2/28/15
Cessna 172 – N734KU
The worst thing about stalls is the anticipation. The actual stall, and recovery is tame in comparison to what you are expecting to happen. As stated in a previous entry it is actually quite difficult to get an entry-level aircraft to stall.
As I was driving to the airport my car was getting tossed around by the wind, so I was anticipating a rough flight, if not being grounded outright. By the time I got to Twin Oaks things had calmed down a bit though, and while there was a bit of rough air getting up to altitude, we managed to find smooth flying up at 4000 feet. After the last lesson in the 150, I wanted to give the 172 a try for comparison. From the outside it doesn’t look much bigger, but the little bit of extra elbow room makes all the difference for comfort. It feels like a real airplane. Pre-flight is almost identical, except the engine cowling does not open for visibility. There is only a small access panel for access to the oil dip stick and gascolator. 4KU has the 180HP engine. While I didn’t note the climb speed, it felt quite happy to take the two of us to altitude.
Trim is a whole new concept to me, coming from helicopters. While we had the trim adjust for cruise flight, it was an on-off device and didn’t really do much in the first place. Control pressures in the R22 were very light even during the most aggressive maneuvers. I can finally see what all the fuss is about properly trimming your airplane for each flight regime. This was dramatically apparent when recovering from stalls. The most important action in recovering from a stall is to decrease back-pressure on the yoke. The first couple attempts at stall recovery I had the trim too far forward, so when I released back-pressure the nose pointed way down. We lost quite a bit of altitude before leveling out. By trimming more proactively, and being conscious of how much control inputs were actually required my stalls smoothed out to non-events after a few tries.
We practiced three flavors of stalls on this flight: power-off, power-on, and turning stalls. Power-off, and power-on are similar, although in a real emergency, they tend to occur in different phases of flight. A Power-on stall might result from an overly steep climb-out in a clean configuration. Can anyone say high DA! A power-off stall might occur during landing. For practice purposes, power-on stalls are difficult because it can be really difficult to get the darn plane to actually go slow enough to stall, without dipping into the territory of aerobatics.
Turning stalls are perhaps the most interesting, because they exhibit some counter-intuitive behavior. Due to aerodynamic effects, the outside wing of a turn actually stalls first (because it sees a higher angle of attack). This means that if you are turning to the right, a stall is going to drop the left wing. The recovery in all cases is to release-back pressure and apply rudder, not aileron, to correct developing turns. Aileron inputs can increase the angle of attack on the wings and deepen an already developed stall.
I will be taking a break from flying for a short time as I shop for a plane of my own. With luck, my next entry will be from my new training aircraft.