2011 12 short field operations part 2

Vintage Instructor THE

BY Steve Krog, CFI

Short-Field Operations, Part 2

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n part 1 on our series concerning short-field landings, we discussed two methods for making safe short-field landings. Now let’s add one more factor to the equation and look at making a short-field landing—over a 50foot obstacle!

Unless you fly from a private strip with obstacles at one or both ends, you may not have even attempted a short-field landing over a 50-foot obstacle since your sport, private, or commercial checkride eons ago.

Can you recall the last time you actually tried one?

The short-field obstacle landing is not difficult, but it does take some practice to perform this landing safely and skillfully. Practicing these landings and increasing your proficiency may be the difference between a safe uneventful landing and a bent and broken airplane when attempting a landing at someone’s private strip someday.

How many times have you read an NTSB accident report stating that while flying in VMC, the pilot attempted to land on a friend’s private airstrip? After realizing the landing was too long, the pilot attempted to “plant” the airplane and apply heavy brake action, only to find himself or herself upside down! I’ve read a number of these accident reports over the years, and with regard as to how and why it happens, it doesn’t seem to make any difference in the amount of flight time the pilot has accumulated.

32 DECEMBER 2011

When either teaching this landing or asking for it to be demonstrated during a flight review, I’ve identified three common weaknesses: • Inability to judge height.

• Inability to establish and/or maintain airspeed.

• Lack of familiarity with the airplane (i.e., comfort level).

How many times have you read an NTSB accident report stating that while flying in VMC, the pilot attempted to land on a friend’s private airstrip?

Inability to Judge Height All pilots—young or old, experienced or inexperienced—look to the sky as soon as stepping outdoors. We learned early in our training how to identify types of clouds and weather associated with each. We also learned, with a little practice, to generally judge cloud heights. How many times have you walked from your car or truck in your workplace parking lot, looked up, and mumbled, “This would be a good day to fly!”

Why is it then that when looking up we can judge cloud bases within a few feet, but when asked to demonstrate a 50-foot obstacle landing, we have no clue as to what 50 feet looks like when looking downward toward the approach end of the runway?

Over the years of my acquired experience providing primar y flight instruction, I’ve developed a method for teaching 50-foot obstacle short-field landings.

After a brief preflight discussion describing the procedures for making this type of landing, we’ll go out and put these procedures into practice. I’ll first have the student demonstrate what he or she believes to be the correct way for making this landing. Without fail, we will cross the runway threshold (where our simulated 50-foot obstacle is located) and be anywhere from 250 to 500 feet above the runway. As we initiate a go-around, I’ll ask the student to call out our altitude. Let’s say, for the sake of example, the

student calls out 1,450 feet.

While climbing out and flying the pattern, I’ll ask what the field elevation is at our airport, and the response is always 1,070 feet. Now add 50 feet and what do you get?

Unless the student is quite young and is still attending school where math is no longer taught, the answer will be 1,120 feet. That is the altitude we need to clear then. Now add an additional 50 feet to that amount for instrument lag, 1,170 feet, and that is the altitude to strive toward on the next approach.

Additionally, for the next three or four landings, I will verbally call out our altitude above the obstacle as we descend on base and final legs. This method seems to help the student better grasp how high he or she is at any given point. You might try this method yourself if you haven’t practiced an obstacle landing in a while.

Inability to Establish and/or Maintain Airspeed Up to this point most student pilots, as well as established pilots, have developed a skill level for establishing correct airspeeds for the approach and landing in their particular airplane. For the sake of discussion, let’s say the airplane we’re flying uses the following speeds: 80 mph after reducing power on downwind, 70 mph on base leg, 65 mph after turning final, and 60 mph on short final. If a student, or seasoned pilot, understands and practices “attitude flying,” these speeds will be common on every approach to land without ever having to look at the airspeed indicator.

However, throw in the 50-foot obstacle, and airspeed control wildly fluctuates. If it appears to the pilot that we’re too high, oftentimes the nose is pitched downward and our airspeed is reading 90 mph and increasing. The obstacle is cleared, but now it will take 2,500 feet of runway to get on the ground and stopped—1,500 feet more than we allowed for this maneuver. Or, if it appears that we’re too low, the nose

is pitched upward and some power is added. More often than not, the power added is enough to easily clear the obstacle, but we’re hovering dangerously close to either a stall or, at the very least, a rapid descent to the runway. In this scenario the power is then chopped, the obstacle is cleared, the landing is very short, but the airplane may not be usable again without first repairing the landing gear.

The more correct method is to stabilize the approach speed and rate of descent. Then after turning final, pick an aim point 300-500 feet beyond the approach end of the runway. Continue the stabilized approach and add or reduce power as needed to compensate for the effect of the wind. Once you can see that the 50-foot obstacle can be cleared, slowly reduce power, which will slightly increase the rate of descent. Level off and begin your flare. While doing so, simultaneously reduce your power to idle.

Upon touching down, continue to hold the yoke or control stick in the full aft position and gently apply even brake action. A few more practice landings, and you’ll soon have the short-field obstacle landing safely and skillfully mastered.

Lack of Familiarity With Your Airplane (i.e., Comfort Level) When first practicing obstacle landings, one of the fears that students express is getting the airspeed too slow and approaching a near stall. It’s a common fear, but it can easily be overcome by getting more familiar with the airplane being flown.

In part 1 of Short-Field Operations, I suggested several exercises that a pilot might do to develop a confident, safe feel for the airplane being flown. First, at a safe altitude, align your aircraft with a road (our simulated runway). Reduce the power to idle while maintaining the desired constant airspeed that you should normally use on final approach to land. Burn the nose attitude image firmly in your brain so

that you never need to look at your airspeed. Try this maneuver several times. The trim system can be a pilot’s best friend, sometimes especially when landing. Use it to help stabilize the desired attitude.

Next, do the same exercise over the road, but this time experiment by first adding and then reducing power. How much can you slow your rate of descent down when adding 200 rpm while still maintaining a constant airspeed plus 5 mph? This maneuver is especially good for developing the skills needed to make consistently safe short-field obstacle landings.

Judging altitude, controlling airspeed, and knowing your airplane are essential to being able to perform short-field obstacle landings safely. The next time you decide to go flying for fun and pleasure, challenge yourself and try the exercises I’ve mentioned.

With a little practice, you’ll be able to turn onto final, maintain a constant airspeed, and be in full control of your rate of descent. If needed, a forward slip can be established for a couple of seconds dissipating the remaining altitude, then aligning the airplane with the centerline, establishing the flare, and smoothly touching down while reducing whatever power remains.

Most of the classic airplanes we fly today need little more than 500-800 feet to land. Allowing for obstacle clearance, a distance of 1,000-1,200 feet is about average for an obstacle landing with little or no help from the wind.

Take the Challenge A pilot striving to be a better, more skilled pilot becomes a safer pilot. And isn’t that a goal for all of us who enjoy general-aviation pleasure flying?

Next time you decide to make a pleasure flight after work or on Saturday morning, challenge yourself and try a couple of simulated obstacle landings. They are both skill-enhancing as well as self-satisfying!

VINTAGE AIRPLANE 33