Possible Impact Area
Additional conclusions to determine search grid
At 1912 GMT the three basic fuel remaining scenarios are
1 hour 26 minutes
3 hours 04 minutes (and reductions due to possible failure of the Cambridge Fuel Analyzer)
4 hours 00 minutes
Position estimates result from search maneuvering and estimates of aircraft position in time.
Key points include
At the Path C EON point, the aircraft flys west for 10sm, then east for 10sm, then east another 10sm. At that point, AE reported, “circling,” and embarks on flying the LOP as a magnetic compass heading 337 degrees.
The LOP is flown for 20 minutes, covering 40sm.
A turn east then to a compass heading of 157 degrees, requires 6-7 minutes, where the aircraft then searches southeast.
This pattern is continued until reaching a 4-hour fuel exhaustion point.
Three key locations are added to the search area, corresponding to fuel remaining calculations, from Swenson and Culick, Kelly Johnson/L487, and our analysis.
Key inferences from this analysis include
It is realistic to expect further AE radio reports from 2030 GMT to 2100 GMT, or later.
The aircraft would be located in the search grid at 2100 GMT.
Of the three fuel remaining calculation scenarios
The Kelly Johnson/L487 point is considered least likely.
The Swenson and Culick point is considered possible.
A point between our most optimistic calculation and the Swenson and Culick result is considered the most likely of the fuel exhaustion scenarios, allowing the possibility of an en route failure of the Cambridge Fuel Analyzer, slightly increased fuel consumption rates, and reduced fuel remaining in the Howland Island area.
If AE used fuel differently from this analysis, she likely used more fuel, not less fuel, resulting in fuel exhaustion in less than 3 hours 04 minutes, and within the Search Grid.
Effects of Significant Lateral Deviation North of Path C
If the aircraft passed overhead Nauru Island, it would mean that navigation had either inadvertently deviated 120nm in just three hours since flying over Nukumanu Island, or the course deviation was intentional to facilitate sighting Nauru’s expected lights, and logging the last good navigation fix until Howland Island.
An inadvertent deviation of this magnitude is very unlikely.
Intentionally passing overhead the island to establish a position is a reasonable intention. Unfortunately, there is no evidence to support the theory.
If we suppose that it did occur, then the course to Howland Island from overhead Nauru Island converges with the Path C track, terminating within a few miles northwest of the Path C End-of-Navigation point.
No matter how close to Nauru Island the Electra passed, at 1912 GMT on Path C it would be located within the Search Grid, very near the Path C EON point.
From a position overhead Nauru Island, another possible course would parallel Path C to 1912 GMT.
This is considered unlikely, as it would indicate intentional navigation to a point other than Howland Island, or a failure to correctly navigate to Howland Island.
The effects of reasonable lateral deviations place the aircraft in the existing Search Grid for scenarios of wind and weather considered possible, or likely.