Vintage Instructor THE
BY DOUG STEWART
Between a rock and a hard spot In last month’s article I wrote about flying on the backside of the power curve. So just as a refresher in case you didn’t get a chance to read it, the backside of the power curve exists whenever there isn’t sufficient power to overcome the induced drag created by high angles of attack. Anytime we fly in slow flight, we are most often on the backside of the curve. In this regime, you will notice that if you increase back pressure on the stick, the houses actually get smaller rather than bigger. This is why it’s known as the area of reverse command. And of course if we continue to pull on the stick, or yoke, the airplane will reach its critical angle of attack, and if that angle is exceeded the airplane will stall. To add insult to injury, if we haven’t added sufficient right rudder to compensate for all the left-turning tendencies occurring in this attitude, when the airplane stalls, it will most likely spin. For many pilots this area of flight is rarely experienced, except on practical tests or on flight reviews. I don’t know many pilots who go out and practice flying as slowly as they can, but I personally love to go up in my PA-12 when the winds aloft are blowing at more than the stall speed of my Super Cruiser. I then pull the power back until I am just hovering in place, and chuckle to myself as I think of the terminal radar approach controllers (TRACON) wondering about what visual
22 JANUARY 2009
flight rules (VFR) aircraft is hovering at 5,500 feet. However, there are certainly times when we might very well have to fly the backside of the power curve, not to confuse a controller, but to achieve a specific task. Ask any bush pilot to describe his technique for landing on a very short landing strip, especially when it is surrounded by obstacles, and he will explain his method as being on the backside of the power curve, balancing pitch and power to keep them on a steep glide slope at slow speed. This is the technique I had to use landing at a 1,900-foot runway (not that that is very short) in the hills of New Hampshire this past summer. It was the end of August on what was perhaps one of the most beautiful days of the year. The temperature was in the mid-70s, the air was smooth with light and variable winds on the ground, and the high pressure helped to create visibilities that don’t get much better, especially in New England. My best friend and I flew up to visit a retired FAA safety program manager and his wife. He has been my mentor and role model not only in aviation safety, but in life as well. We had a wonderful visit, and I was thinking that this had been the best day of the summer for me. All too soon, though, the time for departing arrived. Driving back to the airport, we meandered on a dirt road, through
rolling hills and thick forest, and then suddenly emerged at the airport. The only real indication that we had transitioned to an airport was a windsock, a couple of hangars, and my parked Cardinal RG. Although the runway had been dirt for many years (and really was a continuation of the dirt road), it was now paved with asphalt. It also was not flat, but had a gentle rolling contour similar to the end of a roller coaster ride. The airport narrowed toward the departure end, with rising wooded terrain on both sides, and trees at both ends. (This sure isn’t Kansas, Toto!) At least the density altitude wouldn’t be an issue, what with the moderate temperature, high pressure, dry air, and a field elevation of only 510 feet. The windsock indicated light winds at about 3 knots, favoring a departure to the southwest. The winds wouldn’t be of much help, especially in clearing the trees, but it was better than having no wind at all. After a thorough preflight inspection, we bade our gracious hosts a fond farewell and fired up the Cardinal. After an uneventful run-up and completing the before-takeoff checklists, we taxied to the very end of the runway. Holding the brakes, I applied full power and confirmed that we had the proper manifold pressure, rpm, and oil pressure prior to releasing the brakes. As I looked down the runway I noticed two people walking toward us on
the left side of the runway. They seemed to be moving to the edge of the woods that bordered the airport, so with maximum power still applied I released the brakes and started the take-off roll. Watching to confirm that the airspeed indicator was alive, I saw the airspeed come up to 55 IAS (increased attack speed) and then I noticed it drop back down to about 52 IAS. I momentarily considered aborting the takeoff, but we were already about two-thirds of the way down the runway, and the possibility of not being able to stop before the end of the runway ran through my mind. Virtually at the same time as I completed that thought, the airspeed reached the rotation speed of 65 IAS, and I felt it better to continue the takeoff. We rotated and I lowered the nose to achieve a VX of about 72 IAS (slightly lower than the max gross V X of 75 IAS). We were rapidly approaching some pine trees, and being concerned that we might not clear them I lowered the flaps another 10 degrees to balloon us over the trees, which worked. But now I had used up a lot of energy, and I needed to regain it. That meant I would have to raise the flaps back to a 10-degree setting, which would also mean that we would settle as that occurred. There were still more trees in front of us, so I turned toward the lowest of those. The gear was still extended. Knowing that the worst climb rate is achieved with the gear in transition, but the best rate is with the gear retracted, I decided it might be best to raise the gear, which I did. Heading toward the lowest of the trees, I knew that to get the best climb going I would have to lower the nose, but with the trees in front of us, I was stuck between a rock and a hard spot. Here we were, on the backside of the power curve, with trees fast approaching. The engine, although still running smoothly, was
not making enough power for us to climb. Lowering the nose would put us into the trees, whereas maintaining the pitch I had might clear them. Pulling back on the yoke would put us dangerously close to a stall. With the trees getting ever closer it was difficult not to pull on the yoke. The stall warning started to sound intermittently and I worked the pitch to keep us above stall speed. At this point we were at the trees, and the propeller hit a branch somewhere between 5 and 6 o’clock
. . . then I noticed it drop back down to about 52 IAS. I momentarily considered aborting the takeoff . . . of the propeller arc. Another foot of altitude and we would have cleared the trees. The airplane yawed and banked to the right after the prop hit the top branch of the tree, and then pitched down as we descended through a lot of branches and leaves. When the airplane came to a stop, I had been thrown to the left, to the limits of my seat and shoulder belts. My side of the cockpit (the right side) was crushed in and offered no exit. Releasing my seatbelt, I felt it best to get out of the airplane as soon as possible because of the risk of fire. I managed to crawl across my friend, who appeared unconscious against the left doorpost,
and got outside of the airplane. My friend was not responding to my inquiries of her condition. Once outside the airplane, I was thinking of how to get her out, when a fireman miraculously appeared on the scene. A second fireman appeared and they quickly took charge of the situation. We both suffered severe injuries, but by the time you read this, our recoveries should be almost complete. In fact, three weeks after the accident, I was in the backseat of the L-3 I wrote about in the last article, to finish up that client’s tailwheel transition training. For many student pilots, the landing is considered the most dangerous time of the flight. While it might be the most anxiety producing for the novice pilot, the fact remains that the most dangerous time is the takeoff. It is at this time that we have minimal energy, and altitude. If the yogurt hits the fan, the options are nil. You might very well find yourself stuck between that rock and a hard spot, behind the power curve with nowhere to go. Was there anything I might have done differently? Could I have prevented this accident? You had better believe I spent many a sleepless night during my early recovery going over and over the accident and the events that led up to it. The bruises I suffered were not only physical, but mental and emotional as well. I am happy to say that I am well on the road to a complete recovery. In the next article I will write about the lessons I have learned from this accident, and some suggestions for how to avoid the situation I found myself in. Until then may you be blessed with blue skies and tailwinds. Doug Stewart is the 2004 National CFI of the Year, a NAFI Master Instructor, and a designated pilot examiner. He operates DSFI Inc. (www. DSFlight.com), based at the Columbia County Airport (1B1).
VINTAGE AIRPLANE 23