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Flying in IMC: Nothing Like the Real Thing (Audio Series from IFR Refresher)

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The Real Deal

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Having an instrument rating doesn't mean that you have to fly in the clouds-it just means that you can, legally. In fact, the FAA doesn't require a pilot to have any experience whatsoever flying in actual IMC in order to qualify for, or maintain, an instrument rating. An instrument rated pilot could go his or her entire flying career flying the requisite six approaches every six months using a view-limiting device in VMC with safety pilot or instructor watching for traffic.

There's certainly nothing wrong with an instrument-rated pilot who never flies in actual IMC, as long as the pilot adjusts his or her personal flying minimums accordingly. After all, there are plenty of perks to be reaped from the instrument rating besides the ability to fly through clouds, not the least of which is a "free pass" through Class B airspace and the comfort and increased safety that comes from being in constant contact with air traffic controllers, especially on a lonely, moonless night. In some parts of the country, like the desert Southwest, it may be near impossible to find any clouds to fly through. But for the majority of us who live in places where haze, fog and clouds are a fact of life, being comfortable flying through these weather phenomena makes the instrument rating much more satisfying to achieve and useful to maintain.

In my October 2008 "Ground School" column in IFR Refresher, I related an experience that I recently had with a student flying in actual IMC. The student told me after we landed that flying in the clouds was fun and exciting, but also humbling. The stakes are higher when you can't peek outside and see the horizon.

A few weeks later I invited my friend and fellow flight instructor Will Russell to join me on a flight in actual IMC. We documented the flight in our flying club's Cessna 172 by taking photos and recording cockpit voice communications, so that IFR Refresher readers might experience what it's like to fly IFR on a cloudy day in busy airspace. For those of you who have been flying IFR for years and are comfortable flying in IMC, we hope that this presentation will provide an opportunity for you to reflect on your personal flying habits and experiences, and whether there are any specific skills you need to work on. For those of you who are new to instrument flying or have never flown through a cloud before, we hope that you will consider giving it a try sometime with a qualified, experienced instructor or instrument pilot.

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Before Takeoff

I filed an IFR flight plan from our home base, Montgomery County Airpark in Gaithersburg, Maryland to Culpeper Regional Airport in Culpeper, Virginia, a straight-line distance of 50.4 miles.

The weather forecast for the day called for scattered to broken clouds at about 2,000 feet throughout the area, with a slight chance of precipitation throughout the day but no thunderstorms. Surface visibility was forecast to be better than 6 miles throughout the area. The winds aloft forecast indicated we could expect about a 15-knot headwind on the way to Culpeper, which translated to an estimated flight time of one hour including takeoff, climb, vectors along the route, approach and landing.

The Montgomery County AWOS reported winds from 220 at 6 knots, visibility 10 miles, broken clouds at 1,700 feet with an overcast ceiling at 2,200 feet, temperature 21C, dew point 18C, and altimeter 30.19. With winds generally out of the south-southwest, we anticipated flying the RNAV (GPS) Rwy 22 approach at Culpeper.

Will contacted Potomac Clearance Delivery for our IFR clearance, which would first take us northeast toward the Westminster VORTAC and then radar vectors to join V214 toward Martinsburg, West Virginia. However, experience told us that the more likely scenario was some amended route after departure.

Click here to listen (MP3 file).

Departure and Climb

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We were released for departure at 10:30 a.m. with Will at the controls as pilot in command of N52126. As he climbed out of the Gaithersburg traffic pattern to our initial assigned altitude of 3,000 feet, our visual scan of the instruments intensified as we prepared to enter a sea of white and gray marshmallow fluff.

Click here to listen (MP3 file).

Cruise and Approach Briefing

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After the Potomac Approach controller identified us on radar, we were immediately given vectors to the northwest and a climb to 4,000 feet.

Click here to listen (MP3 file).

A few minutes and a frequency change later, a different and very busy controller told us to fly direct to TICON intersection, and then vectored us to the southwest. He asked us to tell him the type of approach we wanted to fly into Culpeper and to advise when we had the weather there. Listening to the AWOS provided its own unique challenges.

Click here to listen (MP3 file).

Accurate and timely radio communications are critical to the safe and smooth flow of IFR traffic, especially in congested Class B airspace. Listen to what happens when two experienced pilots do their best to comply with the demands of a busy and clearly agitated air traffic controller, who makes a simple mistake and does not realize that he has done so. In high-workload, tense situations such as this, it is critical for the pilot to maintain situational awareness at all times while monitoring the flight instruments in IMC. Will made extensive use of our aircraft's single-axis autopilot to initiate turns and maintain assigned headings throughout the flight.

Click here to listen (MP3 file).

Will and I were relieved when we were handed off to yet another controller, who would eventually issue our approach clearance into Culpeper. As we continued flying south, it became apparent that this controller had his work cut out for him to vector us to the right (to the west) once we passed Washington Dulles International Airport.

Click here to listen (MP3 file).

Approach and Landing

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Once we were south of Dulles, the controller descended us to 3,000 feet, the initial altitude for the GPS approach into Culpeper. He had to vector us around other traffic that was headed for the Manassas Regional Airport in Manassas, Virginia. But since we were in and out of the clouds, we knew that we probably would not be able to establish or maintain visual separation with them.

Click here to listen to Part 1 and click here to listen to Part 2 (MP3 files).

As we got closer to Culpeper, another challenge presented itself. An aircraft departed Culpeper VFR with the intention of landing at Manassas. It seemed as though he wanted to pick up an instrument clearance in the air, but also had a VFR ADIZ flight plan on file, which is required because Manassas is located inside the Washington, D.C. ADIZ. The controller was not able to see the VFR aircraft on radar, so in order to maintain separation between us he asked us to climb back up to 4,000 feet.

Click here to listen (MP3 file).

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Once the controller sorted out the situation with the VFR aircraft going into Manassas, he instructed us to descend back down to 3,000 feet. He then issued us a clearance to begin the GPS approach, which Will had already loaded into the Garmin GNS430W. The controller advised us that there would be a King Air behind us on the approach, and subtly hinted that he'd appreciate it if we could cancel our IFR clearance in the air with him prior to landing. Will responded that he would cancel "as soon as it's practical," meaning as soon as we were able to without sacrificing safety. Remember that canceling an instrument clearance in the air offers little benefit to the pilot flying the approach, although it may allow the controller to sequence the next aircraft in the queue earlier than if the pilot on the approach waits until he lands to cancel the clearance.

Click here to listen (MP3 file).

Crossing the initial approach fix (DOYAT) inbound Will began a descent as the GPS-based glide slope started to show signs of life.

Click here to listen (MP3 file).

The GNS430W indicated "LPV" which meant the glide slope was available, so our minimum descent altitude on this approach would be 657 feet after crossing the final approach fix (CALPE) at 2,200 feet.

Click here to listen (MP3 file).

With the pre-landing checklist completed, it was time for Will to land the airplane. Listen to how Will ignores the request of the King Air pilot who is waiting for us to cancel so that the controller can clear him for the approach.

Click here to listen (MP3 file).

We shut down the engine at Culpeper at 11:45 a.m., exactly one hour and 15 minutes after we took off from Gaithersburg. This flight was just one example of the many challenges that we as instrument pilots face when flying through the clouds. We hope you enjoyed riding along with us.


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