Nightfall to Ship In Sight

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by Randy Jacobson

In our analysis of Lae to Nightfall we concluded that at sometime around 0700Z the flight was near the Nukumanu Islands having covered about 735 nm since its departure from Lae. The airplane’s average groundspeed up to that time was 105 kts if the takeoff occurred at 0000Z; 116 kts if the flight actually commenced 22 minutes later. In either case, the average groundspeed was influenced by the necessarily slow, heavily overloaded climb to altitude. Deviations around rainsqualls forecast for the area 300 miles east of Lae could have also slowed the average groundspeed. Regardless of how it got there, at 0700Z , with night approaching, the flight seems to have been on course and roughly a third of the way to Howland. Its altitude, speed and fuel are harder to pin down.

Positions of USS Ontario and MV Myrtlebank

According to Chater, the flight was at 8,000 feet. Collopy says 7,000 feet. If Earhart followed a program similar to the one Kelly Johnson recommended for the Oakland/Honolulu flight, she initially climbed to 4,000 feet, stayed there for three hours, then climbed to 6,000 feet and remained at that altitude for another three hours. Whether the plane has been aloft for 7 hours (0000Z takeoff) or 6.6 hours (0022Z takeoff), 7 or 8 thousand feet is on the optimistic side of where it should be at 0700Z.

Likewise, the plane’s reported current speed is better than expected. According to Chater, Earhart said “wind 23 knots.” Collopy has her saying the plane is “making 150 knots.” The only way both can be correct is if there is a tailwind, but Lt. True’s forecast was for a quartering headwind. (“Winds east southeast about 25 knots to Ontario then east to east northeast about 20 knots to Howland.”) The forecast, however, was based on True’s perception of typical conditions in the region rather than on actual observations. The only report of observed winds aloft in the region is an out of date report from the island of Nauru, over 500 miles away and abut 100 miles north of Earhart’s route to Howland. Ten hours earlier, the wind at 7,500 ft there was out of the east at 19 knots.

The next time when we have an indication of where the flight is at a particular moment in time is three and a half hours later at 1030Z when the radio operator on Nauru heard her say, “Ship in sight ahead.” The only ships known to have been in the area were USS Ontario, on station at 2°59.02′S, 165°23.20′E to provide assistance to Earhart, and MV Myrtlebank, a freighter located, as close as can be determined, in "a 20nm by 10nm region oriented at 350° centered at 2°20′S, 167°10′E." (see Randy Jacobson’s analysis)

Earhart’s reported 1030Z transmission has the advantage of being an off-schedule description of a real-time event. If the ship in sight ahead was USS Ontario, the Electra had flown 350 nm in 3.5 hrs for an average sped of 100 kts, suggesting that the flight was encountering a 30 kt. headwind. If the ship was MV Myrtlebank, the distance covered was 462 nm and the speed was 132 kts, suggesting a 2 kt. tailwind component. Again, these are ballpark numbers, not precise calculations, but they present the same question posed by Earhart’s 0718Z position report. Was the flight encountering significant headwinds or getting some help from an unexpected tailwind?

USS Ontario

It depends on which ship she saw. Of course, several hours after sundown she didn’t see a ship. She saw lights. The deck logs of the Ontario recorded calm seas, visibility at least 40 miles, and cloud cover from 20 to 40% and light winds from the east. There was no radio communication with the plane, nor was any expected. No one aboard Ontario reported seeing or hearing an airplane.

MV Myrtlebank was a standard British freighter owned by Bank Line Ltd. and chartered to the British Phosphate Commission at Nauru. She was en route to Nauru from New Zealand making about 10 knots roughly 80 nm due south of Nauru. In 1990, a resident of Australia, Syd Dowdeswell, contacted TIGHAR . Dowdeswell had been Third Mate aboard Myrtlebank and had the 8 P.M. to midnight watch on the night in question. He recalled that the night was "clear and fine" and the lights visible on the ship were the usual running lights, engine room skylights, and cabin portholes.

Around 10 P.M. Dowdeswell was surprised to hear the sound of an aircraft coming from the starboard quarter and lasting about a minute. He reported the incident to the captain who received it "with some skepticism" because aircraft were virtually unknown in that part of the Pacific at that time and neither Dowdeswell nor the captain knew about Earhart’s flight.

In 1937, local time at Nauru was Greenwich minus 10.5 hours. If Myrtlebank was still on New Zealand time (Greenwich minus 11 hours) the time Dowdeswell claimed to have heard an airplane closely matches the time the Nauru operator heard Earhart say “Ship in sight ahead.” Myrtlebank’s estimated position was somewhat to the north of Earhart’s course to Howland. The ship was on a northerly heading and the wind was from the east. Dowdeswell’s recollection of hearing a plane off the ship’s starboard quarter (right rear) suggests that he heard the plane as it passed behind the ship a few minutes after Earhart’s broadcast. On balance, there appears to be reason to conclude that the ship Earhart saw was MV Myrtlebank.

MV Myrtlebank and NR16020 position analysis

"Ship" vs. "Lights" in sight

Ric Gillespie, Forum, 25 April 2011.
The original source is a State Department telegram from Sydney, Australia dated July 3m 1937, which reads: “Amalgamated Wireless state information received that report from ‘Nauru’ was sent to Bolinas Radio ‘at 6.31, 6.43 and 6.54 PM Sydney time today on 48.31 meters (6210 kHz), fairly strong signals, speech not intelligible, no hum of plane in background but voice similar that emitted from plane in flight last night between 4.30 and 9.30 P.M.’ Message from plane when at least 60 miles south of Nauru received 8.30 P.M. Sydney time, July 2 saying ‘A ship in sight ahead.’ Since identified as steamer Myrtle Bank sic which arrived Nauru daybreak today."
Unless Mr. Cude produced the actual radio log for that night, the contemporary written record (the State Dept. telegram) trumps his 20+ year-old recollection.