Tweet
Lesson Learned
Incident Report - 11/19/2016
It was a beautiful night flight from somewhere-near-San Diego, CA to somewhere-near-San Francisco, CA in the Cherokee. I picked this flight for numerous reasons:
- Night flying currency (it's been a while)
- Radio Navigation challenge (I removed the GPS from the cockpit)
- Elevation/terrain challenges (I flew in-land, towards Palm Springs and northbound along the eastern edge of the Joshua MOAs)
- Weather challenges (many airports in and around San Francisco were reporting IMC at the time of my departure)
The takeoff and cruise portions of the flight went uneventfully, despite an annoying 20-knot quartering head-wind. I got lucky with the cloud bases and didn't have much flying to do in the soup, but I was bouncing from VOR to VOR waypoint with altitude set by the basic autopilot, anyway; visibility wasn't exactly a requirement. I entered into the expected lower ceilings and denser cloud coverage as I approached the destination, and that's where things went wrong. . .
I wanted to descend from my cruising altitude of 10,500 to the IAF altitude (I forget what it was, now... perhaps 5,000 or so) for an ILS approach. No problem; autopilot's altitude hold turned off, power reduced, and down I went. And, at my target altitude, down I still went... and down, and down! All the throttle advancing in the world wasn't going to give me enough power to maintain altitude! It didn't take long to think about Carb Heat, so I pulled the lever... no help. I checked fuel flow, selected a different tank just to be sure; no help. Mixture? Couldn't be; it was already pushed back in during the descent. But wait, was it too rich too soon, and for too long?!
I ended up putting the Cherokee down in a (very fortuitously placed) field about a mile short of the runway -- its REILs blinking tauntingly through the trees.
Everything on the aircraft survived the ditching, including the engine and prop, which continued to spin at well-below the expected RPM despite my throttle inputs. Slowly and surely, it came back alive, though. I ran a quasi-run-up, and sure enough, the mag check revealed that all (or at least most) of the spark plugs appeared to have been fouled.
The lesson: Manage the engine during descent.
I should NOT have gone full-rich so far in advance of needing to actually do so. I also could have ended up like this guy because my carburetor heat wasn't on when it probably should have been.
It was a beautiful night flight from somewhere-near-San Diego, CA to somewhere-near-San Francisco, CA in the Cherokee. I picked this flight for numerous reasons:
- Night flying currency (it's been a while)
- Radio Navigation challenge (I removed the GPS from the cockpit)
- Elevation/terrain challenges (I flew in-land, towards Palm Springs and northbound along the eastern edge of the Joshua MOAs)
- Weather challenges (many airports in and around San Francisco were reporting IMC at the time of my departure)
The takeoff and cruise portions of the flight went uneventfully, despite an annoying 20-knot quartering head-wind. I got lucky with the cloud bases and didn't have much flying to do in the soup, but I was bouncing from VOR to VOR waypoint with altitude set by the basic autopilot, anyway; visibility wasn't exactly a requirement. I entered into the expected lower ceilings and denser cloud coverage as I approached the destination, and that's where things went wrong. . .
I wanted to descend from my cruising altitude of 10,500 to the IAF altitude (I forget what it was, now... perhaps 5,000 or so) for an ILS approach. No problem; autopilot's altitude hold turned off, power reduced, and down I went. And, at my target altitude, down I still went... and down, and down! All the throttle advancing in the world wasn't going to give me enough power to maintain altitude! It didn't take long to think about Carb Heat, so I pulled the lever... no help. I checked fuel flow, selected a different tank just to be sure; no help. Mixture? Couldn't be; it was already pushed back in during the descent. But wait, was it too rich too soon, and for too long?!
I ended up putting the Cherokee down in a (very fortuitously placed) field about a mile short of the runway -- its REILs blinking tauntingly through the trees.
Everything on the aircraft survived the ditching, including the engine and prop, which continued to spin at well-below the expected RPM despite my throttle inputs. Slowly and surely, it came back alive, though. I ran a quasi-run-up, and sure enough, the mag check revealed that all (or at least most) of the spark plugs appeared to have been fouled.
The lesson: Manage the engine during descent.
I should NOT have gone full-rich so far in advance of needing to actually do so. I also could have ended up like this guy because my carburetor heat wasn't on when it probably should have been.