Ratty's Ramblings - Slow Flight

By Ian Radcliffe

I've been doing this flightsim thing a long time. I got started in 1984, with subLOGIC Flight Simulator II for the Commodore 64. Crude as it seems now, it captured perfectly the Piper Cherokee 180 I knew so well, and I was hooked. Since then, sims have come a long way. From a little piece of Illinois, we now have an entire planet to explore, with accurate topography, real-world weather, air traffic and ATC, and incredibly realistic aircraft.

On the day I got my pilot's license, my chief flight instructor told me: "Congratulations. You now have a license to learn." I took that to heart, and carried that attitude over to flight simulation, so that my last 35 years of simming have been not only a heck of a lot of fun but also an ongoing exploration of the intricacies of flight. I've learned a lot; perhaps some of what I've discovered can make the simming experience even richer for you.

Flying Slow

Flying is mostly about going fast. You have to reach almost highway speeds to get even a small aircraft off the ground. But there are occasions when being able to fly slowly is desirable. It can allow you to adjust spacing on approach to avoid a go-around; and with all the fantastic scenery we have nowadays it's great for sightseeing. The most obvious case, of course, is when landing. Recently, one aviation writer suggested that excess speed was to blame in two-thirds of real-world general aviation landing accidents in the US. I'm not surprised; I've sat at the approach end of the St. Maarten runway on Steam multiplayer and watched the arrivals.

Landing at or near the aircraft's slowest speed has a number of advantages. It's safer, means less wear on the gear and brakes, eliminates bounces and, perhaps most importantly in a simulation, minimizes the landing roll. Skillful slow flying allows you to fly the airplane all the way down to the runway and turn your arrivals into touchdowns.

So I wonder why more people don't fly more slowly. Is it that there's something unnerving about the low end of the speed range? After all, there lie the dreaded stall, and the spin. We treat them as things to be avoided rather than mastered.

Slow flying was one of the most enjoyable parts of my flight training. Back in the day we did actual stalls and actual spins so, with those out of the way, stooging about at the low end of the envelope was not the unnerving exercise it might otherwise have been. Experiencing stalls taught me to recognize and avoid them, confident that even if I did stall I could recover.

When you get a new airplane, it's good practice to perform a familiarization flight. During that flight, it's worth getting to know the aircraft's slow-flying characteristics and experiment with combinations of flaps, power and gear. But first, since we are blessed with the ideal device with which to explore stall behavior, let's go fall out of the sky a few times to get stalls out of the way.

Briefly: if you increase the angle between the wing and the airflow (the angle of attack) beyond a certain point, the otherwise smooth flow is disrupted and the wing stops producing lift. The plane falls out of the sky. How it falls varies from type to type, and even between individual airplanes of the same type. The appropriate aircraft for the exercise? Anything you like, but if you haven't stalled an airplane before, I'd recommend something in the Cessna 172 class. I'll be speaking at that level; if you're flying a 747 your experience may vary.

Climb to 5,000 feet above ground level and establish the airplane in level flight at a low power setting. Once you're established, retard the throttle slowly while easing back on the stick. Maintain your altitude by checking the vertical speed indicator.

As the plane slows, keep the wings level by applying opposite RUDDER; lowering the aileron to lift a wing increases the wing's angle of attack and can induce a premature stall or spin.

Reduce the throttle to idle, and keep back pressure on the stick until it's all the way back. With luck, depending on what you're flying, before the actual stall you'll experience gentle buffeting and/or the stall warning will beep/light up. Spare a glance at the airspeed indicator; that's a good number to know.

Now, the exciting bit.

There are a few airplanes that at this point will enter a stable, nose high, parachute-like descent, usually because they have leading edge slats that help maintain a smooth airflow over the wing, or because the elevator travel is deliberately limited to preclude reaching a stalling angle of attack. Most aircraft will drop their noses, with varying degrees of enthusiasm. At the far end of the spectrum, you might see violent pitch change or a dramatic snap roll.

After the plane has stalled, the first thing to do is stop pulling on the stick; release the back pressure on the stick, even push forward if the plane is reluctant to exit the stall. Then apply power and pull back carefully on the stick; pulling too hard or too soon can cause a secondary stall. Make sure that you don't hit redline RPM, or overspeed the airplane. Climb back up and do it again.

If you finished up in a spin, all is not lost. Release the back pressure, then figure out which way you're going round and apply opposite rudder until the rotation stops. Then recover as from a straight ahead stall.

There are some caveats to remember when flying slow. As already mentioned, use opposite rudder to pick up a wing that drops. The controls become sloppy, so expect to make larger control movements than usual. Variable or gusty winds are a consideration when judging how close to the stall you should go. Turns and power settings change the situation; in many aircraft a power-on stall is a very different experience from the benign nod you get with power at idle.

After you get comfortable with stalls in a clean configuration, experiment with various combinations of gear and flaps. When you're comfortable with flying on the edge of a stall with gear and flaps extended you're ready to take on those short strips you've been avoiding.

Ratty's Rambles

For a couple of years I've been coming up with flight plans for our group of weekend fliers. We're generally in GA aircraft or warbirds, and the flights are timed at about two hours apiece.

Here's an interesting one. I happened across one of the longest and deepest river valleys in Europe, cut by the river Tara in northern Montenegro, one of those parts of the world most of us probably never go. If you're into canyon running, this one is a beaut. Or you can fly the route at altitude and take in some spectacular scenery. At 214 nautical miles, it takes about an hour and a half in a single-engine retractable.

Take off from Podgorica, LYPG, capital city of Montenegro, and follow the valley of the Moraca river northwards about 25 miles to where the valley divides. Turn right to 034 degrees and fly to the NDB, and town, of Mojkovak.

From Mojkovak, a heading of 293 will take you to the mouth of the Tara river valley. Follow the valley northwest, and on to Sarajevo in Bosnia & Herzegovina. From Sarajevo, fly heading 236 for 19 miles to Lake Jablanica and the town of Konjic. Turn left to 163 and, after 68 miles, land at Dubrovnik, Croatia, LDDU.

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