A couple of weeks ago we wrote about skids and slips, and the implications of a skidding turn onto final. We found a great article from Boldmethod discussing this topic further and thought it would be great to share. So without any further ado, let's here it from the experts
Overshooting your base-to-final turn can be a problem. Getting yourself back on course can be deadly. Here's how you can stay safe.
The Base-To-Final Turn When you're in the traffic pattern, your base-to-final turn is the most important, and potentially the most dangerous one that you make. You need to pay special attention to your base turn for several reasons: 1) you're low, 2) you're slow, and 3) you have the potential of an accelerated or cross-controlled stall if you overshoot final.
Overshooting Final Overshooting final happens for several reasons - the first of which is wind. If you have a crosswind like the image below, you'll have a high groundspeed during your base leg. And the higher your groundspeed, the more bank you'll need to roll out perfectly on centerline (remember S-Turns across a road?) Another reason for overshooting final is simply mis-judging your turn rate (which, by the way, I've done more times than I care to remember). You're on your base leg, you're looking at the runway, and you simply don't start your turn in time. Next thing you know, you've blown through final, and you're lined up with the ramp and hangars on the other side of the airport. Regardless of the reason for your overshoot, what happens next is the most critical part of your traffic pattern.
Overcorrecting
Naturally, when you overshoot final, you want to correct and get yourself back on the extended centerline of the runway as quickly as possible. But herein lies the problem: the more you correct, the more danger you put yourself in. That's because you're setting yourself up for an accelerated stall, or worse yet, a cross-controlled stall.
Accelerated Stall
Your plane can stall at any airspeed, as long as it exceeds the Critical Angle-Of-Attack. This becomes a problem when you start increasing your bank angle to get yourself back on centerline. As you increase your bank, you pull back on the yoke to increase your total lift, so that you can maintain the same vertical component of lift you had previously. So as you increase bank and back pressure to get yourself back on the extended centerline, you increase the AOA on your wing. And even if your airspeed stays exactly the same, you get closer and closer to a stall. Eventually, if you bank enough and pull back enough, you'll stall. And since you're just a few hundred feet above the ground at this point of your flight, you're in a very bad situation, even if you're coordinated.
Cross-Controlled Stall
A cross-controlled stall is another recipe for disaster when you overshoot your base-to-final turn. It goes something like this: you overshoot the runway, and you start increasing your bank to get back on final. You realize that your bank is too steep, but you need to keep your airplane turning, so you decrease your bank and step on the rudder to keep your turn rate high. The problem with a cross-controlled maneuver like this is that you're skidding your plane, and if you stall, you will almost certainly enter an incipient spin. And if you start to spin this close to the ground, your chances for recovery are virtually 0%, regardless of your pilot skill. There just isn't enough altitude to recover.
Managing Your Angle-Of-Attack
All of these overshoot scenarios come back to one thing: managing your angle-of-attack to prevent a stall. One of the best tools out there to help you is an AOA indicator like Garmin's Angle Of Attack Indicator, or one of the many other AOA tools you can put in your plane. But even if you don't have access to an AOA indicator, by constantly scanning your airspeed and bank angle in the pattern, you'll be much more aware of where your plane is in the flight envelope.
The Best Option: Go Around
So what's the best option when you see yourself overshooting the runway? It's incredibly simple: just go around. Power up, pitch up, and give it another try. Trying to overcorrect and putting yourself in harm's way just isn't worth it. And after all, who doesn't mind an extra 0.1 in their logbook?
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