CONTROLLED FLIGHT INTO TERRAIN: UNSTABILIZED APPROACH
This accident is where the pilot flies an unstabilized approach and never discontinues the approach, but instead forces the plane onto the runway. The result is usually a long landing going off the opposite end.
Depending on the terrain and circumstances, not all accidents are fatal, but each result in a runway excursion either laterally or past the end. The FAA asks for stabilized approaches in numerous documents for GA but never defines exactly what criteria defines a stabilized approach.
SOLUTION:
In order to be able to know what is NOT a stabilized approach, we must define exactly what a stabilized approach is.
A stabilized approach for General Aviation must meet these four criteria:
1. On a vertical path of some kind. This can be VASI, PAPI, Glide Slope, LPV vertical path, or just visual cues. A constant VSI that is stable and not excessive is one indicator of being on the path.
2. Speed stabilized a V Ref. Determine what your target speed is going to be prior to being on final. This will always vary according to aircraft, weight, weather, runway length and possibly more criteria. The point is to determine what speed is going to be the REF speed for the approach and honor it.
3. On Centerline. Uncommanded lateral drifts off the centerline are obvious to the pilot and cannot be accepted. Slight variances may be tolerable depending on conditions and runway width, this consideration should be acknowledged prior to commencing the approach.
4. Touchdown in the touchdown zone. Some runways are marked with a white instrument box that indicates a Touch down point. In absence of any TDZ markings, use the first third of a long runway (greater than 6000 feet) as a target. Use the first quarter as target on a shorter runway (4000-6000 feet) use first fifth on short runways (2500-4000 feet) Use first sixth as target on runways less than 2500. Develop your own criteria for your own plane and your own flying. The ones listed here may not meet your needs. Define your own TDZ definitions and include it in your own briefings.
Depending on if you are IFR, VFR, IMC or VMC, you should have all four of these criteria met at some target “gate” on each approach. The gates are typically 1000 AGL at the highest for solid IMC approaches in heavy aircraft, to as low as 300 AGL is VFR light aircraft.
The solution is to know your targets and be ready and willing to Go Around when you do not have all four criteria totally met by the gate that you established.
SAMPLE ACCIDENT REPORT:
The flight crew's failure to maintain airplane control during landing following an unstabilized approach. Contributing to the accident were the flight crew's decision to land with a tailwind above the airplane's operating limitations and their failure not to conduct a go-around when the approach became unstabilized.
NEED SAMPLE ACCIDENT REPORT NUMBER AND LINK