Technique: Field conditions

However, if that green grass is not rooted in firm soil, your touchdown might be a pain rather than a pleasure. It could throw up a muddy mess under your fuselage, provide an opportunity for your airplane to stay grounded awhile, or even send you for a loop—a ground loop. So, it’s best to know the condition of that sod before landing.

Local knowledge

Typical advice on this topic often suggests calling the flight briefer and asking about soft field or closed field notams, but my inclination is to go straight to the source. Call the FBO or airport manager, or the owner if it’s a private field—someone whose feet have trod that airfield within the past few hours. They’ll give you the actual current conditions and advice that no briefer could provide. For example, my favorite grass airstrip is built on a hill, with the top half of the field flat and the rest on a slope. If you called the airport manager there after a good rain you might be advised to land on the uphill runway and then taxi toward the hangars, areas that are usually firm ground no matter the amount of rain. However, the flat areas may be covered by puddles and excessive mud if the recent rain was intense.

Call the FBO or airport manager, or the owner if it’s a private field—someone whose feet have trod that airfield within the past few hours.That doesn’t mean that you shouldn’t check for notams before flying to another airport, especially one far away. It’s essential to call the briefer (1-800-WXBRIEF) for the forecast and notams along your route, and especially for your destination (and alternate) airport. But, for there to be a notam alerting pilots to a muddy field, someone with the authority to create a notam must have called it in. Briefers have a list of authorized people at each airport; not any Joe can create one.

However, the manager at my favorite grass airstrip told me she rarely, if ever, calls in a “muddy field” notam. She recommends that everyone communicate on the unicom frequency before landing to determine the field conditions. Last winter, I was making a practice approach to her field and broadcasting my position when she radioed, “You might not want to land here, it’s pretty soft.”

Weather briefers are a good source for current information and future outlooks, but they lack the history of past weather events. I called a briefer and asked, “I know you can give me the current conditions at an airport, but can you tell me how long it’s been raining and how much?” Nope, he could tell me if it was “raining lightly, moderately, or heavily for the past few hours,” but he didn’t have data on whether the field received eight inches of rain over recent days—or none at all.

However, you can consult online resources for weather history. The Weather Underground website has an easy-to-use historical weather function. Go to wunderground.com/history and type in the nearest city to where you want to land. It will give you all the historic weather data, by the day, week, or month.

Once airborne, radio the FBO at your destination, if there is one, as early as conditions—altitude and the strength of your radio—allow. If you hear a pilot who has just landed, call and ask, “How’s the turf down there?”

Take a close look

If you’ve arrived with no clue about the condition of the field, well, you probably shouldn’t be there. If you’re determined to land, first make a low pass down the runway and have a look. If it looks dry and is covered with healthy grass, it’ll probably be firm enough for most small airplanes. If it looks wet, and there are no puddles or muddy areas, you might want to test the ground with your tires. Perform this maneuver only if you are confident in your abilities; otherwise find a paved runway. Keep some power on during your landing flare and let the tires touch down gently, then immediately add power to go around. If you feel the tires sink in or drag, or if a lot of water and mud spray up, it may be best to use your alternate airport. You planned for one, right?

The general rule for soft-field landings is to touch down at the slowest speed possible and gently transition the weight from the wings to the wheels.If it seems firm, use the soft-field landing techniques detailed in your aircraft’s POH, which you reviewed before takeoff, right? Pull out the book again before arrival if you need to refresh your memory on the procedures.

The general rule for soft-field landings is to touch down at the slowest speed possible and gently transition the weight from the wings to the wheels. Have active feet on the rudder pedals and keep the nose straight. Wet grass can be as slippery as ice to the smooth tires of an airplane traveling at 55 mph or more.

Once settled on the Earth and slowed to taxi speed, keep the airplane rolling. Brakes shouldn’t be needed as the soft ground and grass will provide plenty of drag, possibly too much. Often, a fair amount of power is needed to keep the airplane moving. For nosewheel airplanes, try to hold the nosewheel off as much as possible to prevent it from digging in. Keep moving, get away from the runway, and find firm ground to tie down. Remember, you’ll have to taxi from this parking spot later.

You gotta get out, too

Now that you’ve made a good landing, your next concern may be whether it’s too mushy to take off. Walk over the ground and check for soft spots, ruts, and holes. Investigate any places where the color of the grass is different, which could indicate an area where water has been flowing—and, therefore, soft ground. Be certain to allow an extra margin for the takeoff roll, well above what the pilot’s operating handbook recommends for a soft-field takeoff.

There’s no official definition of “soft.” There’s soggy grass that will slow your acceleration significantly and there’s muddy ground so sticky you’ll never reach flying speed. You don’t want to be approaching the end of the field at 40 mph with full power. Review the soft-field takeoff procedures for your aircraft and have a plan for when to quit.

Not just dirty, dangerous

Muddy fields have bent many an airplane and bruised as many pilots. That placid puddle could be hiding a deep hole—one that could snap off a landing gear, pop a tire, and send you careening across the field. Wet fields may be as dangerous as they are dirty. That’s why local and current knowledge is so important.

When planning a flight to a grass field, especially during the rainy season, you must always have a nearby alternate with pavement. It’s better to take a taxi the last few miles to your destination than have your aircraft stuck in the mire—or end up with the oily, and now muddy, side up.