little fixated on flying approaches. This is normal since 1) you want to keep your skills sharp and 2) you need to fly a certain number of approaches to maintain your instrument currency. So it's easy to see why GA pilots may not use the visual approach that often. And when a procedure is not used very often, important details behind the procedure can be forgotten.

A visual approach is not faking it exactly, but it can certainly save you time by providing a more direct route to the airport. This can be a big help if you're running late, the weather is deteriorating, or it's enough already and you just wanna get some sleep. That's why I always try to facilitate at least a few visual approaches for instrument rating candidates during their training. So what is a visual approach, when can you ask for it, when can ATC assign it, and what are the requirements and responsibilities?

First, let's start with the weather conditions. To be cleared for a visual approach, your destination airport must be reporting at least 3 statute miles visibility and a ceiling of 1000 feet or greater. A visual approach is an IFR procedure, conducted under IFR in visual meteorological conditions. A visual approach authorizes you to proceed visually to the airport, but you must remain clear of clouds and the cloud clearance requirements of 14 CFR 91.155 do not apply.

The AIM says that "ATC may authorize this type approach when it will be operationally beneficial". Translation? Visual approaches speed things up because if you report both the airport and any preceding traffic in sight, you become responsible for maintaining a safe approach interval and for avoiding wake turbulence once you are cleared for a visual approach.

Since a visual approach is not an instrument approach procedure, there is no missed approach procedure. If you lose sight of the airport or the traffic you're to follow and have to abandon the visual approach, ATC will give you instructions and an additional clearance. If you're flying into a non-towered airport and you have to go around, stay clear of clouds and contact the approach controller as soon as possible.

When the appropriate weather conditions are reported, ATC will often tell you "expect a visual approach." When a controller is ready to give you a visual approach clearance, they will usually say something like:
Barnburner 123, the San Jose airport is 12 o'clock and 15 miles, report the field in sight."
or
Barnburner 123, traffic you are following is an Airbus 320 at your 10 o'clock and 5 miles, report the traffic in sight."

Remember that most controllers (tower controllers excepted) do not have windows and cannot see the weather conditions. If you are not comfortable with a visual approach and want a full-blown instrument approach procedure, it is your right and you should inform ATC as early as possible of your preference. If you're in a hurry and the weather is good, you can usually expedite a visual approach clearance by reporting the field in sight:
Barnburner 123 has Oakland in sight, when it helps.
Barnburner 123, cross the Oakland 6 DME at or above 2000 feet, cleared visual approach 27 left.

A visual approach clearance can be given in some pretty crummy weather conditions, so don't report the field in sight until you are sure you see it. Once you are cleared, you basically fly on your own navigation to the airport. Unless ATC has given you crossing restrictions, you determine what altitudes you want to fly and when you want to start your descent. If it is night and the weather is not so good, the risks increase. But there are things you can do to reduce the risks.

When flying into an unfamiliar airport, especially at night, it's easier and safer to just ask for an instrument approach procedure. Fly the procedure as published and you'll have obstruction clearance.

If you're familiar with the airport and you know the unpublished Minimum Vectoring Altitudes that the controllers use, don't go below those altitudes. If you don't know the MVA for the area you're flying through on a visual approach, you can always ask ATC.

Many GA aircraft are now equipped with GPS units that provide terrain and obstacle data. Most all of the newer hand-held aviation GPS receivers also have terrain and obstacle features. Either way you slice it, this can be valuable information. In G1000-equipped aircraft, I recommend configuring the inset map on the primary flight display to display terrain. That way, if you fly too close to something solid, you'll start to see yellow and red displayed in that little inset map.

If there is an instrument approach to the runway, have it out and refer to it. Tune the appropriate navigational aids or, if it is a GPS approach, load and activate the approach. This is especially important if you're not that familiar with the airport. Even if you are familiar with the area, the longer you fly the more all runways start to look the same. More than one pilot has inadvertently landed at the right airport on the wrong runway or at the wrong airport altogether.

Don't forget the visual approach. It's an important and handy tool to have and can get you home faster if you manage the risks.

6 comments:

The Big Pilot said...

A great post and reminder. Sometimes, youi make me want to go back to instructing. Then I see my grey hair and content myself with reading your blog. :)

Rick said...

Thanks for all the great info on your blog. I just passed my IFR knowledge test and have taken two instructional flights toward the IFR rating. Your blog is very interesting and informative for someone in my situation.

While studying for the knowledge test, I was confused about the need for both a visual approach and a contact approach. The contact approach does not require as must visibility or ceiling.

In practice, do pilots request contact approaches? What are the circumstances under which you would use a contact approach?

John said...

Big Pilot,

Gray hair, eh? Sounds like you at least you still have some hair!

;-)


Rick,

I like to think of a contact approach as Special IFR. For a contact approach you need 1sm visibility and be able to remain clear of clouds. Your destination airport must also have an instrument approach and your aircraft must be equipped to fly that approach.

Another difference is that ATC cannot assign you a contact approach - you must be crazy enough to ask for it.

I believe contact approaches to be pretty darn dangerous. You need to be very, very familiar with the terrain and landmarks to fly one safely.

I'd have to be pretty motivated to use a contact approach - like an abnormal engine indication right after takeoff, rapidly deteriorating weather, or something. When I was a freight dog, my employer did not allow us to fly contact approaches.

If it sounds like I'm painting a dire picture regarding contact approaches, well, I am. They are dangerous with a capital D.

Ron said...

Here's a tip that can really make visual approaches, contact approaches, circling approaches, and pretty much any approach at night a little easier: turn down the brightness of the screens and/or cockpit lighting to the minimum necessary to read the instrumentation.

With the lights up too high inside the cockpit, it gets really hard to see anything outside. Students always seem impressed by the change in outside viz once the cockpit lighting is down to a dull roar.

BTW, I *love* Seinfeld. Nice reference!

Colin Summers said...

http://www.flyingsummers.com/2006/06/24/terrain/

Since you recommend turning on the terrain awareness, and since I was fairly recently terrified by messages from same, can you address this? Do YOU actually fly around in the yellow comfortably?

Do you talk to your G1000 students about the fact that the altitudes in the terrain database are GPS and their reported altitude is off the pressure-sensitive altimeter, not the math-based-error-sensitive GPS?

John said...

Colin,

Try using the terrain display in the inset map, not the MFD map, and keep the TOPO view active in the MFD map. The terrain view can be a bit overwhelming on the large display.

I read your post and it sounds like you hadn't used the terrain feature much prior to your night flight across the desert. The terrain display does take some getting used to. Sitting on the ground before takeoff with the terrain feature turned on, everything will appear as red. After takeoff, everything will probably appear as yellow for a time. Once you reach a higher altitude, the display becomes more useful.

There are limitations in the terrain feature, but the resolution is most likely within a few hundred feet, which is good enough for a warning system. Remember, too, that some systems have an obstacle database and others do not.

Experiment with the terrain feature some more. And in answer to your question, I'm not bothered by flying around in the yellow areas, as long as I can clearly see the terrain. Heck, we do this sort of thing every time we takeoff and land, but we don't realize it if we don't have a terrain display.

All tools have limitations ...