of the aircraft at the time the reference calls were made, and adding these calls to that elevation, the following tabulation shows (1) the first officer's callout, (2) the flight recorder indication, (3) terrain elevation, and (4) the altitude, if a radio altimeter was being used (terrain plus the callout).
| Callout | Flight Recorder | Terrain Elevation | Terrain Plus Callout |
| 700 feet | 1,330 | 550 | 1,250 |
| 200 above | 1,224 | 530 | 1,120 |
| 400 | 1,005 | 690 | 1,090 |
| Retation prior to tree impact | 925 | 891 |
Based on the above points, the following rates of descent would be required:
| Rates of Descent (feet/minute) | |||
| Between Calls | Flight Data Recorder | Terrain Plus Callouts | |
| "700 feet" to "200 Above" | (5.2 seconds) | 1,155 | 1,386 |
| "200 Above" to "400" | (9.4 seconds) | 1,184 | 1,053 |
| "400" to point of rotation | (2 seconds)[1] | 1,286 | 2,789 |
It is noted that the rates of descent calculated for the flight recorder data are in an increasing pattern and relatively close to the overall rate described by the flight recorder. The rates of descent based on the calculated radio altimeter callouts show close correlation for the initial two call-outs, but in the final segment the descent rate is approximately double the overall rate.
After carefully weighing the conflicting points set forth above, the Board concludes that the theory under consideration -- namely, that the
unrecognized descent through MDA was the result of using the radio altimeter
- ↑ Analysis of aircraft performance data, the flight data recorder, and the cockpit conversation leads to the conclusion that the aircraft was rotated approximately 2 seconds after the callout of 400 feet.
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