EAA Sport Aviation

BOB O’QUINN
Grass Landing
Grass strips extend flying enjoyment and safety
DESPITE THE FACT THAT soft-field techniques are a required part of primary
sport and private pilot training, too few pilots have ever experienced real
grass runways during their flight training.

Although most aircraft flying in and out of grass fields are conventional gear (tailwheel) aircraft, more pilots of nosewheel-type aircraft are discovering the benefits and enjoyment of grass field capability. For instance, what would feel like a good landing on a paved surface often feels like a great landing as tires softly settle into the grass. Aircraft tires last many times longer landing on grass, compared to landing on a hard surface where every touchdown is like getting hit by a high-speed belt sander.

Perhaps the most significant benefit of grass-field capability is the additional 11,000-plus potential emergency landing options that grass fields provide throughout the United States. Although most grass fields are privately owned and do not need to meet FAA requirements, they are likely better emergency options than an unfamiliar pasture that might have stumps, gopher holes, and ruts.

According to the Civil Aviation Authority (CAA), approximately one-third of reportable general aviation accidents in the United Kingdom occur at unlicensed (private) grass fields during takeoff or landing. In the United States, the National Transportation Safety Board data also indicates a similar situation. Accidents related to grass fields are often the result of inexperience and a lack of familiarity with the nuances of the grass-field environment.

Before taking advantage of grass fields, pilots need to acknowledge that the takeoff and landing distances on grass will be significantly different than on hard surfaces. They can always expect a longer takeoff roll, while landing and stopping distances will be appreciatively reduced by tall grass, rough surfaces, or uphill slopes. Conversely, a much greater stopping distance is needed after a heavy dew, frost, or rain, all of which can render aircraft brakes and steerable nose wheels and tail wheels virtually ineffective. Pilot’s operating handbook figures are based on a dry grass runway and are therefore useless for calculating distances in other situations. The CAA suggests increasing

The CAA suggests increasing wet grass landing distances by

60 percent, “like an icy surface.”

WHEEL HEIGHT

Do not land if grass is above 30 percent of wheel height.

wet grass landing distances by 60 percent,
“like an icy surface.”
Since flying in and out of grass fields
requires slightly different techniques for pilots
of nose wheel and conventional gear aircraft, it
is best to obtain dual instruction in grass-field
operations prior to attempting it alone.

The ideal grass runway would have a
firm, level surface of well-maintained
(closely mowed) grass with good drainage to
prevent standing water. There should also be
no trees, power lines, or other obstructions
nearby. However, in the real world, the grass
runway environment might have trees or
power lines on the approach ends or adja-
cent to the runway; wandering farm animals;
a runway that slopes uphill, downhill, or
both; only one side usable after a heavy rain;
a questionable runway length; or long grass.
Chances are that during grass-field transi-
tion training pilots will have to contend with
several of these irregularities. Each pilot
must set his or her own personal grass-field
limitations based on experience and skill, as
well as aircraft performance. A good one to
begin with comes from a CAA safety bro-
chure, “If the grass height is more than 30
percent of the wheel [outside diameter—top
to bottom—of the tire], it’s a no go!”
Like anything in aviation, judicious practice
can make any pilot better and safer.

Bob O’Quinn, EAA 742434, is a part-time certificated
flight instructor whose primary focus is on tailwheel
training. For links to more articles about flying on/off grass,
visit www.SportAviation.org