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From the Editor

The Impossible Turn Revisited Again

An update to last month’s column

Story and photos by Patrick Panzera, EAA 555743, ppanzera@eaa.org

Pat Panzerz

In last month’s editorial I wrote of my personal experience with “the impossible turn.” As one might expect, I received a lot of commentary from the readers, most through Facebook (now that our articles are linked to it), but I also received several directly through e-mail. Overall the comments were complimentary, and I truly appreciate it. But some made a few good points that I missed which I’d like to share with you now.

The impossible turn: “A 500 feet/minute rate of descent coupled with a ‘standard rate’ turn (2 minutes to complete a 360-degree turn) means that you need at least 500 feet of distance between you and the ground to complete a 180-degree turn. So unless you have a minimum 500 feet above ground level (AGL), the turn is ‘impossible.’ There are other issues here such as wind speed and direction, needing additional altitude to realign with the runway, etc.” 

Although I tried to hedge against it in the opening of my article last month (quoted above), where I gave an overly simple example of what many consider to be the “impossible turn,” several took me to task saying that I neglected to account for realigning with the runway, requiring additional time aloft, while in a turn. It seems that my statement “There are other issues here such as wind speed and direction, needing additional altitude to realign with the runway, etc.” wasn’t sufficient, so I’d like to address that now.

Yes, you’ll need more time to realign with the runway, if that’s your intent. However, this is an emergency situation where landing isn’t optional. Any place you can put the plane where people or property around you isn’t harmed is fair game in my opinion. So why not consider the parallel taxiway? Or even the dirt adjacent to the runway? Or even a crosswind runway (if available) as one reader pointed out to me? So not only is it a good idea to practice the turn in every plane you fly, it’s a good idea to decide exactly how you’d execute it for each runway from which you’re departing.

One person wrote to me to ask about the landing traffic behind the person making the impossible turn. What do you do when you’ve made the turn, all nicely aligned, and someone is departing or landing straight at you?

I was taught that when departing, wait on the ground until the plane in front of me is far enough away from the departure end that he couldn’t make it back in the event of an emergency (even if he wanted to) and to keep an eye on him throughout my departure. 

Although not specifically taught, I use a version of that “common sense” lesson when I land behind a departing plane. 

One thing people don’t consider when talking about the impossible turn is that even if I can’t realign with the runway, there are plenty of other options on the airport, beginning with (as already mentioned) the parallel taxiway, parallel runway, or even crossing runways. Not every airport has a single strip without any taxiway or tie-down area, but even if they do, in many cases, the airport environment is a better place to crash than on the other side of the fence.

In my case, from my home airport, the options are:

1) turn back
2) land on the freeway
3) land on a busy street in a commercial district
4) land on a residential street
5) crash on a house.

All the options except the first involve other people who didn’t accept the assumed risk I took when I decided to begin that flight that day, and I believe it’s my duty not to involve them, even at my own expense. 

At one time, I was on a right crosswind departure from three-two when my engine in the rental plane started running rough. I knew I could safely make it back to one-four with no problem but wasn’t sure if I could nurse it all the way back to three-two. But I also knew there was landing traffic behind me. So I declared,aligned, and started an aggressive slip to use as little of the runway as possible. 

The landing pilot, who had plenty of time and opportunity to go around, was continuing his approach. I made the radio call again, realizing that for whatever reason, he may not hear me again. So I made the decision that if it started to get ugly looking, I’d sidestep to the empty taxiway. As it played out, he saw me and yelled into the mic, “Get out of the way!” and stopped short as I was stopping short and turning off. We have a 5,000-foot strip; I was already set up to get off at the first exit (1,500 feet), so all in all it was no real factor. But his seat had to be surgically removed.

Turns out his hearing aid was turned off. 
 
Glider Time Is Great Engine-Out Practice
I received the following:

“Good article! There’s nothing like trying things out yourself to see how they work in real life. I came to powered flying after several years flying hang gliders, so I enjoyed playing with gliding flight in the rental 150s and 152s. It’s fun to set the throttle just high enough to give a gliderlike sink rate at best glide and then try to soar. Also, having practically memorized Stick and Rudder, power-off approaches seemed like a normal thing to practice. It’s very satisfying to go to idle on a close downwind and cross the threshold on speed and altitude. Most pilots without glider experience panic when the engine dies. Power-off training can be a real confidence-builder.”

Consider the Climb
One reader commented:

“There are some airframes that, due to slow climb rate, high glide speed, or short runway, are not suitable for such a turn, and thus it is better to land them in the direction of takeoff. An example is the Piper Arrow on a 3,000-foot runway. One needs about 800 feet of altitude for the Arrow’s turnaround, and with its slow climb it would be too far from the runway [to ever make it back] when 800 feet is achieved. On a 10,000-foot runway it would do fine.”

Another one wrote:

“It may take me 700 feet to get turned around from 800 feet AGL, but that is not going to do me any good if I have 100-foot trees on the approach path.”

Another good comment from a reader:

“I have for years taught in multiengine aircraft while in the military and can tell you from experience the most experienced aviator will do some of the dumbest things when you pull an engineon him or her when they aren’t expecting it. As you know, statistics show that the odds are in the grim reaper’s favor when trying to perform the impossible turn. The statistics are in my favor when I fly it into a rock pile while maintaining control all the way till impact, and then trying to maintain as much control as possible till the aircraft comes to a stop. I tell my students that, “Once the engine quits, it belongs to the insurance company, and it is their problem, not yours. You just need to get your butt on the ground as safe as possible.” 

A few readers found fault with my practice session, where I leveled the plane at 5,000 feet and trimmed for 70 knots before executing my power-off turns. They suggested that I should have had it in a normal departure climb, then wait two seconds (or more – some suggested upwards of 10 seconds) after pulling the throttle for the “Oh my!” factor (cleaned up for our G-rated audience). This would be the closest to replicating an engine failure on departure.

But in every case, the consensus was unanimous: If you’re going to ever consider making that turn, make sure you’ve practiced it. Several people wrote (in support of practice) and said that if a pilot isn’t comfortable making the turn at altitude, he won’t be able to pull it off close to the ground.

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