Today was supposed to be soft field take-off and landing (either snow/slush on a paved runway or a soft grass runway). Due to a medium but gusty cross-wind, we mostly worked on cross-wind landings.

Soft field take-offs are a little different than normal take-offs, but nothing horrible. In a normal take-off, you taxi from the run-up area (generally, the big slab of pavement at the end of the taxiway, right before the runway) at a slow speed (since it’s almost all turning), line up with the runway centerline, stop for a second to double check instruments one last time (since one should know the runway heading, it’s a good time to sanity check the directional gyro* one last time), run the throttle up to full (for a fixed-pitch prop, anyway), pull back on the stick when rotation speed is reached, feel the wheels leave the ground, climb with an airspeed of V_y (or V_x if there is an obstacle to clear), and off you go. For soft-field take-offs, it’s a bit different. Because the wheels may sink into the mush / ground, the taxi speed is slightly higher and there is no pausing in the transition from taxi to take-off — you just run up the throttle and go. For a tricycle gear aircraft, the elevator is held back all the way from the start, so that the front wheel almost instantly comes off the ground. The elevator pressure is released slowly as speed increases, keeping the front wheel off the ground, but keeping the nose down enough that the tail doesn’t slam into the ground. The plane will take off before stall speed due to ground effects, and the plane is held in ground effect until normal rotation speed is obtained. The rest of the takeoff (reaching V_x and all that) is basically the same as a normal takeoff.

Soft field landings are very different than normal landings. In a Cessna 150, a normal landing has an approach angle of at least 3 degrees, usually more (since one usually flies a C-150 in a tight pattern, as the thing can practically descend vertically for a landing, compared to other planes). With soft field landings, one comes in on the shallow end of things (a bit under the standard 3 degree approach angle) and a bit short of the runway (not much). When close to the ground, the plane is “pulled” onto the runway, using more power than normal to land the plane at a shallow descent angle. The shallow descent angle reduces the impact pressure at touchdown, reducing the drag instantly added by the wheels. Because of the shallow approach, soft field landings are pretty difficult to learn in a cross-wind when normal cross-wind landings are still a bit of a challenge. So for most of the flight, we worked on normal cross-wind landings. I did better, but still need a lot more work before I’m really comfortable. I think I’m to the point where Willis is confident in my ability to land safely, but would prefer I be a bit more refined in the effort.

*The Directional Gyro (aka Heading Indicator) is a gyroscopic instrument that gives a directional heading similar to a compass. Unlike a compass, it only provides change of heading indication — it only gives an accurate heading indication if it is aligned with a real compass heading at some point. The advantage of the DG over a real compass is that the readings are stable and accurate in a turn (unlike a compass which is nearly unreadable in turbulence, as it bounces around, and can give false readings when in a turn).